linux-stable/arch/loongarch/kernel/head.S

159 lines
3.5 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 _kernel_asize /* Kernel image effective size */
.quad PHYS_LINK_KADDR /* Kernel image load offset from start of RAM */
.org 0x38 /* 0x20 ~ 0x37 reserved */
.long LINUX_PE_MAGIC
.long pe_header - _head /* Offset to the PE header */
pe_header:
__EFI_PE_HEADER
SYM_DATA(kernel_asize, .long _kernel_asize);
SYM_DATA(kernel_fsize, .long _kernel_fsize);
#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
JUMP_VIRT_ADDR t0, t1
/* 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
#ifdef CONFIG_PAGE_SIZE_4KB
li.d t0, 0
li.d t1, CSR_STFILL
csrxchg t0, t1, LOONGARCH_CSR_IMPCTL1
#endif
/* 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
#ifdef CONFIG_RELOCATABLE
bl relocate_kernel
#ifdef CONFIG_RANDOMIZE_BASE
/* Repoint the sp into the new kernel */
PTR_LI sp, (_THREAD_SIZE - PT_SIZE)
PTR_ADD sp, sp, tp
set_saved_sp sp, t0, t1
/* Jump to the new kernel: new_pc = current_pc + random_offset */
pcaddi t0, 0
add.d t0, t0, a0
jirl zero, t0, 0xc
#endif /* CONFIG_RANDOMIZE_BASE */
#endif /* CONFIG_RELOCATABLE */
#ifdef CONFIG_KASAN
bl kasan_early_init
#endif
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
JUMP_VIRT_ADDR t0, t1
#ifdef CONFIG_PAGE_SIZE_4KB
li.d t0, 0
li.d t1, CSR_STFILL
csrxchg t0, t1, LOONGARCH_CSR_IMPCTL1
#endif
/* 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, 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)