linux_dsm_epyc7002/include/linux/efi-bgrt.h
Josh Triplett 2223af3890 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>
2012-09-29 12:21:03 -07:00

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C

#ifndef _LINUX_EFI_BGRT_H
#define _LINUX_EFI_BGRT_H
#ifdef CONFIG_ACPI_BGRT
#include <linux/acpi.h>
void efi_bgrt_init(void);
/* The BGRT data itself; only valid if bgrt_image != NULL. */
extern void *bgrt_image;
extern size_t bgrt_image_size;
extern struct acpi_table_bgrt *bgrt_tab;
#else /* !CONFIG_ACPI_BGRT */
static inline void efi_bgrt_init(void) {}
#endif /* !CONFIG_ACPI_BGRT */
#endif /* _LINUX_EFI_BGRT_H */