summaryrefslogtreecommitdiffstats
path: root/arch/x86/platform/efi/efi-bgrt.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/platform/efi/efi-bgrt.c')
-rw-r--r--arch/x86/platform/efi/efi-bgrt.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/arch/x86/platform/efi/efi-bgrt.c b/arch/x86/platform/efi/efi-bgrt.c
new file mode 100644
index 000000000000..f6a0c1b8e518
--- /dev/null
+++ b/arch/x86/platform/efi/efi-bgrt.c
@@ -0,0 +1,76 @@
+/*
+ * Copyright 2012 Intel Corporation
+ * Author: Josh Triplett <josh@joshtriplett.org>
+ *
+ * Based on the bgrt driver:
+ * Copyright 2012 Red Hat, Inc <mjg@redhat.com>
+ * Author: Matthew Garrett
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/acpi.h>
+#include <linux/efi.h>
+#include <linux/efi-bgrt.h>
+
+struct acpi_table_bgrt *bgrt_tab;
+void *bgrt_image;
+size_t bgrt_image_size;
+
+struct bmp_header {
+ u16 id;
+ u32 size;
+} __packed;
+
+void efi_bgrt_init(void)
+{
+ acpi_status status;
+ void __iomem *image;
+ bool ioremapped = false;
+ struct bmp_header bmp_header;
+
+ if (acpi_disabled)
+ return;
+
+ status = acpi_get_table("BGRT", 0,
+ (struct acpi_table_header **)&bgrt_tab);
+ if (ACPI_FAILURE(status))
+ return;
+
+ if (bgrt_tab->version != 1)
+ return;
+ if (bgrt_tab->image_type != 0 || !bgrt_tab->image_address)
+ return;
+
+ image = efi_lookup_mapped_addr(bgrt_tab->image_address);
+ if (!image) {
+ image = ioremap(bgrt_tab->image_address, sizeof(bmp_header));
+ ioremapped = true;
+ if (!image)
+ return;
+ }
+
+ memcpy_fromio(&bmp_header, image, sizeof(bmp_header));
+ if (ioremapped)
+ iounmap(image);
+ bgrt_image_size = bmp_header.size;
+
+ bgrt_image = kmalloc(bgrt_image_size, GFP_KERNEL);
+ if (!bgrt_image)
+ return;
+
+ if (ioremapped) {
+ image = ioremap(bgrt_tab->image_address, bmp_header.size);
+ if (!image) {
+ kfree(bgrt_image);
+ bgrt_image = NULL;
+ return;
+ }
+ }
+
+ memcpy_fromio(bgrt_image, image, bgrt_image_size);
+ if (ioremapped)
+ iounmap(image);
+}
OpenPOWER on IntegriCloud