Kernel+LibC: Clean up assembly code

Some assembly files were previously inconsistently formatted.

- Use 4 spaces for indentation
- Use `.L` as the local label prefix
- Remove trailing whitespace
This commit is contained in:
Sönke Holz 2025-01-09 19:40:35 +01:00
parent 1e0e569273
commit 524f699ae2
4 changed files with 100 additions and 100 deletions

View file

@ -13,32 +13,32 @@
.global start .global start
.type start, @function .type start, @function
start: start:
// Let only core 0 continue, put other cores to sleep. // Let only core 0 continue, put other cores to sleep.
mrs x13, MPIDR_EL1 mrs x13, MPIDR_EL1
and x13, x13, 0xff and x13, x13, 0xff
cbnz x13, halt cbnz x13, halt
// Set the stack pointer register to the location defined in the linker script. // Set the stack pointer register to the location defined in the linker script.
adrp x14, end_of_initial_stack adrp x14, end_of_initial_stack
add x14, x14, :lo12:end_of_initial_stack add x14, x14, :lo12:end_of_initial_stack
mov sp, x14 mov sp, x14
// Clear BSS. // Clear BSS.
adrp x14, start_of_bss adrp x14, start_of_bss
add x14, x14, :lo12:start_of_bss add x14, x14, :lo12:start_of_bss
adrp x15, end_of_bss adrp x15, end_of_bss
add x15, x15, :lo12:end_of_bss add x15, x15, :lo12:end_of_bss
cmp x14, x15 cmp x14, x15
b.ge Lbss_clear_done b.ge .Lbss_clear_done
Lbss_clear_loop: .Lbss_clear_loop:
str xzr, [x14], #8 str xzr, [x14], #8
cmp x14, x15 cmp x14, x15
b.lt Lbss_clear_loop b.lt .Lbss_clear_loop
Lbss_clear_done: .Lbss_clear_done:
b pre_init b pre_init
halt: halt:
msr daifset, #2 msr daifset, #2
wfi wfi
b halt b halt

