xref: /openbmc/linux/arch/arm/kernel/head.S (revision 2ab4e8c0)
11da177e4SLinus Torvalds/*
21da177e4SLinus Torvalds *  linux/arch/arm/kernel/head.S
31da177e4SLinus Torvalds *
41da177e4SLinus Torvalds *  Copyright (C) 1994-2002 Russell King
5e65f38edSRussell King *  Copyright (c) 2003 ARM Limited
6e65f38edSRussell King *  All Rights Reserved
71da177e4SLinus Torvalds *
81da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or modify
91da177e4SLinus Torvalds * it under the terms of the GNU General Public License version 2 as
101da177e4SLinus Torvalds * published by the Free Software Foundation.
111da177e4SLinus Torvalds *
121da177e4SLinus Torvalds *  Kernel startup code for all 32-bit CPUs
131da177e4SLinus Torvalds */
141da177e4SLinus Torvalds#include <linux/linkage.h>
151da177e4SLinus Torvalds#include <linux/init.h>
161da177e4SLinus Torvalds
171da177e4SLinus Torvalds#include <asm/assembler.h>
18195864cfSRussell King#include <asm/cp15.h>
191da177e4SLinus Torvalds#include <asm/domain.h>
201da177e4SLinus Torvalds#include <asm/ptrace.h>
21e6ae744dSSam Ravnborg#include <asm/asm-offsets.h>
22f09b9979SNicolas Pitre#include <asm/memory.h>
234f7a1812SRussell King#include <asm/thread_info.h>
24e73fc88eSCatalin Marinas#include <asm/pgtable.h>
251da177e4SLinus Torvalds
2691a9fec0SRob Herring#if defined(CONFIG_DEBUG_LL) && !defined(CONFIG_DEBUG_SEMIHOSTING)
2791a9fec0SRob Herring#include CONFIG_DEBUG_LL_INCLUDE
28c293393fSJeremy Kerr#endif
29c293393fSJeremy Kerr
301da177e4SLinus Torvalds/*
3137d07b72SNicolas Pitre * swapper_pg_dir is the virtual address of the initial page table.
32f06b97ffSRussell King * We place the page tables 16K below KERNEL_RAM_VADDR.  Therefore, we must
33f06b97ffSRussell King * make sure that KERNEL_RAM_VADDR is correctly set.  Currently, we expect
3437d07b72SNicolas Pitre * the least significant 16 bits to be 0x8000, but we could probably
35f06b97ffSRussell King * relax this restriction to KERNEL_RAM_VADDR >= PAGE_OFFSET + 0x4000.
361da177e4SLinus Torvalds */
3772a20e22SRussell King#define KERNEL_RAM_VADDR	(PAGE_OFFSET + TEXT_OFFSET)
38f06b97ffSRussell King#if (KERNEL_RAM_VADDR & 0xffff) != 0x8000
39f06b97ffSRussell King#error KERNEL_RAM_VADDR must start at 0xXXXX8000
401da177e4SLinus Torvalds#endif
411da177e4SLinus Torvalds
421b6ba46bSCatalin Marinas#ifdef CONFIG_ARM_LPAE
431b6ba46bSCatalin Marinas	/* LPAE requires an additional page for the PGD */
441b6ba46bSCatalin Marinas#define PG_DIR_SIZE	0x5000
451b6ba46bSCatalin Marinas#define PMD_ORDER	3
461b6ba46bSCatalin Marinas#else
47e73fc88eSCatalin Marinas#define PG_DIR_SIZE	0x4000
48e73fc88eSCatalin Marinas#define PMD_ORDER	2
491b6ba46bSCatalin Marinas#endif
50e73fc88eSCatalin Marinas
511da177e4SLinus Torvalds	.globl	swapper_pg_dir
52e73fc88eSCatalin Marinas	.equ	swapper_pg_dir, KERNEL_RAM_VADDR - PG_DIR_SIZE
531da177e4SLinus Torvalds
5472a20e22SRussell King	.macro	pgtbl, rd, phys
552ab4e8c0SChristopher Covington	add	\rd, \phys, #TEXT_OFFSET
562ab4e8c0SChristopher Covington	sub	\rd, \rd, #PG_DIR_SIZE
571da177e4SLinus Torvalds	.endm
5837d07b72SNicolas Pitre
591da177e4SLinus Torvalds/*
601da177e4SLinus Torvalds * Kernel startup entry point.
611da177e4SLinus Torvalds * ---------------------------
621da177e4SLinus Torvalds *
631da177e4SLinus Torvalds * This is normally called from the decompressor code.  The requirements
641da177e4SLinus Torvalds * are: MMU = off, D-cache = off, I-cache = dont care, r0 = 0,
654c2896e8SGrant Likely * r1 = machine nr, r2 = atags or dtb pointer.
661da177e4SLinus Torvalds *
671da177e4SLinus Torvalds * This code is mostly position independent, so if you link the kernel at
681da177e4SLinus Torvalds * 0xc0008000, you call this at __pa(0xc0008000).
691da177e4SLinus Torvalds *
701da177e4SLinus Torvalds * See linux/arch/arm/tools/mach-types for the complete list of machine
711da177e4SLinus Torvalds * numbers for r1.
721da177e4SLinus Torvalds *
731da177e4SLinus Torvalds * We're trying to keep crap to a minimum; DO NOT add any machine specific
741da177e4SLinus Torvalds * crap here - that's what the boot loader (or in extreme, well justified
751da177e4SLinus Torvalds * circumstances, zImage) is for.
761da177e4SLinus Torvalds */
77540b5738SDave Martin	.arm
78540b5738SDave Martin
792abc1c50STim Abbott	__HEAD
801da177e4SLinus TorvaldsENTRY(stext)
8197bcb0feSBen Dooks ARM_BE8(setend	be )			@ ensure we are in BE8 mode
82540b5738SDave Martin
83540b5738SDave Martin THUMB(	adr	r9, BSYM(1f)	)	@ Kernel is always entered in ARM.
84540b5738SDave Martin THUMB(	bx	r9		)	@ If this is a Thumb-2 kernel,
85540b5738SDave Martin THUMB(	.thumb			)	@ switch to Thumb now.
