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linux/arch/arm/mm/pv-fixup-asm.S

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-04 10:11:33 +02:00
/* SPDX-License-Identifier: GPL-2.0-only */
ARM: re-implement physical address space switching Re-implement the physical address space switching to be architecturally compliant. This involves flushing the caches, disabling the MMU, and only then updating the page tables. Once that is complete, the system can be brought back up again. Since we disable the MMU, we need to do the update in assembly code. Luckily, the entries which need updating are fairly trivial, and are all setup by the early assembly code. We can merely adjust each entry by the delta required. Not only does this fix the code to be architecturally compliant, but it fixes a couple of bugs too: 1. The original code would only ever update the first L2 entry covering a fraction of the kernel; the remainder were left untouched. 2. The L2 entries covering the DTB blob were likewise untouched. This solution fixes up all entries. Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-04 16:58:38 +01:00
/*
* Copyright (C) 2015 Russell King
*
* This assembly is required to safely remap the physical address space
* for Keystone 2
*/
#include <linux/linkage.h>
#include <asm/asm-offsets.h>
#include <asm/cp15.h>
#include <asm/memory.h>
#include <asm/pgtable.h>
.section ".idmap.text", "ax"
#define L1_ORDER 3
#define L2_ORDER 3
ENTRY(lpae_pgtables_remap_asm)
stmfd sp!, {r4-r8, lr}
mrc p15, 0, r8, c1, c0, 0 @ read control reg
bic ip, r8, #CR_M @ disable caches and MMU
mcr p15, 0, ip, c1, c0, 0
dsb
isb
/* Update level 2 entries covering the kernel */
ldr r6, =(_end - 1)
add r7, r2, #0x1000
add r6, r7, r6, lsr #SECTION_SHIFT - L2_ORDER
add r7, r7, #PAGE_OFFSET >> (SECTION_SHIFT - L2_ORDER)
ARM: 8811/1: always list both ldrd/strd registers explicitly The ldrd and strd instructions work on a pair of consecutive registers. It is possible to specify either the first register in the pair, or both registers explicitly. Let's always do the later to make things clearer. Signed-off-by: Nicolas Pitre <nico@linaro.org> Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-11-09 04:26:39 +01:00
1: ldrd r4, r5, [r7]
ARM: re-implement physical address space switching Re-implement the physical address space switching to be architecturally compliant. This involves flushing the caches, disabling the MMU, and only then updating the page tables. Once that is complete, the system can be brought back up again. Since we disable the MMU, we need to do the update in assembly code. Luckily, the entries which need updating are fairly trivial, and are all setup by the early assembly code. We can merely adjust each entry by the delta required. Not only does this fix the code to be architecturally compliant, but it fixes a couple of bugs too: 1. The original code would only ever update the first L2 entry covering a fraction of the kernel; the remainder were left untouched. 2. The L2 entries covering the DTB blob were likewise untouched. This solution fixes up all entries. Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-04 16:58:38 +01:00
adds r4, r4, r0
adc r5, r5, r1
ARM: 8811/1: always list both ldrd/strd registers explicitly The ldrd and strd instructions work on a pair of consecutive registers. It is possible to specify either the first register in the pair, or both registers explicitly. Let's always do the later to make things clearer. Signed-off-by: Nicolas Pitre <nico@linaro.org> Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-11-09 04:26:39 +01:00
strd r4, r5, [r7], #1 << L2_ORDER
ARM: re-implement physical address space switching Re-implement the physical address space switching to be architecturally compliant. This involves flushing the caches, disabling the MMU, and only then updating the page tables. Once that is complete, the system can be brought back up again. Since we disable the MMU, we need to do the update in assembly code. Luckily, the entries which need updating are fairly trivial, and are all setup by the early assembly code. We can merely adjust each entry by the delta required. Not only does this fix the code to be architecturally compliant, but it fixes a couple of bugs too: 1. The original code would only ever update the first L2 entry covering a fraction of the kernel; the remainder were left untouched. 2. The L2 entries covering the DTB blob were likewise untouched. This solution fixes up all entries. Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-04 16:58:38 +01:00
cmp r7, r6
bls 1b
/* Update level 2 entries for the boot data */
add r7, r2, #0x1000
add r7, r7, r3, lsr #SECTION_SHIFT - L2_ORDER
bic r7, r7, #(1 << L2_ORDER) - 1
ARM: 8811/1: always list both ldrd/strd registers explicitly The ldrd and strd instructions work on a pair of consecutive registers. It is possible to specify either the first register in the pair, or both registers explicitly. Let's always do the later to make things clearer. Signed-off-by: Nicolas Pitre <nico@linaro.org> Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-11-09 04:26:39 +01:00
ldrd r4, r5, [r7]
ARM: re-implement physical address space switching Re-implement the physical address space switching to be architecturally compliant. This involves flushing the caches, disabling the MMU, and only then updating the page tables. Once that is complete, the system can be brought back up again. Since we disable the MMU, we need to do the update in assembly code. Luckily, the entries which need updating are fairly trivial, and are all setup by the early assembly code. We can merely adjust each entry by the delta required. Not only does this fix the code to be architecturally compliant, but it fixes a couple of bugs too: 1. The original code would only ever update the first L2 entry covering a fraction of the kernel; the remainder were left untouched. 2. The L2 entries covering the DTB blob were likewise untouched. This solution fixes up all entries. Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-04 16:58:38 +01:00
adds r4, r4, r0
adc r5, r5, r1
