From 25472de89ee3b98cd466f69d1f419f943dcbcb0f Mon Sep 17 00:00:00 2001 From: Anup Patel <anup.patel@wdc.com> Date: Mon, 29 Apr 2019 10:44:15 +0530 Subject: firmware: Allow firmwares to provide next mode and options This patch extends existing firmwares (i.e. fw_jump and fw_payload) to explicitly provide next mode and options to fw_base. We also introduce fw_save_info() which is called by fw_base very early on boot HART. This function can be used by existing firmwares (i.e. fw_jump and fw_payload) to save information passed by previous booting stage. Overall, this is a preparatory patch for implementing fw_dynamic. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> --- firmware/fw_base.S | 67 +++++++++++++++++++++++++++++++++++++++------------ firmware/fw_jump.S | 50 +++++++++++++++++++++++++++++++++++--- firmware/fw_payload.S | 56 +++++++++++++++++++++++++++++++++++++----- 3 files changed, 148 insertions(+), 25 deletions(-) (limited to 'firmware') diff --git a/firmware/fw_base.S b/firmware/fw_base.S index 7897314..0d7cf69 100644 --- a/firmware/fw_base.S +++ b/firmware/fw_base.S @@ -13,6 +13,20 @@ #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 @@ -25,9 +39,15 @@ _start: csrr a6, CSR_MHARTID blt zero, a6, _wait_for_boot_hart + /* 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 @@ -59,6 +79,7 @@ _scratch_init: 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 @@ -66,27 +87,44 @@ _scratch_init: sub a5, a5, a4 REG_S a4, SBI_SCRATCH_FW_START_OFFSET(tp) REG_S a5, SBI_SCRATCH_FW_SIZE_OFFSET(tp) - /* Note: fw_next_arg1() uses a0, a1, and ra */ + /* 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) - /* Note: fw_next_addr() uses a0, a1, and ra */ + 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) - li a4, PRV_S - REG_S a4, SBI_SCRATCH_NEXT_MODE_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 - REG_S a4, SBI_SCRATCH_OPTIONS_OFFSET(tp) #else - REG_S zero, SBI_SCRATCH_OPTIONS_OFFSET(tp) + 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 @@ -99,12 +137,10 @@ _bss_zero: blt a4, a5, _bss_zero /* Override pervious arg1 */ - add s0, a0, zero - add s1, a1, zero + MOV_3R s0, a0, s1, a1, s2, a2 call fw_prev_arg1 add t1, a0, zero - add a0, s0, zero - add a1, s1, zero + MOV_3R a0, s0, a1, s1, a2, s2 beqz t1, _prev_arg1_override_done add a1, t1, zero _prev_arg1_override_done: @@ -122,13 +158,12 @@ _prev_arg1_override_done: li a3, ~(__SIZEOF_POINTER__ - 1) li a4, 0xff /* t1 = destination FDT start address */ - add s0, a0, zero - add s1, a1, zero + MOV_3R s0, a0, s1, a1, s2, a2 call fw_next_arg1 add t1, a0, zero - add a0, s0, zero - add a1, s1, 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 @@ -188,6 +223,7 @@ _wait_for_boot_hart: beqz a5, _wait_for_boot_hart _start_warm: + /* Reset all registers for non-boot HARTs */ li ra, 0 call _reset_regs @@ -430,7 +466,7 @@ _reset_regs: /* flush the instruction cache */ fence.i - /* Reset all registers except ra, a0,a1 */ + /* Reset all registers except ra, a0, a1 and a2 */ li sp, 0 li gp, 0 li tp, 0 @@ -439,7 +475,6 @@ _reset_regs: li t2, 0 li s0, 0 li s1, 0 - li a2, 0 li a3, 0 li a4, 0 li a5, 0 diff --git a/firmware/fw_jump.S b/firmware/fw_jump.S index 4b71863..cdf1f41 100644 --- a/firmware/fw_jump.S +++ b/firmware/fw_jump.S @@ -9,19 +9,37 @@ #include "fw_base.S" + .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: + 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: - /* We return previous arg1 in 'a0' */ 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: - /* We return next arg1 in 'a0' */ #ifdef FW_JUMP_FDT_ADDR li a0, FW_JUMP_FDT_ADDR #else @@ -32,12 +50,38 @@ fw_next_arg1: .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: - /* We return next address in 'a0' */ la a0, _jump_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: + li a0, PRV_S + 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: + add a0, zero, zero + ret + #ifndef FW_JUMP_ADDR #error "Must define FW_JUMP_ADDR" #endif diff --git a/firmware/fw_payload.S b/firmware/fw_payload.S index b86b63c..4b4527a 100644 --- a/firmware/fw_payload.S +++ b/firmware/fw_payload.S @@ -9,11 +9,26 @@ #include "fw_base.S" - .align 4 + .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: + 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: - /* We return previous arg1 in 'a0' */ #ifdef FW_PAYLOAD_FDT_PATH la a0, fdt_bin #else @@ -21,11 +36,14 @@ fw_prev_arg1: #endif ret - .align 4 + .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: - /* We return next arg1 in 'a0' */ #ifdef FW_PAYLOAD_FDT_ADDR li a0, FW_PAYLOAD_FDT_ADDR #else @@ -33,14 +51,40 @@ fw_next_arg1: #endif ret - .align 4 + .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: - /* We return next address in 'a0' */ la a0, payload_bin 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: + li a0, PRV_S + 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: + add a0, zero, zero + ret + #ifdef FW_PAYLOAD_FDT_PATH .align 4 .section .text, "ax", %progbits -- cgit v1.2.3