86540b5738SDave Martin THUMB(1:			)
87540b5738SDave Martin
8880c59dafSDave Martin#ifdef CONFIG_ARM_VIRT_EXT
8980c59dafSDave Martin	bl	__hyp_stub_install
9080c59dafSDave Martin#endif
9180c59dafSDave Martin	@ ensure svc mode and all interrupts masked
9280c59dafSDave Martin	safe_svcmode_maskall r9
9380c59dafSDave Martin
940f44ba1dSRussell King	mrc	p15, 0, r9, c0, c0		@ get processor id
951da177e4SLinus Torvalds	bl	__lookup_processor_type		@ r5=procinfo r9=cpuid
961da177e4SLinus Torvalds	movs	r10, r5				@ invalid processor (r5=0)?
97a75e5248SDave Martin THUMB( it	eq )		@ force fixup-able long branch encoding
981da177e4SLinus Torvalds	beq	__error_p			@ yes, error 'p'
990eb0511dSRussell King
100294064f5SCatalin Marinas#ifdef CONFIG_ARM_LPAE
101294064f5SCatalin Marinas	mrc	p15, 0, r3, c0, c1, 4		@ read ID_MMFR0
102294064f5SCatalin Marinas	and	r3, r3, #0xf			@ extract VMSA support
103294064f5SCatalin Marinas	cmp	r3, #5				@ long-descriptor translation table format?
104294064f5SCatalin Marinas THUMB( it	lo )				@ force fixup-able long branch encoding
105294064f5SCatalin Marinas	blo	__error_p			@ only classic page table format
106294064f5SCatalin Marinas#endif
107294064f5SCatalin Marinas
10872a20e22SRussell King#ifndef CONFIG_XIP_KERNEL
10972a20e22SRussell King	adr	r3, 2f
11072a20e22SRussell King	ldmia	r3, {r4, r8}
11172a20e22SRussell King	sub	r4, r3, r4			@ (PHYS_OFFSET - PAGE_OFFSET)
11272a20e22SRussell King	add	r8, r8, r4			@ PHYS_OFFSET
11372a20e22SRussell King#else
114b713aa0bSRussell King	ldr	r8, =PLAT_PHYS_OFFSET		@ always constant in this case
11572a20e22SRussell King#endif
11672a20e22SRussell King
1170eb0511dSRussell King	/*
1184c2896e8SGrant Likely	 * r1 = machine no, r2 = atags or dtb,
11972a20e22SRussell King	 * r8 = phys_offset, r9 = cpuid, r10 = procinfo
1200eb0511dSRussell King	 */
1219d20fdd5SBill Gatliff	bl	__vet_atags
122f00ec48fSRussell King#ifdef CONFIG_SMP_ON_UP
123f00ec48fSRussell King	bl	__fixup_smp
124f00ec48fSRussell King#endif
125dc21af99SRussell King#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
126dc21af99SRussell King	bl	__fixup_pv_table
127dc21af99SRussell King#endif
1281da177e4SLinus Torvalds	bl	__create_page_tables
1291da177e4SLinus Torvalds
1301da177e4SLinus Torvalds	/*
1311da177e4SLinus Torvalds	 * The following calls CPU specific code in a position independent
1321da177e4SLinus Torvalds	 * manner.  See arch/arm/mm/proc-*.S for details.  r10 = base of
1336fc31d54SRussell King	 * xxx_proc_info structure selected by __lookup_processor_type
1341da177e4SLinus Torvalds	 * above.  On return, the CPU will be ready for the MMU to be
1351da177e4SLinus Torvalds	 * turned on, and r0 will hold the CPU control register value.
1361da177e4SLinus Torvalds	 */
137a4ae4134SRussell King	ldr	r13, =__mmap_switched		@ address to jump to after
1381da177e4SLinus Torvalds						@ mmu has been enabled
13900945010SRussell King	adr	lr, BSYM(1f)			@ return (PIC) address
140d427958aSCatalin Marinas	mov	r8, r4				@ set TTBR1 to swapper_pg_dir
141b86040a5SCatalin Marinas ARM(	add	pc, r10, #PROCINFO_INITFUNC	)
142b86040a5SCatalin Marinas THUMB(	add	r12, r10, #PROCINFO_INITFUNC	)
143b86040a5SCatalin Marinas THUMB(	mov	pc, r12				)
14400945010SRussell King1:	b	__enable_mmu
14593ed3970SCatalin MarinasENDPROC(stext)
146a4ae4134SRussell King	.ltorg
14772a20e22SRussell King#ifndef CONFIG_XIP_KERNEL
14872a20e22SRussell King2:	.long	.
14972a20e22SRussell King	.long	PAGE_OFFSET
15072a20e22SRussell King#endif
1511da177e4SLinus Torvalds
1521da177e4SLinus Torvalds/*
1531da177e4SLinus Torvalds * Setup the initial page tables.  We only setup the barest
1541da177e4SLinus Torvalds * amount which are required to get the kernel running, which
1551da177e4SLinus Torvalds * generally means mapping in the kernel code.
1561da177e4SLinus Torvalds *
15772a20e22SRussell King * r8 = phys_offset, r9 = cpuid, r10 = procinfo
1581da177e4SLinus Torvalds *
1591da177e4SLinus Torvalds * Returns:
160786f1b73SRussell King *  r0, r3, r5-r7 corrupted
1614756dcbfSCyril Chemparathy *  r4 = page table (see ARCH_PGD_SHIFT in asm/memory.h)
1621da177e4SLinus Torvalds */
1631da177e4SLinus Torvalds__create_page_tables:
16472a20e22SRussell King	pgtbl	r4, r8				@ page table address
1651da177e4SLinus Torvalds
1661da177e4SLinus Torvalds	/*
167e73fc88eSCatalin Marinas	 * Clear the swapper page table
1681da177e4SLinus Torvalds	 */
1691da177e4SLinus Torvalds	mov	r0, r4
1701da177e4SLinus Torvalds	mov	r3, #0
171e73fc88eSCatalin Marinas	add	r6, r0, #PG_DIR_SIZE
1721da177e4SLinus Torvalds1:	str	r3, [r0], #4
1731da177e4SLinus Torvalds	str	r3, [r0], #4
1741da177e4SLinus Torvalds	str	r3, [r0], #4
1751da177e4SLinus Torvalds	str	r3, [r0], #4
1761da177e4SLinus Torvalds	teq	r0, r6
1771da177e4SLinus Torvalds	bne	1b
1781da177e4SLinus Torvalds
1791b6ba46bSCatalin Marinas#ifdef CONFIG_ARM_LPAE
1801b6ba46bSCatalin Marinas	/*
1811b6ba46bSCatalin Marinas	 * Build the PGD table (first level) to point to the PMD table. A PGD
1821b6ba46bSCatalin Marinas	 * entry is 64-bit wide.
