[U-Boot] [PATCH v1] cmd/sf: probe flash with speed of last known flash or speed from devicetree

[Vignesh R]

On Wednesday 24 August 2016 07:40 PM, Hannes Schmelzer wrote:
> On 08/24/2016 02:21 PM, Hannes Schmelzer wrote:
>> On 08/24/2016 01:12 PM, Vignesh R wrote:
>>>
>>> On Wednesday 24 August 2016 04:21 PM, Hannes Schmelzer wrote:
>>>> On 08/24/2016 12:35 PM, Vignesh R wrote:

[...]

>>> AFAIU, saveenv() uses CONFIG_ENV_SPI_MAX_HZ only when
>>> CONFIG_DM_SPI_FLASH is not defined. Could please explain how
>>> CONFIG_ENV_SPI_MAX_HZ takes precedence over spi-max-frequency during sf
>>> probe?
>> Thanks the discussion, I think we coming closer to the problem.
>> Your'e right saveenv() behaves as you described, but not so
>> env_relocate_spec().
>>
>> There the flash is probed like this:
>>     env_flash = spi_flash_probe(CONFIG_ENV_SPI_BUS, CONFIG_ENV_SPI_CS,
>>             CONFIG_ENV_SPI_MAX_HZ, CONFIG_ENV_SPI_MODE);
>>
>> and thats the point where some existing dt node becomes modified with
>> those values. Thats probably wrong doing so.
>>
>> I think there should be same logic applied as in saveen().
>Tested again, and confirming this behaviour.

Yeah, I think relocate_spec() was not updated during dm conversion.

>>
>> Just for testing i fixed the probe there.
>> Now i'm a bit confused about that the function
>> spi_find_chip_select(bus, cs, &dev) in spi-uclass doesn't find child
>> devices on the spi node.
>> Instead there a new flash binding is created.
>> spi_get_bus_and_cs: Binding new device 'spi_flash at 0:0', busnum=0,
>> cs=0, driver=spi_flash_std
> Debugged into DM and found out that my devicetree didn't represent a
> valid flash-child.
> I've now modified it to:
> 
> => fdt print spi0
> spi at e000d000 {
>         clock-names = "ref_clk", "pclk";
>         clocks = <0x00000001 0x0000000a 0x00000001 0x0000002b>;
>         compatible = "xlnx,zynq-qspi-1.0";
>         status = "okay";
>         interrupt-parent = <0x00000003>;
>         interrupts = <0x00000000 0x00000013 0x00000004>;
>         reg = <0xe000d000 0x00001000>;
>         #address-cells = <0x00000001>;
>         #size-cells = <0x00000000>;
>         u-boot,dm-pre-reloc;
>         spi-max-frequency = <0x05f5e100>;
>         spiflash at 0 {
>                 u-boot,dm-pre-reloc;
>                 compatible = "spidev", "spi-flash";

Shouldn't this be: compatible = "spansion,S25FL256S_64K", "spi-flash";
as per doc/device-tree-bindings/mtd/spi/spi-flash.txt


-- 
Regards
Vignesh