diff mbox series

[1/2] rockchip: rk3588: Add support for ATAG parsing

Message ID 20240326204944.1572667-2-macroalpha82@gmail.com
State RFC
Delegated to: Kever Yang
Headers show
Series Use ATAGs for RK3588 For RAM Info | expand

Commit Message

Chris Morgan March 26, 2024, 8:49 p.m. UTC
From: Chris Morgan <macromorgan@hotmail.com>

Add support for parsing the ATAGs created by the Rockchip binary
RAM init. This ATAG parsing code was taken from the Rockchip BSP
U-Boot source and tested only on parsing the RAM specific ATAGs
for the RK3588.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
---
 arch/arm/include/asm/arch-rockchip/atags.h | 222 +++++++++++++++++++++
 arch/arm/mach-rockchip/Makefile            |   1 +
 arch/arm/mach-rockchip/atags.c             |  99 +++++++++
 3 files changed, 322 insertions(+)
 create mode 100644 arch/arm/include/asm/arch-rockchip/atags.h
 create mode 100644 arch/arm/mach-rockchip/atags.c

Comments

Quentin Schulz March 27, 2024, 9:45 a.m. UTC | #1
Hi Chris,

On 3/26/24 21:49, Chris Morgan wrote:
> From: Chris Morgan <macromorgan@hotmail.com>
> 
> Add support for parsing the ATAGs created by the Rockchip binary
> RAM init. This ATAG parsing code was taken from the Rockchip BSP
> U-Boot source and tested only on parsing the RAM specific ATAGs
> for the RK3588.
> 

Can you tell us from which commit (and maybe branch/tag in the event 
they rename/rebase/delete branches) exactly so we can check if they fix 
stuff downstream every now and then?

> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> ---
>   arch/arm/include/asm/arch-rockchip/atags.h | 222 +++++++++++++++++++++
>   arch/arm/mach-rockchip/Makefile            |   1 +
>   arch/arm/mach-rockchip/atags.c             |  99 +++++++++
>   3 files changed, 322 insertions(+)
>   create mode 100644 arch/arm/include/asm/arch-rockchip/atags.h
>   create mode 100644 arch/arm/mach-rockchip/atags.c
> 
> diff --git a/arch/arm/include/asm/arch-rockchip/atags.h b/arch/arm/include/asm/arch-rockchip/atags.h
> new file mode 100644
> index 0000000000..9bae66d7f8
> --- /dev/null
> +++ b/arch/arm/include/asm/arch-rockchip/atags.h
> @@ -0,0 +1,222 @@
> +/* SPDX-License-Identifier:     GPL-2.0+ */
> +/*
> + * (C) Copyright 2018 Rockchip Electronics Co., Ltd
> + *
> + */
> +
> +#ifndef __RK_ATAGS_H_
> +#define __RK_ATAGS_H_
> +
> +/* Tag magic */
> +#define ATAG_CORE		0x54410001
> +#define ATAG_NONE		0x00000000
> +
> +#define ATAG_SERIAL		0x54410050
> +#define ATAG_BOOTDEV		0x54410051
> +#define ATAG_DDR_MEM		0x54410052
> +#define ATAG_TOS_MEM		0x54410053
> +#define ATAG_RAM_PARTITION	0x54410054
> +#define ATAG_ATF_MEM		0x54410055
> +#define ATAG_PUB_KEY		0x54410056
> +#define ATAG_SOC_INFO		0x54410057
> +#define ATAG_BOOT1_PARAM	0x54410058
> +#define ATAG_PSTORE		0x54410059
> +#define ATAG_FWVER		0x5441005a
> +#define ATAG_MAX		0x544100ff
> +
> +/* Tag size and offset */
> +#define ATAGS_SIZE		(0x2000)	/* 8K */
> +#define ATAGS_OFFSET		(0x200000 - ATAGS_SIZE)/* [2M-8K, 2M] */
> +#define ATAGS_PHYS_BASE		(CFG_SYS_SDRAM_BASE + ATAGS_OFFSET)
> +
> +/* tag_fwver.ver[fwid][] */
> +#define FWVER_LEN		36
> +
> +enum fwid {
> +	FW_DDR,
> +	FW_SPL,
> +	FW_ATF,
> +	FW_TEE,
> +	FW_MAX,
> +};
> +
> +struct tag_serial {
> +	u32 version;
> +	u32 enable;
> +	u64 addr;
> +	u32 baudrate;
> +	u32 m_mode;
> +	u32 id;
> +	u32 reserved[2];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_bootdev {
> +	u32 version;
> +	u32 devtype;
> +	u32 devnum;
> +	u32 mode;
> +	u32 sdupdate;
> +	u32 reserved[6];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_ddr_mem {
> +	u32 count;
> +	u32 version;
> +	u64 bank[20];
> +	u32 flags;
> +	u32 data[2];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_tos_mem {
> +	u32 version;
> +	struct {
> +		char name[8];
> +		u64 phy_addr;
> +		u32 size;
> +		u32 flags;
> +	} tee_mem;
> +
> +	struct {
> +		char name[8];
> +		u64 phy_addr;
> +		u32 size;
> +		u32 flags;
> +	} drm_mem;
> +
> +	u64 reserved[7];
> +	u32 reserved1;
> +	u32 hash;
> +} __packed;
> +
> +struct tag_atf_mem {
> +	u32 version;
> +	u64 phy_addr;
> +	u32 size;
> +	u32 flags;
> +	u32 reserved[2];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_pub_key {
> +	u32 version;
> +	u32 len;
> +	u8  data[768];	/* u32 rsa_n[64], rsa_e[64], rsa_c[64] */
> +	u32 flag;
> +	u32 reserved[5];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_ram_partition {
> +	u32 version;
> +	u32 count;
> +	u32 reserved[4];
> +
> +	struct {
> +		char name[16];
> +		u64 start;
> +		u64 size;
> +	} part[6];
> +
> +	u32 reserved1[3];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_soc_info {
> +	u32 version;
> +	u32 name;	/* Hex: 0x3288, 0x3399... */
> +	u32 flags;
> +	u32 reserved[6];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_boot1p {
> +	u32 version;
> +	u32 param[8];
> +	u32 reserved[4];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_pstore {
> +	u32 version;
> +	struct {
> +		u32 addr;
> +		u32 size;
> +	} buf[16];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_fwver {
> +	u32 version;
> +	char ver[8][FWVER_LEN];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_core {
> +	u32 flags;
> +	u32 pagesize;
> +	u32 rootdev;
> +} __packed;
> +
> +struct tag_header {
> +	u32 size;	/* bytes = size * 4 */
> +	u32 magic;
> +} __packed;
> +
> +/* Must be 4 bytes align */
> +struct tag {
> +	struct tag_header hdr;
> +	union {
> +		struct tag_core		core;
> +		struct tag_serial	serial;
> +		struct tag_bootdev	bootdev;
> +		struct tag_ddr_mem	ddr_mem;
> +		struct tag_tos_mem	tos_mem;
> +		struct tag_ram_partition ram_part;
> +		struct tag_atf_mem	atf_mem;
> +		struct tag_pub_key	pub_key;
> +		struct tag_soc_info	soc;
> +		struct tag_boot1p	boot1p;
> +		struct tag_pstore	pstore;
> +		struct tag_fwver	fwver;
> +	} u;
> +} __aligned(4);
> +
> +#define tag_next(t)	((struct tag *)((u32 *)(t) + (t)->hdr.size))
> +#define tag_size(type)	((sizeof(struct tag_header) + sizeof(struct type)) >> 2)
> +#define for_each_tag(t, base)		\
> +	for (t = base; t->hdr.size; t = tag_next(t))
> +
> +/*
> + * atags_get_tag - get tag by tag magic
> + *
> + * @magic: tag magic, i.e. ATAG_SERIAL, ATAG_BOOTDEV, ...
> + *
> + * return: NULL on failed, otherwise return the tag that we want.
> + */
> +struct tag *atags_get_tag(u32 magic);
> +
> +/*
> + * atags_is_available - check if atags is available, used for second or
> + *			later pre-loaders.
> + *
> + * return: 0 is not available, otherwise available.
> + */
> +int atags_is_available(void);
> +
> +/*
> + * atags_overflow - check if atags is overflow
> + *

This is not really useful to the user to know what this is doing.

I could suggest this rewording:

"""
check if the tag t is a valid atag: entirely contained in the ATAGS 
physical address space [ATAGS_PHYS_BASE; ATAGS_PHYS_BASE + ATAGS_SIZE]
"""

> + * return: 0 if not overflow, otherwise overflow.
> + */
> +int atags_overflow(struct tag *t);
> +
> +/*
> + * atags_bad_magic - check if atags magic is invalid.
> + *
> + * return: 1 if invalid, otherwise valid.
> + */
> +int atags_bad_magic(u32 magic);
> +#endif
> diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
> index 1dc92066bb..4165cbe99f 100644
> --- a/arch/arm/mach-rockchip/Makefile
> +++ b/arch/arm/mach-rockchip/Makefile
> @@ -28,6 +28,7 @@ endif
>   
>   ifeq ($(CONFIG_TPL_BUILD),)
>   obj-$(CONFIG_DISPLAY_CPUINFO) += cpu-info.o
> +obj-$(CONFIG_ROCKCHIP_RK3588) += atags.o

Please define a new symbol instead, you can "imply" it for RK35xx boards 
in a follow-up patch then.

Now to come to think of it... Maybe we should make ROCKCHIP_EXTERNAL_TPL 
imply ROCKCHIP_ATAGS? That would be the most sensible thing to do I believe?

I think we should also probably make different symbols for SPL and 
U-Boot proper (if we want to support the later). SPL would be "required" 
for any platform with a blob from Rockchip as TPL but U-Boot proper 
support only makes sense for debugging (e.g. if there's an atags command 
in U-Boot to dump them).

>   endif
>   
>   obj-$(CONFIG_$(SPL_TPL_)RAM) += sdram.o
> diff --git a/arch/arm/mach-rockchip/atags.c b/arch/arm/mach-rockchip/atags.c
> new file mode 100644
> index 0000000000..9daa2f2fc0
> --- /dev/null
> +++ b/arch/arm/mach-rockchip/atags.c
> @@ -0,0 +1,99 @@
> +// SPDX-License-Identifier:     GPL-2.0+
> +/*
> + * (C) Copyright 2018 Rockchip Electronics Co., Ltd.
> + *
> + */
> +
> +#include <config.h>

If I remember correctly, Tom has been hunting those config.h includes 
down, so better remove it if everything works as well :)

> +#include <asm/io.h>
> +#include <asm/arch-rockchip/atags.h>
> +
> +#define HASH_LEN	sizeof(u32)
> +
> +static u32 js_hash(void *buf, u32 len)
> +{
> +	u32 i, hash = 0x47C6A7E6;
> +	char *data = buf;
> +
> +	if (!buf || !len)
> +		return hash;
> +
> +	for (i = 0; i < len; i++)
> +		hash ^= ((hash << 5) + data[i] + (hash >> 2));
> +
> +	return hash;
> +}
> +
> +int atags_bad_magic(u32 magic)
> +{
> +	bool bad;
> +
> +	bad = ((magic != ATAG_CORE) &&
> +	       (magic != ATAG_NONE) &&
> +	       (magic < ATAG_SERIAL || magic > ATAG_MAX));
> +	if (bad)
> +		printf("Magic(%x) is not support\n", magic);
> +

"""
switch (magic) {
case ATAG_NONE:
case ATAG_CORE:
case ATAG_SERIAL ... ATAG_MAX:
     return false;
default:
     printf("Magic(%x) is not supported\n", magic);
     return true;
}
"""

may be a tiny bit more readable but that's a matter of taste, so up to you.

Otherwise:
- The error message has a typo: should be "not supported".
- I would recommend to use 0x%x so that it highlights it is a 
hexadecimal value.
- Use pr_err() or debug() instead of printf(), this applies to all 
printf in this patch. I **think**, debug() may be more warranted.