1831b6ba46bSCatalin Marinas	 */
1841b6ba46bSCatalin Marinas	mov	r0, r4
1851b6ba46bSCatalin Marinas	add	r3, r4, #0x1000			@ first PMD table address
1861b6ba46bSCatalin Marinas	orr	r3, r3, #3			@ PGD block type
1871b6ba46bSCatalin Marinas	mov	r6, #4				@ PTRS_PER_PGD
1881b6ba46bSCatalin Marinas	mov	r7, #1 << (55 - 32)		@ L_PGD_SWAPPER
189d61947a1SWill Deacon1:
190d61947a1SWill Deacon#ifdef CONFIG_CPU_ENDIAN_BE8
1911b6ba46bSCatalin Marinas	str	r7, [r0], #4			@ set top PGD entry bits
192d61947a1SWill Deacon	str	r3, [r0], #4			@ set bottom PGD entry bits
193d61947a1SWill Deacon#else
194d61947a1SWill Deacon	str	r3, [r0], #4			@ set bottom PGD entry bits
195d61947a1SWill Deacon	str	r7, [r0], #4			@ set top PGD entry bits
196d61947a1SWill Deacon#endif
1971b6ba46bSCatalin Marinas	add	r3, r3, #0x1000			@ next PMD table
1981b6ba46bSCatalin Marinas	subs	r6, r6, #1
1991b6ba46bSCatalin Marinas	bne	1b
2001b6ba46bSCatalin Marinas
2011b6ba46bSCatalin Marinas	add	r4, r4, #0x1000			@ point to the PMD tables
202d61947a1SWill Deacon#ifdef CONFIG_CPU_ENDIAN_BE8
203d61947a1SWill Deacon	add	r4, r4, #4			@ we only write the bottom word
204d61947a1SWill Deacon#endif
2051b6ba46bSCatalin Marinas#endif
2061b6ba46bSCatalin Marinas
2078799ee9fSRussell King	ldr	r7, [r10, #PROCINFO_MM_MMUFLAGS] @ mm_mmuflags
2081da177e4SLinus Torvalds
2091da177e4SLinus Torvalds	/*
210786f1b73SRussell King	 * Create identity mapping to cater for __enable_mmu.
211786f1b73SRussell King	 * This identity mapping will be removed by paging_init().
2121da177e4SLinus Torvalds	 */
21372662e01SWill Deacon	adr	r0, __turn_mmu_on_loc
214786f1b73SRussell King	ldmia	r0, {r3, r5, r6}
215786f1b73SRussell King	sub	r0, r0, r3			@ virt->phys offset
21672662e01SWill Deacon	add	r5, r5, r0			@ phys __turn_mmu_on
21772662e01SWill Deacon	add	r6, r6, r0			@ phys __turn_mmu_on_end
218e73fc88eSCatalin Marinas	mov	r5, r5, lsr #SECTION_SHIFT
219e73fc88eSCatalin Marinas	mov	r6, r6, lsr #SECTION_SHIFT
220786f1b73SRussell King
221e73fc88eSCatalin Marinas1:	orr	r3, r7, r5, lsl #SECTION_SHIFT	@ flags + kernel base
222e73fc88eSCatalin Marinas	str	r3, [r4, r5, lsl #PMD_ORDER]	@ identity mapping
223e73fc88eSCatalin Marinas	cmp	r5, r6
224e73fc88eSCatalin Marinas	addlo	r5, r5, #1			@ next section
225e73fc88eSCatalin Marinas	blo	1b
2261da177e4SLinus Torvalds
2271da177e4SLinus Torvalds	/*
2289fa16b77SNicolas Pitre	 * Map our RAM from the start to the end of the kernel .bss section.
2291da177e4SLinus Torvalds	 */
2309fa16b77SNicolas Pitre	add	r0, r4, #PAGE_OFFSET >> (SECTION_SHIFT - PMD_ORDER)
2319fa16b77SNicolas Pitre	ldr	r6, =(_end - 1)
2329fa16b77SNicolas Pitre	orr	r3, r8, r7
2339fa16b77SNicolas Pitre	add	r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER)
2349fa16b77SNicolas Pitre1:	str	r3, [r0], #1 << PMD_ORDER
2359fa16b77SNicolas Pitre	add	r3, r3, #1 << SECTION_SHIFT
2369fa16b77SNicolas Pitre	cmp	r0, r6
2379fa16b77SNicolas Pitre	bls	1b
2389fa16b77SNicolas Pitre
2399fa16b77SNicolas Pitre#ifdef CONFIG_XIP_KERNEL
2409fa16b77SNicolas Pitre	/*
2419fa16b77SNicolas Pitre	 * Map the kernel image separately as it is not located in RAM.
2429fa16b77SNicolas Pitre	 */
2439fa16b77SNicolas Pitre#define XIP_START XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR)
244786f1b73SRussell King	mov	r3, pc
245e73fc88eSCatalin Marinas	mov	r3, r3, lsr #SECTION_SHIFT
246e73fc88eSCatalin Marinas	orr	r3, r7, r3, lsl #SECTION_SHIFT
2479fa16b77SNicolas Pitre	add	r0, r4,  #(XIP_START & 0xff000000) >> (SECTION_SHIFT - PMD_ORDER)
2489fa16b77SNicolas Pitre	str	r3, [r0, #((XIP_START & 0x00f00000) >> SECTION_SHIFT) << PMD_ORDER]!
