root/arch/arm/boot/compressed/head-xscale.S
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * linux/arch/arm/boot/compressed/head-xscale.S
 *
 * XScale specific tweaks.  This is merged into head.S by the linker.
 *
 */

#include <linux/linkage.h>

                .section        ".start", "ax"

__XScale_start:

                @ Preserve r8/r7 i.e. kernel entry values

                @ 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, #0x10000        @ 64 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, #0x05           @ clear DC, MMU
                bic     r0, r0, #0x1000         @ clear Icache
                mcr     p15, 0, r0, c1, c0, 0