[U-Boot] [RFC PATCH 0/5] move boot0 hook in the beginning for armv7

[Kever Yang]

Simon,


On 06/07/2017 05:08 AM, Simon Glass wrote:
> Hi Kever,
>
> On 31 May 2017 at 04:50, Kever Yang <kever.yang at rock-chips.com> wrote:
>> I think the boot0 hook is suppose to add some data in the very beginning
>> of the SPL image, am I right?
>>
>> Rockchip SoCs bootrom design is like this:
>> - First 2KB or 4KB internal memory is for bootrom stack and heap;
>> - Then the first 4-byte suppose to be a TAG like 'RK33';
>> - The the following memory address end with '0004' is the first
>>    instruction load and running by bootrom;
>>
>> Example for RK3288:
>> Before this patch set, the SPL_TEXT_BASE is ff704004, and image write to
>> media device after mkimage like this:
>>
>> ff704000: 32334b52 00000000 00000000 00000000    RK32............
>> ff704010: 00000000 00000000 00000000 00000000    ................
>> ff704020: ea00000f e59ff014 e59ff014 e59ff014    ................
>> ff704030: e59ff014 e59ff014 e59ff014 e59ff014    ................
>>
>> Where the first instruction from bootrom is '00000000', which is a
>> undefined instruction.
>> The '_start' and 'reset' have to align to 0x20 for the requirement of
>> VBAR, the memory offset '004'~'01c' are filled with '00000000'.
>>
>> We can use the boot0 hook to fix this issue, after this patch set,
>> the SPL_TEXT_BASE is ff704000 and image write to media device after
>> mkimage like this:
>>
>> ff704000: 32334b52 ea00001d e320f000 e320f000    RK32...... ... .
>> ff704010: e320f000 e320f000 e320f000 e320f000    .. ... ... ... .
>> ff704020: ea000016 e59ff014 e59ff014 e59ff014    ................
>> ff704030: e59ff014 e59ff014 e59ff014 e59ff014    ................
>>
>> The first instruction from bootrom is a 'b reset', and memory of
>> '008'~'01c' are filled with 'nop' instruction.
>>
>> This patch set does not provide patch for socfpga, bcm and sunxi SoCs which also
>> enable BOOT0_HOOK, so this is a RFC patch, please advice how to make it
>> compatible with those three platforms.
>>
>>
>>
>> Kever Yang (5):
>>    armv7: move boot hook before '_start'
>>    rockchip: boot0: align to 0x20 for armv7 '_start'
>>    rockchip: enable BOOT0_HOOK for SoCs
>>    rockchip: configs: use aligned address for SPL_TEXT_BASE
>>    rockchip: mkimage: use spl_boot0 for all Rockchip SoCs
>>
>>   arch/arm/include/asm/arch-rockchip/boot0.h |  9 ++++++++-
>>   arch/arm/lib/vectors.S                     | 19 ++++++++++---------
>>   arch/arm/mach-rockchip/Kconfig             |  3 +++
>>   include/configs/rk3036_common.h            |  2 +-
>>   include/configs/rk3288_common.h            |  2 +-
>>   tools/rkcommon.c                           |  8 ++++----
>>   6 files changed, 27 insertions(+), 16 deletions(-)
>>
>> --
>> 1.9.1
>>
> Do will still need this series now that (I think) we have a fix for
> the return-to-brom feature in u-boot-rockchip/master?

Could you point me out exactly which fix do you talking about?

This is not about return-to-brom, it's about the first instruction from 
Bootrom to SPL.
So this is need for all Rockchip armv7 SoCs.

Thanks,
- Kever
> Regards,
> Simon
>