[U-Boot,V4,2/2] MTD/SPI: add support for Ramtron FRAMs

Submitted by Reinhard Meyer on Sept. 14, 2010, 2:50 p.m.

Details

Message ID 1284475809-12509-3-git-send-email-u-boot@emk-elektronik.de
State Superseded
Delegated to: Mike Frysinger
Headers show

Commit Message

Reinhard Meyer Sept. 14, 2010, 2:50 p.m.
JEDEC types
non JEDEC types

Signed-off-by: Reinhard Meyer <u-boot@emk-elektronik.de>
---
 drivers/mtd/spi/Makefile             |    1 +
 drivers/mtd/spi/ramtron.c            |  321 ++++++++++++++++++++++++++++++++++
 drivers/mtd/spi/spi_flash.c          |    8 +
 drivers/mtd/spi/spi_flash_internal.h |    1 +
 4 files changed, 331 insertions(+), 0 deletions(-)
 create mode 100644 drivers/mtd/spi/ramtron.c

Comments

Mike Frysinger Sept. 14, 2010, 3:01 p.m.
On Tuesday, September 14, 2010 10:50:09 Reinhard Meyer wrote:
> JEDEC types
> non JEDEC types

this changelog is useless ... either make it say something, or just leave it 
empty

> +static int ramtron_common(struct spi_flash *flash,
> +		u32 offset, size_t len, void *buf, u8 command)
> +{
> +
> +	if (sn->params->addr_len == 3 && sn->params->merge_cmd == 0) {
> +		cmd[0] = command;
> +		cmd[1] = offset >> 16;
> +		cmd[2] = offset >> 8;
> +		cmd[3] = offset;
> +		cmd_len = 4;
> +	}
> +	else if (sn->params->addr_len == 2 && sn->params->merge_cmd == 0) {
> +		cmd[0] = command;
> +		cmd[1] = offset >> 8;
> +		cmd[2] = offset;
> +		cmd_len = 3;
> +	}
> +	else {

i thought i had mentioned this before, but those else statements need cuddling

> +	/* claim the bus */
> +	ret = spi_claim_bus(flash->spi);
> +	if (ret) {
> +		debug("SF: Unable to claim SPI bus\n");
> +		return ret;
> +	}

i'm thinking we should push the bus claim from the read/write funcs into the 
common spi flash layer ... not that this is specific to your flash.  we can do 
this after yours gets merged.

> +	sn = malloc(sizeof(struct ramtron_spi_fram));

sizeof(*sn)

otherwise, this looks good
-mike
Reinhard Meyer (-VC) Oct. 4, 2010, 6:31 a.m.
Dear Mike Frysinger, All:)
> On Tuesday, September 14, 2010 10:50:09 Reinhard Meyer wrote:
>> JEDEC types
>> non JEDEC types
> 
> this changelog is useless ... either make it say something, or just leave it 
> empty
> 
>> +static int ramtron_common(struct spi_flash *flash,
>> +		u32 offset, size_t len, void *buf, u8 command)
>> +{
>> +
>> +	if (sn->params->addr_len == 3 && sn->params->merge_cmd == 0) {
>> +		cmd[0] = command;
>> +		cmd[1] = offset >> 16;
>> +		cmd[2] = offset >> 8;
>> +		cmd[3] = offset;
>> +		cmd_len = 4;
>> +	}
>> +	else if (sn->params->addr_len == 2 && sn->params->merge_cmd == 0) {
>> +		cmd[0] = command;
>> +		cmd[1] = offset >> 8;
>> +		cmd[2] = offset;
>> +		cmd_len = 3;
>> +	}
>> +	else {
> 
> i thought i had mentioned this before, but those else statements need cuddling
> 
>> +	/* claim the bus */
>> +	ret = spi_claim_bus(flash->spi);
>> +	if (ret) {
>> +		debug("SF: Unable to claim SPI bus\n");
>> +		return ret;
>> +	}
> 
> i'm thinking we should push the bus claim from the read/write funcs into the 
> common spi flash layer ... not that this is specific to your flash.  we can do 
> this after yours gets merged.
> 
>> +	sn = malloc(sizeof(struct ramtron_spi_fram));
> 
> sizeof(*sn)
> 
> otherwise, this looks good
> -mike

I am unsure whether currently I should put further effort into this, because this
won't work on architectures with incomplete relocation. The pointers in the
"probe" table would need relocation fixups otherwise.

