6 files changed, 33 insertions, 15 deletions

diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index e398bb5d63bb..8a84501acb1b 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -28,6 +28,9 @@ VMLINUX_OBJS = $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
         $(obj)/string.o $(obj)/cmdline.o $(obj)/early_serial_console.o \
         $(obj)/piggy.o
 
+$(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
+$(obj)/efi_stub_$(BITS).o: KBUILD_CLFAGS += -fshort-wchar -mno-red-zone
+
 ifeq ($(CONFIG_EFI_STUB), y)
         VMLINUX_OBJS += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o
 endif
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index b3e0227df2c9..c760e073963e 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -276,8 +276,9 @@ static efi_status_t setup_gop(struct screen_info *si, efi_guid_t *proto,
         nr_gops = size / sizeof(void *);
         for (i = 0; i < nr_gops; i++) {
                 struct efi_graphics_output_mode_info *info;
-                efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;
-                void *pciio;
+                efi_guid_t conout_proto = EFI_CONSOLE_OUT_DEVICE_GUID;
+                bool conout_found = false;
+                void *dummy;
                 void *h = gop_handle[i];
 
                 status = efi_call_phys3(sys_table->boottime->handle_protocol,
@@ -285,19 +286,21 @@ static efi_status_t setup_gop(struct screen_info *si, efi_guid_t *proto,
                 if (status != EFI_SUCCESS)
                         continue;
 
-                efi_call_phys3(sys_table->boottime->handle_protocol,
-                               h, &pciio_proto, &pciio);
+                status = efi_call_phys3(sys_table->boottime->handle_protocol,
+                                        h, &conout_proto, &dummy);
+
+                if (status == EFI_SUCCESS)
+                        conout_found = true;
 
                 status = efi_call_phys4(gop->query_mode, gop,
                                         gop->mode->mode, &size, &info);
-                if (status == EFI_SUCCESS && (!first_gop || pciio)) {
+                if (status == EFI_SUCCESS && (!first_gop || conout_found)) {
                         /*
-                         * Apple provide GOPs that are not backed by
-                         * real hardware (they're used to handle
-                         * multiple displays). The workaround is to
-                         * search for a GOP implementing the PCIIO
-                         * protocol, and if one isn't found, to just
-                         * fallback to the first GOP.
+                         * Systems that use the UEFI Console Splitter may
+                         * provide multiple GOP devices, not all of which are
+                         * backed by real hardware. The workaround is to search
+                         * for a GOP implementing the ConOut protocol, and if
+                         * one isn't found, to just fall back to the first GOP.
                          */
                         width = info->horizontal_resolution;
                         height = info->vertical_resolution;
@@ -308,10 +311,10 @@ static efi_status_t setup_gop(struct screen_info *si, efi_guid_t *proto,
                         pixels_per_scan_line = info->pixels_per_scan_line;
 
                         /*
-                         * Once we've found a GOP supporting PCIIO,
+                         * Once we've found a GOP supporting ConOut,
                          * don't bother looking any further.
                          */
-                        if (pciio)
+                        if (conout_found)
                                 break;
 
                         first_gop = gop;
@@ -328,7 +331,6 @@ static efi_status_t setup_gop(struct screen_info *si, efi_guid_t *proto,
         si->lfb_width = width;
         si->lfb_height = height;
         si->lfb_base = fb_base;
-        si->lfb_size = fb_size;
         si->pages = 1;
 
         if (pixel_format == PIXEL_RGB_RESERVED_8BIT_PER_COLOR) {
@@ -376,6 +378,10 @@ static efi_status_t setup_gop(struct screen_info *si, efi_guid_t *proto,
                 si->rsvd_pos = 0;
         }
 
+        si->lfb_size = si->lfb_linelength * si->lfb_height;
+
+        si->capabilities |= VIDEO_CAPABILITY_SKIP_QUIRKS;
+
 free_handle:
         efi_call_phys1(sys_table->boottime->free_pool, gop_handle);
         return status;
diff --git a/arch/x86/boot/compressed/eboot.h b/arch/x86/boot/compressed/eboot.h
index 3b6e15627c55..e5b0a8f91c5f 100644
--- a/arch/x86/boot/compressed/eboot.h
+++ b/arch/x86/boot/compressed/eboot.h
@@ -14,6 +14,10 @@
 #define EFI_PAGE_SIZE           (1UL << EFI_PAGE_SHIFT)
 #define EFI_READ_CHUNK_SIZE     (1024 * 1024)
 
+#define EFI_CONSOLE_OUT_DEVICE_GUID    \
+        EFI_GUID(0xd3b36f2c, 0xd551, 0x11d4, 0x9a, 0x46, 0x0, 0x90, 0x27, \
+                  0x3f, 0xc1, 0x4d)
+
 #define PIXEL_RGB_RESERVED_8BIT_PER_COLOR               0
 #define PIXEL_BGR_RESERVED_8BIT_PER_COLOR               1
 #define PIXEL_BIT_MASK                                  2
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 92660edaa1e7..f55a4ce6dc49 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -890,6 +890,7 @@ void __init efi_enter_virtual_mode(void)
          *
          * Call EFI services through wrapper functions.
          */
+        efi.runtime_version = efi_systab.fw_revision;
         efi.get_time = virt_efi_get_time;
         efi.set_time = virt_efi_set_time;
         efi.get_wakeup_time = virt_efi_get_wakeup_time;
diff --git a/drivers/video/efifb.c b/drivers/video/efifb.c
index b4a632ada401..932abaa58a89 100644
--- a/drivers/video/efifb.c
+++ b/drivers/video/efifb.c
@@ -553,7 +553,9 @@ static int __init efifb_init(void)
         int ret;
         char *option = NULL;
 
-        dmi_check_system(dmi_system_table);
+        if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI ||
+            !(screen_info.capabilities & VIDEO_CAPABILITY_SKIP_QUIRKS))
+                dmi_check_system(dmi_system_table);
 
         if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
                 return -ENODEV;
diff --git a/include/linux/screen_info.h b/include/linux/screen_info.h
index 899fbb487c94..fb3c5a8fef3d 100644
--- a/include/linux/screen_info.h
+++ b/include/linux/screen_info.h
@@ -68,6 +68,8 @@ struct screen_info {
 
 #define VIDEO_FLAGS_NOCURSOR    (1 << 0) /* The video mode has no cursor set */
 
+#define VIDEO_CAPABILITY_SKIP_QUIRKS    (1 << 0)
+
 #ifdef __KERNEL__
 extern struct screen_info screen_info;