Raspberry Pi Compute Module

[Stefan Wahren]

Hi Stephen,

Am 22.07.2015 um 05:41 schrieb Stephen Warren:
> On 07/17/2015 11:08 AM, Stefan Wahren wrote:
>> Hi all,
>>
>> is there anyone working on Mainline support for the Compute Module?
>>
>> I noticed the downstream kernel already has a bcm2708-rpi-cm.dtsi
>
> It is probably close enough that you can simply use bcm2835-rpi-b.dtb
> for the CM too, for testing at least.
>
> I just tried this with latest U-Boot and a 4.2.0-rc3 kernel. The eMMC
> works fine in U-Boot, but the kernel can't access it for some reason,
> failing with e.g.:
>
> [    3.110503] Waiting for root device /dev/mmcblk0p2...
> [    3.123895] mmc0: MAN_BKOPS_EN bit is not set
> [    3.132264] mmc0: error -110 whilst initialising MMC card
> [    3.788447] cfg80211: Calling CRDA to update world regulatory domain
> [    4.204078] mmc0: MAN_BKOPS_EN bit is not set
> [    4.212748] mmc0: error -110 whilst initialising MMC card
> [    5.283981] mmc0: MAN_BKOPS_EN bit is not set
> [    5.292657] mmc0: error -110 whilst initialising MMC card
>
> I had hoped that the kernel fixes for the VC MMU high address bits (via
> the dma-ranges property in DT) would fix this, but I guess not since it
> still doesn't work.
>

thank your for testing.

Does defining the bus width as in bcm2708-rpi-cm.dtsi change anything?

&mmc {
	status = "okay";
	bus-width = <4>;
};

Regards
Stefan