From e8e39597a33cc53aacbaf4ef5cae60ed86d6a20a Mon Sep 17 00:00:00 2001 From: Rick Chen Date: Tue, 26 Dec 2017 13:55:48 +0800 Subject: riscv: cpu: Add nx25 to support RISC-V Add Andes nx25 cpu core (called AndesStar V5) to support RISC-V arch Verifications: 1. startup and relocation ok. 2. boot from rom or ram both ok. 2. timer driver ok. 3. uart driver ok 4. mmc driver ok 5. spi driver ok. 6. 32/64 bit both ok. Detail verification message please see doc/README.ae250. Signed-off-by: Rick Chen Signed-off-by: Rick Chen Signed-off-by: Greentime Hu Cc: Padmarao Begari --- arch/riscv/cpu/nx25/start.S | 291 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 291 insertions(+) create mode 100644 arch/riscv/cpu/nx25/start.S (limited to 'arch/riscv/cpu/nx25/start.S') diff --git a/arch/riscv/cpu/nx25/start.S b/arch/riscv/cpu/nx25/start.S new file mode 100644 index 0000000000..6a076639d3 --- /dev/null +++ b/arch/riscv/cpu/nx25/start.S @@ -0,0 +1,291 @@ +/* + * Startup Code for RISC-V Core + * + * Copyright (c) 2017 Microsemi Corporation. + * Copyright (c) 2017 Padmarao Begari + * + * Copyright (C) 2017 Andes Technology Corporation + * Rick Chen, Andes Technology Corporation + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include +#include +#include + +#ifdef CONFIG_32BIT +#define LREG lw +#define SREG sw +#define REGBYTES 4 +#define RELOC_TYPE R_RISCV_32 +#define SYM_INDEX 0x8 +#define SYM_SIZE 0x10 +#else +#define LREG ld +#define SREG sd +#define REGBYTES 8 +#define RELOC_TYPE R_RISCV_64 +#define SYM_INDEX 0x20 +#define SYM_SIZE 0x18 +#endif + +.section .text +.globl _start +_start: + j handle_reset + +nmi_vector: + j nmi_vector + +trap_vector: + j trap_entry + +.global trap_entry +handle_reset: + la t0, trap_entry + csrw mtvec, t0 + csrwi mstatus, 0 + csrwi mie, 0 + +/* + * Do CPU critical regs init only at reboot, + * not when booting from ram + */ +#ifdef CONFIG_INIT_CRITICAL + jal cpu_init_crit /* Do CPU critical regs init */ +#endif + +/* + * Set stackpointer in internal/ex RAM to call board_init_f + */ +call_board_init_f: + li t0, -16 + li t1, CONFIG_SYS_INIT_SP_ADDR + and sp, t1, t0 /* force 16 byte alignment */ + +#ifdef CONFIG_DEBUG_UART + jal debug_uart_init +#endif + +call_board_init_f_0: + mv a0, sp + jal board_init_f_alloc_reserve + mv sp, a0 + jal board_init_f_init_reserve + + mv a0, zero /* a0 <-- boot_flags = 0 */ + la t5, board_init_f + jr t5 /* jump to board_init_f() */ + +/* + * void relocate_code (addr_sp, gd, addr_moni) + * + * This "function" does not return, instead it continues in RAM + * after relocating the monitor code. + * + */ +.globl relocate_code +relocate_code: + mv s2, a0 /* save addr_sp */ + mv s3, a1 /* save addr of gd */ + mv s4, a2 /* save addr of destination */ + +/* + *Set up the stack + */ +stack_setup: + mv sp, s2 + la t0, _start + sub t6, s4, t0 /* t6 <- relocation offset */ + beq t0, s4, clear_bss /* skip relocation */ + + mv t1, s4 /* t1 <- scratch for copy_loop */ + la t3, __bss_start + sub t3, t3, t0 /* t3 <- __bss_start_ofs */ + add t2, t0, t3 /* t2 <- source end address */ + +copy_loop: + LREG t5, 0(t0) + addi t0, t0, REGBYTES + SREG t5, 0(t1) + addi t1, t1, REGBYTES + blt t0, t2, copy_loop + +/* + * Update dynamic relocations after board_init_f + */ +fix_rela_dyn: + la t1, __rel_dyn_start + la t2, __rel_dyn_end + beq t1, t2, clear_bss + add t1, t1, t6 /* t1 <- rela_dyn_start in RAM */ + add t2, t2, t6 /* t2 <- rela_dyn_end in RAM */ + +/* + * skip first reserved entry: address, type, addend + */ + bne t1, t2, 7f + +6: + LREG t5, -(REGBYTES*2)(t1) /* t5 <-- relocation info:type */ + li t3, R_RISCV_RELATIVE /* reloc type R_RISCV_RELATIVE */ + bne t5, t3, 8f /* skip non-RISCV_RELOC entries */ + LREG t3, -(REGBYTES*3)(t1) + LREG