linuxdebug/arch/loongarch/kernel/head.S

131 lines
3.0 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#include <linux/init.h>
#include <linux/threads.h>
#include <asm/addrspace.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/bug.h>
#include <asm/regdef.h>
#include <asm/loongarch.h>
#include <asm/stackframe.h>
#ifdef CONFIG_EFI_STUB
#include "efi-header.S"
__HEAD
_head:
.word MZ_MAGIC /* "MZ", MS-DOS header */
.org 0x8
.dword kernel_entry /* Kernel entry point */
.dword _end - _text /* Kernel image effective size */
.quad 0 /* Kernel image load offset from start of RAM */
.org 0x3c /* 0x20 ~ 0x3b reserved */
.long pe_header - _head /* Offset to the PE header */
pe_header:
__EFI_PE_HEADER
SYM_DATA(kernel_asize, .long _end - _text);
SYM_DATA(kernel_fsize, .long _edata - _text);
SYM_DATA(kernel_offset, .long kernel_offset - _text);
#endif
__REF
.align 12
SYM_CODE_START(kernel_entry) # kernel entry point
/* Config direct window and set PG */
li.d t0, CSR_DMW0_INIT # UC, PLV0, 0x8000 xxxx xxxx xxxx
csrwr t0, LOONGARCH_CSR_DMWIN0
li.d t0, CSR_DMW1_INIT # CA, PLV0, 0x9000 xxxx xxxx xxxx
csrwr t0, LOONGARCH_CSR_DMWIN1
/* We might not get launched at the address the kernel is linked to,
so we jump there. */
la.abs t0, 0f
jr t0
0:
/* Enable PG */
li.w t0, 0xb0 # PLV=0, IE=0, PG=1
csrwr t0, LOONGARCH_CSR_CRMD
li.w t0, 0x04 # PLV=0, PIE=1, PWE=0
csrwr t0, LOONGARCH_CSR_PRMD
li.w t0, 0x00 # FPE=0, SXE=0, ASXE=0, BTE=0
csrwr t0, LOONGARCH_CSR_EUEN
la.pcrel t0, __bss_start # clear .bss
st.d zero, t0, 0
la.pcrel t1, __bss_stop - LONGSIZE
1:
addi.d t0, t0, LONGSIZE
st.d zero, t0, 0
bne t0, t1, 1b
la.pcrel t0, fw_arg0
st.d a0, t0, 0 # firmware arguments
la.pcrel t0, fw_arg1
st.d a1, t0, 0
la.pcrel t0, fw_arg2
st.d a2, t0, 0
/* KSave3 used for percpu base, initialized as 0 */
csrwr zero, PERCPU_BASE_KS
/* GPR21 used for percpu base (runtime), initialized as 0 */
move u0, zero
la.pcrel tp, init_thread_union
/* Set the SP after an empty pt_regs. */
PTR_LI sp, (_THREAD_SIZE - PT_SIZE)
PTR_ADD sp, sp, tp
set_saved_sp sp, t0, t1
bl start_kernel
ASM_BUG()
SYM_CODE_END(kernel_entry)
#ifdef CONFIG_SMP
/*
* SMP slave cpus entry point. Board specific code for bootstrap calls this
* function after setting up the stack and tp registers.
*/
SYM_CODE_START(smpboot_entry)
li.d t0, CSR_DMW0_INIT # UC, PLV0
csrwr t0, LOONGARCH_CSR_DMWIN0
li.d t0, CSR_DMW1_INIT # CA, PLV0
csrwr t0, LOONGARCH_CSR_DMWIN1
la.abs t0, 0f
jr t0
0:
/* Enable PG */
li.w t0, 0xb0 # PLV=0, IE=0, PG=1
csrwr t0, LOONGARCH_CSR_CRMD
li.w t0, 0x04 # PLV=0, PIE=1, PWE=0
csrwr t0, LOONGARCH_CSR_PRMD
li.w t0, 0x00 # FPE=0, SXE=0, ASXE=0, BTE=0
csrwr t0, LOONGARCH_CSR_EUEN
la.abs t0, cpuboot_data
ld.d sp, t0, CPU_BOOT_STACK
ld.d tp, t0, CPU_BOOT_TINFO
bl start_secondary
ASM_BUG()
SYM_CODE_END(smpboot_entry)
#endif /* CONFIG_SMP */
SYM_ENTRY(kernel_entry_end, SYM_L_GLOBAL, SYM_A_NONE)