x86/EFI: retrieve EDID

When booting directly from EFI, obtaining this information from EFI is
the only possible way. And even when booting with a boot loader
interposed, it's more clean not to use legacy BIOS calls for this
purpose. (The downside being that there are no "capabilities" that we
can retrieve the EFI way.)

To achieve this we need to propagate the handle used to obtain the
EFI_GRAPHICS_OUTPUT_PROTOCOL instance for further obtaining an
EFI_EDID_*_PROTOCOL instance, which has been part of the spec since 2.5.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com> # Arm, common
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Bertrand Marquis <bertrand.marquis@arm.com> #arm

diff --git a/xen/arch/arm/efi/efi-boot.h b/xen/arch/arm/efi/efi-boot.h
index ae8627134e5a4ee1614c331203c969ae063bf5cf..e452b687d8beee01cbd3bc2378c66b72ef15a70a 100644 (file)
--- a/xen/arch/arm/efi/efi-boot.h
+++ b/xen/arch/arm/efi/efi-boot.h
@@ -464,6 +464,10 @@ static void __init efi_arch_edd(void)
 {
 }
 
+static void __init efi_arch_edid(EFI_HANDLE gop_handle)
+{
+}
+
 static void __init efi_arch_memory_setup(void)
 {
 }

diff --git a/xen/arch/x86/boot/video.S b/xen/arch/x86/boot/video.S
index 0efbe8d3b33e878c370bbed1b3b679875ef2aa4d..22bc3732a0c2b8b42af09e6c6eca57a7e19119f5 100644 (file)
--- a/xen/arch/x86/boot/video.S
+++ b/xen/arch/x86/boot/video.S
@@ -890,7 +890,14 @@ store_edid:
         pushw   %dx
         pushw   %di
 
-        cmpb    $1, bootsym(opt_edid)   # EDID disabled on cmdline (edid=no)?
+        movb    bootsym(opt_edid), %al
+        cmpw    $0x1313, bootsym(boot_edid_caps) # Data already retrieved?
+        je      .Lcheck_edid
+        cmpb    $2, %al                 # EDID forced on cmdline (edid=force)?
+        jne     .Lno_edid
+
+.Lcheck_edid:
+        cmpb    $1, %al                 # EDID disabled on cmdline (edid=no)?
         je      .Lno_edid
 
         leaw    vesa_glob_info, %di

diff --git a/xen/arch/x86/efi/efi-boot.h b/xen/arch/x86/efi/efi-boot.h
index d91eb5a537f78f8e543985aeb3608b2f17e91fc7..6e65b569b0fa72809d7b1f78888f01018fbf62a2 100644 (file)
--- a/xen/arch/x86/efi/efi-boot.h
+++ b/xen/arch/x86/efi/efi-boot.h
@@ -568,6 +568,57 @@ static void __init efi_arch_video_init(EFI_GRAPHICS_OUTPUT_PROTOCOL *gop,
 #endif
 }
 
