path: root/init/main.c
diff options
authorMagnus Damm <damm@igel.co.jp>2009-03-30 14:37:25 -0700
committerGreg Kroah-Hartman <gregkh@suse.de>2009-04-16 16:17:10 -0700
commit13977091a988fb0d21821c2221ddc920eba36b79 (patch)
tree9e077f6d22e351c3bab494d49d954d5e30deaa1b /init/main.c
parentproc: mounts_poll() make consistent to mdstat_poll (diff)
Driver Core: early platform driver
V3 of the early platform driver implementation. Platform drivers are great for embedded platforms because we can separate driver configuration from the actual driver. So base addresses, interrupts and other configuration can be kept with the processor or board code, and the platform driver can be reused by many different platforms. For early devices we have nothing today. For instance, to configure early timers and early serial ports we cannot use platform devices. This because the setup order during boot. Timers are needed before the platform driver core code is available. The same goes for early printk support. Early in this case means before initcalls. These early drivers today have their configuration either hard coded or they receive it using some special configuration method. This is working quite well, but if we want to support both regular kernel modules and early devices then we need to have two ways of configuring the same driver. A single way would be better. The early platform driver patch is basically a set of functions that allow drivers to register themselves and architecture code to locate them and probe. Registration happens through early_param(). The time for the probe is decided by the architecture code. See Documentation/driver-model/platform.txt for more details. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Magnus Damm <damm@igel.co.jp> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: David Brownell <david-b@pacbell.net> Cc: Tejun Heo <htejun@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'init/main.c')
1 files changed, 6 insertions, 1 deletions
diff --git a/init/main.c b/init/main.c
index 3585f073d636..3bbf93be744c 100644
--- a/init/main.c
+++ b/init/main.c
@@ -492,6 +492,11 @@ static int __init do_early_param(char *param, char *val)
return 0;
+void __init parse_early_options(char *cmdline)
+ parse_args("early options", cmdline, NULL, 0, do_early_param);
/* Arch code calls this early on, or if not, just before other parsing. */
void __init parse_early_param(void)
@@ -503,7 +508,7 @@ void __init parse_early_param(void)
/* All fall through to do_early_param. */
strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
- parse_args("early options", tmp_cmdline, NULL, 0, do_early_param);
+ parse_early_options(tmp_cmdline);
done = 1;