Re: Boot on eMMC

[Gary Thomas <gary@mlbassoc.com>]

On 2015-04-14 09:05, Otavio Salvador wrote:
> On Tue, Apr 14, 2015 at 12:04 PM, Gary Thomas <gary@mlbassoc.com> wrote:
>> On 2015-04-14 09:00, Otavio Salvador wrote:
>>>
>>> On Tue, Apr 14, 2015 at 11:58 AM, Gary Thomas <gary@mlbassoc.com> wrote:
>>>>
>>>> On 2015-04-14 08:28, Otavio Salvador wrote:
>>>>>
>>>>>
>>>>> On Tue, Apr 14, 2015 at 11:12 AM, Shanx <shanx@legtux.org> wrote:
>>>>>>
>>>>>>
>>>>>> Hello,
>>>>>> I've tried a lot of things, but I can't boot on eMMC. I've flashed it
>>>>>> from
>>>>>> u-boot, or from the system (booted from the sdcard). For exemple, I've
>>>>>> tried
>>>>>> : dd if=rootfs.sdcard of=/dev/mmcblk3
>>>>>> I've also tried to flash only u-boot.imx (with dd and seek=2)
>>>>>>
>>>>>> When booting on eMMC (with the boot switch setup given on the Linux
>>>>>> User
>>>>>> Guide), nothing append. Any idea why ?
>>>>>
>>>>>
>>>>>
>>>>> eMMC has some details which differ from the uSD normal usage. Mainly
>>>>> regarding the use of Boot Partitions. So you must to write it to the
>>>>> boot partition otherwise it won't work.
>>>>>
>>>>
>>>> I'm not sure this is correct.  I have an i.MX6Q board which has
>>>> eMMC on SD4 and SD on SD3 and I can boot from either, using the
>>>> same command to install U-Boot
>>>>     dd if=/tmp/disk/${UBOOT_NAME} of=${DISK} seek=2 bs=512 conv=notrunc
>>>>
>>>> Maybe it's a difference in the eMMC device (mine is Sandisk SDIN5
>>>> (or7)C2-32G-L)
>>>
>>>
>>> It depends if Boot Partition is enabled or not.
>>>
>>
>> Is that an i.MX6 setting?
>
> No; it is eMMC 4.41 (or later) one if IIRC. There are some fields
> exposed in sysfs and also a mmc-utils package at meta-oe.
>

Interesting, I'll look at this but my boards have boot partitions:

mmc0: new high speed DDR MMC card at address 0001
mmcblk0: mmc0:0001 SEM32G 29.1 GiB
mmcblk0boot0: mmc0:0001 SEM32G partition 1 4.00 MiB
mmcblk0boot1: mmc0:0001 SEM32G partition 2 4.00 MiB
usb 1-1: new high-speed USB device number 2 using ci_hdrc
mmcblk0rpmb: mmc0:0001 SEM32G partition 3 4.00 MiB
  mmcblk0: p1 p2
  mmcblk0boot1: unknown partition table
  mmcblk0boot0: unknown partition table

As I said, I install U-Boot directly to block 2 of the device,
not to any of the "boot" partitions.

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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