1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * linux/arch/arm/boot/compressed/head-sa1100.S 4 * 5 * Copyright (C) 1999 Nicolas Pitre <nico@fluxnic.net> 6 * 7 * SA1100 specific tweaks. This is merged into head.S by the linker. 8 * 9 */ 10 11 #include <linux/linkage.h> 12 #include <asm/mach-types.h> 13 14 .section ".start", "ax" 15 .arch armv4 16 17 __SA1100_start: 18 19 @ Preserve r8/r7 i.e. kernel entry values 20 #ifdef CONFIG_SA1100_COLLIE 21 mov r7, #MACH_TYPE_COLLIE 22 #endif 23 mrc p15, 0, r0, c1, c0, 0 @ read control reg 24 ands r0, r0, #0x0d 25 beq 99f 26 27 @ Data cache might be active. 28 @ Be sure to flush kernel binary out of the cache, 29 @ whatever state it is, before it is turned off. 30 @ This is done by fetching through currently executed 31 @ memory to be sure we hit the same cache. 32 bic r2, pc, #0x1f 33 add r3, r2, #0x4000 @ 16 kb is quite enough... 34 1: ldr r0, [r2], #32 35 teq r2, r3 36 bne 1b 37 mcr p15, 0, r0, c7, c10, 4 @ drain WB 38 mcr p15, 0, r0, c7, c7, 0 @ flush I & D caches 39 40 @ disabling MMU and caches 41 mrc p15, 0, r0, c1, c0, 0 @ read control reg 42 bic r0, r0, #0x0d @ clear WB, DC, MMU 43 bic r0, r0, #0x1000 @ clear Icache 44 mcr p15, 0, r0, c1, c0, 0 45 99: 46