Commit Graph

12 Commits

Author SHA1 Message Date
Peter Hurley 66c53aaa9c earlycon: Revert log warnings
Log warnings meant to help diagnose problems setting up earlycon
are reporting false positives for 'console='. Revert to the
previous behavior which reported nothing.

Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-08 14:20:50 +02:00
Peter Hurley 470ca0de69 serial: earlycon: Enable earlycon without command line param
Earlycon matching can only be triggered if 'earlycon=...' has been
specified on the kernel command line. To workaround this limitation
requires tight coupling between arches and specific serial drivers
in order to start an earlycon. Devicetree avoids this limitation
with a link table that contains the required data to match earlycons.

Mirror this approach for earlycon match by name. Re-purpose
EARLYCON_DECLARE to generate a table entry which associates name with
setup() function. Re-purpose setup_earlycon() to scan this table for
an earlycon match, which is registered if found.

Declare one "earlycon" early_param, which calls setup_earlycon().

This design allows setup_earlycon() to be called directly with a
param string (as if 'earlycon=...' had been set on the command line).
Re-registration (either directly or by early_param) is prevented.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26 17:25:27 +01:00
Peter Hurley 7c53cb3de4 serial: earlycon: Refactor earlycon registration
Separate earlycon matching from registration; add register_earlycon
which initializes and registers the matched earlycon.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26 17:25:27 +01:00
Peter Hurley 6084688038 serial: earlycon: Skip parse_options() if empty string
Earlycon param strings of the form
   earlycon=<name>
are rejected from parse_options() with an error (which, in turn,
results in a NULL argument for the setup() method options parameter).

Only pass non-empty string to parse_options(); this will enable
handling actual parse errors differently than expected and allow
formats.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26 17:25:27 +01:00
Peter Hurley 526ebc3f56 serial: earlycon: Ignore parse_options() error code
Because setup_earlycon() continues to attempt console registration
if an error occurred parsing the option string, the actual value of
the error code from parse_options() is ignored.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26 16:17:56 +01:00
Peter Hurley feed5bab0d serial: earlycon: Move ->uartclk initialize
Initializing the ->uartclk field is not related to option parsing;
relocate from parse_options() to setup_earlycon() (which mirrors the
behavior of of_setup_earlycon()).

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26 16:17:55 +01:00
Peter Hurley 73abaf87f0 serial: earlycon: Refactor parse_options into serial core
Prepare to support console-defined matching; refactor the command
line parameter string processing from parse_options() into a
new core function, uart_parse_earlycon(), which decodes command line
parameters of the form:
   earlycon=<name>,io|mmio|mmio32,<addr>,<options>
   console=<name>,io|mmio|mmio32,<addr>,<options>
   earlycon=<name>,0x<addr>,<options>
   console=<name>,0x<addr>,<options>

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07 03:55:07 +01:00
Kumar Gala fe655de171 tty/serial: earlycon: Fix print for implied MMIO case
For the case in which we just provide an address as an argument to the
earlycon console type like:

earlycon=msm_serial_dm,0xf991e000

We would report this as an IO port based mapping and not as MMIO.  Simple
fix to use the port->iotype to decide which message to print.

Signed-off-by: Kumar Gala <galak@codeaurora.org>
Acked-by: Mark RUtland <mark.rutland@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 19:45:52 -08:00
Rob Herring 60efcf0414 tty/serial: fix 8250 early console option passing to regular console
In the conversion to generic early console, the passing of options from
the early 8250 console to the regular ttyS console was broken. This
resulted in the baud rate changing when switching consoles during boot.

This feature allows specifying a single console option on the kernel
command line rather than both an early console and regular serial tty
console. It would be nice to generalize this feature. However, it only
works if the correct baud rate can be probed early which is not the
case on many platforms which have non-standard UART clock rates. So for
now, this is left as an 8250 specific feature.

Reported-and-tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-19 13:07:26 -07:00
Rob Herring b0b6abd34c serial: earlycon: add DT support
This adds the infrastructure to generic earlycon for earlycon setup
using DT. The actual setup is not enabled until a following commit to
add the FDT parsing.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Grant Likely <grant.likely@linaro.org>
2014-05-20 15:19:25 -05:00
Rob Herring e26f1db9b8 tty/serial: fix generic earlycon option parsing
Commit 9aac588759 (tty/serial: add generic serial earlycon) moved
console option parsing from 8250_early.c and converted to kstrto*
functions from simple_strtoul along the way. However, kstrto* functions
are not equivalent in that they do not allow non-convertible characters
at the end such as "115200n8". Fix this by changing back to
simple_strtoul and ignore what checkpatch.pl says.

Reported-by: Yinghai Lu <yinghai@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-03 18:16:38 -04:00
Rob Herring 9aac588759 tty/serial: add generic serial earlycon
This introduces generic earlycon infrastructure for serial devices
based on the 8250 earlycon. This allows for supporting earlycon option
with other serial devices. The earlycon output is enabled at the time
early_params are processed.

Only architectures that have fixmap support or have functional ioremap
when early_params are processed are supported. This is the same
restriction that the 8250 driver had.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24 16:32:27 -07:00