[PATCH v3 0/3] spi-nor: Add support for Intel SPI serial flash controller

[Stefan Roese]

On 05.10.2016 13:18, Mika Westerberg wrote:
> On Wed, Oct 05, 2016 at 01:11:39PM +0200, Stefan Roese wrote:
>> [    3.654301] intel-spi intel-spi: OPMENU0=0x00009f0b
>> [    3.654304] intel-spi intel-spi: OPMENU1=0x00000000
>> [    3.654306] intel-spi intel-spi: BCR=0x00000009
>> [    3.654308] intel-spi intel-spi: Protected regions:
>> [    3.654313] intel-spi intel-spi: Flash regions:
>> [    3.654316] intel-spi intel-spi:  00 base: 0x00000000 limit: 0x00000fff
>> [    3.654320] intel-spi intel-spi:  01 base: 0x00300000 limit: 0x007fffff
>> [    3.654323] intel-spi intel-spi:  02 base: 0x00001000 limit: 0x002fffff
>> [    3.654325] intel-spi intel-spi:  03 disabled
>> [    3.654328] intel-spi intel-spi:  04 disabled
>> [    3.654330] intel-spi intel-spi: Using SW sequencer for register access
>> [    3.657488] intel-spi intel-spi: s25fl064k (8192 Kbytes)
>> [    3.677241] Creating 1 MTD partitions on "intel-spi":
>> [    3.682310] 0x000000000000-0x000000800000 : "BIOS"
>
> Cool!
>
>> So how do you suggest to support such BayTrail boards booting
>> via U-Boot as bootloader? Should U-Boot write something into
>> these OPMENU0/1 registers before booting into Linux?
>
> Typically it's the BIOS who does that so I guess in your case it should
> be U-Boot then. I would not like to add that part to the driver itself
> unless absolutely necessary ;-)

Sure, I can definitely add something here in U-Boot. Since I'm
pretty new to this driver / controller and its interface to the BIOS,
could you perhaps suggest those values please? To enable the Linux
driver with full read-write support to such chips?

Thanks,
Stefan