View file

@ -12,89 +12,89 @@
linux_header: linux_header:
.option push .option push
.option arch, -c .option arch, -c
j start // u32 code0 j start // u32 code0
j start // u32 code1 j start // u32 code1
.option pop .option pop
// This offset is needed, as otherwise U-Boot will try to load us at the same address where OpenSBI is loaded. // This offset is needed, as otherwise U-Boot will try to load us at the same address where OpenSBI is loaded.
// The value is the same that Linux uses. // The value is the same that Linux uses.
.dword 0x400000 // u64 text_offset .dword 0x400000 // u64 text_offset
.dword end_of_kernel_image - linux_header // u64 image_size .dword end_of_kernel_image - linux_header // u64 image_size
.dword 0 // u64 flags .dword 0 // u64 flags
.word 2 // u32 version .word 2 // u32 version
.word 0 // u32 res1 .word 0 // u32 res1
.dword 0 // u64 res2 .dword 0 // u64 res2
.ascii "RISCV\0\0\0" // u64 magic (deprecated) .ascii "RISCV\0\0\0" // u64 magic (deprecated)
.ascii "RSC\x5" // u32 magic2 .ascii "RSC\x5" // u32 magic2
.word 0 // u32 res3 .word 0 // u32 res3
.global start .global start
.type start, @function .type start, @function
start: start:
// We expect that only one hart jumps here and that we are running in supervisor mode. // We expect that only one hart jumps here and that we are running in supervisor mode.
// We also expect that an implementation of the RISC-V Supervisor Binary Interface is available. // We also expect that an implementation of the RISC-V Supervisor Binary Interface is available.
// Don't touch a0/a1 as we expect those registers to contain the hart ID // Don't touch a0/a1 as we expect those registers to contain the hart ID
// and a pointer to the Flattened Devicetree. // and a pointer to the Flattened Devicetree.
// Clear sstatus.SIE, which disables all interrupts in supervisor mode. // Clear sstatus.SIE, which disables all interrupts in supervisor mode.
csrci sstatus, 1 << 1 csrci sstatus, 1 << 1
// Also, disable all interrupts sources and mark them as non-pending. // Also, disable all interrupts sources and mark them as non-pending.
csrw sie, zero csrw sie, zero
csrw sip, zero csrw sip, zero
// TODO: maybe load the gp register here? // TODO: maybe load the gp register here?
// Clear the BSS. // Clear the BSS.
lla t0, start_of_bss lla t0, start_of_bss
lla t1, end_of_bss lla t1, end_of_bss
bgeu t0, t1, Lclear_bss_done bgeu t0, t1, .Lclear_bss_done
Lclear_bss_loop: .Lclear_bss_loop:
sd zero, (t0) sd zero, (t0)
addi t0, t0, 8 addi t0, t0, 8
bltu t0, t1, Lclear_bss_loop bltu t0, t1, .Lclear_bss_loop
Lclear_bss_done: .Lclear_bss_done:
// Set the stack pointer register to the location defined in the linker script. // Set the stack pointer register to the location defined in the linker script.
lla sp, end_of_initial_stack lla sp, end_of_initial_stack
// Zero all registers except sp, a0 and a1. // Zero all registers except sp, a0 and a1.
li ra, 0 li ra, 0
// sp // sp
li gp, 0 li gp, 0
li tp, 0 li tp, 0
li t0, 0 li t0, 0
li t1, 0 li t1, 0
li t2, 0 li t2, 0
li fp, 0 li fp, 0
li s1, 0 li s1, 0
// a0 // a0
// a1 // a1
li a2, 0 li a2, 0
li a3, 0 li a3, 0
li a4, 0 li a4, 0
li a5, 0 li a5, 0
li a6, 0 li a6, 0
li a7, 0 li a7, 0
li s2, 0 li s2, 0
li s3, 0 li s3, 0
li s4, 0 li s4, 0
li s5, 0 li s5, 0
li s6, 0 li s6, 0
li s7, 0 li s7, 0
li s8, 0 li s8, 0
li s9, 0 li s9, 0
li s10, 0 li s10, 0
li s11, 0 li s11, 0
li t3, 0 li t3, 0
li t4, 0 li t4, 0
li t5, 0 li t5, 0
li t6, 0 li t6, 0
// The trap handler expects sscratch to be zero if we are in supervisor mode. // The trap handler expects sscratch to be zero if we are in supervisor mode.
// sscratch contains the kernel stack pointer if we are in user mode. // sscratch contains the kernel stack pointer if we are in user mode.
csrw sscratch, zero csrw sscratch, zero
tail pre_init tail pre_init

View file

@ -136,7 +136,7 @@ print_no_halt:
/* /*
this function assumes that paging is disabled (or everything is mapped 1:1) this function assumes that paging is disabled (or everything is mapped 1:1)
param 1: pointer to string ended with null terminator (C string) param 1: pointer to string ended with null terminator (C string)
*/ */
@ -222,15 +222,15 @@ print_and_halt:
gdt_table_real_mode: gdt_table_real_mode:
.quad 0 /* Empty entry */ .quad 0 /* Empty entry */
.short 0xffff .short 0xffff
.short 0 .short 0
.byte 0 .byte 0
.byte 0b10011010 .byte 0b10011010
.byte 0b00001111 .byte 0b00001111
.byte 0x0 .byte 0x0
.short 0xffff .short 0xffff
.short 0 .short 0
.byte 0 .byte 0
.byte 0b10010010 .byte 0b10010010
.byte 0b00001111 .byte 0b00001111
@ -328,7 +328,7 @@ real_start:
mov $end_of_prekernel_image, %esi mov $end_of_prekernel_image, %esi
cmp $MAX_KERNEL_SIZE, %esi cmp $MAX_KERNEL_SIZE, %esi
jbe kernel_not_too_large jbe kernel_not_too_large
movl $kernel_image_too_big_string, %esi movl $kernel_image_too_big_string, %esi
pushl %esi pushl %esi
call print_and_halt call print_and_halt

View file

@ -42,7 +42,7 @@ sigsetjmp:
mov %rbp, (5 * 8)(%rdi) mov %rbp, (5 * 8)(%rdi)
mov %rsp, (6 * 8)(%rdi) mov %rsp, (6 * 8)(%rdi)
mov (%rsp), %rax // Grab return address mov (%rsp), %rax // Grab return address
mov %rax, (7 * 8)(%rdi) mov %rax, (7 * 8)(%rdi)
xor %eax, %eax xor %eax, %eax
ret ret