multiboot.h

Go to the documentation of this file.

/*
 * Copyright (c) 2019 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */
 
#ifndef ZEPHYR_INCLUDE_ARCH_X86_MULTIBOOT_H_
#define ZEPHYR_INCLUDE_ARCH_X86_MULTIBOOT_H_
 
#ifndef _ASMLANGUAGE
 
/*
 * Multiboot (version 1) boot information structure.
 *
 * Only fields/values of interest to Zephyr are enumerated: at
 * present, that means only those pertaining to the framebuffer.
 */
 
struct multiboot_info {
        uint32_t flags;
        uint32_t mem_lower;
        uint32_t mem_upper;
        uint32_t unused0[8];
        uint32_t mmap_length;
        uint32_t mmap_addr;
        uint32_t unused1[9];
        uint32_t fb_addr_lo;
        uint32_t fb_addr_hi;
        uint32_t fb_pitch;
        uint32_t fb_width;
        uint32_t fb_height;
        uint8_t  fb_bpp;
        uint8_t  fb_type;
        uint8_t  fb_color_info[6];
};
 
extern struct multiboot_info multiboot_info;
 
extern void z_multiboot_init(struct multiboot_info *info_pa);
 
/*
 * the mmap_addr field points to a series of entries of the following form.
 */
 
struct multiboot_mmap {
        uint32_t size;
        uint64_t base;
        uint64_t length;
        uint32_t type;
} __packed;
 
#endif /* _ASMLANGUAGE */
 
/*
 * Possible values for multiboot_mmap.type field.
 * Other values should be assumed to be unusable ranges.
 */
 
#define MULTIBOOT_MMAP_RAM              1       /* available RAM */
#define MULTIBOOT_MMAP_ACPI             3       /* reserved for ACPI */
#define MULTIBOOT_MMAP_NVS              4       /* ACPI non-volatile */
#define MULTIBOOT_MMAP_DEFECTIVE        5       /* defective RAM module */
 
/*
 * Magic numbers: the kernel multiboot header (see crt0.S) begins with
 * MULTIBOOT_HEADER_MAGIC to signal to the booter that it supports
 * multiboot. On kernel entry, EAX is set to MULTIBOOT_EAX_MAGIC to
 * signal that the boot loader is multiboot compliant.
 */
 
#define MULTIBOOT_HEADER_MAGIC          0x1BADB002
#define MULTIBOOT_EAX_MAGIC             0x2BADB002
 
/*
 * Typically, we put no flags in the multiboot header, as it exists solely
 * to reassure the loader that we're a valid binary. The exception to this
 * is when we want the loader to configure the framebuffer for us.
 */
 
#define MULTIBOOT_HEADER_FLAG_MEM       BIT(1)  /* want mem_/mmap_* info */
#define MULTIBOOT_HEADER_FLAG_FB        BIT(2)  /* want fb_* info */
 
#ifdef CONFIG_MULTIBOOT_FRAMEBUF
#define MULTIBOOT_HEADER_FLAGS \
        (MULTIBOOT_HEADER_FLAG_FB | MULTIBOOT_HEADER_FLAG_MEM)
#else
#define MULTIBOOT_HEADER_FLAGS MULTIBOOT_HEADER_FLAG_MEM
#endif
 
/* The flags in the boot info structure tell us which fields are valid. */
 
#define MULTIBOOT_INFO_FLAGS_MEM        (1 << 0)        /* mem_* valid */
#define MULTIBOOT_INFO_FLAGS_MMAP       (1 << 6)        /* mmap_* valid */
#define MULTIBOOT_INFO_FLAGS_FB         (1 << 12)       /* fb_* valid */
 
/* The only fb_type we support is RGB. No text modes and no color palettes. */
 
#define MULTIBOOT_INFO_FB_TYPE_RGB      1
 
#endif /* ZEPHYR_INCLUDE_ARCH_X86_MULTIBOOT_H_ */