> +	return bad;
> +}
> +
> +static int atags_size_overflow(struct tag *t, u32 tag_size)
> +{
> +	return (unsigned long)t + (tag_size << 2) - ATAGS_PHYS_BASE > ATAGS_SIZE;

"""
tag_size << 2
"""

may overflow itself, should we cast this into a u64 before the shift?

Similarly, unsigned long being 32b,

"""
(unsigned long)t + (tag_size << 2)
"""

32b + 32b may overflow a 32b container.

Actually, maybe... we should be using phys_addr_t for this? It's an 
unsigned long long so 64b container for 64b archs and it represents what 
this is... a physical address?

Also, this can technically underflow as well, if (unsigned long)t + 
(tag_size << 2) is smaller than ATAGS_PHYS_BASE.

> +}
> +
> +int atags_overflow(struct tag *t)
> +{
> +	bool overflow;
> +
> +	overflow = atags_size_overflow(t, 0) ||
> +		   atags_size_overflow(t, t->hdr.size);

I don't really understand why we need to check for size 0? Do you have 
an idea what Rockchip wanted to do here?

> +	if (overflow)
> +		printf("Tag is overflow\n");
> + > +	return overflow;
> +}
> +
> +int atags_is_available(void)
> +{
> +	struct tag *t = (struct tag *)ATAGS_PHYS_BASE;
> +
> +	return (t->hdr.magic == ATAG_CORE);
> +}
> +
> +struct tag *atags_get_tag(u32 magic)
> +{
> +	u32 *hash, calc_hash, size;
> +	struct tag *t;
> +
> +	if (!atags_is_available())
> +		return NULL;
> +
> +	for_each_tag(t, (struct tag *)ATAGS_PHYS_BASE) {
> +		if (atags_overflow(t))
> +			return NULL;
> +
> +		if (atags_bad_magic(t->hdr.magic))
> +			return NULL;
> +
> +		if (t->hdr.magic != magic)
> +			continue;
> +
> +		size = t->hdr.size;
> +		hash = (u32 *)((ulong)t + (size << 2) - HASH_LEN);

Same issue of possible overflows as in atags_size_overflow().

> +		if (!*hash) {

I assume this is "safe" because we check this is a "valid" physical 
address within the expected boundaries of ATAGS address space with 
`atags_overflow()`.

> +			debug("No hash, magic(%x)\n", magic);
> +			return t;
> +		}
> +		calc_hash = js_hash(t, (size << 2) - HASH_LEN);

Ditto.

Cheers,
Quentin
Kever Yang March 27, 2024, 10:32 a.m. UTC | #2
Hi Chris,

     The ATAGS is used for passing parameter from bootloader to kernel 
at first, which has been replaced by DTB now for ARM platform.

     And Rockchip using ATAGs for passing parameter like dram memory 
size/board uart in different boot process like DRAM init binary/ TPL/SPL 
to U-Boot since 2018.

     And almost at the same time, Simon add bloblist for mainline U-Boot 
which for similar purpose.

     So I'm not sure if this ATAGS should be accept in mainline U-Boot 
or not, even for rockchip platform only seems some kind of regression 
for this feature support.


Hi Simon and Tom,

      Could you help to give some suggestion for this?


Thanks,
- Kever
On 2024/3/27 04:49, Chris Morgan wrote:
> From: Chris Morgan <macromorgan@hotmail.com>
>
> Add support for parsing the ATAGs created by the Rockchip binary
> RAM init. This ATAG parsing code was taken from the Rockchip BSP
> U-Boot source and tested only on parsing the RAM specific ATAGs
> for the RK3588.
>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> ---
>   arch/arm/include/asm/arch-rockchip/atags.h | 222 +++++++++++++++++++++
>   arch/arm/mach-rockchip/Makefile            |   1 +
>   arch/arm/mach-rockchip/atags.c             |  99 +++++++++
>   3 files changed, 322 insertions(+)
>   create mode 100644 arch/arm/include/asm/arch-rockchip/atags.h
>   create mode 100644 arch/arm/mach-rockchip/atags.c
>
> diff --git a/arch/arm/include/asm/arch-rockchip/atags.h b/arch/arm/include/asm/arch-rockchip/atags.h
> new file mode 100644
> index 0000000000..9bae66d7f8
> --- /dev/null
> +++ b/arch/arm/include/asm/arch-rockchip/atags.h
> @@ -0,0 +1,222 @@
> +/* SPDX-License-Identifier:     GPL-2.0+ */
> +/*
> + * (C) Copyright 2018 Rockchip Electronics Co., Ltd
> + *
> + */
> +
> +#ifndef __RK_ATAGS_H_
> +#define __RK_ATAGS_H_
> +
> +/* Tag magic */
> +#define ATAG_CORE		0x54410001
> +#define ATAG_NONE		0x00000000
> +
> +#define ATAG_SERIAL		0x54410050
> +#define ATAG_BOOTDEV		0x54410051
> +#define ATAG_DDR_MEM		0x54410052
> +#define ATAG_TOS_MEM		0x54410053
> +#define ATAG_RAM_PARTITION	0x54410054
> +#define ATAG_ATF_MEM		0x54410055
> +#define ATAG_PUB_KEY		0x54410056
> +#define ATAG_SOC_INFO		0x54410057
> +#define ATAG_BOOT1_PARAM	0x54410058
> +#define ATAG_PSTORE		0x54410059
> +#define ATAG_FWVER		0x5441005a
> +#define ATAG_MAX		0x544100ff
> +
> +/* Tag size and offset */
> +#define ATAGS_SIZE		(0x2000)	/* 8K */
> +#define ATAGS_OFFSET		(0x200000 - ATAGS_SIZE)/* [2M-8K, 2M] */
> +#define ATAGS_PHYS_BASE		(CFG_SYS_SDRAM_BASE + ATAGS_OFFSET)
> +
> +/* tag_fwver.ver[fwid][] */
> +#define FWVER_LEN		36
> +
> +enum fwid {
> +	FW_DDR,
> +	FW_SPL,
> +	FW_ATF,
> +	FW_TEE,
> +	FW_MAX,
> +};
> +
> +struct tag_serial {
> +	u32 version;
> +	u32 enable;
> +	u64 addr;
> +	u32 baudrate;
> +	u32 m_mode;
> +	u32 id;
> +	u32 reserved[2];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_bootdev {
> +	u32 version;
> +	u32 devtype;
> +	u32 devnum;
> +	u32 mode;
> +	u32 sdupdate;
> +	u32 reserved[6];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_ddr_mem {
> +	u32 count;
> +	u32 version;
> +	u64 bank[20];
> +	u32 flags;
> +	u32 data[2];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_tos_mem {
> +	u32 version;
> +	struct {
> +		char name[8];
> +		u64 phy_addr;
> +		u32 size;
> +		u32 flags;
> +	} tee_mem;
> +
> +	struct {
> +		char name[8];
> +		u64 phy_addr;
> +		u32 size;
> +		u32 flags;
> +	} drm_mem;
> +
> +	u64 reserved[7];
> +	u32 reserved1;
> +	u32 hash;
> +} __packed;
> +
> +struct tag_atf_mem {
> +	u32 version;
> +	u64 phy_addr;
> +	u32 size;
> +	u32 flags;
> +	u32 reserved[2];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_pub_key {
> +	u32 version;
> +	u32 len;
> +	u8  data[768];	/* u32 rsa_n[64], rsa_e[64], rsa_c[64] */
> +	u32 flag;
> +	u32 reserved[5];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_ram_partition {
> +	u32 version;
> +	u32 count;
> +	u32 reserved[4];
> +
> +	struct {
> +		char name[16];
> +		u64 start;
> +		u64 size;
> +	} part[6];
> +
> +	u32 reserved1[3];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_soc_info {
> +	u32 version;
> +	u32 name;	/* Hex: 0x3288, 0x3399... */
> +	u32 flags;
> +	u32 reserved[6];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_boot1p {
> +	u32 version;
> +	u32 param[8];
> +	u32 reserved[4];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_pstore {
> +	u32 version;
> +	struct {
> +		u32 addr;
> +		u32 size;
> +	} buf[16];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_fwver {
> +	u32 version;
> +	char ver[8][FWVER_LEN];
> +	u32 hash;
> +} __packed;
> +
> +struct tag_core {
> +	u32 flags;
> +	u32 pagesize;
> +	u32 rootdev;
> +} __packed;
> +
> +struct tag_header {
> +	u32 size;	/* bytes = size * 4 */
> +	u32 magic;
> +} __packed;
> +
> +/* Must be 4 bytes align */
> +struct tag {
> +	struct tag_header hdr;
> +	union {
> +		struct tag_core		core;
> +		struct tag_serial	serial;
> +		struct tag_bootdev	bootdev;
> +		struct tag_ddr_mem	ddr_mem;
> +		struct tag_tos_mem	tos_mem;
> +		struct tag_ram_partition ram_part;
> +		struct tag_atf_mem	atf_mem;
> +		struct tag_pub_key	pub_key;
> +		struct tag_soc_info	soc;
> +		struct tag_boot1p	boot1p;
> +		struct tag_pstore	pstore;
> +		struct tag_fwver	fwver;
> +	} u;
> +} __aligned(4);
> +
> +#define tag_next(t)	((struct tag *)((u32 *)(t) + (t)->hdr.size))
> +#define tag_size(type)	((sizeof(struct tag_header) + sizeof(struct type)) >> 2)
> +#define for_each_tag(t, base)		\
> +	for (t = base; t->hdr.size; t = tag_next(t))
> +
> +/*
> + * atags_get_tag - get tag by tag magic
> + *
> + * @magic: tag magic, i.e. ATAG_SERIAL, ATAG_BOOTDEV, ...
> + *
> + * return: NULL on failed, otherwise return the tag that we want.
> + */
> +struct tag *atags_get_tag(u32 magic);
> +
> +/*
> + * atags_is_available - check if atags is available, used for second or
> + *			later pre-loaders.
> + *
> + * return: 0 is not available, otherwise available.
> + */
> +int atags_is_available(void);
> +
> +/*
> + * atags_overflow - check if atags is overflow
> + *
> + * return: 0 if not overflow, otherwise overflow.
> + */
> +int atags_overflow(struct tag *t);
> +
> +/*
> + * atags_bad_magic - check if atags magic is invalid.
> + *
> + * return: 1 if invalid, otherwise valid.
> + */
> +int atags_bad_magic(u32 magic);
> +#endif
> diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
> index 1dc92066bb..4165cbe99f 100644
> --- a/arch/arm/mach-rockchip/Makefile
> +++ b/arch/arm/mach-rockchip/Makefile
> @@ -28,6 +28,7 @@ endif
>   
>   ifeq ($(CONFIG_TPL_BUILD),)
>   obj-$(CONFIG_DISPLAY_CPUINFO) += cpu-info.o
> +obj-$(CONFIG_ROCKCHIP_RK3588) += atags.o
>   endif
>   
>   obj-$(CONFIG_$(SPL_TPL_)RAM) += sdram.o
> diff --git a/arch/arm/mach-rockchip/atags.c b/arch/arm/mach-rockchip/atags.c
> new file mode 100644
> index 0000000000..9daa2f2fc0
> --- /dev/null
> +++ b/arch/arm/mach-rockchip/atags.c
> @@ -0,0 +1,99 @@
> +// SPDX-License-Identifier:     GPL-2.0+
> +/*
> + * (C) Copyright 2018 Rockchip Electronics Co., Ltd.
> + *
> + */
> +
> +#include <config.h>
> +#include <asm/io.h>
> +#include <asm/arch-rockchip/atags.h>
> +
> +#define HASH_LEN	sizeof(u32)
> +
> +static u32 js_hash(void *buf, u32 len)
> +{
> +	u32 i, hash = 0x47C6A7E6;
> +	char *data = buf;
> +
> +	if (!buf || !len)
> +		return hash;
> +
> +	for (i = 0; i < len; i++)
> +		hash ^= ((hash << 5) + data[i] + (hash >> 2));
> +
> +	return hash;
> +}
> +
> +int atags_bad_magic(u32 magic)
> +{
> +	bool bad;
> +
> +	bad = ((magic != ATAG_CORE) &&
> +	       (magic != ATAG_NONE) &&
> +	       (magic < ATAG_SERIAL || magic > ATAG_MAX));
> +	if (bad)
> +		printf("Magic(%x) is not support\n", magic);
> +
> +	return bad;
> +}
> +
> +static int atags_size_overflow(struct tag *t, u32 tag_size)
> +{
> +	return (unsigned long)t + (tag_size << 2) - ATAGS_PHYS_BASE > ATAGS_SIZE;
> +}
> +
> +int atags_overflow(struct tag *t)
> +{
> +	bool overflow;
> +
> +	overflow = atags_size_overflow(t, 0) ||
> +		   atags_size_overflow(t, t->hdr.size);
> +	if (overflow)
> +		printf("Tag is overflow\n");
> +
> +	return overflow;
> +}
> +
> +int atags_is_available(void)
> +{
> +	struct tag *t = (struct tag *)ATAGS_PHYS_BASE;
> +
> +	return (t->hdr.magic == ATAG_CORE);
> +}
> +
> +struct tag *atags_get_tag(u32 magic)
> +{
> +	u32 *hash, calc_hash, size;
> +	struct tag *t;
> +
> +	if (!atags_is_available())
> +		return NULL;
> +
> +	for_each_tag(t, (struct tag *)ATAGS_PHYS_BASE) {
> +		if (atags_overflow(t))
> +			return NULL;
> +
> +		if (atags_bad_magic(t->hdr.magic))
> +			return NULL;
> +
> +		if (t->hdr.magic != magic)
> +			continue;
> +
> +		size = t->hdr.size;
> +		hash = (u32 *)((ulong)t + (size << 2) - HASH_LEN);
> +		if (!*hash) {
> +			debug("No hash, magic(%x)\n", magic);
> +			return t;
> +		}
> +		calc_hash = js_hash(t, (size << 2) - HASH_LEN);
> +		if (calc_hash == *hash) {
> +			debug("Hash okay, magic(%x)\n", magic);
> +			return t;
> +		}
> +		debug("Hash bad, magic(%x), orgHash=%x, nowHash=%x\n",
> +		      magic, *hash, calc_hash);
> +		return NULL;
> +	}
> +
> +	return NULL;
> +}
Tom Rini March 27, 2024, 12:12 p.m. UTC | #3
On Wed, Mar 27, 2024 at 06:32:06PM +0800, Kever Yang wrote:
> Hi Chris,
> 
>     The ATAGS is used for passing parameter from bootloader to kernel at
> first, which has been replaced by DTB now for ARM platform.
> 
>     And Rockchip using ATAGs for passing parameter like dram memory
> size/board uart in different boot process like DRAM init binary/ TPL/SPL to
> U-Boot since 2018.
> 
>     And almost at the same time, Simon add bloblist for mainline U-Boot
> which for similar purpose.
> 
>     So I'm not sure if this ATAGS should be accept in mainline U-Boot or
> not, even for rockchip platform only seems some kind of regression for this
> feature support.
> 
> 
> Hi Simon and Tom,
> 
>      Could you help to give some suggestion for this?

