[U-Boot] [PATCH 1/2 v1] sf: probe: Add support Atmel AT45DB series devices special commands
Peng Fan
Peng.Fan at freescale.com
Thu Mar 26 12:03:14 CET 2015
On 3/26/2015 6:50 PM, Wang Haikun-B53464 wrote:
> On 3/26/2015 11:05 AM, Fan Peng-B51431 wrote:
>> Hi Haikun,
>>
>> On 3/26/2015 10:39 AM, Wang Haikun-B53464 wrote:
>>> On 3/25/2015 10:10 PM, Fan Peng-B51431 wrote:
>>>> Hi Haikun,
>>>>
>>>> On 3/25/2015 8:35 PM, Haikun Wang wrote:
>>>>> From: Haikun Wang <Haikun.Wang at freescale.com>
>>>>>
>>>>> Atmel AT45DB series devices commands is different from common spi flash
>>>>> commands. This patch add support for AT45DB special commands.
>>>>> Add a flag AT45DB_CMD to control whether use those commands.
>>>>>
>>>>> Signed-off-by: Haikun Wang <Haikun.Wang at freescale.com>
>>>>> ---
>>>>>
>>>>> Changes in v1: None
>>>>>
>>>>> drivers/mtd/spi/sf_internal.h | 7 +++++++
>>>>> drivers/mtd/spi/sf_ops.c | 2 +-
>>>>> drivers/mtd/spi/sf_probe.c | 10 ++++++++++
>>>>> 3 files changed, 18 insertions(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/drivers/mtd/spi/sf_internal.h b/drivers/mtd/spi/sf_internal.h
>>>>> index 785f7a9..234af21 100644
>>>>> --- a/drivers/mtd/spi/sf_internal.h
>>>>> +++ b/drivers/mtd/spi/sf_internal.h
>>>>> @@ -43,6 +43,7 @@ enum {
>>>>> SST_BP = 1 << 3,
>>>>> SST_WP = 1 << 4,
>>>>> WR_QPP = 1 << 5,
>>>>> + AT45DB_CMD = 1 << 6,
>>>>> };
>>>>>
>>>>> #define SST_WR (SST_BP | SST_WP)
>>>>> @@ -106,6 +107,12 @@ enum {
>>>>> #define SPI_FLASH_PAGE_ERASE_TIMEOUT (5 * CONFIG_SYS_HZ)
>>>>> #define SPI_FLASH_SECTOR_ERASE_TIMEOUT (10 * CONFIG_SYS_HZ)
>>>>>
>>>>> +/* Atmel AT45DB specific */
>>>>> +#define CMD_ATMEL_PAGE_PROGRAM 0x82
>>>> Why not use 0x2 to align with current mtd/spi framework?
>>> I didn't find the program command '0x2' in AT45DB021D datasheet.
>> My fault. 0x2h is supported by AT45DB021E, but not AT45DB021D. You can
>> use 0x82.
> Does AT45DB021E support '0x82'?
Yeah. 0x82h "Main Memory Page Program through Buffer with Built-In Erase"
>>> Do you ever use it in AT45DBxxxx flash chip?
>> I used a similar chip AT45DB021E, not AT45DB021D. And I have a local
>> patch for this chip.
>>
>>>>> +#define CMD_ATMEL_READ_STATUS 0xd7
>>>>> +#define CMD_ATMEL_FLAG_STATUS 0xd7
>>>>> +#define CMD_ATMEL_BLK_ERASE 0x50
>>>>> +
>>>>> /* SST specific */
>>>>> #ifdef CONFIG_SPI_FLASH_SST
>>>>> # define CMD_SST_BP 0x02 /* Byte Program */
>>>>> diff --git a/drivers/mtd/spi/sf_ops.c b/drivers/mtd/spi/sf_ops.c
>>>>> index 34bc54e..27ce5f9 100644
>>>>> --- a/drivers/mtd/spi/sf_ops.c
>>>>> +++ b/drivers/mtd/spi/sf_ops.c
>>>>> @@ -165,7 +165,7 @@ int spi_flash_cmd_wait_ready(struct spi_flash *flash, unsigned long timeout)
>>>>> u8 poll_bit = STATUS_WIP;
>>>>> u8 cmd = flash->poll_cmd;
>>>>>
>>>>> - if (cmd == CMD_FLAG_STATUS) {
>>>>> + if (cmd == CMD_FLAG_STATUS || cmd == CMD_ATMEL_FLAG_STATUS) {
>>>>> poll_bit = STATUS_PEC;
>>>>> check_status = poll_bit;
>>>>> }
>>>>> diff --git a/drivers/mtd/spi/sf_probe.c b/drivers/mtd/spi/sf_probe.c
>>>>> index 4103723..2ccddf2 100644
>>>>> --- a/drivers/mtd/spi/sf_probe.c
>>>>> +++ b/drivers/mtd/spi/sf_probe.c
>>>>> @@ -226,6 +226,16 @@ static int spi_flash_validate_params(struct spi_slave *spi, u8 *idcode,
>>>>> flash->poll_cmd = CMD_FLAG_STATUS;
>>>>> #endif
>>>>>
>>>>> +#ifdef CONFIG_SPI_FLASH_ATMEL
>>>>> + if (params->flags & AT45DB_CMD) {
>>>>> + flash->poll_cmd = CMD_ATMEL_READ_STATUS;
>>>>> + flash->write_cmd = CMD_ATMEL_PAGE_PROGRAM;
>>>>> + /* use block-erase command, eight pages */
>>>>> + flash->erase_cmd = CMD_ATMEL_BLK_ERASE;
>>>>> + flash->erase_size = flash->page_size * 8;
>>>>> + }
>>>>> +#endif
>>>>> +
>>>> The SPI Flash's default page size is 264 bytes, but mtd/spi framework
>>>> supports 256 and 512 bytes for one page. In your patch, you does not
>>>> handle such case, can your driver works as expected?
