Files
opensbi/firmware/fw_base.S
Anup Patel 331f291e4c firmware: Relocate when load address is not equal to link address
This patch extends fw_base to relocate to link address whenever
firmware load address is not equal to link address.

The relocation will not work when load start to load end overlap
link start to link end.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
2019-06-12 17:56:28 +05:30

541 lines
12 KiB
ArmAsm

/*
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2019 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*/
#include <sbi/riscv_asm.h>
#include <sbi/riscv_encoding.h>
#include <sbi/sbi_platform.h>
#include <sbi/sbi_scratch.h>
#include <sbi/sbi_trap.h>
.macro MOV_3R __d0, __s0, __d1, __s1, __d2, __s2
add \__d0, \__s0, zero
add \__d1, \__s1, zero
add \__d2, \__s2, zero
.endm
.macro MOV_5R __d0, __s0, __d1, __s1, __d2, __s2, __d3, __s3, __d4, __s4
add \__d0, \__s0, zero
add \__d1, \__s1, zero
add \__d2, \__s2, zero
add \__d3, \__s3, zero
add \__d4, \__s4, zero
.endm
.align 3
.section .entry, "ax", %progbits
.globl _start
.globl _start_warm
_start:
/*
* Jump to warm-boot if this is not the first core booting,
* that is, for mhartid != 0
*/
csrr a6, CSR_MHARTID
blt zero, a6, _wait_for_boot_hart
/* Save load address */
la t0, _load_start
la t1, _start
REG_S t1, 0(t0)
/* Relocate if load address != link address */
la t0, _link_start
REG_L t0, 0(t0)
la t1, _link_end
REG_L t1, 0(t1)
la t2, _load_start
REG_L t2, 0(t2)
beq t0, t2, _relocate_done
la t4, _relocate_done
sub t4, t4, t2
add t4, t4, t0
_relocate_copy:
REG_L t3, 0(t2)
REG_S t3, 0(t0)
add t0, t0, __SIZEOF_POINTER__
add t2, t2, __SIZEOF_POINTER__
blt t0, t1, _relocate_copy
jr t4
_relocate_done:
/* At this point we are running from link address */
/* Reset all registers for boot HART */
li ra, 0
call _reset_regs
/* Allow main firmware to save info */
MOV_5R s0, a0, s1, a1, s2, a2, s3, a3, s4, a4
call fw_save_info
MOV_5R a0, s0, a1, s1, a2, s2, a3, s3, a4, s4
/* Preload HART details
* s7 -> HART Count
* s8 -> HART Stack Size
*/
la a4, platform
#if __riscv_xlen == 64
lwu s7, SBI_PLATFORM_HART_COUNT_OFFSET(a4)
lwu s8, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(a4)
#else
lw s7, SBI_PLATFORM_HART_COUNT_OFFSET(a4)
lw s8, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(a4)
#endif
/* Setup scratch space for all the HARTs*/
la tp, _fw_end
mul a5, s7, s8
add tp, tp, a5
/* Keep a copy of tp */
add t3, tp, zero
/* Counter */
li t2, 1
/* hartid 0 is mandated by ISA */
li t1, 0
_scratch_init:
add tp, t3, zero
