1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * Startup Code for RISC-V Core
5 * Copyright (c) 2017 Microsemi Corporation.
6 * Copyright (c) 2017 Padmarao Begari <Padmarao.Begari@microsemi.com>
8 * Copyright (C) 2017 Andes Technology Corporation
9 * Rick Chen, Andes Technology Corporation <rick@andestech.com>
12 #include <asm-offsets.h>
16 #include <asm/encoding.h>
22 #define RELOC_TYPE R_RISCV_32
29 #define RELOC_TYPE R_RISCV_64
30 #define SYM_INDEX 0x20
37 /* save hart id and dtb pointer */
42 csrw MODE_PREFIX(tvec), t0
44 /* mask all interrupts */
45 csrw MODE_PREFIX(ie), zero
52 * Set stackpointer in internal/ex RAM to call board_init_f
56 li t1, CONFIG_SYS_INIT_SP_ADDR
57 and sp, t1, t0 /* force 16 byte alignment */
59 #ifdef CONFIG_DEBUG_UART
65 jal board_init_f_alloc_reserve
68 la t0, prior_stage_fdt_address
71 jal board_init_f_init_reserve
73 mv a0, zero /* a0 <-- boot_flags = 0 */
75 jr t5 /* jump to board_init_f() */
78 * void relocate_code (addr_sp, gd, addr_moni)
80 * This "function" does not return, instead it continues in RAM
81 * after relocating the monitor code.
86 mv s2, a0 /* save addr_sp */
87 mv s3, a1 /* save addr of gd */
88 mv s4, a2 /* save addr of destination */
96 sub t6, s4, t0 /* t6 <- relocation offset */
97 beq t0, s4, clear_bss /* skip relocation */
99 mv t1, s4 /* t1 <- scratch for copy_loop */
101 sub t3, t3, t0 /* t3 <- __bss_start_ofs */
102 add t2, t0, t3 /* t2 <- source end address */
106 addi t0, t0, REGBYTES
108 addi t1, t1, REGBYTES
109 blt t0, t2, copy_loop
112 * Update dynamic relocations after board_init_f
115 la t1, __rel_dyn_start
117 beq t1, t2, clear_bss
118 add t1, t1, t6 /* t1 <- rela_dyn_start in RAM */
119 add t2, t2, t6 /* t2 <- rela_dyn_end in RAM */
122 * skip first reserved entry: address, type, addend
127 LREG t5, -(REGBYTES*2)(t1) /* t5 <-- relocation info:type */
128 li t3, R_RISCV_RELATIVE /* reloc type R_RISCV_RELATIVE */
129 bne t5, t3, 8f /* skip non-RISCV_RELOC entries */
130 LREG t3, -(REGBYTES*3)(t1)
131 LREG t5, -(REGBYTES)(t1) /* t5 <-- addend */
132 add t5, t5, t6 /* t5 <-- location to fix up in RAM */
133 add t3, t3, t6 /* t3 <-- location to fix up in RAM */
136 addi t1, t1, (REGBYTES*3)
140 la t4, __dyn_sym_start
144 LREG t5, -(REGBYTES*2)(t1) /* t5 <-- relocation info:type */
145 srli t0, t5, SYM_INDEX /* t0 <--- sym table index */
146 andi t5, t5, 0xFF /* t5 <--- relocation type */
148 bne t5, t3, 10f /* skip non-addned entries */
150 LREG t3, -(REGBYTES*3)(t1)
154 LREG t5, REGBYTES(s5)
155 add t5, t5, t6 /* t5 <-- location to fix up in RAM */
156 add t3, t3, t6 /* t3 <-- location to fix up in RAM */
159 addi t1, t1, (REGBYTES*3)
167 csrw MODE_PREFIX(tvec), t0
170 la t0, __bss_start /* t0 <- rel __bss_start in FLASH */
171 add t0, t0, t6 /* t0 <- rel __bss_start in RAM */
172 la t1, __bss_end /* t1 <- rel __bss_end in FLASH */
173 add t1, t1, t6 /* t1 <- rel __bss_end in RAM */
174 beq t0, t1, call_board_init_r
177 SREG zero, 0(t0) /* clear loop... */
178 addi t0, t0, REGBYTES
182 * We are done. Do not return, instead branch to second part of board
183 * initialization, now running from RAM.
186 jal invalidate_icache_all
189 mv t4, t0 /* offset of board_init_r() */
190 add t4, t4, t6 /* real address of board_init_r() */
192 * setup parameters for board_init_r
195 mv a1, s4 /* dest_addr */
200 jr t4 /* jump to board_init_r() */