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console vs earlycon ?

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Hi.




I think there are three places where console could be enabled.

[1] earlycon

Each driver entry is declared with
EARLYCON_DECLARE()  or OF_EARLYCON_DECLARE()



[2] console_init()

Each entry is declared with  console_initcall()



[3]  when driver is probed
The console is usually enabled at this point
unless some special treatment is done.




My question is about [2].

I am using 8250-ish UART device.


I noticed univ8250_console_match() and univ8250_console_setup()
always fail at the point of [2] unless early_serial_setup() has been
called in advance;
however, it looks like early_serial_setup() is only used for old platforms.

So, console cannot be enabled at [2] for modern platforms.


My questions are:

 -  Given that earlycon can be now available for major architectures such ARM,
     [2] will be deprecated at some point in the future?

 - I am implementing  earlycon  for my own UART driver.
   Is it meaningless to implement  console_initcall()  as well as earlycon?



-- 
Best Regards
Masahiro Yamada
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Thread

console vs earlycon ? Masahiro Yamada <yamada.masahiro@socionext.com> - 2015-10-21 10:30 +0200
  Re: console vs earlycon ? Arnd Bergmann <arnd@arndb.de> - 2015-10-21 11:00 +0200
    Re: console vs earlycon ? Masahiro Yamada <yamada.masahiro@socionext.com> - 2015-10-21 11:10 +0200
      Re: console vs earlycon ? Arnd Bergmann <arnd@arndb.de> - 2015-10-21 11:30 +0200
        Re: console vs earlycon ? Masahiro Yamada <yamada.masahiro@socionext.com> - 2015-10-21 11:40 +0200
          Re: console vs earlycon ? Arnd Bergmann <arnd@arndb.de> - 2015-10-21 12:40 +0200
            Re: console vs earlycon ? Peter Hurley <peter@hurleysoftware.com> - 2015-10-21 16:00 +0200
              Re: console vs earlycon ? Arnd Bergmann <arnd@arndb.de> - 2015-10-21 16:20 +0200
                Re: console vs earlycon ? Peter Hurley <peter@hurleysoftware.com> - 2015-10-21 17:40 +0200
                Re: console vs earlycon ? Arnd Bergmann <arnd@arndb.de> - 2015-10-21 21:10 +0200
                Re: console vs earlycon ? Peter Hurley <peter@hurleysoftware.com> - 2015-10-21 21:30 +0200
                Re: console vs earlycon ? Arnd Bergmann <arnd@arndb.de> - 2015-10-22 01:00 +0200
  Re: console vs earlycon ? Peter Hurley <peter@hurleysoftware.com> - 2015-10-21 15:30 +0200
    Re: console vs earlycon ? Masahiro Yamada <yamada.masahiro@socionext.com> - 2015-10-22 06:50 +0200

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