[U-Boot] [PATCH v2 2/3] Allow displaying the U-Boot banner on a video display

[Bin Meng]

Hi Simon,

On Mon, Jun 12, 2017 at 11:17 PM, Simon Glass <sjg at chromium.org> wrote:
> Hi Bin,
>
> On 12 June 2017 at 09:13, Bin Meng <bmeng.cn at gmail.com> wrote:
>> Hi Simon,
>>
>> On Sun, Jun 11, 2017 at 1:59 AM, Simon Glass <sjg at chromium.org> wrote:
>>> At present the U-Boot banner is only displayed on the serial console. If
>>> this is not visible to the user, the banner does not show. Some devices
>>> have a video display which can usefully display this information.
>>>
>>> Add a banner which is printed after relocation only on non-serial devices
>>> if CONFIG_DISPLAY_BOARDINFO_LATE is defined.
>>>
>>> Signed-off-by: Simon Glass <sjg at chromium.org>
>>> ---
>>>
>>> Changes in v2:
>>> - Reword function comment for console_announce_r() slighty
>>>
>>>  common/board_r.c  |  1 +
>>>  common/console.c  | 15 +++++++++++----
>>>  include/console.h | 12 ++++++++++++
>>>  3 files changed, 24 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/common/board_r.c b/common/board_r.c
>>> index 15977e4bca..ff11eba5d3 100644
>>> --- a/common/board_r.c
>>> +++ b/common/board_r.c
>>> @@ -846,6 +846,7 @@ static init_fnc_t init_sequence_r[] = {
>>>  #endif
>>>         console_init_r,         /* fully init console as a device */
>>>  #ifdef CONFIG_DISPLAY_BOARDINFO_LATE
>>> +       console_announce_r,
>>>         show_board_info,
>>>  #endif
>>>  #ifdef CONFIG_ARCH_MISC_INIT
>>> diff --git a/common/console.c b/common/console.c
>>> index 1232808df5..3fcd7ce66b 100644
>>> --- a/common/console.c
>>> +++ b/common/console.c
>>> @@ -202,7 +202,6 @@ static void console_putc(int file, const char c)
>>>         }
>>>  }
>>>
>>> -#if CONFIG_IS_ENABLED(PRE_CONSOLE_BUFFER)
>>
>> Why removing this? Without PRE_CONSOLE_BUFFER, I doubt it works.
>
> I want to be able to call the function below. It seems to work OK and
> it doesn't rely on that option.
>

See comments below.

>>
>>>  static void console_puts_noserial(int file, const char *s)
>>>  {
>>>         int i;
>>> @@ -214,7 +213,6 @@ static void console_puts_noserial(int file, const char *s)
>>>                         dev->puts(dev, s);
>>>         }
>>>  }
>>> -#endif
>>>
>>>  static void console_puts(int file, const char *s)
>>>  {
>>> @@ -248,13 +246,11 @@ static inline void console_putc(int file, const char c)
>>>         stdio_devices[file]->putc(stdio_devices[file], c);
>>>  }
>>>
>>> -#if CONFIG_IS_ENABLED(PRE_CONSOLE_BUFFER)
>>>  static inline void console_puts_noserial(int file, const char *s)
>>>  {
>>>         if (strcmp(stdio_devices[file]->name, "serial") != 0)
>>>                 stdio_devices[file]->puts(stdio_devices[file], s);
>>>  }
>>> -#endif
>>>
>>>  static inline void console_puts(int file, const char *s)
>>>  {
>>> @@ -699,6 +695,17 @@ static void console_update_silent(void)
>>>  #endif
>>>  }
>>>
>>> +int console_announce_r(void)
>>> +{
>>> +       char buf[DISPLAY_OPTIONS_BANNER_LENGTH];
>>> +
>>> +       display_options_get_banner(false, buf, sizeof(buf));
>>> +
>>> +       console_puts_noserial(stdout, buf);

Then I think we should do something like this:

int console_announce_r(void)
{
#ifndef CONFIG_PRE_CONSOLE_BUFFER
        char buf[DISPLAY_OPTIONS_BANNER_LENGTH];

        display_options_get_banner(false, buf, sizeof(buf));
        console_puts_noserial(stdout, buf);
#endif
}

If we don't do this, there will be duplicated U-Boot version string
shown on the screen if CONFIG_PRE_CONSOLE_BUFFER is defined.

>>> +
>>> +       return 0;
>>> +}
>>> +
>>>  /* Called before relocation - use serial functions */
>>>  int console_init_f(void)
>>>  {
>>> diff --git a/include/console.h b/include/console.h
>>> index 3d37f6a53b..cea29ed6dc 100644
>>> --- a/include/console.h
>>> +++ b/include/console.h
>>> @@ -42,6 +42,18 @@ void console_record_reset(void);
>>>   */
>>>  void console_record_reset_enable(void);
>>>
>>> +/**
>>> + * console_announce_r() - print a U-Boot console on non-serial consoles
>>> + *
>>> + * When U-Boot starts up with a display it generally does not announce itself
>>> + * on the display. The banner is instead emitted on the UART before relocation.
>>> + * This function prints a banner on devices which (we assume) did not receive
>>> + * it before relocation.
>>> + *
>>> + * @return 0 (meaning no errors)
>>> + */
>>> +int console_announce_r(void);
>>> +
>>>  /*
>>>   * CONSOLE multiplexing.
>>>   */
>>> --
>>
>> And I see another (same) patch @
>> https://patchwork.ozlabs.org/patch/769426/ which got applied, but this
>> one was sent later than the applied one. I am confused..
>
> Another patch in this series caused a breakage using a long BUILD_TAG
> due to a bug in how the snprintf() calls were done. So I dropped two
> patches from that series and sent this series instead.
>
> It wasn't noticed since I don't use BUILD_TAG and no tests were in
> place. It just happened that Stephen Warren has automated testing that
> caught it before it was pulled to mainline.

OK, thanks for the clarification.

Regards,
Bin