[U-Boot] Odroid XU3 - exynos5422 - SPL - iRAM/sRAM address

[Suriyan Ramasami]

On Thu, Jan 22, 2015 at 9:51 AM, Kevin Hilman <khilman at kernel.org> wrote:
> Suriyan Ramasami <suriyan.r at gmail.com> writes:
>
>> Hello Kevin,
>>
>> On Wed, Jan 21, 2015 at 4:54 PM, Kevin Hilman <khilman at kernel.org> wrote:
>>> Hi Surijan,
>>>
>>> Suriyan Ramasami <suriyan.r at gmail.com> writes:
>>>
>>>> Hello Sjoerd Simons,
>>>>    A signed BL2 which allows unsigned BL2 chain load is already
>>>> available for experimentation. Refer this link:
>>>> http://forum.odroid.com/viewtopic.php?f=98&t=6147#p58984
>>>> The suriyan.bl2-hkxu3.1212.5422.zip blob contains a signed BL2 which
>>>> allows the same.
>>>>
>>>> The layout of SD card is as follows:
>>>>
>>>> BL1 (1 to 30) 15K
>>>> BL2 (31 to 62) 16K
>>>> indicator block (63 to 64) 1K
>>>> uboot (65 to 2112) 1M
>>>> tzsw (2113 to 2624) 256K
>>>> unsigned BL2 (2625 to 2656) 16K
>>>>
>>>> A non zero in the first byte of the indicator block instructs the
>>>> signed BL2 to load the unsigned BL2 @ offset 2625.
>>>
>>> I took the binaries from your .zip file above and put them on the SD
>>> card for my odroid-xu3 at the offsets above.  I'm using BL1 and TZSW
>>> from the u-boot-hardkernel release[1] and using u-boot-dtb.bin from
>>> my own mainline u-boot build which inclues the odroid-xu3 patches.
>>>
>>> If I leave the indicator block zero'd, everything works fine, and it
>>> boots my version of mainline u-boot without any problems.
>>>
>>> If I then write a non-zero value to the first byte of the indicator
>>> block and write your unsigned BL2 at the appropriate offset, it no
>>> longer boots.  Is the unsigned BL2 supposed to boot u-boot at offset 65
>>> when it's finished as well?
>>>
>>
>> The unsigned SPL from mainline used will be spl/u-boot-spl.bin (raw
>> jump to offset 0 in that file will be pure code without headers)
>
> OK.
>
>> Changes are needed in spl_boot.c to make it next load u-boot-dtb.bin.
>>
>> I shall try to list most of the changes here:
>> 1.arch/arm/cpu/armv7/exynos/spl_boot.c:
>>    The Odroid-XU3's IROM function pointers does not have any code
>> (AFAICT). I checked the locations that are listed in the array table
>> and found all 0's there.
>>    We need to replace function copy_uboot_to_ram() with something
>> similar from HK's file, so that it uses exynos_smc() calls to load the
>> bits from SD card, or we could enable MMC code in SPL (haven't tried
>> it) and use those functions instead.
>>   For quick results,I just forced an SD card read.
>>
>> 2. #define CONFIG_SEC_FW_SIZE (15 << 10) /* 15 KB */
>>  somewhere, so that the start offset for U-Boot is calculated correctly.
>>
>> 3. for chain loading we define CONFIG_SPL_TEXT_BASE to be, say
>> 0x63E00000 so that when its executed the static global pointers are
>> accessed correctly - static struct spl_machine_param machine_param in
>> file smdk5420_spl.c.
>>
>> 4. mem_ctrl_init() hangs in while (val != FOUTBPLL);
>>   One workaround is to use HKs version of this function which again
>> uses some smc calls.
>>
>> With all these changes, SPL chainloading works.
>
> Do you have a patch against mainline u-boot for all these changes?  I'd
> be happy to test.
>

Give me some time and I shall iron out my notes and get back to
creating a patch for this against mainline U-Boot.

>>> How are you debugging your SPL images?
>>>
>>> I tried adding CONFIG_SPL_SERIAL_SUPPORT so I could printf from SPL, but
>>> that doesn't compile because it seems that libfdt support is needed.
>>>
>>
>> I didn't enable SERIAL SUPPORT for debugging. I did study the HK SPL
>> code vs mainline SPL code quite a bit and worked from there.
>> I can try to see if there is an easy way to enable serial printfs.
>
> Are there any GPIO LEDs to blink?
>

It does have some LEDs.

> Thanks,
>
> Kevin