mul a5, s8, t1
sub tp, tp, a5
li a5, SBI_SCRATCH_SIZE
sub tp, tp, a5
/* Initialize scratch space */
/* Store fw_start and fw_size in scratch space */
la a4, _fw_start
la a5, _fw_end
mul t0, s7, s8
add a5, a5, t0
sub a5, a5, a4
REG_S a4, SBI_SCRATCH_FW_START_OFFSET(tp)
REG_S a5, SBI_SCRATCH_FW_SIZE_OFFSET(tp)
/* Store next arg1 in scratch space */
MOV_3R s0, a0, s1, a1, s2, a2
call fw_next_arg1
REG_S a0, SBI_SCRATCH_NEXT_ARG1_OFFSET(tp)
MOV_3R a0, s0, a1, s1, a2, s2
/* Store next address in scratch space */
MOV_3R s0, a0, s1, a1, s2, a2
call fw_next_addr
REG_S a0, SBI_SCRATCH_NEXT_ADDR_OFFSET(tp)
MOV_3R a0, s0, a1, s1, a2, s2
/* Store next mode in scratch space */
MOV_3R s0, a0, s1, a1, s2, a2
call fw_next_mode
REG_S a0, SBI_SCRATCH_NEXT_MODE_OFFSET(tp)
MOV_3R a0, s0, a1, s1, a2, s2
/* Store warm_boot address in scratch space */
la a4, _start_warm
REG_S a4, SBI_SCRATCH_WARMBOOT_ADDR_OFFSET(tp)
/* Store platform address in scratch space */
la a4, platform
REG_S a4, SBI_SCRATCH_PLATFORM_ADDR_OFFSET(tp)
/* Store hartid-to-scratch function address in scratch space */
la a4, _hartid_to_scratch
REG_S a4, SBI_SCRATCH_HARTID_TO_SCRATCH_OFFSET(tp)
/* Clear tmp0 in scratch space */
REG_S zero, SBI_SCRATCH_TMP0_OFFSET(tp)
/* Store firmware options in scratch space */
MOV_3R s0, a0, s1, a1, s2, a2
#ifdef FW_OPTIONS
li a4, FW_OPTIONS
#else
add a4, zero, zero
#endif
call fw_options
or a4, a4, a0
REG_S a4, SBI_SCRATCH_OPTIONS_OFFSET(tp)
MOV_3R a0, s0, a1, s1, a2, s2
/* Move to next scratch space */
add t1, t1, t2
blt t1, s7, _scratch_init
/* Zero-out BSS */
la a4, _bss_start
la a5, _bss_end
_bss_zero:
REG_S zero, (a4)
add a4, a4, __SIZEOF_POINTER__
blt a4, a5, _bss_zero
/* Override pervious arg1 */
MOV_3R s0, a0, s1, a1, s2, a2
call fw_prev_arg1
add t1, a0, zero
MOV_3R a0, s0, a1, s1, a2, s2
beqz t1, _prev_arg1_override_done
add a1, t1, zero
_prev_arg1_override_done:
/*
* Relocate Flatened Device Tree (FDT)
* source FDT address = previous arg1
* destination FDT address = next arg1
*
* Note: We will preserve a0 and a1 passed by
* previous booting stage.
*/
beqz a1, _fdt_reloc_done
/* Mask values in a3 and a4 */
li a3, ~(__SIZEOF_POINTER__ - 1)
li a4, 0xff
/* t1 = destination FDT start address */
MOV_3R s0, a0, s1, a1, s2, a2
call fw_next_arg1
add t1, a0, zero
MOV_3R a0, s0, a1, s1, a2, s2
beqz t1, _fdt_reloc_done
beq t1, a1, _fdt_reloc_done
and t1, t1, a3
/* t0 = source FDT start address */
add t0, a1, zero
and t0, t0, a3
/* t2 = source FDT size in big-endian */
#if __riscv_xlen == 64
lwu t2, 4(t0)
#else
lw t2, 4(t0)
