diff mbox series

[23/31] nds32: Device tree support

Message ID b8120c11ba60eb2a3c7741197c6b2cbf1490bc96.1510118606.git.green.hu@gmail.com
State Not Applicable, archived
Delegated to: David Miller
Headers show
Series Andes(nds32) Linux Kernel Port | expand

Commit Message

Greentime Hu Nov. 8, 2017, 5:55 a.m. UTC 
From: Greentime Hu <greentime@andestech.com>

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
---
 arch/nds32/boot/dts/Makefile   |    8 ++++++
 arch/nds32/boot/dts/ae3xx.dts  |   55 ++++++++++++++++++++++++++++++++++++
 arch/nds32/boot/dts/ag101p.dts |   60 ++++++++++++++++++++++++++++++++++++++++
 arch/nds32/kernel/devtree.c    |   45 ++++++++++++++++++++++++++++++
 4 files changed, 168 insertions(+)
 create mode 100644 arch/nds32/boot/dts/Makefile
 create mode 100644 arch/nds32/boot/dts/ae3xx.dts
 create mode 100644 arch/nds32/boot/dts/ag101p.dts
 create mode 100644 arch/nds32/kernel/devtree.c

Comments

Arnd Bergmann Nov. 8, 2017, 9:53 a.m. UTC | #1 
On Wed, Nov 8, 2017 at 6:55 AM, Greentime Hu <green.hu@gmail.com> wrote:
> From: Greentime Hu <greentime@andestech.com>
>
> Signed-off-by: Vincent Chen <vincentc@andestech.com>
> Signed-off-by: Greentime Hu <greentime@andestech.com>
> ---
>  arch/nds32/boot/dts/Makefile   |    8 ++++++
>  arch/nds32/boot/dts/ae3xx.dts  |   55 ++++++++++++++++++++++++++++++++++++
>  arch/nds32/boot/dts/ag101p.dts |   60 ++++++++++++++++++++++++++++++++++++++++
>  arch/nds32/kernel/devtree.c    |   45 ++++++++++++++++++++++++++++++
>  4 files changed, 168 insertions(+)
>  create mode 100644 arch/nds32/boot/dts/Makefile
>  create mode 100644 arch/nds32/boot/dts/ae3xx.dts
>  create mode 100644 arch/nds32/boot/dts/ag101p.dts
>  create mode 100644 arch/nds32/kernel/devtree.c
>
> diff --git a/arch/nds32/boot/dts/Makefile b/arch/nds32/boot/dts/Makefile
> new file mode 100644
> index 0000000..d31faa8
> --- /dev/null
> +++ b/arch/nds32/boot/dts/Makefile
> @@ -0,0 +1,8 @@
> +ifneq '$(CONFIG_NDS32_BUILTIN_DTB)' '""'
> +BUILTIN_DTB := $(patsubst "%",%,$(CONFIG_NDS32_BUILTIN_DTB)).dtb.o
> +else
> +BUILTIN_DTB :=
> +endif
> +obj-$(CONFIG_OF) += $(BUILTIN_DTB)

For new architectures, I think it's better to not support built-in dtb
but instead require the
boot loader to be aware of device trees.

> +clean-files := *.dtb *.dtb.S
> diff --git a/arch/nds32/boot/dts/ae3xx.dts b/arch/nds32/boot/dts/ae3xx.dts
> new file mode 100644
> index 0000000..b6c85dc
> --- /dev/null
> +++ b/arch/nds32/boot/dts/ae3xx.dts
> @@ -0,0 +1,55 @@
> +/dts-v1/;
> +/ {
> +       compatible = "nds32 ae3xx";

ae3xx looks like a wildcard name for multiple boards. Please always
have compatible
names without wildcards. You usually also want to list both the SoC
and the board
here.

> +       #address-cells = <1>;
> +       #size-cells = <1>;
> +       interrupt-parent = <&intc>;
> +
> +       chosen {
> +               bootargs = "console=ttyS0,38400n8 earlyprintk=uart8250-32bit,0xf0300000 debug loglevel=7";
> +       };

Remove the earlyprintk option from the bootargs here, regular boards
should never rely
on earlyprintk. The "earlycon" support in the uart drivers works
almost as well (it starts
slightly later in the boot process), and it will pick up the uart from
the chosen/stdout-path
property.

> +       if (!params || !early_init_dt_scan(params)) {
> +               pr_crit("\n"
> +                       "Error: invalid device tree blob at (virtual address 0x%p)\n"
> +                       "The dtb must be 8-byte aligned and must not exceed 8 KB in size\n"
> +                       "\nPlease check your bootloader.", params);

What is the 8KB limit for the dtb for? This sounds really limiting
once you get to
more complex SoCs.

       Arnd
Greentime Hu Nov. 9, 2017, 7:48 a.m. UTC | #2 
2017-11-08 17:53 GMT+08:00 Arnd Bergmann <arnd@arndb.de>:
> On Wed, Nov 8, 2017 at 6:55 AM, Greentime Hu <green.hu@gmail.com> wrote:
>> From: Greentime Hu <greentime@andestech.com>
>>
>> Signed-off-by: Vincent Chen <vincentc@andestech.com>
>> Signed-off-by: Greentime Hu <greentime@andestech.com>
>> ---
>>  arch/nds32/boot/dts/Makefile   |    8 ++++++
>>  arch/nds32/boot/dts/ae3xx.dts  |   55 ++++++++++++++++++++++++++++++++++++
>>  arch/nds32/boot/dts/ag101p.dts |   60 ++++++++++++++++++++++++++++++++++++++++
>>  arch/nds32/kernel/devtree.c    |   45 ++++++++++++++++++++++++++++++
>>  4 files changed, 168 insertions(+)
>>  create mode 100644 arch/nds32/boot/dts/Makefile
>>  create mode 100644 arch/nds32/boot/dts/ae3xx.dts
>>  create mode 100644 arch/nds32/boot/dts/ag101p.dts
>>  create mode 100644 arch/nds32/kernel/devtree.c
>>
>> diff --git a/arch/nds32/boot/dts/Makefile b/arch/nds32/boot/dts/Makefile
>> new file mode 100644
>> index 0000000..d31faa8
>> --- /dev/null
>> +++ b/arch/nds32/boot/dts/Makefile
>> @@ -0,0 +1,8 @@
>> +ifneq '$(CONFIG_NDS32_BUILTIN_DTB)' '""'
>> +BUILTIN_DTB := $(patsubst "%",%,$(CONFIG_NDS32_BUILTIN_DTB)).dtb.o
>> +else
>> +BUILTIN_DTB :=
>> +endif
>> +obj-$(CONFIG_OF) += $(BUILTIN_DTB)
>
> For new architectures, I think it's better to not support built-in dtb
> but instead require the
> boot loader to be aware of device trees.

Thanks.
I got your point and we have uboot supporting DTB too.
But we use gdb to load vmlinux without uboot sometimes, it can help us
to verify kernel more easily.
If dtb pointer is set by uboot, we will use it instead of using built-in dtb.

>> +clean-files := *.dtb *.dtb.S
>> diff --git a/arch/nds32/boot/dts/ae3xx.dts b/arch/nds32/boot/dts/ae3xx.dts
>> new file mode 100644
>> index 0000000..b6c85dc
>> --- /dev/null
>> +++ b/arch/nds32/boot/dts/ae3xx.dts
>> @@ -0,0 +1,55 @@
>> +/dts-v1/;
>> +/ {
>> +       compatible = "nds32 ae3xx";
>
> ae3xx looks like a wildcard name for multiple boards. Please always
> have compatible
> names without wildcards. You usually also want to list both the SoC
> and the board
> here.

Thanks.
It looks a little bit weird but its not a wildcards. :p
I will list all the names instead of wildcards if I need to add more platforms.

>> +       #address-cells = <1>;
>> +       #size-cells = <1>;
>> +       interrupt-parent = <&intc>;
>> +
>> +       chosen {
>> +               bootargs = "console=ttyS0,38400n8 earlyprintk=uart8250-32bit,0xf0300000 debug loglevel=7";
>> +       };
>
> Remove the earlyprintk option from the bootargs here, regular boards
> should never rely
> on earlyprintk. The "earlycon" support in the uart drivers works
> almost as well (it starts
> slightly later in the boot process), and it will pick up the uart from
> the chosen/stdout-path
> property.

Thanks.
I will remove it.

>> +       if (!params || !early_init_dt_scan(params)) {
>> +               pr_crit("\n"
>> +                       "Error: invalid device tree blob at (virtual address 0x%p)\n"
>> +                       "The dtb must be 8-byte aligned and must not exceed 8 KB in size\n"
>> +                       "\nPlease check your bootloader.", params);
>
> What is the 8KB limit for the dtb for? This sounds really limiting
> once you get to
> more complex SoCs.

Thanks.
We allow uboot to set its start address and we think it might not be
too big thus we limit it to 8KB.
Maybe I should use a big size for complex SoCs.
I will update it in the next version patch.
diff mbox series