Reinhard
Wolfgang Denk Oct. 4, 2010, 7:17 a.m.
Dear Reinhard Meyer,

In message <4CA974B5.8030905@emk-elektronik.de> you wrote:
>
> I am unsure whether currently I should put further effort into this, because this
> won't work on architectures with incomplete relocation. The pointers in the
> "probe" table would need relocation fixups otherwise.

The relocation problems will be fixed one way or another. We must find
a solution for this problem, so please go on...

Best regards,

Wolfgang Denk

Patch hide | download patch | download mbox

diff --git a/drivers/mtd/spi/Makefile b/drivers/mtd/spi/Makefile
index 4f11b36..a082ca7 100644
--- a/drivers/mtd/spi/Makefile
+++ b/drivers/mtd/spi/Makefile
@@ -32,6 +32,7 @@  COBJS-$(CONFIG_SPI_FLASH_SPANSION)	+= spansion.o
 COBJS-$(CONFIG_SPI_FLASH_SST)	+= sst.o
 COBJS-$(CONFIG_SPI_FLASH_STMICRO)	+= stmicro.o
 COBJS-$(CONFIG_SPI_FLASH_WINBOND)	+= winbond.o
+COBJS-$(CONFIG_SPI_FRAM_RAMTRON)	+= ramtron.o
 COBJS-$(CONFIG_SPI_M95XXX) += eeprom_m95xxx.o
 
