WSL2-Linux-Kernel/arch/arm/boot/compressed/head-sa1100.S

48 строки
1.2 KiB
ArmAsm

/*
* linux/arch/arm/boot/compressed/head-sa1100.S
*
* Copyright (C) 1999 Nicolas Pitre <nico@cam.org>
*
* SA1100 specific tweaks. This is merged into head.S by the linker.
*
*/
#include <linux/linkage.h>
#include <asm/mach-types.h>
.section ".start", "ax"
__SA1100_start:
@ Preserve r8/r7 i.e. kernel entry values
#ifdef CONFIG_SA1100_COLLIE
mov r7, #MACH_TYPE_COLLIE
#endif
#ifdef CONFIG_SA1100_SIMPAD
@ UNTIL we've something like an open bootldr
mov r7, #MACH_TYPE_SIMPAD @should be 87
#endif
mrc p15, 0, r0, c1, c0, 0 @ read control reg
ands r0, r0, #0x0d
beq 99f
@ Data cache might be active.
@ Be sure to flush kernel binary out of the cache,
@ whatever state it is, before it is turned off.
@ This is done by fetching through currently executed
@ memory to be sure we hit the same cache.
bic r2, pc, #0x1f
add r3, r2, #0x4000 @ 16 kb is quite enough...
1: ldr r0, [r2], #32
teq r2, r3
bne 1b
mcr p15, 0, r0, c7, c10, 4 @ drain WB
mcr p15, 0, r0, c7, c7, 0 @ flush I & D caches
@ disabling MMU and caches
mrc p15, 0, r0, c1, c0, 0 @ read control reg
bic r0, r0, #0x0d @ clear WB, DC, MMU
bic r0, r0, #0x1000 @ clear Icache
mcr p15, 0, r0, c1, c0, 0
99: