xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86, earlyprintk: Add earlyprintk for Intel Moorestown platform

Browse Source 
Intel Moorestown platform has a spi-uart device(Maxim3110),
which connects to a Designware spi core controller. This patch
will add early console function based on it.

As it will be used long before Linux spi subsystem get
initialised, we simply directly manipulate the spi controller's
register to acheive the early console func. This is safe as it
will be disabled when devices subsytem get initialised.

To use it, user need enable CONFIG_X86_MRST_EARLY_PRINTK in
kenrel config and add "earlyprintk=mrst" in kernel command line.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Cc: greg@kroah.com
LKML-Reference: <1284361736-23011-4-git-send-email-feng.tang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Feng Tang
2010-09-13 15:08:55 +08:00
committed by Ingo Molnar
parent 5a47c7dae8
commit c20b5c3318
5 changed files with 249 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
arch/x86/kernel/early_printk.c
View File

@@ -14,6 +14,7 @@
#include <xen/hvc-console.h>
#include <asm/pci-direct.h>
#include <asm/fixmap.h>
#include <asm/mrst.h>
#include <asm/pgtable.h>
#include <linux/usb/ehci_def.h>
@@ -238,6 +239,12 @@ static int __init setup_early_printk(char *buf)
#ifdef CONFIG_HVC_XEN
if (!strncmp(buf, "xen", 3))
early_console_register(&xenboot_console, keep);
#endif
#ifdef CONFIG_X86_MRST_EARLY_PRINTK
if (!strncmp(buf, "mrst", 4)) {
mrst_early_console_init();
early_console_register(&early_mrst_console, keep);
}
#endif
buf++;
}