This should be using bloblist, yes, as I understand it.
Chris Morgan March 27, 2024, 1:32 p.m. UTC | #4
On Wed, Mar 27, 2024 at 06:32:06PM +0800, Kever Yang wrote:
> Hi Chris,
> 
>     The ATAGS is used for passing parameter from bootloader to kernel at
> first, which has been replaced by DTB now for ARM platform.
> 
>     And Rockchip using ATAGs for passing parameter like dram memory
> size/board uart in different boot process like DRAM init binary/ TPL/SPL to
> U-Boot since 2018.
> 
>     And almost at the same time, Simon add bloblist for mainline U-Boot
> which for similar purpose.
> 
>     So I'm not sure if this ATAGS should be accept in mainline U-Boot or
> not, even for rockchip platform only seems some kind of regression for this
> feature support.
> 
> 
> Hi Simon and Tom,
> 
>      Could you help to give some suggestion for this?
> 

I really meant to do this as an "RFC", so I apologize in advance for
possibly causing more work in treating this as a full-fledged patch.

The problem I'm trying to solve is that I've got 2 boards, a Rock 5B
as well as an Indiedroid Nova both with 16GB of RAM. I noticed that
without the memory holes the Rock 5B defined in my Indiedroid it would
also fail to boot. I've got 2 other boards as well with less than 16GB
of RAM which seem to work fine without any holes (a 4GB Indiedroid Nova
prototype and a GameForce Ace with 12GB of RAM).

The "RFC" part for which I'm really requesting guidance/comments is
a question of "is it appropriate to use ATAGS" to get the RAM banks
on this SoC, or is there a different way we should be doing it? If
we can/should use the ATAGS, then I guess this can be pared down and
refactored to just be RK3588 specific. If so, we can possibly add
something like this to the RK3588 SoC specific code, guard it with
an #ifdef ROCKCHIP_TPL to only call it when using the Rockchip
specific RAM init (in the hopes that maybe one day we get our own
RAM init), and then replace existing code for boards like the Rock 5B
so that it no longer reserves these memory banks.

Thank you,
Chris.

> 
> Thanks,
> - Kever
> On 2024/3/27 04:49, Chris Morgan wrote:
> > From: Chris Morgan <macromorgan@hotmail.com>
> > 
> > Add support for parsing the ATAGs created by the Rockchip binary
> > RAM init. This ATAG parsing code was taken from the Rockchip BSP
> > U-Boot source and tested only on parsing the RAM specific ATAGs
> > for the RK3588.
> > 
> > Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> > ---
> >   arch/arm/include/asm/arch-rockchip/atags.h | 222 +++++++++++++++++++++
> >   arch/arm/mach-rockchip/Makefile            |   1 +
> >   arch/arm/mach-rockchip/atags.c             |  99 +++++++++
> >   3 files changed, 322 insertions(+)
> >   create mode 100644 arch/arm/include/asm/arch-rockchip/atags.h
> >   create mode 100644 arch/arm/mach-rockchip/atags.c
> > 
> > diff --git a/arch/arm/include/asm/arch-rockchip/atags.h b/arch/arm/include/asm/arch-rockchip/atags.h
> > new file mode 100644
> > index 0000000000..9bae66d7f8
> > --- /dev/null
> > +++ b/arch/arm/include/asm/arch-rockchip/atags.h
> > @@ -0,0 +1,222 @@
> > +/* SPDX-License-Identifier:     GPL-2.0+ */
> > +/*
> > + * (C) Copyright 2018 Rockchip Electronics Co., Ltd
> > + *
> > + */
> > +
> > +#ifndef __RK_ATAGS_H_
> > +#define __RK_ATAGS_H_
> > +
> > +/* Tag magic */
> > +#define ATAG_CORE		0x54410001
> > +#define ATAG_NONE		0x00000000
> > +
> > +#define ATAG_SERIAL		0x54410050
> > +#define ATAG_BOOTDEV		0x54410051
> > +#define ATAG_DDR_MEM		0x54410052
> > +#define ATAG_TOS_MEM		0x54410053
> > +#define ATAG_RAM_PARTITION	0x54410054
> > +#define ATAG_ATF_MEM		0x54410055
> > +#define ATAG_PUB_KEY		0x54410056
> > +#define ATAG_SOC_INFO		0x54410057
> > +#define ATAG_BOOT1_PARAM	0x54410058
> > +#define ATAG_PSTORE		0x54410059
> > +#define ATAG_FWVER		0x5441005a
> > +#define ATAG_MAX		0x544100ff
> > +
> > +/* Tag size and offset */
> > +#define ATAGS_SIZE		(0x2000)	/* 8K */
> > +#define ATAGS_OFFSET		(0x200000 - ATAGS_SIZE)/* [2M-8K, 2M] */
> > +#define ATAGS_PHYS_BASE		(CFG_SYS_SDRAM_BASE + ATAGS_OFFSET)
> > +
> > +/* tag_fwver.ver[fwid][] */
> > +#define FWVER_LEN		36
> > +
> > +enum fwid {
> > +	FW_DDR,
> > +	FW_SPL,
> > +	FW_ATF,
> > +	FW_TEE,
> > +	FW_MAX,
> > +};
> > +
> > +struct tag_serial {
> > +	u32 version;
> > +	u32 enable;
> > +	u64 addr;
> > +	u32 baudrate;
> > +	u32 m_mode;
> > +	u32 id;
> > +	u32 reserved[2];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_bootdev {
> > +	u32 version;
> > +	u32 devtype;
> > +	u32 devnum;
> > +	u32 mode;
> > +	u32 sdupdate;
> > +	u32 reserved[6];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_ddr_mem {
> > +	u32 count;
> > +	u32 version;
> > +	u64 bank[20];
> > +	u32 flags;
> > +	u32 data[2];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_tos_mem {
> > +	u32 version;
> > +	struct {
> > +		char name[8];
> > +		u64 phy_addr;
> > +		u32 size;
> > +		u32 flags;
> > +	} tee_mem;
> > +
> > +	struct {
> > +		char name[8];
> > +		u64 phy_addr;
> > +		u32 size;
> > +		u32 flags;
> > +	} drm_mem;
> > +
> > +	u64 reserved[7];
> > +	u32 reserved1;
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_atf_mem {
> > +	u32 version;
> > +	u64 phy_addr;
> > +	u32 size;
> > +	u32 flags;
> > +	u32 reserved[2];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_pub_key {
> > +	u32 version;
> > +	u32 len;
> > +	u8  data[768];	/* u32 rsa_n[64], rsa_e[64], rsa_c[64] */
> > +	u32 flag;
> > +	u32 reserved[5];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_ram_partition {
> > +	u32 version;
> > +	u32 count;
> > +	u32 reserved[4];
> > +
> > +	struct {
> > +		char name[16];
> > +		u64 start;
> > +		u64 size;
> > +	} part[6];
> > +
> > +	u32 reserved1[3];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_soc_info {
> > +	u32 version;
> > +	u32 name;	/* Hex: 0x3288, 0x3399... */
> > +	u32 flags;
> > +	u32 reserved[6];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_boot1p {
> > +	u32 version;
> > +	u32 param[8];
> > +	u32 reserved[4];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_pstore {
> > +	u32 version;
> > +	struct {
> > +		u32 addr;
> > +		u32 size;
> > +	} buf[16];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_fwver {
> > +	u32 version;
> > +	char ver[8][FWVER_LEN];
> > +	u32 hash;
> > +} __packed;
> > +
> > +struct tag_core {
> > +	u32 flags;
> > +	u32 pagesize;
> > +	u32 rootdev;
> > +} __packed;
> > +
> > +struct tag_header {
> > +	u32 size;	/* bytes = size * 4 */
> > +	u32 magic;
> > +} __packed;
> > +
> > +/* Must be 4 bytes align */
> > +struct tag {
> > +	struct tag_header hdr;
> > +	union {
> > +		struct tag_core		core;
> > +		struct tag_serial	serial;
> > +		struct tag_bootdev	bootdev;
> > +		struct tag_ddr_mem	ddr_mem;
> > +		struct tag_tos_mem	tos_mem;
> > +		struct tag_ram_partition ram_part;
> > +		struct tag_atf_mem	atf_mem;
> > +		struct tag_pub_key	pub_key;
> > +		struct tag_soc_info	soc;
> > +		struct tag_boot1p	boot1p;
> > +		struct tag_pstore	pstore;
> > +		struct tag_fwver	fwver;
> > +	} u;
> > +} __aligned(4);
> > +
> > +#define tag_next(t)	((struct tag *)((u32 *)(t) + (t)->hdr.size))
> > +#define tag_size(type)	((sizeof(struct tag_header) + sizeof(struct type)) >> 2)
> > +#define for_each_tag(t, base)		\
> > +	for (t = base; t->hdr.size; t = tag_next(t))
> > +
> > +/*
> > + * atags_get_tag - get tag by tag magic
> > + *
> > + * @magic: tag magic, i.e. ATAG_SERIAL, ATAG_BOOTDEV, ...
> > + *
> > + * return: NULL on failed, otherwise return the tag that we want.
> > + */
> > +struct tag *atags_get_tag(u32 magic);
> > +
> > +/*
> > + * atags_is_available - check if atags is available, used for second or
> > + *			later pre-loaders.
> > + *
> > + * return: 0 is not available, otherwise available.
> > + */
> > +int atags_is_available(void);
> > +
> > +/*
> > + * atags_overflow - check if atags is overflow
> > + *
> > + * return: 0 if not overflow, otherwise overflow.
> > + */
> > +int atags_overflow(struct tag *t);
> > +
> > +/*
> > + * atags_bad_magic - check if atags magic is invalid.
> > + *
> > + * return: 1 if invalid, otherwise valid.
> > + */
> > +int atags_bad_magic(u32 magic);
> > +#endif
> > diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
> > index 1dc92066bb..4165cbe99f 100644
> > --- a/arch/arm/mach-rockchip/Makefile
> > +++ b/arch/arm/mach-rockchip/Makefile
> > @@ -28,6 +28,7 @@ endif
> >   ifeq ($(CONFIG_TPL_BUILD),)
> >   obj-$(CONFIG_DISPLAY_CPUINFO) += cpu-info.o
> > +obj-$(CONFIG_ROCKCHIP_RK3588) += atags.o
> >   endif
> >   obj-$(CONFIG_$(SPL_TPL_)RAM) += sdram.o
> > diff --git a/arch/arm/mach-rockchip/atags.c b/arch/arm/mach-rockchip/atags.c
> > new file mode 100644
> > index 0000000000..9daa2f2fc0
> > --- /dev/null
> > +++ b/arch/arm/mach-rockchip/atags.c
> > @@ -0,0 +1,99 @@
> > +// SPDX-License-Identifier:     GPL-2.0+
> > +/*
> > + * (C) Copyright 2018 Rockchip Electronics Co., Ltd.
> > + *
> > + */
> > +
> > +#include <config.h>
> > +#include <asm/io.h>
> > +#include <asm/arch-rockchip/atags.h>
> > +
> > +#define HASH_LEN	sizeof(u32)
> > +
> > +static u32 js_hash(void *buf, u32 len)
> > +{
> > +	u32 i, hash = 0x47C6A7E6;
> > +	char *data = buf;
> > +
> > +	if (!buf || !len)
> > +		return hash;
> > +
> > +	for (i = 0; i < len; i++)
> > +		hash ^= ((hash << 5) + data[i] + (hash >> 2));
> > +
> > +	return hash;
> > +}
> > +
> > +int atags_bad_magic(u32 magic)
> > +{
> > +	bool bad;
> > +
> > +	bad = ((magic != ATAG_CORE) &&
> > +	       (magic != ATAG_NONE) &&
> > +	       (magic < ATAG_SERIAL || magic > ATAG_MAX));
> > +	if (bad)
> > +		printf("Magic(%x) is not support\n", magic);
> > +
> > +	return bad;
> > +}
> > +
> > +static int atags_size_overflow(struct tag *t, u32 tag_size)
> > +{
> > +	return (unsigned long)t + (tag_size << 2) - ATAGS_PHYS_BASE > ATAGS_SIZE;
> > +}
> > +
> > +int atags_overflow(struct tag *t)
> > +{
> > +	bool overflow;
> > +
> > +	overflow = atags_size_overflow(t, 0) ||
> > +		   atags_size_overflow(t, t->hdr.size);
> > +	if (overflow)
> > +		printf("Tag is overflow\n");
> > +
> > +	return overflow;
> > +}
> > +
> > +int atags_is_available(void)
> > +{
> > +	struct tag *t = (struct tag *)ATAGS_PHYS_BASE;
> > +
> > +	return (t->hdr.magic == ATAG_CORE);
> > +}
> > +
> > +struct tag *atags_get_tag(u32 magic)
> > +{
> > +	u32 *hash, calc_hash, size;
> > +	struct tag *t;
> > +
> > +	if (!atags_is_available())
> > +		return NULL;
> > +
> > +	for_each_tag(t, (struct tag *)ATAGS_PHYS_BASE) {
> > +		if (atags_overflow(t))
> > +			return NULL;
> > +
> > +		if (atags_bad_magic(t->hdr.magic))
> > +			return NULL;
> > +
> > +		if (t->hdr.magic != magic)
> > +			continue;
> > +
> > +		size = t->hdr.size;
> > +		hash = (u32 *)((ulong)t + (size << 2) - HASH_LEN);
> > +		if (!*hash) {
> > +			debug("No hash, magic(%x)\n", magic);
> > +			return t;
> > +		}
> > +		calc_hash = js_hash(t, (size << 2) - HASH_LEN);
> > +		if (calc_hash == *hash) {
> > +			debug("Hash okay, magic(%x)\n", magic);
> > +			return t;
> > +		}
> > +		debug("Hash bad, magic(%x), orgHash=%x, nowHash=%x\n",
> > +		      magic, *hash, calc_hash);
> > +		return NULL;
> > +	}
> > +
> > +	return NULL;
> > +}
Eugen Hristev March 27, 2024, 2:21 p.m. UTC | #5
On 3/27/24 15:32, Chris Morgan wrote:
> On Wed, Mar 27, 2024 at 06:32:06PM +0800, Kever Yang wrote:
>> Hi Chris,
>>
>>     The ATAGS is used for passing parameter from bootloader to kernel at
>> first, which has been replaced by DTB now for ARM platform.
>>
>>     And Rockchip using ATAGs for passing parameter like dram memory
>> size/board uart in different boot process like DRAM init binary/ TPL/SPL to
>> U-Boot since 2018.
>>
>>     And almost at the same time, Simon add bloblist for mainline U-Boot
>> which for similar purpose.
>>
>>     So I'm not sure if this ATAGS should be accept in mainline U-Boot or
>> not, even for rockchip platform only seems some kind of regression for this
>> feature support.
>>
>>
>> Hi Simon and Tom,
>>
>>      Could you help to give some suggestion for this?
>>
> 
> I really meant to do this as an "RFC", so I apologize in advance for
> possibly causing more work in treating this as a full-fledged patch.
> 
> The problem I'm trying to solve is that I've got 2 boards, a Rock 5B
> as well as an Indiedroid Nova both with 16GB of RAM. I noticed that
> without the memory holes the Rock 5B defined in my Indiedroid it would
> also fail to boot. I've got 2 other boards as well with less than 16GB
> of RAM which seem to work fine without any holes (a 4GB Indiedroid Nova
> prototype and a GameForce Ace with 12GB of RAM).

