diff options
| author | Anup Patel <anup.patel@wdc.com> | 2019-04-29 11:55:19 +0530 |
|---|---|---|
| committer | Anup Patel <anup@brainfault.org> | 2019-05-10 12:26:22 +0530 |
| commit | bae54f764570f3fa5c592f313b45352d9f6f1d8a (patch) | |
| tree | cca8ebe4dd67ceb9e4ffa5c1e32e6027241a41dc /firmware/fw_dynamic.S | |
| parent | 25472de89ee3b98cd466f69d1f419f943dcbcb0f (diff) | |
firmware: Add fw_dynamic firmware
This patch provides first-cut implementation of fw_dynamic firmware.
As compared to fw_jump and fw_payload, the fw_dynamic obtains next
address, next mode and OpenSBI options from struct fw_dynamic_info.
The previous booting stage can create struct fw_dynamic_info in memory
and pass address of struct fw_dynamic_info in 'a2' register. Also, the
struct fw_dynamic_info has versioning as well so changes to the struct
fw_dynamic_info can be done in a backward compatible manner.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Diffstat (limited to 'firmware/fw_dynamic.S')
| -rw-r--r-- | firmware/fw_dynamic.S | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/firmware/fw_dynamic.S b/firmware/fw_dynamic.S new file mode 100644 index 0000000..cf97b60 --- /dev/null +++ b/firmware/fw_dynamic.S @@ -0,0 +1,118 @@ +/* + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <sbi/fw_dynamic.h> + +#include "fw_base.S" + + .align 3 + .section .entry, "ax", %progbits +_bad_dynamic_info: + wfi + j _bad_dynamic_info + + .align 3 + .section .entry, "ax", %progbits + .global fw_save_info + /* + * We can only use a0, a1, a2, a3, and a4 registers here. + * The a0, a1, and a2 registers will be same as passed by + * previous booting stage. + * Nothing to be returned here. + */ +fw_save_info: + la a4, _dynamic_next_arg1 + REG_S a1, (a4) + li a4, FW_DYNAMIC_INFO_MAGIC_VALUE + REG_L a3, FW_DYNAMIC_INFO_MAGIC_OFFSET(a2) + bne a3, a4, _bad_dynamic_info + li a4, FW_DYNAMIC_INFO_VERSION_MAX + REG_L a3, FW_DYNAMIC_INFO_VERSION_OFFSET(a2) + bgt a3, a4, _bad_dynamic_info + la a4, _dynamic_next_addr + REG_L a3, FW_DYNAMIC_INFO_NEXT_ADDR_OFFSET(a2) + REG_S a3, (a4) + la a4, _dynamic_next_mode + REG_L a3, FW_DYNAMIC_INFO_NEXT_MODE_OFFSET(a2) + REG_S a3, (a4) + la a4, _dynamic_options + REG_L a3, FW_DYNAMIC_INFO_OPTIONS_OFFSET(a2) + REG_S a3, (a4) + ret + + .align 3 + .section .entry, "ax", %progbits + .global fw_prev_arg1 + /* + * We can only use a0, a1, and a2 registers here. + * The previous arg1 should be returned in 'a0'. + */ +fw_prev_arg1: + add a0, zero, zero + ret + + .align 3 + .section .entry, "ax", %progbits + .global fw_next_arg1 + /* + * We can only use a0, a1, and a2 registers here. + * The next arg1 should be returned in 'a0'. + */ +fw_next_arg1: + la a0, _dynamic_next_arg1 + REG_L a0, (a0) + ret + + .align 3 + .section .entry, "ax", %progbits + .global fw_next_addr + /* + * We can only use a0, a1, and a2 registers here. + * The next address should be returned in 'a0'. + */ +fw_next_addr: + la a0, _dynamic_next_addr + REG_L a0, (a0) + ret + + .align 3 + .section .entry, "ax", %progbits + .global fw_next_mode + /* + * We can only use a0, a1, and a2 registers here. + * The next address should be returned in 'a0' + */ +fw_next_mode: + la a0, _dynamic_next_mode + REG_L a0, (a0) + ret + + .align 3 + .section .entry, "ax", %progbits + .global fw_options + /* + * We can only use a0, a1, and a2 registers here. + * The 'a4' register will have default options. + * The next address should be returned in 'a0'. + */ +fw_options: + la a0, _dynamic_options + REG_L a0, (a0) + ret + + .align 3 + .section .entry, "ax", %progbits +_dynamic_next_arg1: + RISCV_PTR 0x0 +_dynamic_next_addr: + RISCV_PTR 0x0 +_dynamic_next_mode: + RISCV_PTR PRV_S +_dynamic_options: + RISCV_PTR 0x0 |