libpayload: Cache copy of `cb_framebuffer` struct

Our AArch64 code supports dynamic framebuffer allocation which
makes it necessary to change the framebuffer information during
runtime. Having a pointer inside `libsysinfo` made a mess of it
as the pointer would either refer to the original struct inside
the coreboot table or to a new struct inside payload space. The
latter would be unaffected by a relocation of the payload.

Instead of the pointer, we'll always keep a copy of the whole
struct, which can be altered on demand without affecting the
coreboot table. To align the `video/graphics` driver with the
console driver, we also replace `fbaddr` with a macro `FB` that
calls phys_to_virt().

Change-Id: I3edc09cdb502a71516c1ee71457c1f8dcd01c119
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43578
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Julius Werner <jwerner@chromium.org>

1 files changed, 3 insertions, 6 deletions

diff --git a/payloads/libpayload/drivers/video/corebootfb.c b/payloads/libpayload/drivers/video/corebootfb.c
index c21665d0c0..1865ad37bf 100644
--- a/payloads/libpayload/drivers/video/corebootfb.c
+++ b/payloads/libpayload/drivers/video/corebootfb.c
@@ -60,7 +60,7 @@ static const u32 vga_colors[] = {
 	(0xFF << 16) | (0xFF << 8) | 0xFF,
 };
 
-struct cb_framebuffer fbinfo;
+static struct cb_framebuffer fbinfo;
 static unsigned short *chars;
 
 /* Shorthand for up-to-date virtual framebuffer address */
@@ -223,13 +223,10 @@ static void corebootfb_set_cursor(unsigned int x, unsigned int y)
 
 static int corebootfb_init(void)
 {
-	if (lib_sysinfo.framebuffer == NULL)
+	if (!lib_sysinfo.framebuffer.physical_address)
 		return -1;
 
-	fbinfo = *lib_sysinfo.framebuffer;
-
-	if (fbinfo.physical_address == 0)
-		return -1;
+	fbinfo = lib_sysinfo.framebuffer;
 
 	font_init(fbinfo.x_resolution);