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 #include <linux/mod_devicetable.h> 17 18 /* Coreboot table header structure */ 19 struct coreboot_table_header { 20 char signature[4]; 21 u32 header_bytes; 22 u32 header_checksum; 23 u32 table_bytes; 24 u32 table_checksum; 25 u32 table_entries; 26 }; 27 28 /* List of coreboot entry structures that is used */ 29 /* Generic */ 30 struct coreboot_table_entry { 31 u32 tag; 32 u32 size; 33 }; 34 35 /* Points to a CBMEM entry */ 36 struct lb_cbmem_ref { 37 u32 tag; 38 u32 size; 39 40 u64 cbmem_addr; 41 }; 42 43 #define LB_TAG_CBMEM_ENTRY 0x31 44 45 /* Corresponds to LB_TAG_CBMEM_ENTRY */ 46 struct lb_cbmem_entry { 47 u32 tag; 48 u32 size; 49 50 u64 address; 51 u32 entry_size; 52 u32 id; 53 }; 54 55 /* Describes framebuffer setup by coreboot */ 56 struct lb_framebuffer { 57 u32 tag; 58 u32 size; 59 60 u64 physical_address; 61 u32 x_resolution; 62 u32 y_resolution; 63 u32 bytes_per_line; 64 u8 bits_per_pixel; 65 u8 red_mask_pos; 66 u8 red_mask_size; 67 u8 green_mask_pos; 68 u8 green_mask_size; 69 u8 blue_mask_pos; 70 u8 blue_mask_size; 71 u8 reserved_mask_pos; 72 u8 reserved_mask_size; 73 }; 74 75 /* A device, additionally with information from coreboot. */ 76 struct coreboot_device { 77 struct device dev; 78 union { 79 struct coreboot_table_entry entry; 80 struct lb_cbmem_ref cbmem_ref; 81 struct lb_cbmem_entry cbmem_entry; 82 struct lb_framebuffer framebuffer; 83 DECLARE_FLEX_ARRAY(u8, raw); 84 }; 85 }; 86 87 static inline struct coreboot_device *dev_to_coreboot_device(struct device *dev) 88 { 89 return container_of(dev, struct coreboot_device, dev); 90 } 91 92 /* A driver for handling devices described in coreboot tables. */ 93 struct coreboot_driver { 94 int (*probe)(struct coreboot_device *); 95 void (*remove)(struct coreboot_device *); 96 struct device_driver drv; 97 const struct coreboot_device_id *id_table; 98 }; 99 100 /* use a macro to avoid include chaining to get THIS_MODULE */ 101 #define coreboot_driver_register(driver) \ 102 __coreboot_driver_register(driver, THIS_MODULE) 103 /* Register a driver that uses the data from a coreboot table. */ 104 int __coreboot_driver_register(struct coreboot_driver *driver, 105 struct module *owner); 106 107 /* Unregister a driver that uses the data from a coreboot table. */ 108 void coreboot_driver_unregister(struct coreboot_driver *driver); 109 110 /* module_coreboot_driver() - Helper macro for drivers that don't do 111 * anything special in module init/exit. This eliminates a lot of 112 * boilerplate. Each module may only use this macro once, and 113 * calling it replaces module_init() and module_exit() 114 */ 115 #define module_coreboot_driver(__coreboot_driver) \ 116 module_driver(__coreboot_driver, coreboot_driver_register, \ 117 coreboot_driver_unregister) 118 119 #endif /* __COREBOOT_TABLE_H */ 120