[U-Boot] [PATCH] am33xx, spl, siemens: enable debug uart output again

[Heiko Schocher <hs@denx.de>]

Hello Tom,

Am 06.03.2015 08:24, schrieb Heiko Schocher:
> Hello Tom,
>
> Am 05.03.2015 15:50, schrieb Tom Rini:
>> On Thu, Mar 05, 2015 at 09:46:50AM +0100, Heiko Schocher wrote:
>>> Hello Tom,
>>>
>>> Am 05.03.2015 07:22, schrieb Heiko Schocher:
>>>> Hello Tom,
>>>>
>>>> Am 04.03.2015 17:40, schrieb Tom Rini:
>>>>> On Wed, Mar 04, 2015 at 08:42:58AM +0100, Heiko Schocher wrote:
>>>>>> Hello Tom,
>>>>>>
>>>>>> Am 02.03.2015 14:59, schrieb Tom Rini:
>>>>>>> On Mon, Mar 02, 2015 at 07:56:41AM +0100, Heiko Schocher wrote:
>>>>>>>> Hello Simon,
>>>>>>>>
>>>>>>>> Am 24.02.2015 14:31, schrieb Simon Glass:
>>>>>>>>> Hi Heiko,
>>>>>>>>>
>>>>>>>>> On 23 February 2015 at 23:18, Heiko Schocher <hs@denx.de> wrote:
>>>>>>>>>> a6b541b090: TI ARMv7: Don't use GD before crt0.S has set it
>>>>>>>>>>
>>>>>>>>>> moves the init of the debug uart at the very end of SPL code.
>>>>>>>>>> Enable it for the siemens board earlier, as they print
>>>>>>>>>> ddr settings ... all debug output before board_init_r()
>>>>>>>>>> is here currently useless. Maybe we must rework this
>>>>>>>>>> globally?
>>>>>>>>>
>>>>>>>>> Assuming we are talking about U-Boot proper, the DDR init should
>>>>>>>>> happen in board_init_f(), specifically dram_init(). so I think this
>>>>>>>>> code should be updated.
>>>>>>>>>
>>>>>>>>> If it is SPL, then DDR init should happen in SPL's board_init_f().
>>>>>>>>
>>>>>>>> It is in SPL...
>>>>>>>>
>>>>>>>> sdram_init() is called from:
>>>>>>>>
>>>>>>>> ./arch/arm/cpu/armv7/am33xx/board.c from s_init() ...
>>>>>>>>
>>>>>>>>> I sent a series a few weeks ago (available at u-boot-dm branch
>>>>>>>>> spl-working) related to this topic:
>>>>>>>>>
>>>>>>>>> http://patchwork.ozlabs.org/patch/438581/
>>>>>>>>
>>>>>>>> Ah ... Hmm... so "./arch/arm/cpu/armv7/am33xx/board.c" needs
>>>>>>>> a rework, right?
>>>>>>>>
>>>>>>>> Is a simple rename s_init() -> board_init_f() correct?
>>>>>>>
>>>>>>> Right so, no, we can't just rename s_init to board_init_f.  This is what
>>>>>>> I was talking about in the thread about the function Hans wants to add
>>>>>>> to enable some bits in CP15 on sunxi, iirc.
>>>>>>>
>>>>>>> In short, armv7 has a different set of abstraction hooks than the
>>>>>>> previous ARM cores (armv8 followed what we have for v7) and I'm not
>>>>>>> convinced in the end that it really won us anything.  See
>>>>>>> http://lists.denx.de/pipermail/u-boot/2015-January/202350.html
>>>>>>>
>>>>>>> For today you need to rework the Siemens code to print out the DDR
>>>>>>> values (when desired) in spl_board_init() as we do not, or will not
>>>>>>> shortly, have gd prior to board_init_f running.
>>>>>>
>>>>>> Hmm... first I thought, ok, no problem, move the output from the RAM
>>>>>> parameters to spl_board_init() ... but thats only the half of the
>>>>>> story ... They read the RAM parameters from an i2c eeprom, and if
>>>>>> there are errors, they print this errors ... currently this does
>>>>>> not work, and thats I think the more important case ... and I could
>>>>>> not move this error printfs to somewhere, because if RAM is not
>>>>>> working ... there is no later ...
>>>>>>
>>>>>> So I have to enable the console early ... maybe I missed something,
>>>>>> but this worked fine in the past (and I think we should not break
>>>>>> this, as this is an essential feature).
>>>>>
>>>>> OK, I missed something too.  I think this gets better now once I merge
>>>>> Simon's SPL series as we do all of this from board_init_f() and the
>>>>> siemens code should just work again.
>>>>
>>>> Yes, just saw your patch ;-)
>>>>
>>>> If they are in mainline (or do you have them somewhere in a git repo?),
>>>> I test it again on the dxr2 board, thanks!
>>>
>>> If I am correct, all needed patches from you are in mainline, just
>>> tried this on the dxr2 board ... but I still need:
>>>
>>> diff --git a/board/siemens/common/board.c b/board/siemens/common/board.c
>>> index a39cbd0..8724604 100644
>>> --- a/board/siemens/common/board.c
>>> +++ b/board/siemens/common/board.c
>>> @@ -40,6 +40,11 @@ void set_uart_mux_conf(void)
>>>
>>>   void set_mux_conf_regs(void)
>>>   {
>>> +       /* enable early the console */
>>> +       gd->baudrate = CONFIG_BAUDRATE;
>>> +       serial_init();
>>> +       gd->have_console = 1;
>>> +
>>>          /* Initalize the board header */
>>>          enable_i2c0_pin_mux();
>>>          i2c_set_bus_num(0);
>>>
>>> to see the console output ...
>>
>> Yes, if you want console prior to spl_board_init() then you need to do
>> that where you are.
>>
>
> Ah, ok... so this patch is OK?

Just found this thread again, as I want to post updates for the am335x
based siemens boards ... Is this patch [1] Ok, and can get applied?

Thanks!

bye,
Heiko
[1] Patchwork [U-Boot] am33xx, spl, siemens: enable debug uart output again
https://patchwork.ozlabs.org/patch/446644/

Hups... found this patch in patchwork marked as RFC and Delegated
to me ... ?
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