#endif
/* t3 = bit[15:8] of FDT size */
add t3, t2, zero
srli t3, t3, 16
and t3, t3, a4
slli t3, t3, 8
/* t4 = bit[23:16] of FDT size */
add t4, t2, zero
srli t4, t4, 8
and t4, t4, a4
slli t4, t4, 16
/* t5 = bit[31:24] of FDT size */
add t5, t2, zero
and t5, t5, a4
slli t5, t5, 24
/* t2 = bit[7:0] of FDT size */
srli t2, t2, 24
and t2, t2, a4
/* t2 = FDT size in little-endian */
or t2, t2, t3
or t2, t2, t4
or t2, t2, t5
/* t2 = destination FDT end address */
add t2, t1, t2
/* FDT copy loop */
ble t2, t1, _fdt_reloc_done
_fdt_reloc_again:
REG_L t3, 0(t0)
REG_S t3, 0(t1)
add t0, t0, __SIZEOF_POINTER__
add t1, t1, __SIZEOF_POINTER__
blt t1, t2, _fdt_reloc_again
_fdt_reloc_done:
/* Update boot hart flag */
la a4, _boot_hart_done
la a5, _start_warm
REG_S a5, (a4)
fence rw, rw
la t0, _link_start
REG_L t0, 0(t0)
sub a4, a4, t0
la t0, _load_start
REG_L t0, 0(t0)
add a4, a4, t0
REG_S a5, (a4)
fence rw, rw
j _start_warm
/* Wait for boot hart */
_wait_for_boot_hart:
la a4, _boot_hart_done
REG_L a5, 0(a4)
/* Reduce the bus traffic so that boot hart may proceed faster */
nop
nop
nop
beqz a5, _wait_for_boot_hart
jr a5
_start_warm:
/* Reset all registers for non-boot HARTs */
li ra, 0
call _reset_regs
/* Disable and clear all interrupts */
csrw CSR_MIE, zero
csrw CSR_MIP, zero
la a4, platform
#if __riscv_xlen == 64
lwu s7, SBI_PLATFORM_HART_COUNT_OFFSET(a4)
lwu s8, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(a4)
#else
lw s7, SBI_PLATFORM_HART_COUNT_OFFSET(a4)
lw s8, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(a4)
#endif
/* HART ID should be within expected limit */
csrr s6, CSR_MHARTID
bge s6, s7, _start_hang
/* find the scratch space for this hart */
la tp, _fw_end
mul a5, s7, s8
add tp, tp, a5
mul a5, s8, s6
sub tp, tp, a5
li a5, SBI_SCRATCH_SIZE
sub tp, tp, a5
/* update the mscratch */
csrw CSR_MSCRATCH, tp
/* Setup stack */
add sp, tp, zero
/* Setup trap handler */
la a4, _trap_handler
csrw CSR_MTVEC, a4
/* Make sure that mtvec is updated */
1: csrr a5, CSR_MTVEC
bne a4, a5, 1b
/* Initialize SBI runtime */
csrr a0, CSR_MSCRATCH
call sbi_init
/* We don't expect to reach here hence just hang */
j _start_hang
.align 3
_boot_hart_done:
RISCV_PTR 0
_load_start:
RISCV_PTR _fw_start
_link_start:
RISCV_PTR _fw_start
_link_end:
RISCV_PTR _fw_reloc_end
.align 3
.section .entry, "ax", %progbits
.globl _hartid_to_scratch
_hartid_to_scratch:
add sp, sp, -(3 * __SIZEOF_POINTER__)
REG_S s0, (sp)
REG_S s1, (__SIZEOF_POINTER__)(sp)
REG_S s2, (__SIZEOF_POINTER__ * 2)(sp)
/*
* a0 -> HART ID (passed by caller)