Hi,

When I initially added these holes in the memory, I tried to ask Rockchip what are
the holes for. I didn't get any answer, however the patches to reserve the holes
were accepted.
If we could get more information about why the holes are there, if that area is
specific to something, or that it's fixed in a per-SoC basis, we could reserve it
by hardcoding in the Linux DT, without the need for ATAGs.
Without real information, we cannot be sure that for other variants of the SoC or
some other bootrom configuration, the holes will not change/move.

Eugen

> 
> The "RFC" part for which I'm really requesting guidance/comments is
> a question of "is it appropriate to use ATAGS" to get the RAM banks
> on this SoC, or is there a different way we should be doing it? If
> we can/should use the ATAGS, then I guess this can be pared down and
> refactored to just be RK3588 specific. If so, we can possibly add
> something like this to the RK3588 SoC specific code, guard it with
> an #ifdef ROCKCHIP_TPL to only call it when using the Rockchip
> specific RAM init (in the hopes that maybe one day we get our own
> RAM init), and then replace existing code for boards like the Rock 5B
> so that it no longer reserves these memory banks.
> 
> Thank you,
> Chris.
> 
>>
>> Thanks,
>> - Kever
>> On 2024/3/27 04:49, Chris Morgan wrote:
>>> From: Chris Morgan <macromorgan@hotmail.com>
>>>
>>> Add support for parsing the ATAGs created by the Rockchip binary
>>> RAM init. This ATAG parsing code was taken from the Rockchip BSP
>>> U-Boot source and tested only on parsing the RAM specific ATAGs
>>> for the RK3588.
>>>
>>> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
>>> ---
>>>   arch/arm/include/asm/arch-rockchip/atags.h | 222 +++++++++++++++++++++
>>>   arch/arm/mach-rockchip/Makefile            |   1 +
>>>   arch/arm/mach-rockchip/atags.c             |  99 +++++++++
>>>   3 files changed, 322 insertions(+)
>>>   create mode 100644 arch/arm/include/asm/arch-rockchip/atags.h
>>>   create mode 100644 arch/arm/mach-rockchip/atags.c
>>>
>>> diff --git a/arch/arm/include/asm/arch-rockchip/atags.h b/arch/arm/include/asm/arch-rockchip/atags.h
>>> new file mode 100644
>>> index 0000000000..9bae66d7f8
>>> --- /dev/null
>>> +++ b/arch/arm/include/asm/arch-rockchip/atags.h
>>> @@ -0,0 +1,222 @@
>>> +/* SPDX-License-Identifier:     GPL-2.0+ */
>>> +/*
>>> + * (C) Copyright 2018 Rockchip Electronics Co., Ltd
>>> + *
>>> + */
>>> +
>>> +#ifndef __RK_ATAGS_H_
>>> +#define __RK_ATAGS_H_
>>> +
>>> +/* Tag magic */
>>> +#define ATAG_CORE		0x54410001
>>> +#define ATAG_NONE		0x00000000
>>> +
>>> +#define ATAG_SERIAL		0x54410050
>>> +#define ATAG_BOOTDEV		0x54410051
>>> +#define ATAG_DDR_MEM		0x54410052
>>> +#define ATAG_TOS_MEM		0x54410053
>>> +#define ATAG_RAM_PARTITION	0x54410054
>>> +#define ATAG_ATF_MEM		0x54410055
>>> +#define ATAG_PUB_KEY		0x54410056
>>> +#define ATAG_SOC_INFO		0x54410057
>>> +#define ATAG_BOOT1_PARAM	0x54410058
>>> +#define ATAG_PSTORE		0x54410059
>>> +#define ATAG_FWVER		0x5441005a
>>> +#define ATAG_MAX		0x544100ff
>>> +
>>> +/* Tag size and offset */
>>> +#define ATAGS_SIZE		(0x2000)	/* 8K */
>>> +#define ATAGS_OFFSET		(0x200000 - ATAGS_SIZE)/* [2M-8K, 2M] */
>>> +#define ATAGS_PHYS_BASE		(CFG_SYS_SDRAM_BASE + ATAGS_OFFSET)
>>> +
>>> +/* tag_fwver.ver[fwid][] */
>>> +#define FWVER_LEN		36
>>> +
>>> +enum fwid {
>>> +	FW_DDR,
>>> +	FW_SPL,
>>> +	FW_ATF,
>>> +	FW_TEE,
>>> +	FW_MAX,
>>> +};
>>> +
>>> +struct tag_serial {
>>> +	u32 version;
>>> +	u32 enable;
>>> +	u64 addr;
>>> +	u32 baudrate;
>>> +	u32 m_mode;
>>> +	u32 id;
>>> +	u32 reserved[2];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_bootdev {
>>> +	u32 version;
>>> +	u32 devtype;
>>> +	u32 devnum;
>>> +	u32 mode;
>>> +	u32 sdupdate;
>>> +	u32 reserved[6];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_ddr_mem {
>>> +	u32 count;
>>> +	u32 version;
>>> +	u64 bank[20];
>>> +	u32 flags;
>>> +	u32 data[2];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_tos_mem {
>>> +	u32 version;
>>> +	struct {
>>> +		char name[8];
>>> +		u64 phy_addr;
>>> +		u32 size;
>>> +		u32 flags;
>>> +	} tee_mem;
>>> +
>>> +	struct {
>>> +		char name[8];
>>> +		u64 phy_addr;
>>> +		u32 size;
>>> +		u32 flags;
>>> +	} drm_mem;
>>> +
>>> +	u64 reserved[7];
>>> +	u32 reserved1;
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_atf_mem {
>>> +	u32 version;
>>> +	u64 phy_addr;
>>> +	u32 size;
>>> +	u32 flags;
>>> +	u32 reserved[2];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_pub_key {
>>> +	u32 version;
>>> +	u32 len;
>>> +	u8  data[768];	/* u32 rsa_n[64], rsa_e[64], rsa_c[64] */
>>> +	u32 flag;
>>> +	u32 reserved[5];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_ram_partition {
>>> +	u32 version;
>>> +	u32 count;
>>> +	u32 reserved[4];
>>> +
>>> +	struct {
>>> +		char name[16];
>>> +		u64 start;
>>> +		u64 size;
>>> +	} part[6];
>>> +
>>> +	u32 reserved1[3];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_soc_info {
>>> +	u32 version;
>>> +	u32 name;	/* Hex: 0x3288, 0x3399... */
>>> +	u32 flags;
>>> +	u32 reserved[6];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_boot1p {
>>> +	u32 version;
>>> +	u32 param[8];
>>> +	u32 reserved[4];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_pstore {
>>> +	u32 version;
>>> +	struct {
>>> +		u32 addr;
>>> +		u32 size;
>>> +	} buf[16];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_fwver {
>>> +	u32 version;
>>> +	char ver[8][FWVER_LEN];
>>> +	u32 hash;
>>> +} __packed;
>>> +
>>> +struct tag_core {
>>> +	u32 flags;
>>> +	u32 pagesize;
>>> +	u32 rootdev;
>>> +} __packed;
>>> +
>>> +struct tag_header {
>>> +	u32 size;	/* bytes = size * 4 */
>>> +	u32 magic;
>>> +} __packed;
>>> +
>>> +/* Must be 4 bytes align */
>>> +struct tag {
>>> +	struct tag_header hdr;
>>> +	union {
>>> +		struct tag_core		core;
>>> +		struct tag_serial	serial;
>>> +		struct tag_bootdev	bootdev;
>>> +		struct tag_ddr_mem	ddr_mem;
>>> +		struct tag_tos_mem	tos_mem;
>>> +		struct tag_ram_partition ram_part;
>>> +		struct tag_atf_mem	atf_mem;
>>> +		struct tag_pub_key	pub_key;
>>> +		struct tag_soc_info	soc;
>>> +		struct tag_boot1p	boot1p;
>>> +		struct tag_pstore	pstore;
>>> +		struct tag_fwver	fwver;
>>> +	} u;
>>> +} __aligned(4);
>>> +
>>> +#define tag_next(t)	((struct tag *)((u32 *)(t) + (t)->hdr.size))
>>> +#define tag_size(type)	((sizeof(struct tag_header) + sizeof(struct type)) >> 2)
>>> +#define for_each_tag(t, base)		\
>>> +	for (t = base; t->hdr.size; t = tag_next(t))
>>> +
>>> +/*
>>> + * atags_get_tag - get tag by tag magic
>>> + *
>>> + * @magic: tag magic, i.e. ATAG_SERIAL, ATAG_BOOTDEV, ...
>>> + *
>>> + * return: NULL on failed, otherwise return the tag that we want.
>>> + */
>>> +struct tag *atags_get_tag(u32 magic);
>>> +
>>> +/*
>>> + * atags_is_available - check if atags is available, used for second or
>>> + *			later pre-loaders.
>>> + *
>>> + * return: 0 is not available, otherwise available.
>>> + */
>>> +int atags_is_available(void);
>>> +
>>> +/*
>>> + * atags_overflow - check if atags is overflow
>>> + *
>>> + * return: 0 if not overflow, otherwise overflow.
>>> + */
>>> +int atags_overflow(struct tag *t);
>>> +
>>> +/*
>>> + * atags_bad_magic - check if atags magic is invalid.
>>> + *
>>> + * return: 1 if invalid, otherwise valid.
>>> + */
>>> +int atags_bad_magic(u32 magic);
>>> +#endif
>>> diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
>>> index 1dc92066bb..4165cbe99f 100644
>>> --- a/arch/arm/mach-rockchip/Makefile
>>> +++ b/arch/arm/mach-rockchip/Makefile
>>> @@ -28,6 +28,7 @@ endif
>>>   ifeq ($(CONFIG_TPL_BUILD),)
>>>   obj-$(CONFIG_DISPLAY_CPUINFO) += cpu-info.o
>>> +obj-$(CONFIG_ROCKCHIP_RK3588) += atags.o
>>>   endif
>>>   obj-$(CONFIG_$(SPL_TPL_)RAM) += sdram.o
>>> diff --git a/arch/arm/mach-rockchip/atags.c b/arch/arm/mach-rockchip/atags.c
>>> new file mode 100644
>>> index 0000000000..9daa2f2fc0
>>> --- /dev/null
>>> +++ b/arch/arm/mach-rockchip/atags.c
>>> @@ -0,0 +1,99 @@
>>> +// SPDX-License-Identifier:     GPL-2.0+
>>> +/*
>>> + * (C) Copyright 2018 Rockchip Electronics Co., Ltd.
>>> + *
>>> + */
>>> +
>>> +#include <config.h>
>>> +#include <asm/io.h>
>>> +#include <asm/arch-rockchip/atags.h>
>>> +
>>> +#define HASH_LEN	sizeof(u32)
>>> +
>>> +static u32 js_hash(void *buf, u32 len)
>>> +{
>>> +	u32 i, hash = 0x47C6A7E6;
>>> +	char *data = buf;
>>> +
>>> +	if (!buf || !len)
>>> +		return hash;
>>> +
>>> +	for (i = 0; i < len; i++)
>>> +		hash ^= ((hash << 5) + data[i] + (hash >> 2));
>>> +
>>> +	return hash;
>>> +}
>>> +
>>> +int atags_bad_magic(u32 magic)
>>> +{
>>> +	bool bad;
>>> +
>>> +	bad = ((magic != ATAG_CORE) &&
>>> +	       (magic != ATAG_NONE) &&
>>> +	       (magic < ATAG_SERIAL || magic > ATAG_MAX));
>>> +	if (bad)
>>> +		printf("Magic(%x) is not support\n", magic);
>>> +
>>> +	return bad;
>>> +}
>>> +
>>> +static int atags_size_overflow(struct tag *t, u32 tag_size)
>>> +{
>>> +	return (unsigned long)t + (tag_size << 2) - ATAGS_PHYS_BASE > ATAGS_SIZE;
>>> +}
>>> +
>>> +int atags_overflow(struct tag *t)
>>> +{
>>> +	bool overflow;
>>> +
>>> +	overflow = atags_size_overflow(t, 0) ||
>>> +		   atags_size_overflow(t, t->hdr.size);
>>> +	if (overflow)
>>> +		printf("Tag is overflow\n");
>>> +
>>> +	return overflow;
>>> +}
>>> +
>>> +int atags_is_available(void)
>>> +{
>>> +	struct tag *t = (struct tag *)ATAGS_PHYS_BASE;
>>> +
>>> +	return (t->hdr.magic == ATAG_CORE);
>>> +}
>>> +
>>> +struct tag *atags_get_tag(u32 magic)
>>> +{
>>> +	u32 *hash, calc_hash, size;
>>> +	struct tag *t;
>>> +
>>> +	if (!atags_is_available())
>>> +		return NULL;
>>> +
>>> +	for_each_tag(t, (struct tag *)ATAGS_PHYS_BASE) {
>>> +		if (atags_overflow(t))
>>> +			return NULL;
>>> +
>>> +		if (atags_bad_magic(t->hdr.magic))
>>> +			return NULL;
>>> +
>>> +		if (t->hdr.magic != magic)
>>> +			continue;
>>> +
>>> +		size = t->hdr.size;
>>> +		hash = (u32 *)((ulong)t + (size << 2) - HASH_LEN);
>>> +		if (!*hash) {
>>> +			debug("No hash, magic(%x)\n", magic);
>>> +			return t;
>>> +		}
>>> +		calc_hash = js_hash(t, (size << 2) - HASH_LEN);
>>> +		if (calc_hash == *hash) {
>>> +			debug("Hash okay, magic(%x)\n", magic);
>>> +			return t;
>>> +		}
>>> +		debug("Hash bad, magic(%x), orgHash=%x, nowHash=%x\n",
>>> +		      magic, *hash, calc_hash);
>>> +		return NULL;
>>> +	}
>>> +
>>> +	return NULL;
>>> +}
Chris Morgan March 27, 2024, 3:03 p.m. UTC | #6
On Wed, Mar 27, 2024 at 04:21:49PM +0200, Eugen Hristev wrote:
> On 3/27/24 15:32, Chris Morgan wrote:
> > On Wed, Mar 27, 2024 at 06:32:06PM +0800, Kever Yang wrote:
> >> Hi Chris,
> >>
> >>     The ATAGS is used for passing parameter from bootloader to kernel at
> >> first, which has been replaced by DTB now for ARM platform.
> >>
> >>     And Rockchip using ATAGs for passing parameter like dram memory
> >> size/board uart in different boot process like DRAM init binary/ TPL/SPL to
> >> U-Boot since 2018.
> >>
> >>     And almost at the same time, Simon add bloblist for mainline U-Boot
> >> which for similar purpose.
> >>
> >>     So I'm not sure if this ATAGS should be accept in mainline U-Boot or
> >> not, even for rockchip platform only seems some kind of regression for this
> >> feature support.
> >>
> >>
> >> Hi Simon and Tom,
> >>
> >>      Could you help to give some suggestion for this?
> >>
> > 
> > I really meant to do this as an "RFC", so I apologize in advance for
> > possibly causing more work in treating this as a full-fledged patch.
> > 
> > The problem I'm trying to solve is that I've got 2 boards, a Rock 5B
> > as well as an Indiedroid Nova both with 16GB of RAM. I noticed that
> > without the memory holes the Rock 5B defined in my Indiedroid it would
> > also fail to boot. I've got 2 other boards as well with less than 16GB
> > of RAM which seem to work fine without any holes (a 4GB Indiedroid Nova
> > prototype and a GameForce Ace with 12GB of RAM).
> 
> Hi,
> 
> When I initially added these holes in the memory, I tried to ask Rockchip what are
> the holes for. I didn't get any answer, however the patches to reserve the holes
> were accepted.
> If we could get more information about why the holes are there, if that area is
> specific to something, or that it's fixed in a per-SoC basis, we could reserve it
> by hardcoding in the Linux DT, without the need for ATAGs.
> Without real information, we cannot be sure that for other variants of the SoC or
> some other bootrom configuration, the holes will not change/move.
> 
> Eugen

It's not *just* about the holes, but also making sure we use the full
extent of the RAM. For example on my 4GB Indiedroid Nova the existing
logic ignores about 256MB of RAM that's otherwise present. When we
use the existing code the RAM map reported by Linux is as follows:

[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000000200000-0x00000000efffffff]

Whereas when we do ATAGS parsing to set the banks we get the following:

[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000000200000-0x00000000efffffff]
[    0.000000]   node   0: [mem 0x00000001f0000000-0x00000001ffffffff]

So basically the issue is two-fold... one we need to create the memory
holes when necessary, and two the current method of defining memory
banks leaves some RAM unallocated. Parsing the ATAGS does both of these,
I'm just curious if it's the RIGHT way or there's something else I'm
missing...

Thank you,
Chris.