+#ifdef CONFIG_VIDEO
+static bool __init copy_edid(const void *buf, unsigned int size)
+{
+    /*
+     * Be conservative - for both undersized and oversized blobs it is unclear
+     * what to actually do with them. The more that unlike the VESA BIOS
+     * interface we also have no associated "capabilities" value (which might
+     * carry a hint as to possible interpretation).
+     */
+    if ( size != ARRAY_SIZE(boot_edid_info) )
+        return false;
+
+    memcpy(boot_edid_info, buf, size);
+    boot_edid_caps = 0;
+
+    return true;
+}
+#endif
+
+static void __init efi_arch_edid(EFI_HANDLE gop_handle)
+{
+#ifdef CONFIG_VIDEO
+    static EFI_GUID __initdata active_guid = EFI_EDID_ACTIVE_PROTOCOL_GUID;
+    static EFI_GUID __initdata discovered_guid = EFI_EDID_DISCOVERED_PROTOCOL_GUID;
+    EFI_EDID_ACTIVE_PROTOCOL *active_edid;
+    EFI_EDID_DISCOVERED_PROTOCOL *discovered_edid;
+    EFI_STATUS status;
+
+    status = efi_bs->OpenProtocol(gop_handle, &active_guid,
+                                  (void **)&active_edid, efi_ih, NULL,
+                                  EFI_OPEN_PROTOCOL_GET_PROTOCOL);
+    if ( status == EFI_SUCCESS &&
+         copy_edid(active_edid->Edid, active_edid->SizeOfEdid) )
+        return;
+
+    /*
+     * In case an override is in place which doesn't fit copy_edid(), also try
+     * obtaining the discovered EDID in the hope that it's better than nothing.
+     *
+     * Note that attempting to use the information in
+     * EFI_EDID_DISCOVERED_PROTOCOL when there's an override provided by
+     * EFI_EDID_ACTIVE_PROTOCOL might lead to issues.
+     */
+    status = efi_bs->OpenProtocol(gop_handle, &discovered_guid,
+                                  (void **)&discovered_edid, efi_ih, NULL,
+                                  EFI_OPEN_PROTOCOL_GET_PROTOCOL);
+    if ( status == EFI_SUCCESS )
+        copy_edid(discovered_edid->Edid, discovered_edid->SizeOfEdid);
+#endif
+}
+
 static void __init efi_arch_memory_setup(void)
 {
     unsigned int i;
@@ -729,6 +780,7 @@ static void __init efi_arch_flush_dcache_area(const void *vaddr, UINTN size) { }
 void __init efi_multiboot2(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
 {
     EFI_GRAPHICS_OUTPUT_PROTOCOL *gop;
+    EFI_HANDLE gop_handle;
     UINTN cols, gop_mode = ~0, rows;
 
     __set_bit(EFI_BOOT, &efi_flags);
@@ -742,11 +794,15 @@ void __init efi_multiboot2(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable
                            &cols, &rows) == EFI_SUCCESS )
         efi_arch_console_init(cols, rows);
 
-    gop = efi_get_gop();
+    gop = efi_get_gop(&gop_handle);
 
     if ( gop )
+    {
         gop_mode = efi_find_gop_mode(gop, 0, 0, 0);
 
+        efi_arch_edid(gop_handle);
+    }
+
     efi_arch_edd();
     efi_arch_cpu();
 

diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c
index 4dd5ea6a060257f8c7bf573ae46277a3f23e2be2..f827a72e93a6431e6282b4a8dad9e4d26f33319d 100644 (file)
--- a/xen/common/efi/boot.c
+++ b/xen/common/efi/boot.c
@@ -118,7 +118,7 @@ static bool read_section(const EFI_LOADED_IMAGE *image, const CHAR16 *name,
 
 static void efi_init(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable);
 static void efi_console_set_mode(void);
-static EFI_GRAPHICS_OUTPUT_PROTOCOL *efi_get_gop(void);
+static EFI_GRAPHICS_OUTPUT_PROTOCOL *efi_get_gop(EFI_HANDLE *gop_handle);
 static UINTN efi_find_gop_mode(EFI_GRAPHICS_OUTPUT_PROTOCOL *gop,
                                UINTN cols, UINTN rows, UINTN depth);
 static void efi_tables(void);
@@ -758,7 +758,7 @@ static void __init efi_console_set_mode(void)
         StdOut->SetMode(StdOut, best);
 }
 
-static EFI_GRAPHICS_OUTPUT_PROTOCOL __init *efi_get_gop(void)
+static EFI_GRAPHICS_OUTPUT_PROTOCOL __init *efi_get_gop(EFI_HANDLE *gop_handle)
 {
     EFI_GRAPHICS_OUTPUT_MODE_INFORMATION *mode_info;
     EFI_GRAPHICS_OUTPUT_PROTOCOL *gop = NULL;
@@ -783,7 +783,10 @@ static EFI_GRAPHICS_OUTPUT_PROTOCOL __init *efi_get_gop(void)
             continue;
         status = gop->QueryMode(gop, gop->Mode->Mode, &info_size, &mode_info);
         if ( !EFI_ERROR(status) )
+        {
+            *gop_handle = handles[i];
             break;
+        }
     }
     if ( handles )
         efi_bs->FreePool(handles);
@@ -1222,6 +1225,7 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
     if ( use_cfg_file )
     {
         EFI_FILE_HANDLE dir_handle;
+        EFI_HANDLE gop_handle;
         UINTN depth, cols, rows, size;
 
         size = cols = rows = depth = 0;
@@ -1230,7 +1234,7 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
                                &cols, &rows) == EFI_SUCCESS )
             efi_arch_console_init(cols, rows);
 