* s0 -> HART Stack Size
* s1 -> HART Stack End
* s2 -> Temporary
*/
la s2, platform
#if __riscv_xlen == 64
lwu s0, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(s2)
lwu s2, SBI_PLATFORM_HART_COUNT_OFFSET(s2)
#else
lw s0, SBI_PLATFORM_HART_STACK_SIZE_OFFSET(s2)
lw s2, SBI_PLATFORM_HART_COUNT_OFFSET(s2)
#endif
mul s2, s2, s0
la s1, _fw_end
add s1, s1, s2
mul s2, s0, a0
sub s1, s1, s2
li s2, SBI_SCRATCH_SIZE
sub a0, s1, s2
REG_L s0, (sp)
REG_L s1, (__SIZEOF_POINTER__)(sp)
REG_L s2, (__SIZEOF_POINTER__ * 2)(sp)
add sp, sp, (3 * __SIZEOF_POINTER__)
ret
.align 3
.section .entry, "ax", %progbits
.globl _start_hang
_start_hang:
wfi
j _start_hang
.align 3
.section .entry, "ax", %progbits
.globl _trap_handler
_trap_handler:
/* Swap TP and MSCRATCH */
csrrw tp, CSR_MSCRATCH, tp
/* Save T0 in scratch space */
REG_S t0, SBI_SCRATCH_TMP0_OFFSET(tp)
/* Check which mode we came from */
csrr t0, CSR_MSTATUS
srl t0, t0, MSTATUS_MPP_SHIFT
and t0, t0, PRV_M
xori t0, t0, PRV_M
beq t0, zero, _trap_handler_m_mode
/* We came from S-mode or U-mode */
_trap_handler_s_mode:
/* Set T0 to original SP */
add t0, sp, zero
/* Setup exception stack */
add sp, tp, -(SBI_TRAP_REGS_SIZE)
/* Jump to code common for all modes */
j _trap_handler_all_mode
/* We came from M-mode */
_trap_handler_m_mode:
/* Set T0 to original SP */
add t0, sp, zero
/* Re-use current SP as exception stack */
add sp, sp, -(SBI_TRAP_REGS_SIZE)
_trap_handler_all_mode:
/* Save original SP (from T0) on stack */
REG_S t0, SBI_TRAP_REGS_OFFSET(sp)(sp)
/* Restore T0 from scratch space */
REG_L t0, SBI_SCRATCH_TMP0_OFFSET(tp)
/* Save T0 on stack */
REG_S t0, SBI_TRAP_REGS_OFFSET(t0)(sp)
/* Swap TP and MSCRATCH */
csrrw tp, CSR_MSCRATCH, tp
/* Save MEPC and MSTATUS CSRs */
csrr t0, CSR_MEPC
REG_S t0, SBI_TRAP_REGS_OFFSET(mepc)(sp)
csrr t0, CSR_MSTATUS
REG_S t0, SBI_TRAP_REGS_OFFSET(mstatus)(sp)
/* Save all general regisers except SP and T0 */
REG_S zero, SBI_TRAP_REGS_OFFSET(zero)(sp)
REG_S ra, SBI_TRAP_REGS_OFFSET(ra)(sp)
REG_S gp, SBI_TRAP_REGS_OFFSET(gp)(sp)
REG_S tp, SBI_TRAP_REGS_OFFSET(tp)(sp)
REG_S t1, SBI_TRAP_REGS_OFFSET(t1)(sp)
REG_S t2, SBI_TRAP_REGS_OFFSET(t2)(sp)
REG_S s0, SBI_TRAP_REGS_OFFSET(s0)(sp)
REG_S s1, SBI_TRAP_REGS_OFFSET(s1)(sp)
REG_S a0, SBI_TRAP_REGS_OFFSET(a0)(sp)
REG_S a1, SBI_TRAP_REGS_OFFSET(a1)(sp)
REG_S a2, SBI_TRAP_REGS_OFFSET(a2)(sp)
REG_S a3, SBI_TRAP_REGS_OFFSET(a3)(sp)
REG_S a4, SBI_TRAP_REGS_OFFSET(a4)(sp)
REG_S a5, SBI_TRAP_REGS_OFFSET(a5)(sp)
REG_S a6, SBI_TRAP_REGS_OFFSET(a6)(sp)
REG_S a7, SBI_TRAP_REGS_OFFSET(a7)(sp)