2499fa16b77SNicolas Pitre	ldr	r6, =(_edata_loc - 1)
250e73fc88eSCatalin Marinas	add	r0, r0, #1 << PMD_ORDER
251e73fc88eSCatalin Marinas	add	r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER)
252e98ff7f6SNicolas Pitre1:	cmp	r0, r6
253e73fc88eSCatalin Marinas	add	r3, r3, #1 << SECTION_SHIFT
254e73fc88eSCatalin Marinas	strls	r3, [r0], #1 << PMD_ORDER
255e98ff7f6SNicolas Pitre	bls	1b
256ec3622d9SNicolas Pitre#endif
257ec3622d9SNicolas Pitre
2581da177e4SLinus Torvalds	/*
2599fa16b77SNicolas Pitre	 * Then map boot params address in r2 if specified.
2606f16f499SNicolas Pitre	 * We map 2 sections in case the ATAGs/DTB crosses a section boundary.
2611da177e4SLinus Torvalds	 */
262e73fc88eSCatalin Marinas	mov	r0, r2, lsr #SECTION_SHIFT
263e73fc88eSCatalin Marinas	movs	r0, r0, lsl #SECTION_SHIFT
2649fa16b77SNicolas Pitre	subne	r3, r0, r8
2659fa16b77SNicolas Pitre	addne	r3, r3, #PAGE_OFFSET
2669fa16b77SNicolas Pitre	addne	r3, r4, r3, lsr #(SECTION_SHIFT - PMD_ORDER)
2679fa16b77SNicolas Pitre	orrne	r6, r7, r0
2686f16f499SNicolas Pitre	strne	r6, [r3], #1 << PMD_ORDER
2696f16f499SNicolas Pitre	addne	r6, r6, #1 << SECTION_SHIFT
2709fa16b77SNicolas Pitre	strne	r6, [r3]
2711da177e4SLinus Torvalds
2724e1db26aSPaul Bolle#if defined(CONFIG_ARM_LPAE) && defined(CONFIG_CPU_ENDIAN_BE8)
273d61947a1SWill Deacon	sub	r4, r4, #4			@ Fixup page table pointer
274d61947a1SWill Deacon						@ for 64-bit descriptors
275d61947a1SWill Deacon#endif
276d61947a1SWill Deacon
277c77b0427SRussell King#ifdef CONFIG_DEBUG_LL
2789b5a146aSNicolas Pitre#if !defined(CONFIG_DEBUG_ICEDCC) && !defined(CONFIG_DEBUG_SEMIHOSTING)
2791da177e4SLinus Torvalds	/*
2801da177e4SLinus Torvalds	 * Map in IO space for serial debugging.
2811da177e4SLinus Torvalds	 * This allows debug messages to be output
2821da177e4SLinus Torvalds	 * via a serial console before paging_init.
2831da177e4SLinus Torvalds	 */
284639da5eeSNicolas Pitre	addruart r7, r3, r0
285c293393fSJeremy Kerr
286e73fc88eSCatalin Marinas	mov	r3, r3, lsr #SECTION_SHIFT
287e73fc88eSCatalin Marinas	mov	r3, r3, lsl #PMD_ORDER
288c293393fSJeremy Kerr
2891da177e4SLinus Torvalds	add	r0, r4, r3
290e73fc88eSCatalin Marinas	mov	r3, r7, lsr #SECTION_SHIFT
291c293393fSJeremy Kerr	ldr	r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags
292e73fc88eSCatalin Marinas	orr	r3, r7, r3, lsl #SECTION_SHIFT
2931b6ba46bSCatalin Marinas#ifdef CONFIG_ARM_LPAE
2941b6ba46bSCatalin Marinas	mov	r7, #1 << (54 - 32)		@ XN
295d61947a1SWill Deacon#ifdef CONFIG_CPU_ENDIAN_BE8
296d61947a1SWill Deacon	str	r7, [r0], #4
297d61947a1SWill Deacon	str	r3, [r0], #4
298d61947a1SWill Deacon#else
299d61947a1SWill Deacon	str	r3, [r0], #4
300d61947a1SWill Deacon	str	r7, [r0], #4
301d61947a1SWill Deacon#endif
3021b6ba46bSCatalin Marinas#else
3031b6ba46bSCatalin Marinas	orr	r3, r3, #PMD_SECT_XN
304f67860a7SNicolas Pitre	str	r3, [r0], #4
3051b6ba46bSCatalin Marinas#endif
306c293393fSJeremy Kerr
3079b5a146aSNicolas Pitre#else /* CONFIG_DEBUG_ICEDCC || CONFIG_DEBUG_SEMIHOSTING */
3089b5a146aSNicolas Pitre	/* we don't need any serial debugging mappings */
309c293393fSJeremy Kerr	ldr	r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags
3109b5a146aSNicolas Pitre#endif
311c293393fSJeremy Kerr
3121da177e4SLinus Torvalds#if defined(CONFIG_ARCH_NETWINDER) || defined(CONFIG_ARCH_CATS)
3131da177e4SLinus Torvalds	/*
3143c0bdac3SRussell King	 * If we're using the NetWinder or CATS, we also need to map
3153c0bdac3SRussell King	 * in the 16550-type serial port for the debug messages
3161da177e4SLinus Torvalds	 */
317e73fc88eSCatalin Marinas	add	r0, r4, #0xff000000 >> (SECTION_SHIFT - PMD_ORDER)
318c77b0427SRussell King	orr	r3, r7, #0x7c000000
319c77b0427SRussell King	str	r3, [r0]
3201da177e4SLinus Torvalds#endif
3211da177e4SLinus Torvalds#ifdef CONFIG_ARCH_RPC
3221da177e4SLinus Torvalds	/*
3231da177e4SLinus Torvalds	 * Map in screen at 0x02000000 & SCREEN2_BASE
3241da177e4SLinus Torvalds	 * Similar reasons here - for debug.  This is
3251da177e4SLinus Torvalds	 * only for Acorn RiscPC architectures.
