Date: Sun, 3 May 2015 23:10:54 +0200
From: Robert Schwebel <r.schwebel@pengutronix.de>
To: Peter Hurley <peter@hurleysoftware.com>
Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel@pengutronix.de
Subject: earlycon: no match?
Message-ID: <20150503211054.GR15254@pengutronix.de>
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Hi Peter,

with 4.1-rc1, my boxes with early console enabled show something like
this (the example is vexpress, but it for example also happens on an
AM335x board):

  earlycon: no match for ttyAMA0,38400n8

The box was booted with "console=ttyAMA0,38400n8" on the commandline.
If I understand this right, the code in drivers/tty/serial/earlycon.c
calls setup_earlycon() with the string above ("ttyAMA0,38400n8") and
fails to find that string in the "names" part of the __earlycon_table,
because for the pl011 component on vexpress, the early console was
registered in drivers/tty/serial/amba-pl011.c with:

OF_EARLYCON_DECLARE(pl011, "arm,pl011", pl011_early_console_setup);
                    ^^^^^ name

So isn't that trying to match "ttyAMA0" against "arm,pl011"? I have the
feeling that I didn't understand the logic behind that.

Can you elaborate about how this is supposed to work correctly?

Thanks,
rsc
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