> 
> > 
> > The "RFC" part for which I'm really requesting guidance/comments is
> > a question of "is it appropriate to use ATAGS" to get the RAM banks
> > on this SoC, or is there a different way we should be doing it? If
> > we can/should use the ATAGS, then I guess this can be pared down and
> > refactored to just be RK3588 specific. If so, we can possibly add
> > something like this to the RK3588 SoC specific code, guard it with
> > an #ifdef ROCKCHIP_TPL to only call it when using the Rockchip
> > specific RAM init (in the hopes that maybe one day we get our own
> > RAM init), and then replace existing code for boards like the Rock 5B
> > so that it no longer reserves these memory banks.
> > 
> > Thank you,
> > Chris.
> > 
> >>
> >> Thanks,
> >> - Kever
> >> On 2024/3/27 04:49, Chris Morgan wrote:
> >>> From: Chris Morgan <macromorgan@hotmail.com>
> >>>
> >>> Add support for parsing the ATAGs created by the Rockchip binary
> >>> RAM init. This ATAG parsing code was taken from the Rockchip BSP
> >>> U-Boot source and tested only on parsing the RAM specific ATAGs
> >>> for the RK3588.
> >>>
> >>> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> >>> ---
> >>>   arch/arm/include/asm/arch-rockchip/atags.h | 222 +++++++++++++++++++++
> >>>   arch/arm/mach-rockchip/Makefile            |   1 +
> >>>   arch/arm/mach-rockchip/atags.c             |  99 +++++++++
> >>>   3 files changed, 322 insertions(+)
> >>>   create mode 100644 arch/arm/include/asm/arch-rockchip/atags.h
> >>>   create mode 100644 arch/arm/mach-rockchip/atags.c
> >>>
> >>> diff --git a/arch/arm/include/asm/arch-rockchip/atags.h b/arch/arm/include/asm/arch-rockchip/atags.h
> >>> new file mode 100644
> >>> index 0000000000..9bae66d7f8
> >>> --- /dev/null
> >>> +++ b/arch/arm/include/asm/arch-rockchip/atags.h
> >>> @@ -0,0 +1,222 @@
> >>> +/* SPDX-License-Identifier:     GPL-2.0+ */
> >>> +/*
> >>> + * (C) Copyright 2018 Rockchip Electronics Co., Ltd
> >>> + *
> >>> + */
> >>> +
> >>> +#ifndef __RK_ATAGS_H_
> >>> +#define __RK_ATAGS_H_
> >>> +
> >>> +/* Tag magic */
> >>> +#define ATAG_CORE		0x54410001
> >>> +#define ATAG_NONE		0x00000000
> >>> +
> >>> +#define ATAG_SERIAL		0x54410050
> >>> +#define ATAG_BOOTDEV		0x54410051
> >>> +#define ATAG_DDR_MEM		0x54410052
> >>> +#define ATAG_TOS_MEM		0x54410053
> >>> +#define ATAG_RAM_PARTITION	0x54410054
> >>> +#define ATAG_ATF_MEM		0x54410055
> >>> +#define ATAG_PUB_KEY		0x54410056
> >>> +#define ATAG_SOC_INFO		0x54410057
> >>> +#define ATAG_BOOT1_PARAM	0x54410058
> >>> +#define ATAG_PSTORE		0x54410059
> >>> +#define ATAG_FWVER		0x5441005a
> >>> +#define ATAG_MAX		0x544100ff
> >>> +
> >>> +/* Tag size and offset */
> >>> +#define ATAGS_SIZE		(0x2000)	/* 8K */
> >>> +#define ATAGS_OFFSET		(0x200000 - ATAGS_SIZE)/* [2M-8K, 2M] */
> >>> +#define ATAGS_PHYS_BASE		(CFG_SYS_SDRAM_BASE + ATAGS_OFFSET)
> >>> +
> >>> +/* tag_fwver.ver[fwid][] */
> >>> +#define FWVER_LEN		36
> >>> +
> >>> +enum fwid {
> >>> +	FW_DDR,
> >>> +	FW_SPL,
> >>> +	FW_ATF,
> >>> +	FW_TEE,
> >>> +	FW_MAX,
> >>> +};
> >>> +
> >>> +struct tag_serial {
> >>> +	u32 version;
> >>> +	u32 enable;
> >>> +	u64 addr;
> >>> +	u32 baudrate;
> >>> +	u32 m_mode;
> >>> +	u32 id;
> >>> +	u32 reserved[2];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_bootdev {
> >>> +	u32 version;
> >>> +	u32 devtype;
> >>> +	u32 devnum;
> >>> +	u32 mode;
> >>> +	u32 sdupdate;
> >>> +	u32 reserved[6];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_ddr_mem {
> >>> +	u32 count;
> >>> +	u32 version;
> >>> +	u64 bank[20];
> >>> +	u32 flags;
> >>> +	u32 data[2];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_tos_mem {
> >>> +	u32 version;
> >>> +	struct {
> >>> +		char name[8];
> >>> +		u64 phy_addr;
> >>> +		u32 size;
> >>> +		u32 flags;
> >>> +	} tee_mem;
> >>> +
> >>> +	struct {
> >>> +		char name[8];
> >>> +		u64 phy_addr;
> >>> +		u32 size;
> >>> +		u32 flags;
> >>> +	} drm_mem;
> >>> +
> >>> +	u64 reserved[7];
> >>> +	u32 reserved1;
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_atf_mem {
> >>> +	u32 version;
> >>> +	u64 phy_addr;
> >>> +	u32 size;
> >>> +	u32 flags;
> >>> +	u32 reserved[2];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_pub_key {
> >>> +	u32 version;
> >>> +	u32 len;
> >>> +	u8  data[768];	/* u32 rsa_n[64], rsa_e[64], rsa_c[64] */
> >>> +	u32 flag;
> >>> +	u32 reserved[5];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_ram_partition {
> >>> +	u32 version;
> >>> +	u32 count;
> >>> +	u32 reserved[4];
> >>> +
> >>> +	struct {
> >>> +		char name[16];
> >>> +		u64 start;
> >>> +		u64 size;
> >>> +	} part[6];
> >>> +
> >>> +	u32 reserved1[3];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_soc_info {
> >>> +	u32 version;
> >>> +	u32 name;	/* Hex: 0x3288, 0x3399... */
> >>> +	u32 flags;
> >>> +	u32 reserved[6];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_boot1p {
> >>> +	u32 version;
> >>> +	u32 param[8];
> >>> +	u32 reserved[4];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_pstore {
> >>> +	u32 version;
> >>> +	struct {
> >>> +		u32 addr;
> >>> +		u32 size;
> >>> +	} buf[16];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_fwver {
> >>> +	u32 version;
> >>> +	char ver[8][FWVER_LEN];
> >>> +	u32 hash;
> >>> +} __packed;
> >>> +
> >>> +struct tag_core {
> >>> +	u32 flags;
> >>> +	u32 pagesize;
> >>> +	u32 rootdev;
> >>> +} __packed;
> >>> +
> >>> +struct tag_header {
> >>> +	u32 size;	/* bytes = size * 4 */
> >>> +	u32 magic;
> >>> +} __packed;
> >>> +
> >>> +/* Must be 4 bytes align */
> >>> +struct tag {
> >>> +	struct tag_header hdr;
> >>> +	union {
> >>> +		struct tag_core		core;
> >>> +		struct tag_serial	serial;
> >>> +		struct tag_bootdev	bootdev;
> >>> +		struct tag_ddr_mem	ddr_mem;
> >>> +		struct tag_tos_mem	tos_mem;
> >>> +		struct tag_ram_partition ram_part;
> >>> +		struct tag_atf_mem	atf_mem;
> >>> +		struct tag_pub_key	pub_key;
> >>> +		struct tag_soc_info	soc;
> >>> +		struct tag_boot1p	boot1p;
> >>> +		struct tag_pstore	pstore;
> >>> +		struct tag_fwver	fwver;
> >>> +	} u;
> >>> +} __aligned(4);
> >>> +
> >>> +#define tag_next(t)	((struct tag *)((u32 *)(t) + (t)->hdr.size))
> >>> +#define tag_size(type)	((sizeof(struct tag_header) + sizeof(struct type)) >> 2)
> >>> +#define for_each_tag(t, base)		\
> >>> +	for (t = base; t->hdr.size; t = tag_next(t))
> >>> +
> >>> +/*
> >>> + * atags_get_tag - get tag by tag magic
> >>> + *
> >>> + * @magic: tag magic, i.e. ATAG_SERIAL, ATAG_BOOTDEV, ...
> >>> + *
> >>> + * return: NULL on failed, otherwise return the tag that we want.
> >>> + */
> >>> +struct tag *atags_get_tag(u32 magic);
> >>> +
> >>> +/*
> >>> + * atags_is_available - check if atags is available, used for second or
> >>> + *			later pre-loaders.
> >>> + *
> >>> + * return: 0 is not available, otherwise available.
> >>> + */
> >>> +int atags_is_available(void);
> >>> +
> >>> +/*