3261da177e4SLinus Torvalds	 */
327e73fc88eSCatalin Marinas	add	r0, r4, #0x02000000 >> (SECTION_SHIFT - PMD_ORDER)
328c77b0427SRussell King	orr	r3, r7, #0x02000000
3291da177e4SLinus Torvalds	str	r3, [r0]
330e73fc88eSCatalin Marinas	add	r0, r4, #0xd8000000 >> (SECTION_SHIFT - PMD_ORDER)
3311da177e4SLinus Torvalds	str	r3, [r0]
3321da177e4SLinus Torvalds#endif
333c77b0427SRussell King#endif
3341b6ba46bSCatalin Marinas#ifdef CONFIG_ARM_LPAE
3351b6ba46bSCatalin Marinas	sub	r4, r4, #0x1000		@ point to the PGD table
3364756dcbfSCyril Chemparathy	mov	r4, r4, lsr #ARCH_PGD_SHIFT
3371b6ba46bSCatalin Marinas#endif
3381da177e4SLinus Torvalds	mov	pc, lr
33993ed3970SCatalin MarinasENDPROC(__create_page_tables)
3401da177e4SLinus Torvalds	.ltorg
3414f79a5ddSDave Martin	.align
34272662e01SWill Deacon__turn_mmu_on_loc:
343786f1b73SRussell King	.long	.
34472662e01SWill Deacon	.long	__turn_mmu_on
34572662e01SWill Deacon	.long	__turn_mmu_on_end
3461da177e4SLinus Torvalds
34700945010SRussell King#if defined(CONFIG_SMP)
3482449189bSRussell King	.text
34900945010SRussell KingENTRY(secondary_startup)
35000945010SRussell King	/*
35100945010SRussell King	 * Common entry point for secondary CPUs.
35200945010SRussell King	 *
35300945010SRussell King	 * Ensure that we're in SVC mode, and IRQs are disabled.  Lookup
35400945010SRussell King	 * the processor type - there is no need to check the machine type
35500945010SRussell King	 * as it has already been validated by the primary processor.
35600945010SRussell King	 */
35797bcb0feSBen Dooks
35897bcb0feSBen Dooks ARM_BE8(setend	be)				@ ensure we are in BE8 mode
35997bcb0feSBen Dooks
36080c59dafSDave Martin#ifdef CONFIG_ARM_VIRT_EXT
3616e484be1SMarc Zyngier	bl	__hyp_stub_install_secondary
36280c59dafSDave Martin#endif
36380c59dafSDave Martin	safe_svcmode_maskall r9
36480c59dafSDave Martin
36500945010SRussell King	mrc	p15, 0, r9, c0, c0		@ get processor id
36600945010SRussell King	bl	__lookup_processor_type
36700945010SRussell King	movs	r10, r5				@ invalid processor?
36800945010SRussell King	moveq	r0, #'p'			@ yes, error 'p'
369a75e5248SDave Martin THUMB( it	eq )		@ force fixup-able long branch encoding
37000945010SRussell King	beq	__error_p
37100945010SRussell King
37200945010SRussell King	/*
37300945010SRussell King	 * Use the page tables supplied from  __cpu_up.
37400945010SRussell King	 */
37500945010SRussell King	adr	r4, __secondary_data
37600945010SRussell King	ldmia	r4, {r5, r7, r12}		@ address to jump to after
377d427958aSCatalin Marinas	sub	lr, r4, r5			@ mmu has been enabled
378d427958aSCatalin Marinas	ldr	r4, [r7, lr]			@ get secondary_data.pgdir
379d427958aSCatalin Marinas	add	r7, r7, #4
380d427958aSCatalin Marinas	ldr	r8, [r7, lr]			@ get secondary_data.swapper_pg_dir
38100945010SRussell King	adr	lr, BSYM(__enable_mmu)		@ return address
38200945010SRussell King	mov	r13, r12			@ __secondary_switched address
38300945010SRussell King ARM(	add	pc, r10, #PROCINFO_INITFUNC	) @ initialise processor
38400945010SRussell King						  @ (return control reg)
38500945010SRussell King THUMB(	add	r12, r10, #PROCINFO_INITFUNC	)
38600945010SRussell King THUMB(	mov	pc, r12				)
38700945010SRussell KingENDPROC(secondary_startup)
38800945010SRussell King
38900945010SRussell King	/*
39000945010SRussell King	 * r6  = &secondary_data
39100945010SRussell King	 */
39200945010SRussell KingENTRY(__secondary_switched)
39300945010SRussell King	ldr	sp, [r7, #4]			@ get secondary_data.stack
39400945010SRussell King	mov	fp, #0
39500945010SRussell King	b	secondary_start_kernel
39600945010SRussell KingENDPROC(__secondary_switched)
39700945010SRussell King
3984f79a5ddSDave Martin	.align
3994f79a5ddSDave Martin
40000945010SRussell King	.type	__secondary_data, %object
40100945010SRussell King__secondary_data:
40200945010SRussell King	.long	.
40300945010SRussell King	.long	secondary_data
40400945010SRussell King	.long	__secondary_switched
40500945010SRussell King#endif /* defined(CONFIG_SMP) */
40600945010SRussell King
40700945010SRussell King
40800945010SRussell King
40900945010SRussell King/*
41000945010SRussell King * Setup common bits before finally enabling the MMU.  Essentially
41100945010SRussell King * this is just loading the page table pointer and domain access
41200945010SRussell King * registers.
413865a4faeSRussell King *
414865a4faeSRussell King *  r0  = cp#15 control register
415865a4faeSRussell King *  r1  = machine ID
4164c2896e8SGrant Likely *  r2  = atags or dtb pointer
4174756dcbfSCyril Chemparathy *  r4  = page table (see ARCH_PGD_SHIFT in asm/memory.h)
418865a4faeSRussell King *  r9  = processor ID
419865a4faeSRussell King *  r13 = *virtual* address to jump to upon completion
42000945010SRussell King */
42100945010SRussell King__enable_mmu:
4228428e84dSCatalin Marinas#if defined(CONFIG_ALIGNMENT_TRAP) && __LINUX_ARM_ARCH__ < 6
42300945010SRussell King	orr	r0, r0, #CR_A
42400945010SRussell King#else
42500945010SRussell King	bic	r0, r0, #CR_A
42600945010SRussell King#endif
42700945010SRussell King#ifdef CONFIG_CPU_DCACHE_DISABLE
42800945010SRussell King	bic	r0, r0, #CR_C
42900945010SRussell King#endif
43000945010SRussell King#ifdef CONFIG_CPU_BPREDICT_DISABLE
43100945010SRussell King	bic	r0, r0, #CR_Z
43200945010SRussell King#endif
43300945010SRussell King#ifdef CONFIG_CPU_ICACHE_DISABLE
43400945010SRussell King	bic	r0, r0, #CR_I
43500945010SRussell King#endif
4364756dcbfSCyril Chemparathy#ifndef CONFIG_ARM_LPAE
43700945010SRussell King	mov	r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \
43800945010SRussell King		      domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \
43900945010SRussell King		      domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \
44000945010SRussell King		      domain_val(DOMAIN_IO, DOMAIN_CLIENT))
44100945010SRussell King	mcr	p15, 0, r5, c3, c0, 0		@ load domain access register
44200945010SRussell King	mcr	p15, 0, r4, c2, c0, 0		@ load page table pointer
4431b6ba46bSCatalin Marinas#endif
44400945010SRussell King	b	__turn_mmu_on
44500945010SRussell KingENDPROC(__enable_mmu)
44600945010SRussell King
44700945010SRussell King/*
44800945010SRussell King * Enable the MMU.  This completely changes the structure of the visible
44900945010SRussell King * memory space.  You will not be able to trace execution through this.
