[PATCH v7 05/21] arm: mvebu: x530: Use tiny SPI NOR

[Chris Packham]

Hi Pratyush,

On 5/09/20 3:39 am, Pratyush Yadav wrote:
> Chris,
>
> On 04/09/20 09:04PM, Pratyush Yadav wrote:
>> The SPI NOR core will get Octal DTR in following commits. This has
>> presented a significant challenge of keeping the SPL size in check on
>> the x530 platform.
>>
>> On a previous iteration of the series, adding a set of compile-time
>> switches got the build working. But rebasing on the latest master breaks
>> the build again. We are fighting a losing battle here. Every addition to
>> either the SPI NOR core in the future, or any other core part of U-Boot
>> will potentially lead to the SPL size going beyond the limit and the
>> build failing.
>>
>> To combat this we will have to keep adding more and more compile-time
>> switches, increasing the complexity of the code in the process. This is
>> not sustainable. So use tiny SPI NOR instead. It is designed with
>> size-limited SPL binaries in mind, and will afford us more breathing
>> room.
>>
>> To enable tiny SPI NOR, CONFIG_SPI_FLASH_BAR has to be disabled.
>>
>> Signed-off-by: Pratyush Yadav <p.yadav at ti.com>
>> ---
>>   configs/x530_defconfig | 1 -
>>   1 file changed, 1 deletion(-)
> Can you please test these changes on your board and confirm that tiny
> SPI NOR works for you?

It booted OK but when I try to write something to SPI flash I get an error

=> sf probe
SF: Detected n25q128a13 with page size 256 Bytes, erase size 4 KiB, 
total 16 MiB
=> sf update ${fileaddr} 0 ${filesize} device 0 offset 0x0, size 0x100000
SPI flash failed in erase step

=> sf erase 0 0x100000
SF: 1048576 bytes @ 0x0 Erased: ERROR

Unfortunately I didn't test this before applying your series so I'm not 
sure if it is because of your changes or a preexisting issue with 
v2020.10-rc3

>   
>> diff --git a/configs/x530_defconfig b/configs/x530_defconfig
>> index 890c94b5c1..0570dbe9ea 100644
>> --- a/configs/x530_defconfig
>> +++ b/configs/x530_defconfig
>> @@ -62,7 +62,6 @@ CONFIG_SYS_NAND_USE_FLASH_BBT=y
>>   CONFIG_NAND_PXA3XX=y
>>   CONFIG_SF_DEFAULT_BUS=1
>>   CONFIG_SF_DEFAULT_SPEED=50000000
>> -CONFIG_SPI_FLASH_BAR=y
>>   CONFIG_SPI_FLASH_MACRONIX=y
>>   CONFIG_SPI_FLASH_STMICRO=y
>>   CONFIG_SPI_FLASH_SST=y