> >>> + * atags_overflow - check if atags is overflow
> >>> + *
> >>> + * return: 0 if not overflow, otherwise overflow.
> >>> + */
> >>> +int atags_overflow(struct tag *t);
> >>> +
> >>> +/*
> >>> + * atags_bad_magic - check if atags magic is invalid.
> >>> + *
> >>> + * return: 1 if invalid, otherwise valid.
> >>> + */
> >>> +int atags_bad_magic(u32 magic);
> >>> +#endif
> >>> diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
> >>> index 1dc92066bb..4165cbe99f 100644
> >>> --- a/arch/arm/mach-rockchip/Makefile
> >>> +++ b/arch/arm/mach-rockchip/Makefile
> >>> @@ -28,6 +28,7 @@ endif
> >>>   ifeq ($(CONFIG_TPL_BUILD),)
> >>>   obj-$(CONFIG_DISPLAY_CPUINFO) += cpu-info.o
> >>> +obj-$(CONFIG_ROCKCHIP_RK3588) += atags.o
> >>>   endif
> >>>   obj-$(CONFIG_$(SPL_TPL_)RAM) += sdram.o
> >>> diff --git a/arch/arm/mach-rockchip/atags.c b/arch/arm/mach-rockchip/atags.c
> >>> new file mode 100644
> >>> index 0000000000..9daa2f2fc0
> >>> --- /dev/null
> >>> +++ b/arch/arm/mach-rockchip/atags.c
> >>> @@ -0,0 +1,99 @@
> >>> +// SPDX-License-Identifier:     GPL-2.0+
> >>> +/*
> >>> + * (C) Copyright 2018 Rockchip Electronics Co., Ltd.
> >>> + *
> >>> + */
> >>> +
> >>> +#include <config.h>
> >>> +#include <asm/io.h>
> >>> +#include <asm/arch-rockchip/atags.h>
> >>> +
> >>> +#define HASH_LEN	sizeof(u32)
> >>> +
> >>> +static u32 js_hash(void *buf, u32 len)
> >>> +{
> >>> +	u32 i, hash = 0x47C6A7E6;
> >>> +	char *data = buf;
> >>> +
> >>> +	if (!buf || !len)
> >>> +		return hash;
> >>> +
> >>> +	for (i = 0; i < len; i++)
> >>> +		hash ^= ((hash << 5) + data[i] + (hash >> 2));
> >>> +
> >>> +	return hash;
> >>> +}
> >>> +
> >>> +int atags_bad_magic(u32 magic)
> >>> +{
> >>> +	bool bad;
> >>> +
> >>> +	bad = ((magic != ATAG_CORE) &&
> >>> +	       (magic != ATAG_NONE) &&
> >>> +	       (magic < ATAG_SERIAL || magic > ATAG_MAX));
> >>> +	if (bad)
> >>> +		printf("Magic(%x) is not support\n", magic);
> >>> +
> >>> +	return bad;
> >>> +}
> >>> +
> >>> +static int atags_size_overflow(struct tag *t, u32 tag_size)
> >>> +{
> >>> +	return (unsigned long)t + (tag_size << 2) - ATAGS_PHYS_BASE > ATAGS_SIZE;
> >>> +}
> >>> +
> >>> +int atags_overflow(struct tag *t)
> >>> +{
> >>> +	bool overflow;
> >>> +
> >>> +	overflow = atags_size_overflow(t, 0) ||
> >>> +		   atags_size_overflow(t, t->hdr.size);
> >>> +	if (overflow)
> >>> +		printf("Tag is overflow\n");
> >>> +
> >>> +	return overflow;
> >>> +}
> >>> +
> >>> +int atags_is_available(void)
> >>> +{
> >>> +	struct tag *t = (struct tag *)ATAGS_PHYS_BASE;
> >>> +
> >>> +	return (t->hdr.magic == ATAG_CORE);
> >>> +}
> >>> +
> >>> +struct tag *atags_get_tag(u32 magic)
> >>> +{
> >>> +	u32 *hash, calc_hash, size;
> >>> +	struct tag *t;
> >>> +
> >>> +	if (!atags_is_available())
> >>> +		return NULL;
> >>> +
> >>> +	for_each_tag(t, (struct tag *)ATAGS_PHYS_BASE) {
> >>> +		if (atags_overflow(t))
> >>> +			return NULL;
> >>> +
> >>> +		if (atags_bad_magic(t->hdr.magic))
> >>> +			return NULL;
> >>> +
> >>> +		if (t->hdr.magic != magic)
> >>> +			continue;
> >>> +
> >>> +		size = t->hdr.size;
> >>> +		hash = (u32 *)((ulong)t + (size << 2) - HASH_LEN);
> >>> +		if (!*hash) {
> >>> +			debug("No hash, magic(%x)\n", magic);
> >>> +			return t;
> >>> +		}
> >>> +		calc_hash = js_hash(t, (size << 2) - HASH_LEN);
> >>> +		if (calc_hash == *hash) {
> >>> +			debug("Hash okay, magic(%x)\n", magic);
> >>> +			return t;
> >>> +		}
> >>> +		debug("Hash bad, magic(%x), orgHash=%x, nowHash=%x\n",
> >>> +		      magic, *hash, calc_hash);
> >>> +		return NULL;
> >>> +	}
> >>> +
> >>> +	return NULL;
> >>> +}
>
Tom Rini March 28, 2024, 8:02 p.m. UTC | #7
On Wed, Mar 27, 2024 at 10:03:11AM -0500, Chris Morgan wrote:
> On Wed, Mar 27, 2024 at 04:21:49PM +0200, Eugen Hristev wrote:
> > On 3/27/24 15:32, Chris Morgan wrote:
> > > On Wed, Mar 27, 2024 at 06:32:06PM +0800, Kever Yang wrote:
> > >> Hi Chris,
> > >>
> > >>     The ATAGS is used for passing parameter from bootloader to kernel at
> > >> first, which has been replaced by DTB now for ARM platform.
> > >>
> > >>     And Rockchip using ATAGs for passing parameter like dram memory
> > >> size/board uart in different boot process like DRAM init binary/ TPL/SPL to
> > >> U-Boot since 2018.
> > >>
> > >>     And almost at the same time, Simon add bloblist for mainline U-Boot
> > >> which for similar purpose.
> > >>
> > >>     So I'm not sure if this ATAGS should be accept in mainline U-Boot or
> > >> not, even for rockchip platform only seems some kind of regression for this
> > >> feature support.
> > >>
> > >>
> > >> Hi Simon and Tom,
> > >>
> > >>      Could you help to give some suggestion for this?
> > >>
> > > 
> > > I really meant to do this as an "RFC", so I apologize in advance for
> > > possibly causing more work in treating this as a full-fledged patch.
> > > 
> > > The problem I'm trying to solve is that I've got 2 boards, a Rock 5B
> > > as well as an Indiedroid Nova both with 16GB of RAM. I noticed that
> > > without the memory holes the Rock 5B defined in my Indiedroid it would
> > > also fail to boot. I've got 2 other boards as well with less than 16GB
> > > of RAM which seem to work fine without any holes (a 4GB Indiedroid Nova
> > > prototype and a GameForce Ace with 12GB of RAM).
> > 
> > Hi,
> > 
> > When I initially added these holes in the memory, I tried to ask Rockchip what are
> > the holes for. I didn't get any answer, however the patches to reserve the holes
> > were accepted.
> > If we could get more information about why the holes are there, if that area is
> > specific to something, or that it's fixed in a per-SoC basis, we could reserve it
> > by hardcoding in the Linux DT, without the need for ATAGs.
> > Without real information, we cannot be sure that for other variants of the SoC or
> > some other bootrom configuration, the holes will not change/move.
> > 
> > Eugen
> 
> It's not *just* about the holes, but also making sure we use the full
> extent of the RAM. For example on my 4GB Indiedroid Nova the existing
> logic ignores about 256MB of RAM that's otherwise present. When we
> use the existing code the RAM map reported by Linux is as follows:
> 
> [    0.000000] Early memory node ranges
> [    0.000000]   node   0: [mem 0x0000000000200000-0x00000000efffffff]
> 
> Whereas when we do ATAGS parsing to set the banks we get the following:
> 
> [    0.000000] Early memory node ranges
> [    0.000000]   node   0: [mem 0x0000000000200000-0x00000000efffffff]
> [    0.000000]   node   0: [mem 0x00000001f0000000-0x00000001ffffffff]
> 
> So basically the issue is two-fold... one we need to create the memory
> holes when necessary, and two the current method of defining memory
> banks leaves some RAM unallocated. Parsing the ATAGS does both of these,
> I'm just curious if it's the RIGHT way or there's something else I'm
> missing...