-        gop = efi_get_gop();
+        gop = efi_get_gop(&gop_handle);
 
         /* Get the file system interface. */
         dir_handle = get_parent_handle(loaded_image, &file_name);
@@ -1360,7 +1364,11 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
         dir_handle->Close(dir_handle);
 
         if ( gop && !base_video )
+        {
             gop_mode = efi_find_gop_mode(gop, cols, rows, depth);
+
+            efi_arch_edid(gop_handle);
+        }
     }
 
     /* Get the number of boot modules specified on the DT or an error (<0) */
@@ -1387,7 +1395,6 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
 
     efi_arch_edd();
 
-    /* XXX Collect EDID info. */
     efi_arch_cpu();
 
     efi_tables();

diff --git a/xen/include/efi/efiprot.h b/xen/include/efi/efiprot.h
index 8cf04df43721ddc64eb73f14f659686b724c658d..56d7636b2ba310e9f7ad0bdc96ce4877cc112e42 100644 (file)
--- a/xen/include/efi/efiprot.h
+++ b/xen/include/efi/efiprot.h
@@ -724,5 +724,52 @@ struct _EFI_GRAPHICS_OUTPUT_PROTOCOL {
   EFI_GRAPHICS_OUTPUT_PROTOCOL_BLT         Blt;
   EFI_GRAPHICS_OUTPUT_PROTOCOL_MODE        *Mode;
 };
+
+/*
+ * EFI EDID Discovered Protocol
+ * UEFI Specification Version 2.5 Section 11.9
+ */
+#define EFI_EDID_DISCOVERED_PROTOCOL_GUID \
+    { 0x1C0C34F6, 0xD380, 0x41FA, { 0xA0, 0x49, 0x8a, 0xD0, 0x6C, 0x1A, 0x66, 0xAA} }
+
+typedef struct _EFI_EDID_DISCOVERED_PROTOCOL {
+    UINT32   SizeOfEdid;
+    UINT8   *Edid;
+} EFI_EDID_DISCOVERED_PROTOCOL;
+
+/*
+ * EFI EDID Active Protocol
+ * UEFI Specification Version 2.5 Section 11.9
+ */
+#define EFI_EDID_ACTIVE_PROTOCOL_GUID \
+    { 0xBD8C1056, 0x9F36, 0x44EC, { 0x92, 0xA8, 0xA6, 0x33, 0x7F, 0x81, 0x79, 0x86} }
+
+typedef struct _EFI_EDID_ACTIVE_PROTOCOL {
+    UINT32   SizeOfEdid;
+    UINT8   *Edid;
+} EFI_EDID_ACTIVE_PROTOCOL;
+
+/*
+ * EFI EDID Override Protocol
+ * UEFI Specification Version 2.5 Section 11.9
+ */
+#define EFI_EDID_OVERRIDE_PROTOCOL_GUID \
+    { 0x48ECB431, 0xFB72, 0x45C0, { 0xA9, 0x22, 0xF4, 0x58, 0xFE, 0x04, 0x0B, 0xD5} }
+
+INTERFACE_DECL(_EFI_EDID_OVERRIDE_PROTOCOL);
+
+typedef
+EFI_STATUS
+(EFIAPI *EFI_EDID_OVERRIDE_PROTOCOL_GET_EDID) (
+  IN      struct _EFI_EDID_OVERRIDE_PROTOCOL   *This,
+  IN      EFI_HANDLE                           *ChildHandle,
+  OUT     UINT32                               *Attributes,
+  IN OUT  UINTN                                *EdidSize,
+  IN OUT  UINT8                               **Edid);
+
+typedef struct _EFI_EDID_OVERRIDE_PROTOCOL {
+    EFI_EDID_OVERRIDE_PROTOCOL_GET_EDID  GetEdid;
+} EFI_EDID_OVERRIDE_PROTOCOL;
+
 #endif