ARM: 8811/1: always list both ldrd/strd registers explicitly The ldrd and strd instructions work on a pair of consecutive registers. It is possible to specify either the first register in the pair, or both registers explicitly. Let's always do the later to make things clearer. Signed-off-by: Nicolas Pitre <nico@linaro.org> Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-11-09 04:26:39 +01:00
strd r4, r5, [r7], #1 << L2_ORDER
ldrd r4, r5, [r7]
ARM: re-implement physical address space switching Re-implement the physical address space switching to be architecturally compliant. This involves flushing the caches, disabling the MMU, and only then updating the page tables. Once that is complete, the system can be brought back up again. Since we disable the MMU, we need to do the update in assembly code. Luckily, the entries which need updating are fairly trivial, and are all setup by the early assembly code. We can merely adjust each entry by the delta required. Not only does this fix the code to be architecturally compliant, but it fixes a couple of bugs too: 1. The original code would only ever update the first L2 entry covering a fraction of the kernel; the remainder were left untouched. 2. The L2 entries covering the DTB blob were likewise untouched. This solution fixes up all entries. Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-04 16:58:38 +01:00
adds r4, r4, r0
adc r5, r5, r1
ARM: 8811/1: always list both ldrd/strd registers explicitly The ldrd and strd instructions work on a pair of consecutive registers. It is possible to specify either the first register in the pair, or both registers explicitly. Let's always do the later to make things clearer. Signed-off-by: Nicolas Pitre <nico@linaro.org> Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-11-09 04:26:39 +01:00
strd r4, r5, [r7]
ARM: re-implement physical address space switching Re-implement the physical address space switching to be architecturally compliant. This involves flushing the caches, disabling the MMU, and only then updating the page tables. Once that is complete, the system can be brought back up again. Since we disable the MMU, we need to do the update in assembly code. Luckily, the entries which need updating are fairly trivial, and are all setup by the early assembly code. We can merely adjust each entry by the delta required. Not only does this fix the code to be architecturally compliant, but it fixes a couple of bugs too: 1. The original code would only ever update the first L2 entry covering a fraction of the kernel; the remainder were left untouched. 2. The L2 entries covering the DTB blob were likewise untouched. This solution fixes up all entries. Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-04 16:58:38 +01:00
/* Update level 1 entries */
mov r6, #4
mov r7, r2
ARM: 8811/1: always list both ldrd/strd registers explicitly The ldrd and strd instructions work on a pair of consecutive registers. It is possible to specify either the first register in the pair, or both registers explicitly. Let's always do the later to make things clearer. Signed-off-by: Nicolas Pitre <nico@linaro.org> Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-11-09 04:26:39 +01:00
2: ldrd r4, r5, [r7]
ARM: re-implement physical address space switching Re-implement the physical address space switching to be architecturally compliant. This involves flushing the caches, disabling the MMU, and only then updating the page tables. Once that is complete, the system can be brought back up again. Since we disable the MMU, we need to do the update in assembly code. Luckily, the entries which need updating are fairly trivial, and are all setup by the early assembly code. We can merely adjust each entry by the delta required. Not only does this fix the code to be architecturally compliant, but it fixes a couple of bugs too: 1. The original code would only ever update the first L2 entry covering a fraction of the kernel; the remainder were left untouched. 2. The L2 entries covering the DTB blob were likewise untouched. This solution fixes up all entries. Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-04 16:58:38 +01:00
adds r4, r4, r0
adc r5, r5, r1
ARM: 8811/1: always list both ldrd/strd registers explicitly The ldrd and strd instructions work on a pair of consecutive registers. It is possible to specify either the first register in the pair, or both registers explicitly. Let's always do the later to make things clearer. Signed-off-by: Nicolas Pitre <nico@linaro.org> Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-11-09 04:26:39 +01:00
strd r4, r5, [r7], #1 << L1_ORDER
ARM: re-implement physical address space switching Re-implement the physical address space switching to be architecturally compliant. This involves flushing the caches, disabling the MMU, and only then updating the page tables. Once that is complete, the system can be brought back up again. Since we disable the MMU, we need to do the update in assembly code. Luckily, the entries which need updating are fairly trivial, and are all setup by the early assembly code. We can merely adjust each entry by the delta required. Not only does this fix the code to be architecturally compliant, but it fixes a couple of bugs too: 1. The original code would only ever update the first L2 entry covering a fraction of the kernel; the remainder were left untouched. 2. The L2 entries covering the DTB blob were likewise untouched. This solution fixes up all entries. Tested-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-04-04 16:58:38 +01:00
subs r6, r6, #1
bne 2b
mrrc p15, 0, r4, r5, c2 @ read TTBR0
adds r4, r4, r0 @ update physical address
adc r5, r5, r1
mcrr p15, 0, r4, r5, c2 @ write back TTBR0
mrrc p15, 1, r4, r5, c2 @ read TTBR1
adds r4, r4, r0 @ update physical address
adc r5, r5, r1
mcrr p15, 1, r4, r5, c2 @ write back TTBR1
dsb
mov ip, #0
mcr p15, 0, ip, c7, c5, 0 @ I+BTB cache invalidate
mcr p15, 0, ip, c8, c7, 0 @ local_flush_tlb_all()
dsb
isb
mcr p15, 0, r8, c1, c0, 0 @ re-enable MMU
dsb
isb
ldmfd sp!, {r4-r8, pc}
ENDPROC(lpae_pgtables_remap_asm)
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