[U-Boot] [PATCH 1/2 v1] sf: probe: Add support Atmel AT45DB series devices special commands

[Peng Fan <Peng.Fan@freescale.com>]

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@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@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.