>>> Fine, I know mtd/spi framework doesn't support page-size of 264bytes.
>>> In fact we change the chip's page-size to 256bytes before using it.
>> If others use a same chip, he/she has no idea about this.
>>> It is a big work to adjust the framework support 264bytes.
>> No big work, just send a configuration command to the chip.
> I am not true whether others approve this.
> As you said chips only can be configured once and it is irreversible.
> At least we should let user choice configure or not.
Hmm.. then you can add the checking page size stuff there as you like.
>
> Best regards,
> Wang Haikun
>>> So how about add a check here, if the chip has a page-size of 264bytes,
>>> we just return an error.
>> This AT45XXD chip's page size can only be configured once. you can check
>> the status register, BIT 0's meaning is PAGE SIZE is 256 or 264.
>> If the page size is 264, you can configure the chip to 256 seeing "11.1
>> Programming the Configuration Register". If the page size is already
>> 256, no need to configure it again.
>> You can added related function in sf_ops.c and invoke this function in
>> sf_probe.c when probe.
>> you can take the following piece of code as a reference as you like, it
>> works for AT45DB021E. About read status, I suppose you can use the
>> FLAG_STATUS to get the correct value.
>>
>> #if defined(CONFIG_SPI_FLASH_ATMEL)
>> /*
>> * For the AT45DB021E, there are an extra eight bytes
>> * of memory in each page for a total of an extra 8KB
>> * (64-Kbits) of user-accessible memory.
>> * In order to be compatible with spi framework, we use 256bytes.
>> */
>>
>> int spi_flash_cmd_write_config(struct spi_flash *flash, u8 wc)
>> {
>> u8 data[3];
>> u8 cmd;
>> int ret;
>>
>> ret = spi_flash_cmd_read_status(flash, &data[0]);
>> if (ret < 0)
>> return ret;
>>
>> /*
>> * PAGE SIZE Page Size, bit 0.
>> * 0 Device is configured for standard DataFlash page size (264 bytes).
>> * 1 Device is configured for “power of 2” binary page size (256
>> bytes).
>> */
>> if (wc == SPI_FLASH_PAGE_256) {
>> /* Already 256? */
>> if (data[0] & 1)
>> return 0;
>> } else if (wc == SPI_FLASH_PAGE_264) {
>> /* Already 264? */
>> if ((data[0] & 1) == 0)
>> return 0;
>> } else {
>> debug("Unsupport page configuration!\n");
>> return -1;
>> }
>>
>> /*
>> * 3D, 2A, 80, A6 command seq will configure flash page size 256.
>> * 3D, 2A, 80, A7 command seq will configure flash page size 264.
>> */
>> cmd = 0x3D;
>> if (wc == SPI_FLASH_PAGE_256)
>> data[2] = 0xA6;
>> else if (wc == SPI_FLASH_PAGE_264)
>> data[2] = 0xA7;
>> data[1] = 0x80;
>> data[0] = 0x2A;
>> ret = spi_flash_write_common(flash, &cmd, 1, data, 3);
>> if (ret) {
>> debug("SF: fail to write config register\n");
>> return ret;
>> }
>>
>> /* Check again the page size*/
>> xxxxxxxxxxxxxxxxxx
>>
>> return 0;
>> }
>> #endif
>>
>>> Or I will add a AT45DB special flash driver under Driver Model.
>> Regards,
>> Peng.
>>
> .
>
Regards,
Peng.
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