Patch

diff --git a/arch/nds32/boot/dts/Makefile b/arch/nds32/boot/dts/Makefile
new file mode 100644
index 0000000..d31faa8
--- /dev/null
+++ b/arch/nds32/boot/dts/Makefile
@@ -0,0 +1,8 @@ 
+ifneq '$(CONFIG_NDS32_BUILTIN_DTB)' '""'
+BUILTIN_DTB := $(patsubst "%",%,$(CONFIG_NDS32_BUILTIN_DTB)).dtb.o
+else
+BUILTIN_DTB :=
+endif
+obj-$(CONFIG_OF) += $(BUILTIN_DTB)
+
+clean-files := *.dtb *.dtb.S
diff --git a/arch/nds32/boot/dts/ae3xx.dts b/arch/nds32/boot/dts/ae3xx.dts
new file mode 100644
index 0000000..b6c85dc
--- /dev/null
+++ b/arch/nds32/boot/dts/ae3xx.dts
@@ -0,0 +1,55 @@ 
+/dts-v1/;
+/ {
+	compatible = "nds32 ae3xx";
+	#address-cells = <1>;
+	#size-cells = <1>;
+	interrupt-parent = <&intc>;
+
+	chosen {
+		bootargs = "console=ttyS0,38400n8 earlyprintk=uart8250-32bit,0xf0300000 debug loglevel=7";
+	};
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x00000000 0x40000000>;
+	};
+
+	cpus {
+		cpu@0 {
+			device_type = "cpu";
+			compatible = "andestech,n13", "andestech,n15";
+		};
+	};
+
+	intc: interrupt-controller {
+		compatible = "andestech,ativic32";
+		#interrupt-cells = <2>;
+		interrupt-controller;
+	};
+
+	serial0: serial@f0300000 {
+		compatible = "andestech,uart16550", "ns16550a";
+		reg = <0xf0300000 0x1000>;
+		interrupts = <8 4>;
+		clock-frequency = <14745600>;
+		reg-shift = <2>;
+		reg-offset = <32>;
+		no-loopback-test = <1>;
+	};
+
+	timer0: timer@f0400000 {
+		compatible = "andestech,atcpit100";
+		reg = <0xf0400000 0x1000>;
+		interrupts = <2 4>;
+		clock-frequency = <30000000>;
+		cycle-count-offset = <0x38>;
+		cycle-count-down;
+	};
+
+	mac0: mac@e0100000 {
+		compatible = "andestech,atmac100";
+		reg = <0xe0100000 0x1000>;
+		interrupts = <18 4>;
+	};
+
+};
diff --git a/arch/nds32/boot/dts/ag101p.dts b/arch/nds32/boot/dts/ag101p.dts
new file mode 100644
index 0000000..b34760b
--- /dev/null
+++ b/arch/nds32/boot/dts/ag101p.dts
@@ -0,0 +1,60 @@ 
+/dts-v1/;
+/ {
+	compatible = "nds32 ag101p";
+	#address-cells = <1>;
+	#size-cells = <1>;
+	interrupt-parent = <&intc>;
+
+	chosen {
+		bootargs = "console=ttyS0,38400n8 earlyprintk=uart8250-32bit,0x99600000 debug loglevel=7";
+	};
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x00000000 0x40000000>;
+	};
+
+	cpus {
+		cpu@0 {
+			device_type = "cpu";
+			compatible = "andestech,n13";
+			next-level-cache = <&L2>;
+		};
+	};
+
+	intc: interrupt-controller {
+		compatible = "andestech,atnointc010";
+		#interrupt-cells = <2>;
+		interrupt-controller;
+	};
+
+	serial0: serial@99600000 {
+		compatible = "andestech,uart16550", "ns16550a";
+		reg = <0x99600000 0x1000>;
+		interrupts = <7 4>;
+		clock-frequency = <14745600>;
+		reg-shift = <2>;
+		no-loopback-test = <1>;
+	};
+
+	timer0: timer@98400000 {
+		compatible = "andestech,atftmr010";
+		reg = <0x98400000 0x1000>;
+		interrupts = <19 4>;
+		clock-frequency = <15000000>;
+		cycle-count-offset = <0x20>;
+	};
+
+	mac0: mac@90900000 {
+		compatible = "andestech,atmac100";
+		reg = <0x90900000 0x1000>;
+		interrupts = <25 4>;
+	};
+
+	L2: l2-cache {
+		compatible = "andestech,atl2c";
+		reg = <0x90f00000 0x1000>;
+		cache-unified;
+		cache-level = <2>;
+	};
+};
diff --git a/arch/nds32/kernel/devtree.c b/arch/nds32/kernel/devtree.c
new file mode 100644
index 0000000..2af0f1c
--- /dev/null
+++ b/arch/nds32/kernel/devtree.c
@@ -0,0 +1,45 @@ 
+/*
+ * Copyright (C) 2005-2017 Andes Technology Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/memblock.h>
+#include <linux/of_fdt.h>
+#include <linux/bootmem.h>
+
+void __init early_init_dt_add_memory_arch(u64 base, u64 size)
+{
+	size &= PAGE_MASK;
+	memblock_add_node(base, size, 0);
+}
+
+void *__init early_init_dt_alloc_memory_arch(u64 size, u64 align)
+{
+	return alloc_bootmem_align(size, align);
+}
+
+void __init early_init_devtree(void *params)
+{
+	if (!params || !early_init_dt_scan(params)) {
+		pr_crit("\n"
+			"Error: invalid device tree blob at (virtual address 0x%p)\n"
+			"The dtb must be 8-byte aligned and must not exceed 8 KB in size\n"
+			"\nPlease check your bootloader.", params);
+
+		while (true)
+			cpu_relax();
+	}
+
+	dump_stack_set_arch_desc("%s (DT)", of_flat_dt_get_machine_name());
+}