It's unfortunate that all of this is in the wild, from the Rockchip
side. The best answer is that the platform should be passing all of this
along via bloblist. I would hope that future platforms will do that. For
now yes, I guess we need to constrain this ATAG parsing to rockchip as
much as we can and use it.
Chris Morgan March 28, 2024, 9:58 p.m. UTC | #8
On Thu, Mar 28, 2024 at 04:02:09PM -0400, Tom Rini wrote:
> On Wed, Mar 27, 2024 at 10:03:11AM -0500, Chris Morgan wrote:
> > On Wed, Mar 27, 2024 at 04:21:49PM +0200, Eugen Hristev wrote:
> > > On 3/27/24 15:32, Chris Morgan wrote:
> > > > On Wed, Mar 27, 2024 at 06:32:06PM +0800, Kever Yang wrote:
> > > >> Hi Chris,
> > > >>
> > > >>     The ATAGS is used for passing parameter from bootloader to kernel at
> > > >> first, which has been replaced by DTB now for ARM platform.
> > > >>
> > > >>     And Rockchip using ATAGs for passing parameter like dram memory
> > > >> size/board uart in different boot process like DRAM init binary/ TPL/SPL to
> > > >> U-Boot since 2018.
> > > >>
> > > >>     And almost at the same time, Simon add bloblist for mainline U-Boot
> > > >> which for similar purpose.
> > > >>
> > > >>     So I'm not sure if this ATAGS should be accept in mainline U-Boot or
> > > >> not, even for rockchip platform only seems some kind of regression for this
> > > >> feature support.
> > > >>
> > > >>
> > > >> Hi Simon and Tom,
> > > >>
> > > >>      Could you help to give some suggestion for this?
> > > >>
> > > > 
> > > > I really meant to do this as an "RFC", so I apologize in advance for
> > > > possibly causing more work in treating this as a full-fledged patch.
> > > > 
> > > > The problem I'm trying to solve is that I've got 2 boards, a Rock 5B
> > > > as well as an Indiedroid Nova both with 16GB of RAM. I noticed that
> > > > without the memory holes the Rock 5B defined in my Indiedroid it would
> > > > also fail to boot. I've got 2 other boards as well with less than 16GB
> > > > of RAM which seem to work fine without any holes (a 4GB Indiedroid Nova
> > > > prototype and a GameForce Ace with 12GB of RAM).
> > > 
> > > Hi,
> > > 
> > > When I initially added these holes in the memory, I tried to ask Rockchip what are
> > > the holes for. I didn't get any answer, however the patches to reserve the holes
> > > were accepted.
> > > If we could get more information about why the holes are there, if that area is
> > > specific to something, or that it's fixed in a per-SoC basis, we could reserve it
> > > by hardcoding in the Linux DT, without the need for ATAGs.
> > > Without real information, we cannot be sure that for other variants of the SoC or
> > > some other bootrom configuration, the holes will not change/move.
> > > 
> > > Eugen
> > 
> > It's not *just* about the holes, but also making sure we use the full
> > extent of the RAM. For example on my 4GB Indiedroid Nova the existing
> > logic ignores about 256MB of RAM that's otherwise present. When we
> > use the existing code the RAM map reported by Linux is as follows:
> > 
> > [    0.000000] Early memory node ranges
> > [    0.000000]   node   0: [mem 0x0000000000200000-0x00000000efffffff]
> > 
> > Whereas when we do ATAGS parsing to set the banks we get the following:
> > 
> > [    0.000000] Early memory node ranges
> > [    0.000000]   node   0: [mem 0x0000000000200000-0x00000000efffffff]
> > [    0.000000]   node   0: [mem 0x00000001f0000000-0x00000001ffffffff]
> > 
> > So basically the issue is two-fold... one we need to create the memory
> > holes when necessary, and two the current method of defining memory
> > banks leaves some RAM unallocated. Parsing the ATAGS does both of these,
> > I'm just curious if it's the RIGHT way or there's something else I'm
> > missing...
> 
> It's unfortunate that all of this is in the wild, from the Rockchip
> side. The best answer is that the platform should be passing all of this
> along via bloblist. I would hope that future platforms will do that. For
> now yes, I guess we need to constrain this ATAG parsing to rockchip as
> much as we can and use it.

Any thought/benefit of trying to force the ATAGS into a bloblist after the
fact (instead of expecting it to be passed that way)?  Otherwise yes I'll
work on simplified ATAGS parsing for the memory info and constrain it to
the rk3588 specific board code/wrap it around ROCKCHIP_TPL present.

Thank you,
Chris

> 
> -- 
> Tom
Tom Rini March 28, 2024, 10:13 p.m. UTC | #9
On Thu, Mar 28, 2024 at 04:58:53PM -0500, Chris Morgan wrote:
> On Thu, Mar 28, 2024 at 04:02:09PM -0400, Tom Rini wrote:
> > On Wed, Mar 27, 2024 at 10:03:11AM -0500, Chris Morgan wrote:
> > > On Wed, Mar 27, 2024 at 04:21:49PM +0200, Eugen Hristev wrote:
> > > > On 3/27/24 15:32, Chris Morgan wrote:
> > > > > On Wed, Mar 27, 2024 at 06:32:06PM +0800, Kever Yang wrote:
> > > > >> Hi Chris,
> > > > >>
> > > > >>     The ATAGS is used for passing parameter from bootloader to kernel at
> > > > >> first, which has been replaced by DTB now for ARM platform.
> > > > >>
> > > > >>     And Rockchip using ATAGs for passing parameter like dram memory
> > > > >> size/board uart in different boot process like DRAM init binary/ TPL/SPL to
> > > > >> U-Boot since 2018.
> > > > >>
> > > > >>     And almost at the same time, Simon add bloblist for mainline U-Boot
> > > > >> which for similar purpose.
> > > > >>
> > > > >>     So I'm not sure if this ATAGS should be accept in mainline U-Boot or
> > > > >> not, even for rockchip platform only seems some kind of regression for this
> > > > >> feature support.
> > > > >>
> > > > >>
> > > > >> Hi Simon and Tom,
> > > > >>
> > > > >>      Could you help to give some suggestion for this?
> > > > >>
> > > > > 
> > > > > I really meant to do this as an "RFC", so I apologize in advance for
> > > > > possibly causing more work in treating this as a full-fledged patch.
> > > > > 
> > > > > The problem I'm trying to solve is that I've got 2 boards, a Rock 5B
> > > > > as well as an Indiedroid Nova both with 16GB of RAM. I noticed that
> > > > > without the memory holes the Rock 5B defined in my Indiedroid it would
> > > > > also fail to boot. I've got 2 other boards as well with less than 16GB
> > > > > of RAM which seem to work fine without any holes (a 4GB Indiedroid Nova
> > > > > prototype and a GameForce Ace with 12GB of RAM).
> > > > 
> > > > Hi,
> > > > 
> > > > When I initially added these holes in the memory, I tried to ask Rockchip what are
> > > > the holes for. I didn't get any answer, however the patches to reserve the holes
> > > > were accepted.
> > > > If we could get more information about why the holes are there, if that area is
> > > > specific to something, or that it's fixed in a per-SoC basis, we could reserve it
> > > > by hardcoding in the Linux DT, without the need for ATAGs.
> > > > Without real information, we cannot be sure that for other variants of the SoC or
> > > > some other bootrom configuration, the holes will not change/move.
> > > > 
> > > > Eugen
> > > 
> > > It's not *just* about the holes, but also making sure we use the full
> > > extent of the RAM. For example on my 4GB Indiedroid Nova the existing
> > > logic ignores about 256MB of RAM that's otherwise present. When we
> > > use the existing code the RAM map reported by Linux is as follows:
> > > 
> > > [    0.000000] Early memory node ranges
> > > [    0.000000]   node   0: [mem 0x0000000000200000-0x00000000efffffff]
> > > 
> > > Whereas when we do ATAGS parsing to set the banks we get the following:
> > > 
> > > [    0.000000] Early memory node ranges
> > > [    0.000000]   node   0: [mem 0x0000000000200000-0x00000000efffffff]
> > > [    0.000000]   node   0: [mem 0x00000001f0000000-0x00000001ffffffff]
> > > 
> > > So basically the issue is two-fold... one we need to create the memory
> > > holes when necessary, and two the current method of defining memory
> > > banks leaves some RAM unallocated. Parsing the ATAGS does both of these,
> > > I'm just curious if it's the RIGHT way or there's something else I'm
> > > missing...
> > 
> > It's unfortunate that all of this is in the wild, from the Rockchip
> > side. The best answer is that the platform should be passing all of this
> > along via bloblist. I would hope that future platforms will do that. For
> > now yes, I guess we need to constrain this ATAG parsing to rockchip as
> > much as we can and use it.
> 
> Any thought/benefit of trying to force the ATAGS into a bloblist after the
> fact (instead of expecting it to be passed that way)?  Otherwise yes I'll
> work on simplified ATAGS parsing for the memory info and constrain it to
> the rk3588 specific board code/wrap it around ROCKCHIP_TPL present.

