[U-Boot] [PATCH v3 04/11] mx6: add boot device support for SPL

[Tim Harvey]

On Wed, May 28, 2014 at 9:38 AM, Nikita Kiryanov <nikita at compulab.co.il> wrote:
> Hi Tim,
> Sorry for the late reply.

no worries - your the only review of this revision thus far ;)

>
>
> On 08/05/14 08:16, Tim Harvey wrote:
>>
>> Add a common spl.c file to support boot device functions needed for SPL
>> such as detecting the boot device.
>>
>> Signed-off-by: Tim Harvey <tharvey at gateworks.com>
>> ---
>> v3:
>>   - added Freescale copyright
>>
>> v2:
>>   - re-base on top of Masahiro Yamada's consolidation patch:
>>     http://patchwork.ozlabs.org/patch/341817/
>>   - moved spl_boot_device() and get_boot_mode() into own common imx spl.c
>> file
>>   - use mem-mapped structure for smbr reg access
>> ---
>
>
> [..snip..]
>
>
>> +               }
>> +               break;
>> +       /* SD/eSD: 8.5.3, Table 8-15  */
>> +       case 0x4:
>> +       case 0x5:
>> +               return BOOT_DEVICE_MMC1;
>> +       /* MMC/eMMC: 8.5.3 */
>> +       case 0x6:
>> +       case 0x7:
>> +               return BOOT_DEVICE_MMC1;
>> +       /* NAND Flash: 8.5.2 */
>> +       case 0x8 ... 0xf:
>> +               return BOOT_DEVICE_NAND;
>> +       }
>> +       return BOOT_DEVICE_NONE;
>> +}
>> +#endif
>> +
>> +#if defined(CONFIG_SPL_MMC_SUPPORT)
>> +/* called from spl_mmc to see type of boot mode for storage (RAW or FAT)
>> */
>> +u32 spl_boot_mode(void)
>> +{
>> +       switch (spl_boot_device()) {
>> +       /* for MMC return either RAW or FAT mode */
>> +       case BOOT_DEVICE_MMC1:
>> +       case BOOT_DEVICE_MMC2:
>
>
> spl_boot_device() returns only BOOT_DEVICE_MMC1. Was the MMC/eMMC case
> supposed to return a BOOT_DEVICE_MMC2?

Its hard to say - I think the use of BOOT_DEVICE_* is very
implementation specific. I don't quite understand why there is a
BOOT_DEVICE_MMC{1,2,2_2} defined in arch/arm/include/asm/spl.h - the
BOOT_DEVICE_MMC2_2 is certainly quite odd. In uboot/common/spl/spl.c
they are all treated the same and spl_mmc_load_image() always assumes
the 'first' mmc device anyway.

In the IMX6 case I'm not sure an SD/uSD card would be treated any
different than an MMC card so it would come down to which specific
device is flagged as the boot device, of which there are 4 sdhc's. So
eventually, one might need to add more BOOT_DEVICE_MMC enums if that
is to be supported. For now, I'm keeping it simple and there is an
issue with IMX6 spl_mmc_load_image() anyway which I plan on addressing
later.

Tim

>
> Aside from this nitpick,
> Acked-by: Nikita Kiryanov <nikita at compulab.co.il>