diff options
Diffstat (limited to 'arch/riscv/kernel/head.S')
| -rw-r--r-- | arch/riscv/kernel/head.S | 59 |
1 files changed, 42 insertions, 17 deletions
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index 370c66ce187a..0f1ba17e476f 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -1,14 +1,6 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright (C) 2012 Regents of the University of California - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation, version 2. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. */ #include <asm/thread_info.h> @@ -19,9 +11,41 @@ #include <asm/thread_info.h> #include <asm/page.h> #include <asm/csr.h> +#include <asm/image.h> __INIT ENTRY(_start) + /* + * Image header expected by Linux boot-loaders. The image header data + * structure is described in asm/image.h. + * Do not modify it without modifying the structure and all bootloaders + * that expects this header format!! + */ + /* jump to start kernel */ + j _start_kernel + /* reserved */ + .word 0 + .balign 8 +#if __riscv_xlen == 64 + /* Image load offset(2MB) from start of RAM */ + .dword 0x200000 +#else + /* Image load offset(4MB) from start of RAM */ + .dword 0x400000 +#endif + /* Effective size of kernel image */ + .dword _end - _start + .dword __HEAD_FLAGS + .word RISCV_HEADER_VERSION + .word 0 + .dword 0 + .asciz RISCV_IMAGE_MAGIC + .word 0 + .balign 4 + .word 0 + +.global _start_kernel +_start_kernel: /* Mask all interrupts */ csrw CSR_SIE, zero csrw CSR_SIP, zero @@ -63,7 +87,9 @@ clear_bss_done: /* Initialize page tables and relocate to virtual addresses */ la sp, init_thread_union + THREAD_SIZE + mv a0, s1 call setup_vm + la a0, early_pg_dir call relocate /* Restore C environment */ @@ -72,25 +98,23 @@ clear_bss_done: la sp, init_thread_union + THREAD_SIZE /* Start the kernel */ - mv a0, s1 call parse_dtb tail start_kernel relocate: /* Relocate return address */ li a1, PAGE_OFFSET - la a0, _start - sub a1, a1, a0 + la a2, _start + sub a1, a1, a2 add ra, ra, a1 /* Point stvec to virtual address of intruction after satp write */ - la a0, 1f - add a0, a0, a1 - csrw CSR_STVEC, a0 + la a2, 1f + add a2, a2, a1 + csrw CSR_STVEC, a2 /* Compute satp for kernel page tables, but don't load it yet */ - la a2, swapper_pg_dir - srl a2, a2, PAGE_SHIFT + srl a2, a0, PAGE_SHIFT li a1, SATP_MODE or a2, a2, a1 @@ -156,6 +180,7 @@ relocate: fence /* Enable virtual memory and relocate to virtual address */ + la a0, swapper_pg_dir call relocate tail smp_callin |