I don't think it's worth the code size to convert the ATAGS to bloblist
at this time. In the future when we have rockchip platforms that pass
bloblist natively at that point it might make sense to convert the ATAGS
instead.
diff mbox series

Patch

diff --git a/arch/arm/include/asm/arch-rockchip/atags.h b/arch/arm/include/asm/arch-rockchip/atags.h
new file mode 100644
index 0000000000..9bae66d7f8
--- /dev/null
+++ b/arch/arm/include/asm/arch-rockchip/atags.h
@@ -0,0 +1,222 @@ 
+/* SPDX-License-Identifier:     GPL-2.0+ */
+/*
+ * (C) Copyright 2018 Rockchip Electronics Co., Ltd
+ *
+ */
+
+#ifndef __RK_ATAGS_H_
+#define __RK_ATAGS_H_
+
+/* Tag magic */
+#define ATAG_CORE		0x54410001
+#define ATAG_NONE		0x00000000
+
+#define ATAG_SERIAL		0x54410050
+#define ATAG_BOOTDEV		0x54410051
+#define ATAG_DDR_MEM		0x54410052
+#define ATAG_TOS_MEM		0x54410053
+#define ATAG_RAM_PARTITION	0x54410054
+#define ATAG_ATF_MEM		0x54410055
+#define ATAG_PUB_KEY		0x54410056
+#define ATAG_SOC_INFO		0x54410057
+#define ATAG_BOOT1_PARAM	0x54410058
+#define ATAG_PSTORE		0x54410059
+#define ATAG_FWVER		0x5441005a
+#define ATAG_MAX		0x544100ff
+
+/* Tag size and offset */
+#define ATAGS_SIZE		(0x2000)	/* 8K */
+#define ATAGS_OFFSET		(0x200000 - ATAGS_SIZE)/* [2M-8K, 2M] */
+#define ATAGS_PHYS_BASE		(CFG_SYS_SDRAM_BASE + ATAGS_OFFSET)
+
+/* tag_fwver.ver[fwid][] */
+#define FWVER_LEN		36
+
+enum fwid {
+	FW_DDR,
+	FW_SPL,
+	FW_ATF,
+	FW_TEE,
+	FW_MAX,
+};
+
+struct tag_serial {
+	u32 version;
+	u32 enable;
+	u64 addr;
+	u32 baudrate;
+	u32 m_mode;
+	u32 id;
+	u32 reserved[2];
+	u32 hash;
+} __packed;
+
+struct tag_bootdev {
+	u32 version;
+	u32 devtype;
+	u32 devnum;
+	u32 mode;
+	u32 sdupdate;
+	u32 reserved[6];
+	u32 hash;
+} __packed;
+
+struct tag_ddr_mem {
+	u32 count;
+	u32 version;
+	u64 bank[20];
+	u32 flags;
+	u32 data[2];
+	u32 hash;
+} __packed;
+
+struct tag_tos_mem {
+	u32 version;
+	struct {
+		char name[8];
+		u64 phy_addr;
+		u32 size;
+		u32 flags;
+	} tee_mem;
+
+	struct {
+		char name[8];
+		u64 phy_addr;
+		u32 size;
+		u32 flags;
+	} drm_mem;
+
+	u64 reserved[7];
+	u32 reserved1;
+	u32 hash;
+} __packed;
+
+struct tag_atf_mem {
+	u32 version;
+	u64 phy_addr;
+	u32 size;
+	u32 flags;
+	u32 reserved[2];
+	u32 hash;
+} __packed;
+
+struct tag_pub_key {
+	u32 version;
+	u32 len;
+	u8  data[768];	/* u32 rsa_n[64], rsa_e[64], rsa_c[64] */
+	u32 flag;
+	u32 reserved[5];
+	u32 hash;
+} __packed;
+
+struct tag_ram_partition {
+	u32 version;
+	u32 count;
+	u32 reserved[4];
+
+	struct {
+		char name[16];
+		u64 start;
+		u64 size;
+	} part[6];
+
+	u32 reserved1[3];
+	u32 hash;
+} __packed;
+
+struct tag_soc_info {
+	u32 version;
+	u32 name;	/* Hex: 0x3288, 0x3399... */
+	u32 flags;
+	u32 reserved[6];
+	u32 hash;
+} __packed;
+
+struct tag_boot1p {
+	u32 version;
+	u32 param[8];
+	u32 reserved[4];
+	u32 hash;
+} __packed;
+
+struct tag_pstore {
+	u32 version;
+	struct {
+		u32 addr;
+		u32 size;
+	} buf[16];
+	u32 hash;
+} __packed;
+
+struct tag_fwver {
+	u32 version;
+	char ver[8][FWVER_LEN];
+	u32 hash;
+} __packed;
+
+struct tag_core {
+	u32 flags;
+	u32 pagesize;
+	u32 rootdev;
+} __packed;
+
+struct tag_header {
+	u32 size;	/* bytes = size * 4 */
+	u32 magic;
+} __packed;
+
+/* Must be 4 bytes align */
+struct tag {
+	struct tag_header hdr;
+	union {
+		struct tag_core		core;
+		struct tag_serial	serial;
+		struct tag_bootdev	bootdev;
+		struct tag_ddr_mem	ddr_mem;
+		struct tag_tos_mem	tos_mem;
+		struct tag_ram_partition ram_part;
+		struct tag_atf_mem	atf_mem;
+		struct tag_pub_key	pub_key;
+		struct tag_soc_info	soc;
+		struct tag_boot1p	boot1p;
+		struct tag_pstore	pstore;
+		struct tag_fwver	fwver;
+	} u;
+} __aligned(4);
+
+#define tag_next(t)	((struct tag *)((u32 *)(t) + (t)->hdr.size))
+#define tag_size(type)	((sizeof(struct tag_header) + sizeof(struct type)) >> 2)
+#define for_each_tag(t, base)		\
+	for (t = base; t->hdr.size; t = tag_next(t))
+
+/*
+ * atags_get_tag - get tag by tag magic
+ *
+ * @magic: tag magic, i.e. ATAG_SERIAL, ATAG_BOOTDEV, ...
+ *
+ * return: NULL on failed, otherwise return the tag that we want.
+ */
+struct tag *atags_get_tag(u32 magic);
+
+/*
+ * atags_is_available - check if atags is available, used for second or
+ *			later pre-loaders.
+ *
+ * return: 0 is not available, otherwise available.
+ */
+int atags_is_available(void);
+
+/*
+ * atags_overflow - check if atags is overflow
+ *
+ * return: 0 if not overflow, otherwise overflow.
+ */
+int atags_overflow(struct tag *t);
+
+/*
+ * atags_bad_magic - check if atags magic is invalid.
+ *
+ * return: 1 if invalid, otherwise valid.
+ */
+int atags_bad_magic(u32 magic);
+#endif
diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
index 1dc92066bb..4165cbe99f 100644
--- a/arch/arm/mach-rockchip/Makefile
+++ b/arch/arm/mach-rockchip/Makefile
@@ -28,6 +28,7 @@  endif
 
 ifeq ($(CONFIG_TPL_BUILD),)
 obj-$(CONFIG_DISPLAY_CPUINFO) += cpu-info.o
+obj-$(CONFIG_ROCKCHIP_RK3588) += atags.o
 endif
 
 obj-$(CONFIG_$(SPL_TPL_)RAM) += sdram.o
diff --git a/arch/arm/mach-rockchip/atags.c b/arch/arm/mach-rockchip/atags.c
new file mode 100644
index 0000000000..9daa2f2fc0
--- /dev/null
+++ b/arch/arm/mach-rockchip/atags.c
@@ -0,0 +1,99 @@ 
+// SPDX-License-Identifier:     GPL-2.0+
+/*
+ * (C) Copyright 2018 Rockchip Electronics Co., Ltd.
+ *
+ */
+
+#include <config.h>
+#include <asm/io.h>
+#include <asm/arch-rockchip/atags.h>
+
+#define HASH_LEN	sizeof(u32)
+
+static u32 js_hash(void *buf, u32 len)
+{
+	u32 i, hash = 0x47C6A7E6;
+	char *data = buf;
+
+	if (!buf || !len)
+		return hash;
+
+	for (i = 0; i < len; i++)
+		hash ^= ((hash << 5) + data[i] + (hash >> 2));
+
+	return hash;
+}
+
+int atags_bad_magic(u32 magic)
+{
+	bool bad;
+
+	bad = ((magic != ATAG_CORE) &&
+	       (magic != ATAG_NONE) &&
+	       (magic < ATAG_SERIAL || magic > ATAG_MAX));
+	if (bad)
+		printf("Magic(%x) is not support\n", magic);
+
+	return bad;
+}
+
+static int atags_size_overflow(struct tag *t, u32 tag_size)
+{
+	return (unsigned long)t + (tag_size << 2) - ATAGS_PHYS_BASE > ATAGS_SIZE;
+}
+
+int atags_overflow(struct tag *t)
+{
+	bool overflow;
+
+	overflow = atags_size_overflow(t, 0) ||
+		   atags_size_overflow(t, t->hdr.size);
+	if (overflow)
+		printf("Tag is overflow\n");
+
+	return overflow;
+}
+
+int atags_is_available(void)
+{
+	struct tag *t = (struct tag *)ATAGS_PHYS_BASE;
+
+	return (t->hdr.magic == ATAG_CORE);
+}
+
+struct tag *atags_get_tag(u32 magic)
+{
+	u32 *hash, calc_hash, size;
+	struct tag *t;
+
+	if (!atags_is_available())
+		return NULL;
+
+	for_each_tag(t, (struct tag *)ATAGS_PHYS_BASE) {
+		if (atags_overflow(t))
+			return NULL;
+
+		if (atags_bad_magic(t->hdr.magic))
+			return NULL;
+
+		if (t->hdr.magic != magic)
+			continue;
+
+		size = t->hdr.size;
+		hash = (u32 *)((ulong)t + (size << 2) - HASH_LEN);
+		if (!*hash) {
+			debug("No hash, magic(%x)\n", magic);
+			return t;
+		}
+		calc_hash = js_hash(t, (size << 2) - HASH_LEN);
+		if (calc_hash == *hash) {
+			debug("Hash okay, magic(%x)\n", magic);
+			return t;
+		}
+		debug("Hash bad, magic(%x), orgHash=%x, nowHash=%x\n",
+		      magic, *hash, calc_hash);
+		return NULL;
+	}
+
+	return NULL;
+}