[U-Boot] [RFC 0/5] sf: Update spi-nor framework

[Vignesh R]

Hi Jagan,

On Tuesday 12 December 2017 01:07 PM, Jagan Teki wrote:
[...]
>>>> Prabhakar Kushwaha (5):
>>>>   sf: Add support of 1-2-2, 1-4-4 IO READ protocols
>>>>   sf: add method to support memory size above 128Mib
>>>>   sf: parse Serial Flash Discoverable Parameters (SFDP) tables
>>>>   sf: fsl_qspi: Add support of fsl_qspi_set_mode
>>>>   sf: fsl_quadspi: Configue LUT based on padding information
>>>>
>>>>  drivers/mtd/spi/sf_internal.h   | 230 +++++++++++++++-
>>>>  drivers/mtd/spi/spi_flash.c     | 574
>>> +++++++++++++++++++++++++++++++++++++++-
>>>>  drivers/spi/fsl_qspi.c          |  85 +++++-
>>>>  include/spi_flash.h             |   2 +
>>>>  5 files changed, 875 insertions(+), 18 deletions(-)
>>>>
>>>
>>> Could you rather port the entire SPI NOR framework from Linux 4.14 ?
>>> That'd make more sense than porting bits and pieces on top of the
>>> current crappy code IMO.
>>
>> I agree with you. Linux 4.14 SPI NOR framework should be ported.
>> I may not able to do this because of bandwidth and lack of expertise.
>> I will request Jagan (custodian) to look into this.
>>
>> This RFC patch-set can easily be applied to existing and  ported Linux SPI NOR framework when it gets available.
>>
>> For now, I think these patches(the next version) with the existing framework can be reviewed and accepted.
>> Please help to share your views.
>>
>> For next version of this patch set, I will be working on testing  it to enable other flashes.
>> It will also help Jagan during 4.14 porting.
>> Jagan, your views?
> 
> direct-porting from Linux is not so optimal(not well suited for U-Boot
> design) as I've tried before. We're working on the dm-driven spi-nor.
> So I will continue to review your patches on current code and will see
> how we can merge the same once dm-spi-nor available.

Many of the newer SPI NOR flashes such as MT35x do not support U-Boot's
legacy way of accessing >128Mb region.
Are you planning to submit dm-spi-nor anytime soon? If not, then IMO, at
least patch 2/5 is worth considering for now.



-- 
Regards
Vignesh