t5, -(REGBYTES)(t1) /* t5 <-- addend */ + add t5, t5, t6 /* t5 <-- location to fix up in RAM */ + add t3, t3, t6 /* t3 <-- location to fix up in RAM */ + SREG t5, 0(t3) +7: + addi t1, t1, (REGBYTES*3) + ble t1, t2, 6b + +8: + la t4, __dyn_sym_start + add t4, t4, t6 + +9: + LREG t5, -(REGBYTES*2)(t1) /* t5 <-- relocation info:type */ + srli t0, t5, SYM_INDEX /* t0 <--- sym table index */ + andi t5, t5, 0xFF /* t5 <--- relocation type */ + li t3, RELOC_TYPE + bne t5, t3, 10f /* skip non-addned entries */ + + LREG t3, -(REGBYTES*3)(t1) + li t5, SYM_SIZE + mul t0, t0, t5 + add s1, t4, t0 + LREG t5, REGBYTES(s1) + add t5, t5, t6 /* t5 <-- location to fix up in RAM */ + add t3, t3, t6 /* t3 <-- location to fix up in RAM */ + SREG t5, 0(t3) +10: + addi t1, t1, (REGBYTES*3) + ble t1, t2, 9b + +/* + * trap update +*/ + la t0, trap_entry + add t0, t0, t6 + csrw mtvec, t0 + +clear_bss: + la t0, __bss_start /* t0 <- rel __bss_start in FLASH */ + add t0, t0, t6 /* t0 <- rel __bss_start in RAM */ + la t1, __bss_end /* t1 <- rel __bss_end in FLASH */ + add t1, t1, t6 /* t1 <- rel __bss_end in RAM */ + li t2, 0x00000000 /* clear */ + beq t0, t1, call_board_init_r + +clbss_l: + SREG t2, 0(t0) /* clear loop... */ + addi t0, t0, REGBYTES + bne t0, t1, clbss_l + +/* + * We are done. Do not return, instead branch to second part of board + * initialization, now running from RAM. + */ +call_board_init_r: + la t0, board_init_r + mv t4, t0 /* offset of board_init_r() */ + add t4, t4, t6 /* real address of board_init_r() */ +/* + * setup parameters for board_init_r + */ + mv a0, s3 /* gd_t */ + mv a1, s4 /* dest_addr */ + +/* + * jump to it ... + */ + jr t4 /* jump to board_init_r() */ + +/* + * trap entry + */ +trap_entry: + addi sp, sp, -32*REGBYTES + SREG x1, 1*REGBYTES(sp) + SREG x2, 2*REGBYTES(sp) + SREG x3, 3*REGBYTES(sp) + SREG x4, 4*REGBYTES(sp) + SREG x5, 5*REGBYTES(sp) + SREG x6, 6*REGBYTES(sp) + SREG x7, 7*REGBYTES(sp) + SREG x8, 8*REGBYTES(sp) + SREG x9, 9*REGBYTES(sp) + SREG x10, 10*REGBYTES(sp) + SREG x11, 11*REGBYTES(sp) + SREG x12, 12*REGBYTES(sp) + SREG x13, 13*REGBYTES(sp) + SREG x14, 14*REGBYTES(sp) + SREG x15, 15*REGBYTES(sp) + SREG x16, 16*REGBYTES(sp) + SREG x17, 17*REGBYTES(sp) + SREG x18, 18*REGBYTES(sp) + SREG x19, 19*REGBYTES(sp) + SREG x20, 20*REGBYTES(sp) + SREG x21, 21*REGBYTES(sp) + SREG x22, 22*REGBYTES(sp) + SREG x23, 23*REGBYTES(sp) + SREG x24, 24*REGBYTES(sp) + SREG x25, 25*REGBYTES(sp) + SREG x26, 26*REGBYTES(sp) + SREG x27, 27*REGBYTES(sp) + SREG x28, 28*REGBYTES(sp) + SREG x29, 29*REGBYTES(sp) + SREG x30, 30*REGBYTES(sp) + SREG x31, 31*REGBYTES(sp) + csrr a0, mcause + csrr a1, mepc + mv a2, sp + jal handle_trap + csrw mepc, a0 + +/* + * Remain in M-mode after mret + */ + li t0, MSTATUS_MPP + csrs mstatus, t0 + LREG x1, 1*REGBYTES(sp) + LREG x2, 2*REGBYTES(sp) + LREG x3, 3*REGBYTES(sp) + LREG x4, 4*REGBYTES(sp) + LREG x5, 5*REGBYTES(sp) + LREG x6, 6*REGBYTES(sp) + LREG x7, 7*REGBYTES(sp) + LREG x8, 8*REGBYTES(sp) + LREG x9, 9*REGBYTES(sp) + LREG x10, 10*REGBYTES(sp) + LREG x11, 11*REGBYTES(sp) + LREG x12, 12*REGBYTES(sp) + LREG x13, 13*REGBYTES(sp) + LREG x14, 14*REGBYTES(sp) + LREG x15, 15*REGBYTES(sp) + LREG x16, 16*REGBYTES(sp) + LREG x17, 17*REGBYTES(sp) + LREG x18, 18*REGBYTES(sp) + LREG x19, 19*REGBYTES(sp) + LREG x20, 20*REGBYTES(sp) + LREG x21, 21*REGBYTES(sp) + LREG x22, 22*REGBYTES(sp) + LREG x23, 23*REGBYTES(sp) + LREG x24, 24*REGBYTES(sp) + LREG x25, 25*REGBYTES(sp) + LREG x26, 26*REGBYTES(sp) + LREG x27, 27*REGBYTES(sp) + LREG x28, 28*REGBYTES(sp) + LREG x29, 29*REGBYTES(sp) + LREG x30, 30*REGBYTES(sp) + LREG x31, 31*REGBYTES(sp) + addi sp, sp, 32*REGBYTES + mret + +#ifdef CONFIG_INIT_CRITICAL +cpu_init_crit: + ret +#endif -- cgit