REG_S s2, SBI_TRAP_REGS_OFFSET(s2)(sp)
REG_S s3, SBI_TRAP_REGS_OFFSET(s3)(sp)
REG_S s4, SBI_TRAP_REGS_OFFSET(s4)(sp)
REG_S s5, SBI_TRAP_REGS_OFFSET(s5)(sp)
REG_S s6, SBI_TRAP_REGS_OFFSET(s6)(sp)
REG_S s7, SBI_TRAP_REGS_OFFSET(s7)(sp)
REG_S s8, SBI_TRAP_REGS_OFFSET(s8)(sp)
REG_S s9, SBI_TRAP_REGS_OFFSET(s9)(sp)
REG_S s10, SBI_TRAP_REGS_OFFSET(s10)(sp)
REG_S s11, SBI_TRAP_REGS_OFFSET(s11)(sp)
REG_S t3, SBI_TRAP_REGS_OFFSET(t3)(sp)
REG_S t4, SBI_TRAP_REGS_OFFSET(t4)(sp)
REG_S t5, SBI_TRAP_REGS_OFFSET(t5)(sp)
REG_S t6, SBI_TRAP_REGS_OFFSET(t6)(sp)
/* Call C routine */
add a0, sp, zero
csrr a1, CSR_MSCRATCH
call sbi_trap_handler
/* Restore all general regisers except SP and T0 */
REG_L ra, SBI_TRAP_REGS_OFFSET(ra)(sp)
REG_L gp, SBI_TRAP_REGS_OFFSET(gp)(sp)
REG_L tp, SBI_TRAP_REGS_OFFSET(tp)(sp)
REG_L t1, SBI_TRAP_REGS_OFFSET(t1)(sp)
REG_L t2, SBI_TRAP_REGS_OFFSET(t2)(sp)
REG_L s0, SBI_TRAP_REGS_OFFSET(s0)(sp)
REG_L s1, SBI_TRAP_REGS_OFFSET(s1)(sp)
REG_L a0, SBI_TRAP_REGS_OFFSET(a0)(sp)
REG_L a1, SBI_TRAP_REGS_OFFSET(a1)(sp)
REG_L a2, SBI_TRAP_REGS_OFFSET(a2)(sp)
REG_L a3, SBI_TRAP_REGS_OFFSET(a3)(sp)
REG_L a4, SBI_TRAP_REGS_OFFSET(a4)(sp)
REG_L a5, SBI_TRAP_REGS_OFFSET(a5)(sp)
REG_L a6, SBI_TRAP_REGS_OFFSET(a6)(sp)
REG_L a7, SBI_TRAP_REGS_OFFSET(a7)(sp)
REG_L s2, SBI_TRAP_REGS_OFFSET(s2)(sp)
REG_L s3, SBI_TRAP_REGS_OFFSET(s3)(sp)
REG_L s4, SBI_TRAP_REGS_OFFSET(s4)(sp)
REG_L s5, SBI_TRAP_REGS_OFFSET(s5)(sp)
REG_L s6, SBI_TRAP_REGS_OFFSET(s6)(sp)
REG_L s7, SBI_TRAP_REGS_OFFSET(s7)(sp)
REG_L s8, SBI_TRAP_REGS_OFFSET(s8)(sp)
REG_L s9, SBI_TRAP_REGS_OFFSET(s9)(sp)
REG_L s10, SBI_TRAP_REGS_OFFSET(s10)(sp)
REG_L s11, SBI_TRAP_REGS_OFFSET(s11)(sp)
REG_L t3, SBI_TRAP_REGS_OFFSET(t3)(sp)
REG_L t4, SBI_TRAP_REGS_OFFSET(t4)(sp)
REG_L t5, SBI_TRAP_REGS_OFFSET(t5)(sp)
REG_L t6, SBI_TRAP_REGS_OFFSET(t6)(sp)
/* Restore MEPC and MSTATUS CSRs */
REG_L t0, SBI_TRAP_REGS_OFFSET(mepc)(sp)
csrw CSR_MEPC, t0
REG_L t0, SBI_TRAP_REGS_OFFSET(mstatus)(sp)
csrw CSR_MSTATUS, t0
/* Restore T0 */
REG_L t0, SBI_TRAP_REGS_OFFSET(t0)(sp)
/* Restore SP */
REG_L sp, SBI_TRAP_REGS_OFFSET(sp)(sp)
mret
.align 3
.section .entry, "ax", %progbits
.globl _reset_regs
_reset_regs:
/* flush the instruction cache */
fence.i
/* Reset all registers except ra, a0, a1 and a2 */
li sp, 0
li gp, 0
li tp, 0
li t0, 0
li t1, 0
li t2, 0
li s0, 0
li s1, 0
li a3, 0
li a4, 0
li a5, 0
li a6, 0
li a7, 0
li s2, 0
li s3, 0
li s4, 0
li s5, 0
li s6, 0
li s7, 0
li s8, 0
li s9, 0
li s10, 0
li s11, 0
li t3, 0
li t4, 0
li t5, 0
li t6, 0
csrw CSR_MSCRATCH, 0
ret