u-boot/arch/arm/include/asm/arch-sunxi/spl.h
Andre Przywara 55d481d201 sunxi: Extend SPL header versioning
On Allwinner SoCs we use some free bytes at the beginning of the SPL image
to store various information. We have a version byte to allow updates,
but changing this always requires all tools to be updated as well.

Introduce the concept of semantic versioning [1] to the SPL header:
The major part of the version number only changes on incompatible
updates, a minor number bump indicates backward compatibility.
This patch just documents the major/minor split, adds some comments
to the header file and uses the versioning information for the existing
users.

[1] https://semver.org

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Acked-by: Jagan Teki <jagan@openedev.com>
2018-10-29 20:41:15 +05:30

87 lines
3.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* (C) Copyright 2007-2011
* Allwinner Technology Co., Ltd. <www.allwinnertech.com>
* Tom Cubie <tangliang@allwinnertech.com>
*/
#ifndef _ASM_ARCH_SPL_H_
#define _ASM_ARCH_SPL_H_
#define BOOT0_MAGIC "eGON.BT0"
#define SPL_SIGNATURE "SPL" /* marks "sunxi" SPL header */
#define SPL_MAJOR_BITS 3
#define SPL_MINOR_BITS 5
#define SPL_VERSION(maj, min) \
((((maj) & ((1U << SPL_MAJOR_BITS) - 1)) << SPL_MINOR_BITS) | \
((min) & ((1U << SPL_MINOR_BITS) - 1)))
#define SPL_HEADER_VERSION SPL_VERSION(0, 2)
#define SPL_ENV_HEADER_VERSION SPL_VERSION(0, 1)
#define SPL_DT_HEADER_VERSION SPL_VERSION(0, 2)
#define SPL_ADDR CONFIG_SUNXI_SRAM_ADDRESS
/* The low 8-bits of the 'boot_media' field in the SPL header */
#define SUNXI_BOOTED_FROM_MMC0 0
#define SUNXI_BOOTED_FROM_NAND 1
#define SUNXI_BOOTED_FROM_MMC2 2
#define SUNXI_BOOTED_FROM_SPI 3
/* boot head definition from sun4i boot code */
struct boot_file_head {
uint32_t b_instruction; /* one intruction jumping to real code */
uint8_t magic[8]; /* ="eGON.BT0" or "eGON.BT1", not C-style str */
uint32_t check_sum; /* generated by PC */
uint32_t length; /* generated by PC */
/*
* We use a simplified header, only filling in what is needed
* by the boot ROM. To be compatible with Allwinner tools we
* would need to implement the proper fields here instead of
* padding.
*
* Actually we want the ability to recognize our "sunxi" variant
* of the SPL. To do so, let's place a special signature into the
* "pub_head_size" field. We can reasonably expect Allwinner's
* boot0 to always have the upper 16 bits of this set to 0 (after
* all the value shouldn't be larger than the limit imposed by
* SRAM size).
* If the signature is present (at 0x14), then we know it's safe
* to use the remaining 8 bytes (at 0x18) for our own purposes.
* (E.g. sunxi-tools "fel" utility can pass information there.)
*/
union {
uint32_t pub_head_size;
uint8_t spl_signature[4];
};
uint32_t fel_script_address; /* since v0.1, set by sunxi-fel */
/*
* If the fel_uEnv_length member below is set to a non-zero value,
* it specifies the size (byte count) of data at fel_script_address.
* At the same time this indicates that the data is in uEnv.txt
* compatible format, ready to be imported via "env import -t".
*/
uint32_t fel_uEnv_length; /* since v0.1, set by sunxi-fel */
/*
* Offset of an ASCIIZ string (relative to the SPL header), which
* contains the default device tree name (CONFIG_DEFAULT_DEVICE_TREE).
* This is optional and may be set to NULL. Is intended to be used
* by flash programming tools for providing nice informative messages
* to the users.
*/
uint32_t dt_name_offset; /* since v0.2, set by mksunxiboot */
uint32_t reserved1;
uint32_t boot_media; /* written here by the boot ROM */
/* A padding area (may be used for storing text strings) */
uint32_t string_pool[13]; /* since v0.2, filled by mksunxiboot */
/* The header must be a multiple of 32 bytes (for VBAR alignment) */
};
/* Compile time check to assure proper alignment of structure */
typedef char boot_file_head_not_multiple_of_32[1 - 2*(sizeof(struct boot_file_head) % 32)];
#define is_boot0_magic(addr) (memcmp((void *)addr, BOOT0_MAGIC, 8) == 0)
uint32_t sunxi_get_boot_device(void);
#endif