45000945010SRussell King * If you have an enquiry about this, *please* check the linux-arm-kernel
45100945010SRussell King * mailing list archives BEFORE sending another post to the list.
45200945010SRussell King *
45300945010SRussell King *  r0  = cp#15 control register
454865a4faeSRussell King *  r1  = machine ID
4554c2896e8SGrant Likely *  r2  = atags or dtb pointer
456865a4faeSRussell King *  r9  = processor ID
45700945010SRussell King *  r13 = *virtual* address to jump to upon completion
45800945010SRussell King *
45900945010SRussell King * other registers depend on the function called upon completion
46000945010SRussell King */
46100945010SRussell King	.align	5
4624e8ee7deSWill Deacon	.pushsection	.idmap.text, "ax"
4634e8ee7deSWill DeaconENTRY(__turn_mmu_on)
46400945010SRussell King	mov	r0, r0
465d675d0bcSWill Deacon	instr_sync
46600945010SRussell King	mcr	p15, 0, r0, c1, c0, 0		@ write control reg
46700945010SRussell King	mrc	p15, 0, r3, c0, c0, 0		@ read id reg
468d675d0bcSWill Deacon	instr_sync
46900945010SRussell King	mov	r3, r3
47000945010SRussell King	mov	r3, r13
47100945010SRussell King	mov	pc, r3
47272662e01SWill Deacon__turn_mmu_on_end:
47300945010SRussell KingENDPROC(__turn_mmu_on)
4744e8ee7deSWill Deacon	.popsection
47500945010SRussell King
4761da177e4SLinus Torvalds
477f00ec48fSRussell King#ifdef CONFIG_SMP_ON_UP
4784a9cb360SRussell King	__INIT
479f00ec48fSRussell King__fixup_smp:
480e98ff0f5SRussell King	and	r3, r9, #0x000f0000	@ architecture version
481e98ff0f5SRussell King	teq	r3, #0x000f0000		@ CPU ID supported?
482f00ec48fSRussell King	bne	__fixup_smp_on_up	@ no, assume UP
483f00ec48fSRussell King
484e98ff0f5SRussell King	bic	r3, r9, #0x00ff0000
485e98ff0f5SRussell King	bic	r3, r3, #0x0000000f	@ mask 0xff00fff0
486e98ff0f5SRussell King	mov	r4, #0x41000000
4870eb0511dSRussell King	orr	r4, r4, #0x0000b000
488e98ff0f5SRussell King	orr	r4, r4, #0x00000020	@ val 0x4100b020
489e98ff0f5SRussell King	teq	r3, r4			@ ARM 11MPCore?
490f00ec48fSRussell King	moveq	pc, lr			@ yes, assume SMP
491f00ec48fSRussell King
492f00ec48fSRussell King	mrc	p15, 0, r0, c0, c0, 5	@ read MPIDR
493e98ff0f5SRussell King	and	r0, r0, #0xc0000000	@ multiprocessing extensions and
494e98ff0f5SRussell King	teq	r0, #0x80000000		@ not part of a uniprocessor system?
495bc41b872SSantosh Shilimkar	bne    __fixup_smp_on_up	@ no, assume UP
496bc41b872SSantosh Shilimkar
497bc41b872SSantosh Shilimkar	@ Core indicates it is SMP. Check for Aegis SOC where a single
498bc41b872SSantosh Shilimkar	@ Cortex-A9 CPU is present but SMP operations fault.
499bc41b872SSantosh Shilimkar	mov	r4, #0x41000000
500bc41b872SSantosh Shilimkar	orr	r4, r4, #0x0000c000
501bc41b872SSantosh Shilimkar	orr	r4, r4, #0x00000090
502bc41b872SSantosh Shilimkar	teq	r3, r4			@ Check for ARM Cortex-A9
503bc41b872SSantosh Shilimkar	movne	pc, lr			@ Not ARM Cortex-A9,
504bc41b872SSantosh Shilimkar
505bc41b872SSantosh Shilimkar	@ If a future SoC *does* use 0x0 as the PERIPH_BASE, then the
506bc41b872SSantosh Shilimkar	@ below address check will need to be #ifdef'd or equivalent
507bc41b872SSantosh Shilimkar	@ for the Aegis platform.
508bc41b872SSantosh Shilimkar	mrc	p15, 4, r0, c15, c0	@ get SCU base address
509bc41b872SSantosh Shilimkar	teq	r0, #0x0		@ '0' on actual UP A9 hardware
510bc41b872SSantosh Shilimkar	beq	__fixup_smp_on_up	@ So its an A9 UP
511bc41b872SSantosh Shilimkar	ldr	r0, [r0, #4]		@ read SCU Config
51210593b2eSVictor KamenskyARM_BE8(rev	r0, r0)			@ byteswap if big endian
513bc41b872SSantosh Shilimkar	and	r0, r0, #0x3		@ number of CPUs
514bc41b872SSantosh Shilimkar	teq	r0, #0x0		@ is 1?
515bc41b872SSantosh Shilimkar	movne	pc, lr
516f00ec48fSRussell King
517f00ec48fSRussell King__fixup_smp_on_up:
518f00ec48fSRussell King	adr	r0, 1f
5190eb0511dSRussell King	ldmia	r0, {r3 - r5}
520f00ec48fSRussell King	sub	r3, r0, r3
5210eb0511dSRussell King	add	r4, r4, r3
5220eb0511dSRussell King	add	r5, r5, r3
5234a9cb360SRussell King	b	__do_fixup_smp_on_up
524f00ec48fSRussell KingENDPROC(__fixup_smp)
525f00ec48fSRussell King
5264f79a5ddSDave Martin	.align
527f00ec48fSRussell King1:	.word	.
