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

[Heiko Schocher]

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 at 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 ...

bye,
Heiko
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