[PATCH 1/2] ARM: dts: armada388-clearfog: enable spi flash

Hi Russell King,
 
 On jeu., juin 28 2018, Russell King - ARM Linux [off-list ref] wrote:

On Thu, Jun 28, 2018 at 01:47:30PM +0300, Baruch Siach wrote:

quoted

Hi Russell,

On Thu, Jun 28, 2018 at 11:33:20AM +0100, Russell King - ARM Linux wrote:

quoted

On Thu, Jun 28, 2018 at 01:07:59PM +0300, Baruch Siach wrote:

quoted

Thanks for reviewing.

On Thu, Jun 28, 2018 at 10:51:14AM +0100, Russell King - ARM Linux wrote:

quoted

On Thu, Jun 28, 2018 at 10:13:35AM +0300, Baruch Siach wrote:

quoted

The SolidRun Armada 388 SOM has the SPI flash populated by default
unless the customer explicitly asks otherwise. Enable support by
default.

Are you sure about that - at least some of my boards do not have the
SPI flash populated.

&spi1 {
        /* The microsom has an optional W25Q32 on board, connected to CS0 */
...
&spi1 {
        /*
         * Add SPI CS pins for clearfog:
         * CS0: W25Q32 (not populated on uSOM)

I should update this line as well, I guess.

quoted

         * CS1: PIC microcontroller (Pro models)
         * CS2: mikrobus
         */

I wouldn't have written "not populated on uSOM" without having first
taken the uSOM off and physically checked.

Are these production SOMs or development/engineering samples?

I don't remember.

quoted

Ilya Viten from the SolidRun commercial department told me that all production 
SOMs that were shipped to customers have the SPI flash populated.

Yes, Jon confirms that.

quoted

This is just the default value for the common case.

Has it been tested with boards that don't have the SPI flash populated?
That needs to happen to make sure that this doesn't cause a regression.

I don't have such a SOM handy. I can try to "produce" one next week.

I tested a modified DT with the 'reg' property set to 1 to simulate an 
unpopulated SPI flash. The driver probe seems to fail gracefully:

  m25p80 spi1.1: unrecognized JEDEC id bytes: ff, ff, ff

Is this test sufficient to ensure the safety of this patch?

Yes, that's fine, thanks for checking.

Acked-by: Russell King <redacted>

Gregory, please add my acked-by to your hasty commit, thanks.

Done!

Thanks,

Gregory

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