528f00ec48fSRussell King	.word	__smpalt_begin
529f00ec48fSRussell King	.word	__smpalt_end
530f00ec48fSRussell King
531f00ec48fSRussell King	.pushsection .data
532f00ec48fSRussell King	.globl	smp_on_up
533f00ec48fSRussell Kingsmp_on_up:
534f00ec48fSRussell King	ALT_SMP(.long	1)
535f00ec48fSRussell King	ALT_UP(.long	0)
536f00ec48fSRussell King	.popsection
537f00ec48fSRussell King#endif
538f00ec48fSRussell King
5394a9cb360SRussell King	.text
5404a9cb360SRussell King__do_fixup_smp_on_up:
5414a9cb360SRussell King	cmp	r4, r5
5424a9cb360SRussell King	movhs	pc, lr
5434a9cb360SRussell King	ldmia	r4!, {r0, r6}
5444a9cb360SRussell King ARM(	str	r6, [r0, r3]	)
5454a9cb360SRussell King THUMB(	add	r0, r0, r3	)
5464a9cb360SRussell King#ifdef __ARMEB__
5474a9cb360SRussell King THUMB(	mov	r6, r6, ror #16	)	@ Convert word order for big-endian.
5484a9cb360SRussell King#endif
5494a9cb360SRussell King THUMB(	strh	r6, [r0], #2	)	@ For Thumb-2, store as two halfwords
5504a9cb360SRussell King THUMB(	mov	r6, r6, lsr #16	)	@ to be robust against misaligned r3.
5514a9cb360SRussell King THUMB(	strh	r6, [r0]	)
5524a9cb360SRussell King	b	__do_fixup_smp_on_up
5534a9cb360SRussell KingENDPROC(__do_fixup_smp_on_up)
5544a9cb360SRussell King
5554a9cb360SRussell KingENTRY(fixup_smp)
5564a9cb360SRussell King	stmfd	sp!, {r4 - r6, lr}
5574a9cb360SRussell King	mov	r4, r0
5584a9cb360SRussell King	add	r5, r0, r1
5594a9cb360SRussell King	mov	r3, #0
5604a9cb360SRussell King	bl	__do_fixup_smp_on_up
5614a9cb360SRussell King	ldmfd	sp!, {r4 - r6, pc}
5624a9cb360SRussell KingENDPROC(fixup_smp)
5634a9cb360SRussell King
564830fd4d6SSricharan R#ifdef __ARMEB__
565f52bb722SSricharan R#define LOW_OFFSET	0x4
566f52bb722SSricharan R#define HIGH_OFFSET	0x0
567f52bb722SSricharan R#else
568f52bb722SSricharan R#define LOW_OFFSET	0x0
569f52bb722SSricharan R#define HIGH_OFFSET	0x4
570f52bb722SSricharan R#endif
571f52bb722SSricharan R
572dc21af99SRussell King#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
573dc21af99SRussell King
574dc21af99SRussell King/* __fixup_pv_table - patch the stub instructions with the delta between
575dc21af99SRussell King * PHYS_OFFSET and PAGE_OFFSET, which is assumed to be 16MiB aligned and
576dc21af99SRussell King * can be expressed by an immediate shifter operand. The stub instruction
577dc21af99SRussell King * has a form of '(add|sub) rd, rn, #imm'.
578dc21af99SRussell King */
579dc21af99SRussell King	__HEAD
580dc21af99SRussell King__fixup_pv_table:
581dc21af99SRussell King	adr	r0, 1f
582f52bb722SSricharan R	ldmia	r0, {r3-r7}
583f52bb722SSricharan R	mvn	ip, #0
584f52bb722SSricharan R	subs	r3, r0, r3	@ PHYS_OFFSET - PAGE_OFFSET
585dc21af99SRussell King	add	r4, r4, r3	@ adjust table start address
586dc21af99SRussell King	add	r5, r5, r3	@ adjust table end address
587f52bb722SSricharan R	add	r6, r6, r3	@ adjust __pv_phys_offset address
588f52bb722SSricharan R	add	r7, r7, r3	@ adjust __pv_offset address
589f52bb722SSricharan R	str	r8, [r6, #LOW_OFFSET]	@ save computed PHYS_OFFSET to __pv_phys_offset
590f52bb722SSricharan R	strcc	ip, [r7, #HIGH_OFFSET]	@ save to __pv_offset high bits
591dc21af99SRussell King	mov	r6, r3, lsr #24	@ constant for add/sub instructions
592dc21af99SRussell King	teq	r3, r6, lsl #24 @ must be 16MiB aligned
593b511d75dSNicolas PitreTHUMB(	it	ne		@ cross section branch )
594dc21af99SRussell King	bne	__error
595f52bb722SSricharan R	str	r3, [r7, #LOW_OFFSET]	@ save to __pv_offset low bits
596dc21af99SRussell King	b	__fixup_a_pv_table
597dc21af99SRussell KingENDPROC(__fixup_pv_table)
598dc21af99SRussell King
599dc21af99SRussell King	.align
600dc21af99SRussell King1:	.long	.
