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authorJosh Triplett <josh@joshtriplett.org>2012-09-28 17:57:05 -0700
committerH. Peter Anvin <hpa@linux.intel.com>2012-09-29 12:21:03 -0700
commit2223af389032425e3d1a70f9cb3a63feaa654ced (patch)
tree6874c07f26b3cdc5b10e06c34e7d0f6a9f5494aa /drivers/acpi
parent7bc90e01c3f66c137e7e761f574bbf883087d590 (diff)
downloadlinux-linaro-stable-2223af389032425e3d1a70f9cb3a63feaa654ced.tar.gz
efi: Fix the ACPI BGRT driver for images located in EFI boot services memory
The ACPI BGRT driver accesses the BIOS logo image when it initializes. However, ACPI 5.0 (which introduces the BGRT) recommends putting the logo image in EFI boot services memory, so that the OS can reclaim that memory. Production systems follow this recommendation, breaking the ACPI BGRT driver. Move the bulk of the BGRT code to run during a new EFI late initialization phase, which occurs after switching EFI to virtual mode, and after initializing ACPI, but before freeing boot services memory. Copy the BIOS logo image to kernel memory at that point, and make it accessible to the BGRT driver. Rework the existing ACPI BGRT driver to act as a simple wrapper exposing that image (and the properties from the BGRT) via sysfs. Signed-off-by: Josh Triplett <josh@joshtriplett.org> Link: http://lkml.kernel.org/r/93ce9f823f1c1f3bb88bdd662cce08eee7a17f5d.1348876882.git.josh@joshtriplett.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'drivers/acpi')
-rw-r--r--drivers/acpi/Kconfig4
-rw-r--r--drivers/acpi/bgrt.c76
2 files changed, 11 insertions, 69 deletions
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 80998958cf45..119d58db8342 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -385,8 +385,8 @@ config ACPI_CUSTOM_METHOD
to override that restriction).
config ACPI_BGRT
- tristate "Boottime Graphics Resource Table support"
- default n
+ bool "Boottime Graphics Resource Table support"
+ depends on EFI
help
This driver adds support for exposing the ACPI Boottime Graphics
Resource Table, which allows the operating system to obtain
diff --git a/drivers/acpi/bgrt.c b/drivers/acpi/bgrt.c
index 6680df36b963..be6039958545 100644
--- a/drivers/acpi/bgrt.c
+++ b/drivers/acpi/bgrt.c
@@ -1,5 +1,6 @@
/*
* Copyright 2012 Red Hat, Inc <mjg@redhat.com>
+ * Copyright 2012 Intel Corporation
*
* 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
@@ -11,20 +12,10 @@
#include <linux/init.h>
#include <linux/device.h>
#include <linux/sysfs.h>
-#include <linux/io.h>
-#include <acpi/acpi.h>
-#include <acpi/acpi_bus.h>
+#include <linux/efi-bgrt.h>
-static struct acpi_table_bgrt *bgrt_tab;
static struct kobject *bgrt_kobj;
-struct bmp_header {
- u16 id;
- u32 size;
-} __attribute ((packed));
-
-static struct bmp_header bmp_header;
-
static ssize_t show_version(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -63,18 +54,7 @@ static DEVICE_ATTR(yoffset, S_IRUGO, show_yoffset, NULL);
static ssize_t show_image(struct file *file, struct kobject *kobj,
struct bin_attribute *attr, char *buf, loff_t off, size_t count)
{
- int size = attr->size;
- void __iomem *image = attr->private;
-
- if (off >= size) {
- count = 0;
- } else {
- if (off + count > size)
- count = size - off;
-
- memcpy_fromio(buf, image+off, count);
- }
-
+ memcpy(buf, attr->private + off, count);
return count;
}
@@ -101,45 +81,18 @@ static struct attribute_group bgrt_attribute_group = {
static int __init bgrt_init(void)
{
- acpi_status status;
int ret;
- void __iomem *bgrt;
- if (acpi_disabled)
- return -ENODEV;
-
- status = acpi_get_table("BGRT", 0,
- (struct acpi_table_header **)&bgrt_tab);
-
- if (ACPI_FAILURE(status))
+ if (!bgrt_image)
return -ENODEV;
sysfs_bin_attr_init(&image_attr);
-
- bgrt = ioremap(bgrt_tab->image_address, sizeof(struct bmp_header));
-
- if (!bgrt) {
- ret = -EINVAL;
- goto out_err;
- }
-
- memcpy_fromio(&bmp_header, bgrt, sizeof(bmp_header));
- image_attr.size = bmp_header.size;
- iounmap(bgrt);
-
- image_attr.private = ioremap(bgrt_tab->image_address, image_attr.size);
-
- if (!image_attr.private) {
- ret = -EINVAL;
- goto out_err;
- }
-
+ image_attr.private = bgrt_image;
+ image_attr.size = bgrt_image_size;
bgrt_kobj = kobject_create_and_add("bgrt", acpi_kobj);
- if (!bgrt_kobj) {
- ret = -EINVAL;
- goto out_iounmap;
- }
+ if (!bgrt_kobj)
+ return -EINVAL;
ret = sysfs_create_group(bgrt_kobj, &bgrt_attribute_group);
if (ret)
@@ -155,22 +108,11 @@ out_group:
sysfs_remove_group(bgrt_kobj, &bgrt_attribute_group);
out_kobject:
kobject_put(bgrt_kobj);
-out_iounmap:
- iounmap(image_attr.private);
-out_err:
return ret;
}
-static void __exit bgrt_exit(void)
-{
- iounmap(image_attr.private);
- sysfs_remove_group(bgrt_kobj, &bgrt_attribute_group);
- sysfs_remove_bin_file(bgrt_kobj, &image_attr);
-}
-
module_init(bgrt_init);
-module_exit(bgrt_exit);
-MODULE_AUTHOR("Matthew Garrett");
+MODULE_AUTHOR("Matthew Garrett, Josh Triplett <josh@joshtriplett.org>");
MODULE_DESCRIPTION("BGRT boot graphic support");
MODULE_LICENSE("GPL");