LXR linux/drivers/firmware/google/coreboot

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * coreboot_table.h
   4 *
   5 * Internal header for coreboot table access.
   6 *
   7 * Copyright 2014 Gerd Hoffmann <kraxel@redhat.com>
   8 * Copyright 2017 Google Inc.
   9 * Copyright 2017 Samuel Holland <samuel@sholland.org>
  10 */
  11
  12#ifndef __COREBOOT_TABLE_H
  13#define __COREBOOT_TABLE_H
  14
  15#include <linux/device.h>
  16
  17/* Coreboot table header structure */
  18struct coreboot_table_header {
  19        char signature[4];
  20        u32 header_bytes;
  21        u32 header_checksum;
  22        u32 table_bytes;
  23        u32 table_checksum;
  24        u32 table_entries;
  25};
  26
  27/* List of coreboot entry structures that is used */
  28/* Generic */
  29struct coreboot_table_entry {
  30        u32 tag;
  31        u32 size;
  32};
  33
  34/* Points to a CBMEM entry */
  35struct lb_cbmem_ref {
  36        u32 tag;
  37        u32 size;
  38
  39        u64 cbmem_addr;
  40};
  41
  42/* Describes framebuffer setup by coreboot */
  43struct lb_framebuffer {
  44        u32 tag;
  45        u32 size;
  46
  47        u64 physical_address;
  48        u32 x_resolution;
  49        u32 y_resolution;
  50        u32 bytes_per_line;
  51        u8  bits_per_pixel;
  52        u8  red_mask_pos;
  53        u8  red_mask_size;
  54        u8  green_mask_pos;
  55        u8  green_mask_size;
  56        u8  blue_mask_pos;
  57        u8  blue_mask_size;
  58        u8  reserved_mask_pos;
  59        u8  reserved_mask_size;
  60};
  61
  62/* A device, additionally with information from coreboot. */
  63struct coreboot_device {
  64        struct device dev;
  65        union {
  66                struct coreboot_table_entry entry;
  67                struct lb_cbmem_ref cbmem_ref;
  68                struct lb_framebuffer framebuffer;
  69        };
  70};
  71
  72/* A driver for handling devices described in coreboot tables. */
  73struct coreboot_driver {
  74        int (*probe)(struct coreboot_device *);
  75        void (*remove)(struct coreboot_device *);
  76        struct device_driver drv;
  77        u32 tag;
  78};
  79
  80/* Register a driver that uses the data from a coreboot table. */
  81int coreboot_driver_register(struct coreboot_driver *driver);
  82
  83/* Unregister a driver that uses the data from a coreboot table. */
  84void coreboot_driver_unregister(struct coreboot_driver *driver);
  85
  86/* module_coreboot_driver() - Helper macro for drivers that don't do
  87 * anything special in module init/exit.  This eliminates a lot of
  88 * boilerplate.  Each module may only use this macro once, and
  89 * calling it replaces module_init() and module_exit()
  90 */
  91#define module_coreboot_driver(__coreboot_driver) \
  92        module_driver(__coreboot_driver, coreboot_driver_register, \
  93                        coreboot_driver_unregister)
  94
  95#endif /* __COREBOOT_TABLE_H */
  96