601dc21af99SRussell King	.long	__pv_table_begin
602dc21af99SRussell King	.long	__pv_table_end
603dc21af99SRussell King2:	.long	__pv_phys_offset
604f52bb722SSricharan R	.long	__pv_offset
605dc21af99SRussell King
606dc21af99SRussell King	.text
607dc21af99SRussell King__fixup_a_pv_table:
608f52bb722SSricharan R	adr	r0, 3f
609f52bb722SSricharan R	ldr	r6, [r0]
610f52bb722SSricharan R	add	r6, r6, r3
611f52bb722SSricharan R	ldr	r0, [r6, #HIGH_OFFSET]	@ pv_offset high word
612f52bb722SSricharan R	ldr	r6, [r6, #LOW_OFFSET]	@ pv_offset low word
613f52bb722SSricharan R	mov	r6, r6, lsr #24
614f52bb722SSricharan R	cmn	r0, #1
615b511d75dSNicolas Pitre#ifdef CONFIG_THUMB2_KERNEL
616f52bb722SSricharan R	moveq	r0, #0x200000	@ set bit 21, mov to mvn instruction
617daece596SNicolas Pitre	lsls	r6, #24
618daece596SNicolas Pitre	beq	2f
619b511d75dSNicolas Pitre	clz	r7, r6
620b511d75dSNicolas Pitre	lsr	r6, #24
621b511d75dSNicolas Pitre	lsl	r6, r7
622b511d75dSNicolas Pitre	bic	r6, #0x0080
623b511d75dSNicolas Pitre	lsrs	r7, #1
624b511d75dSNicolas Pitre	orrcs	r6, #0x0080
625b511d75dSNicolas Pitre	orr	r6, r6, r7, lsl #12
626b511d75dSNicolas Pitre	orr	r6, #0x4000
627daece596SNicolas Pitre	b	2f
628daece596SNicolas Pitre1:	add     r7, r3
629daece596SNicolas Pitre	ldrh	ip, [r7, #2]
6302f9bf9beSBen DooksARM_BE8(rev16	ip, ip)
631f52bb722SSricharan R	tst	ip, #0x4000
632f52bb722SSricharan R	and	ip, #0x8f00
633f52bb722SSricharan R	orrne	ip, r6	@ mask in offset bits 31-24
634f52bb722SSricharan R	orreq	ip, r0	@ mask in offset bits 7-0
6352f9bf9beSBen DooksARM_BE8(rev16	ip, ip)
636b511d75dSNicolas Pitre	strh	ip, [r7, #2]
6372098990eSRussell King	bne	2f
6382098990eSRussell King	ldrh	ip, [r7]
6392098990eSRussell KingARM_BE8(rev16	ip, ip)
6402098990eSRussell King	bic	ip, #0x20
6412098990eSRussell King	orr	ip, ip, r0, lsr #16
6422098990eSRussell KingARM_BE8(rev16	ip, ip)
6432098990eSRussell King	strh	ip, [r7]
644daece596SNicolas Pitre2:	cmp	r4, r5
645b511d75dSNicolas Pitre	ldrcc	r7, [r4], #4	@ use branch for delay slot
646daece596SNicolas Pitre	bcc	1b
647b511d75dSNicolas Pitre	bx	lr
648b511d75dSNicolas Pitre#else
649d9a790dfSVictor Kamensky#ifdef CONFIG_CPU_ENDIAN_BE8
650d9a790dfSVictor Kamensky	moveq	r0, #0x00004000	@ set bit 22, mov to mvn instruction
651d9a790dfSVictor Kamensky#else
652f52bb722SSricharan R	moveq	r0, #0x400000	@ set bit 22, mov to mvn instruction
653d9a790dfSVictor Kamensky#endif
654daece596SNicolas Pitre	b	2f
655daece596SNicolas Pitre1:	ldr	ip, [r7, r3]
6562f9bf9beSBen Dooks#ifdef CONFIG_CPU_ENDIAN_BE8
6572f9bf9beSBen Dooks	@ in BE8, we load data in BE, but instructions still in LE
6582f9bf9beSBen Dooks	bic	ip, ip, #0xff000000
6592098990eSRussell King	tst	ip, #0x000f0000	@ check the rotation field
6602098990eSRussell King	orrne	ip, ip, r6, lsl #24 @ mask in offset bits 31-24
6612098990eSRussell King	biceq	ip, ip, #0x00004000 @ clear bit 22
662d9a790dfSVictor Kamensky	orreq	ip, ip, r0      @ mask in offset bits 7-0
6632f9bf9beSBen Dooks#else
664dc21af99SRussell King	bic	ip, ip, #0x000000ff
665f52bb722SSricharan R	tst	ip, #0xf00	@ check the rotation field
666f52bb722SSricharan R	orrne	ip, ip, r6	@ mask in offset bits 31-24
667f52bb722SSricharan R	biceq	ip, ip, #0x400000	@ clear bit 22
668f52bb722SSricharan R	orreq	ip, ip, r0	@ mask in offset bits 7-0
6692f9bf9beSBen Dooks#endif
670dc21af99SRussell King	str	ip, [r7, r3]
671daece596SNicolas Pitre2:	cmp	r4, r5
672dc21af99SRussell King	ldrcc	r7, [r4], #4	@ use branch for delay slot
673daece596SNicolas Pitre	bcc	1b
674dc21af99SRussell King	mov	pc, lr
675b511d75dSNicolas Pitre#endif
676dc21af99SRussell KingENDPROC(__fixup_a_pv_table)
677dc21af99SRussell King
678830fd4d6SSricharan R	.align
679f52bb722SSricharan R3:	.long __pv_offset
680f52bb722SSricharan R
681dc21af99SRussell KingENTRY(fixup_pv_table)
682dc21af99SRussell King	stmfd	sp!, {r4 - r7, lr}
683dc21af99SRussell King	mov	r3, #0			@ no offset
684dc21af99SRussell King	mov	r4, r0			@ r0 = table start
685dc21af99SRussell King	add	r5, r0, r1		@ r1 = table size
686dc21af99SRussell King	bl	__fixup_a_pv_table
687dc21af99SRussell King	ldmfd	sp!, {r4 - r7, pc}
688dc21af99SRussell KingENDPROC(fixup_pv_table)
689dc21af99SRussell King
690dc21af99SRussell King	.data
691dc21af99SRussell King	.globl	__pv_phys_offset
692dc21af99SRussell King	.type	__pv_phys_offset, %object
693dc21af99SRussell King__pv_phys_offset:
694f52bb722SSricharan R	.quad	0
695dc21af99SRussell King	.size	__pv_phys_offset, . -__pv_phys_offset
696f52bb722SSricharan R
697f52bb722SSricharan R	.globl	__pv_offset
698f52bb722SSricharan R	.type	__pv_offset, %object
699dc21af99SRussell King__pv_offset:
700f52bb722SSricharan R	.quad	0
701f52bb722SSricharan R	.size	__pv_offset, . -__pv_offset
702dc21af99SRussell King#endif
703dc21af99SRussell King
70475d90832SHyok S. Choi#include "head-common.S"
705