x86_64 EFI boot support: EFI frame buffer driver

This patch adds Graphics Output Protocol support to the kernel.  UEFI2.0 spec
deprecates Universal Graphics Adapter (UGA) protocol and only Graphics Output
Protocol (GOP) is produced.  Therefore, the boot loader needs to query the
UEFI firmware with appropriate Output Protocol and pass the video information
to the kernel.  As a result of GOP protocol, an EFI framebuffer driver is
needed for displaying console messages.  The patch adds a EFI framebuffer
driver.  The EFI frame buffer driver in this patch is based on the Intel Mac
framebuffer driver.

The ELILO bootloader takes care of passing the video information as
appropriate for EFI firmware.

The framebuffer driver has been tested in i386 kernel and x86_64 kernel on EFI
platform.

Signed-off-by: Chandramouli Narayanan <mouli@linux.intel.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@suse.de>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/screen_info.h b/include/linux/screen_info.h
index 827b85bbf388..1ee2c05142f6 100644
--- a/include/linux/screen_info.h
+++ b/include/linux/screen_info.h
@@ -63,6 +63,8 @@ struct screen_info {
 
 #define VIDEO_TYPE_PMAC         0x60    /* PowerMacintosh frame buffer. */
 
+#define VIDEO_TYPE_EFI          0x70    /* EFI graphic mode             */
+
 #ifdef __KERNEL__
 extern struct screen_info screen_info;