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

Tue Jun 13 07:44:43 UTC 2017

> On 13 Jun 2017, at 03:40, Kever Yang <kever.yang at rock-chips.com> wrote:
> 
> Hi Simon,
> 
> 
> On 06/09/2017 08:27 PM, Simon Glass wrote:
>> Hi Kever,
>> 
>> On 7 June 2017 at 04:55, Kever Yang <kever.yang at rock-chips.com> wrote:
>>> Simon,
>>> 
>>> 
>>> 
>>> On 06/07/2017 11:15 AM, Simon Glass wrote:
>>>> Hi Kever,
>>>> 
>>>> On 6 June 2017 at 20:41, Kever Yang <kever.yang at rock-chips.com> wrote:
>>>>> 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?
>>>> These ones:
>>>> 
>>>> a079e52d35 rockchip: mkimage: set init_boot_size to avoid confusing the
>>>> boot ROM
>>>> ee2c63912b rockchip: mkimage: force 2KB alignment for init_size
>>>> 99c700c794 rockchip: mkimage: add support for verify_header/print_header
>>>> 
>>>>> 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.
>>>> OK, how did we survive before? What has changed to make this series
>>>> needed?
>>> 
>>> After check with JTAG, I find that I'm wrong with cmd code '00000000',
>>> this is 'andeq r0, r0, r0', but not undefined in armv7, so it can work.
>>> 
>>> I still want this patch set applied because it's better to make all the
>>> Rockchip's
>>> SPL have the same format(with 4-byte TAG space reserved), and the ddr binary
>>> from Rockchip always have pre-padding 4-byte TAG, with this patch set, we
>>> can replace each other easily and work with one mkimage tool.
>> I'm not sure how to apply this since on the other thread[1] Marek says
>> it will break socfpga.
> 
> I know this must break socfpga platform, and as I have said in cover letter,
> I think this patch also break bcm and sunxi platform, I add 'RFC' for this patch
> set because I don't know the detail requirement of hook0 for other 3 platform,
> I'm not asking if this patch set break other 3 platforms or not, but I'm asking for
> the solution for those 3 platform so that we can apply this patch set.

The following platforms have a boot0-hook implemented:

./arch/arm/include/asm/arch-rockchip/boot0.h
./arch/arm/include/asm/arch-bcm235xx/boot0.h
./arch/arm/include/asm/arch-sunxi/boot0.h
./arch/arm/include/asm/arch-bcm281xx/boot0.h
./arch/arm/mach-socfpga/include/mach/boot0.h

> I think my patch is correct in what HOOK0 wants to do, just like Philipp's opinion
> in another mail.
> I hope to get help from maintainer for socfpga, bcm, sunxi platform.
> 
> Thanks,
> - Kever
>> 
>> Would it be possible to change the DDR binary to not include the padding?
>> 
>> Regards,
>> Simon
>> 
>> [1] armv7: move boot hook before '_start'