 COBJS	:= $(COBJS-y)
diff --git a/drivers/mtd/spi/ramtron.c b/drivers/mtd/spi/ramtron.c
new file mode 100644
index 0000000..dc4e6a0
--- /dev/null
+++ b/drivers/mtd/spi/ramtron.c
@@ -0,0 +1,321 @@ 
+/*
+ * (C) Copyright 2010
+ * Reinhard Meyer, EMK Elektronik, reinhard.meyer@emk-elektronik.de
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/*
+ * Note: RAMTRON SPI FRAMs are ferroelectric, nonvolatile RAMs
+ * with an interface identical to SPI flash devices.
+ * However since they behave like RAM there are no delays or
+ * busy polls required. They can sustain read or write at the
+ * allowed SPI bus speed, which can be 40 MHz for some devices.
+ *
+ * Unfortunately some RAMTRON devices do not have a means of
+ * identifying them. They will leave the SO line undriven when
+ * the READ-ID command is issued. It is therefore mandatory
+ * that the MISO line has a proper pull-up, so that READ-ID
+ * will return a row of 0xff. This 0xff pseudo-id will cause
+ * probes by all vendor specific functions that are designed
+ * to handle it. If the MISO line is not pulled up, READ-ID
+ * could return any random noise, even mimicking another
+ * device.
+ *
+ * We use CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
+ * to define which device will be assumed after a simple status
+ * register verify. This method is prone to false positive
+ * detection and should therefore be the last to be tried.
+ * Enter it in the last position in the table in spi_flash.c!
+ *
+ * The define CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC both activates
+ * compilation of the special handler and defines the device
+ * to assume.
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <spi_flash.h>
+#include "spi_flash_internal.h"
+
+/* RAMTRON commands common to all devices */
+#define CMD_RAMTRON_WREN	0x06	/* Write Enable */
+#define CMD_RAMTRON_WRDI	0x04	/* Write Disable */
+#define CMD_RAMTRON_RDSR	0x05	/* Read Status Register */
+#define CMD_RAMTRON_WRSR	0x01	/* Write Status Register */
+#define CMD_RAMTRON_READ	0x03	/* Read Data Bytes */
+#define CMD_RAMTRON_WRITE	0x02	/* Write Data Bytes */
+/* not all have those: */
+#define CMD_RAMTRON_FSTRD	0x0b	/* Fast Read (for compatibility - not used here) */
+#define CMD_RAMTRON_SLEEP	0xb9	/* Enter Sleep Mode */
+#define CMD_RAMTRON_RDID	0x9f	/* Read ID */
+#define CMD_RAMTRON_SNR		0xc3	/* Read Serial Number */
+
+/*
+ * Properties of supported FRAMs
+ * Note: speed is currently not used because we have no method to deliver that
+ * value to the upper layers
+ */
+struct ramtron_spi_fram_params {
+	u32	size;		/* size in bytes */
+	u8	addr_len;	/* number of address bytes */
+	u8	merge_cmd;	/* some address bits are in the command byte */
+	u8	id1;		/* device ID 1 (family, density) */
+	u8	id2;		/* device ID 2 (sub, rev, rsvd) */
+	u32	speed;		/* max. SPI clock in Hz */
+	const char *name;	/* name for display and/or matching */
+};
+
+struct ramtron_spi_fram {
+	struct spi_flash flash;
+	const struct ramtron_spi_fram_params *params;
+};
+
+static inline struct ramtron_spi_fram *to_ramtron_spi_fram(struct spi_flash
+							     *flash)
+{
+	return container_of(flash, struct ramtron_spi_fram, flash);
+}
+
+/*
+ * table describing supported FRAM chips:
+ * chips without RDID command must have the values 0xff for id1 and id2
+ */
+static const struct ramtron_spi_fram_params ramtron_spi_fram_table[] = {
+	{
+		.size = 32*1024,
+		.addr_len = 2,
+		.merge_cmd = 0,
+		.id1 = 0x22,
+		.id2 = 0x00,
+		.speed = 40000000,
+		.name = "FM25V02",
+	},
+	{
+		.size = 32*1024,
+		.addr_len = 2,
+		.merge_cmd = 0,
+		.id1 = 0x22,
+		.id2 = 0x01,
+		.speed = 40000000,
+		.name = "FM25VN02",
+	},
+	{
+		.size = 64*1024,
+		.addr_len = 2,
+		.merge_cmd = 0,
+		.id1 = 0x23,
+		.id2 = 0x00,
+		.speed = 40000000,
+		.name = "FM25V05",
+	},
+	{
+		.size = 64*1024,
+		.addr_len = 2,
+		.merge_cmd = 0,
+		.id1 = 0x23,
+		.id2 = 0x01,
+		.speed = 40000000,
+		.name = "FM25VN05",
+	},
+	{
+		.size = 128*1024,
+		.addr_len = 3,
+		.merge_cmd = 0,
+		.id1 = 0x24,
+		.id2 = 0x00,
+		.speed = 40000000,
+		.name = "FM25V10",
+	},
+	{
+		.size = 128*1024,
+		.addr_len = 3,
+		.merge_cmd = 0,
+		.id1 = 0x24,
+		.id2 = 0x01,
+		.speed = 40000000,
+		.name = "FM25VN10",
+	},
+#ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
+	{
+		.size = 256*1024,
+		.addr_len = 3,
+		.merge_cmd = 0,
+		.id1 = 0xff,
+		.id2 = 0xff,
+		.speed = 40000000,
+		.name = "FM25H20",
+	},
+#endif
+};
+
+static int ramtron_common(struct spi_flash *flash,
+		u32 offset, size_t len, void *buf, u8 command)
+{
+	struct ramtron_spi_fram *sn = to_ramtron_spi_fram(flash);
+	u8 cmd[4];
+	int cmd_len;
+	int ret;
+
+	if (sn->params->addr_len == 3 && sn->params->merge_cmd == 0) {
+		cmd[0] = command;
+		cmd[1] = offset >> 16;
+		cmd[2] = offset >> 8;
