[PATCH v9] mtd: spi-nor: Add support for S3AN spi-nor devices

[Ricardo Ribalda Delgado]

Hi Cyrille

I have found a bug on the way the address is generated in special
mode. Do you prefer a v9 of this patch or a patch?

Regards!

On Tue, Dec 13, 2016 at 5:30 PM, Cyrille Pitchen
<cyrille.pitchen at wedev4u.fr> wrote:
> Le 13/12/2016 à 08:53, Marek Vasut a écrit :
>> On 12/02/2016 12:31 PM, Ricardo Ribalda Delgado wrote:
>>> Xilinx Spartan-3AN FPGAs contain an In-System Flash where they keep
>>> their configuration data and (optionally) some user data.
>>>
>>> The protocol of this flash follows most of the spi-nor standard. With
>>> the following differences:
>>>
>>> - Page size might not be a power of two.
>>> - The address calculation (default addressing mode).
>>> - The spi nor commands used.
>>>
>>> Protocol is described on Xilinx User Guide UG333
>>>
>>> Reviewed-by: Cyrille Pitchen <cyrille.pitchen at atmel.com>
>>> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda at gmail.com>
>>> Cc: Boris Brezillon <boris.brezillon at free-electrons.com>
>>> Cc: Brian Norris <computersforpeace at gmail.com>
>>> Cc: Marek Vasut <marek.vasut at gmail.com>
>>
>> [...]
>>
>>> +static int s3an_nor_scan(const struct flash_info *info, struct spi_nor *nor)
>>> +{
>>> +    int ret;
>>> +    u8 val;
>>> +
>>> +    ret = nor->read_reg(nor, SPINOR_OP_XRDSR, &val, 1);
>>> +    if (ret < 0) {
>>> +            dev_err(nor->dev, "error %d reading XRDSR\n", (int) ret);
>>> +            return ret;
>>> +    }
>>> +
>>> +    nor->erase_opcode = SPINOR_OP_XSE;
>>> +    nor->program_opcode = SPINOR_OP_XPP;
>>> +    nor->read_opcode = SPINOR_OP_READ;
>>> +    nor->flags |= SNOR_F_NO_OP_CHIP_ERASE ;
>>
>> NIT: You have an extra space before ;        ^
>>
>>> +
>>> +    /*
>>> +     * This flashes have a page size of 264 or 528 bytes (known as
>>> +     * Default addressing mode). It can be changed to a more standard
>>> +     * Power of two mode where the page size is 256/512. This comes
>>> +     * with a price: there is 3% less of space, the data is corrupted
>>> +     * and the page size cannot be changed back to default addressing
>>> +     * mode.
>>> +     *
>>> +     * The current addressing mode can be read from the XRDSR register
>>> +     * and should not be changed, because is a destructive operation.
>>> +     */
>>> +    if (val & XSR_PAGESIZE) {
>>> +            /* Flash in Power of 2 mode */
>>> +            nor->page_size = (nor->page_size == 264) ? 256 : 512;
>>> +            nor->mtd.writebufsize = nor->page_size;
>>> +            nor->mtd.size = 8 * nor->page_size * info->n_sectors;
>>> +            nor->mtd.erasesize = 8 * nor->page_size;
>>> +    } else {
>>> +            /* Flash in Default addressing mode */
>>> +            nor->flags |= SNOR_F_S3AN_ADDR_DEFAULT;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>
>> Looks great otherwise:
>> Reviewed-by: Marek Vasut <marek.vasut at gmail.com>
>>
> Applied to git://github.com/spi-nor/linux.git
>
> I've removed the additional SPACE before ';' as reported by Marek.
>
> Thanks!



-- 
Ricardo Ribalda