+		cmd[3] = offset;
+		cmd_len = 4;
+	}
+	else if (sn->params->addr_len == 2 && sn->params->merge_cmd == 0) {
+		cmd[0] = command;
+		cmd[1] = offset >> 8;
+		cmd[2] = offset;
+		cmd_len = 3;
+	}
+	else {
+		printf("SF: unsupported addr_len or merge_cmd\n");
+		return -1;
+	}
+
+	/* claim the bus */
+	ret = spi_claim_bus(flash->spi);
+	if (ret) {
+		debug("SF: Unable to claim SPI bus\n");
+		return ret;
+	}
+
+	if (command == CMD_RAMTRON_WRITE) {
+		/* send WREN */
+		ret = spi_flash_cmd(flash->spi, CMD_RAMTRON_WREN, NULL, 0);
+		if (ret < 0) {
+			debug("SF: Enabling Write failed\n");
+			goto releasebus;
+		}
+	}
+
+	/* do the transaction */
+	if (command == CMD_RAMTRON_WRITE)
+		ret = spi_flash_cmd_write(flash->spi, cmd, cmd_len, buf, len);
+	else
+		ret = spi_flash_cmd_read(flash->spi, cmd, cmd_len, buf, len);
+	if (ret < 0)
+		debug("SF: Transaction failed\n");
+
+releasebus:
+	/* release the bus */
+	spi_release_bus(flash->spi);
+	return ret;
+}
+
+static int ramtron_read(struct spi_flash *flash,
+		u32 offset, size_t len, void *buf)
+{
+	return ramtron_common(flash, offset, len, buf,
+		CMD_RAMTRON_READ);
+}
+
+static int ramtron_write(struct spi_flash *flash,
+		u32 offset, size_t len, const void *buf)
+{
+	return ramtron_common(flash, offset, len, (void *)buf,
+		CMD_RAMTRON_WRITE);
+}
+
+int ramtron_erase(struct spi_flash *flash, u32 offset, size_t len)
+{
+	debug("SF: Erase of RAMTRON FRAMs is pointless\n");
+	return -1;
+}
+
+/*
+ * nore: we are called here with idcode pointing to the first non-0x7f byte
+ * already!
+ */
+struct spi_flash *spi_fram_probe_ramtron(struct spi_slave *spi, u8 *idcode)
+{
+	const struct ramtron_spi_fram_params *params;
+	struct ramtron_spi_fram *sn;
+	unsigned int i;
+#ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
+	int ret;
+	u8 sr;
+#endif
+
+	/* NOTE: the bus has been claimed before this function is called! */
+	switch (idcode[0]) {
+	case 0xc2:
+		/* JEDEC conformant RAMTRON id */
+		for (i = 0; i < ARRAY_SIZE(ramtron_spi_fram_table); i++) {
+			params = &ramtron_spi_fram_table[i];
+			if (idcode[1] == params->id1 && idcode[2] == params->id2)
+				goto found;
+		}
+		break;
+#ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
+	case 0xff:
+		/*
+		 * probably open MISO line, pulled up.
+		 * We COULD have a non JEDEC conformant FRAM here,
+		 * read the status register to verify
+		 */
+		ret = spi_flash_cmd(spi, CMD_RAMTRON_RDSR, &sr, 1);
+		if (ret)
+			return NULL;
+
+		/* Bits 5,4,0 are fixed 0 for all devices */
+		if ((sr & 0x31) != 0x00)
+			return NULL;
+		/* now find the device */
+		for (i = 0; i < ARRAY_SIZE(ramtron_spi_fram_table); i++) {
+			params = &ramtron_spi_fram_table[i];
+			if (!strcmp(params->name, CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC))
+				goto found;
+		}
+		debug("SF: Unsupported non-JEDEC RAMTRON device "
+			CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC "\n");
+		break;
+#endif
+	default:
+		break;
+	}
+
+	/* arriving here means no method has found a device we can handle */
+	debug("SF/ramtron: unsupported device id0=%02x id1=%02x id2=%02x\n",
+		idcode[0], idcode[1], idcode[2]);
+	return NULL;
+
+found:
+	sn = malloc(sizeof(struct ramtron_spi_fram));
+	if (!sn) {
+		debug("SF: Failed to allocate memory\n");
+		return NULL;
+	}
+
+	sn->params = params;
+	sn->flash.spi = spi;
+	sn->flash.name = params->name;
+
+	sn->flash.write = ramtron_write;
+	sn->flash.read = ramtron_read;
+	sn->flash.erase = ramtron_erase;
+	sn->flash.size = params->size;
+
+	printf("SF: Detected %s with size ", params->name);
+	print_size(sn->flash.size, "\n");
+
+	return &sn->flash;
+}
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index e19f47d..3f8c8e1 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -155,6 +155,14 @@  const struct {
 #ifdef CONFIG_SPI_FLASH_SST
 	{ 0, 0xBF, spi_flash_probe_sst, },
 #endif
+#ifdef CONFIG_SPI_FRAM_RAMTRON
+	{ 6, 0xc2, spi_fram_probe_ramtron, },
+# ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
+	{ 0, 0xff, spi_fram_probe_ramtron, },
+# endif
+# undef IDBUF_LEN
+# define IDBUF_LEN 9 /* we need to read 6+3 bytes */
+#endif
 };
 
 struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs,
diff --git a/drivers/mtd/spi/spi_flash_internal.h b/drivers/mtd/spi/spi_flash_internal.h
index 08546fb..9bc43dd 100644
--- a/drivers/mtd/spi/spi_flash_internal.h
+++ b/drivers/mtd/spi/spi_flash_internal.h
@@ -50,3 +50,4 @@  struct spi_flash *spi_flash_probe_macronix(struct spi_slave *spi, u8 *idcode);
 struct spi_flash *spi_flash_probe_sst(struct spi_slave *spi, u8 *idcode);
 struct spi_flash *spi_flash_probe_stmicro(struct spi_slave *spi, u8 *idcode);
 struct spi_flash *spi_flash_probe_winbond(struct spi_slave *spi, u8 *idcode);
+struct spi_flash *spi_fram_probe_ramtron(struct spi_slave *spi, u8 *idcode);