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linux/arch/arm/lib/io-readsw-armv3.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 16:11:33 +08:00
/* SPDX-License-Identifier: GPL-2.0-only */
ARM: Bring back ARMv3 IO and user access code This partially reverts 357c9c1f07d4546bc3fbc0fd1044d96b114d14ed (ARM: Remove support for ARMv3 ARM610 and ARM710 CPUs). Although we only support StrongARM on the RiscPC, we need to keep the ARMv3 user access code for this platform because the bus does not understand half-word load/stores. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-08-13 18:44:13 +08:00
/*
* linux/arch/arm/lib/io-readsw-armv3.S
*
* Copyright (C) 1995-2000 Russell King
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
.Linsw_bad_alignment:
adr r0, .Linsw_bad_align_msg
mov r2, lr
b panic
.Linsw_bad_align_msg:
.asciz "insw: bad buffer alignment (0x%p, lr=0x%08lX)\n"
.align
.Linsw_align: tst r1, #1
bne .Linsw_bad_alignment
ldr r3, [r0]
strb r3, [r1], #1
mov r3, r3, lsr #8
strb r3, [r1], #1
subs r2, r2, #1
ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ ARMv6 and greater introduced a new instruction ("bx") which can be used to return from function calls. Recent CPUs perform better when the "bx lr" instruction is used rather than the "mov pc, lr" instruction, and this sequence is strongly recommended to be used by the ARM architecture manual (section A.4.1.1). We provide a new macro "ret" with all its variants for the condition code which will resolve to the appropriate instruction. Rather than doing this piecemeal, and miss some instances, change all the "mov pc" instances to use the new macro, with the exception of the "movs" instruction and the kprobes code. This allows us to detect the "mov pc, lr" case and fix it up - and also gives us the possibility of deploying this for other registers depending on the CPU selection. Reported-by: Will Deacon <will.deacon@arm.com> Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1 Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood Tested-by: Shawn Guo <shawn.guo@freescale.com> Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385 Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-06-30 23:29:12 +08:00
reteq lr
ARM: Bring back ARMv3 IO and user access code This partially reverts 357c9c1f07d4546bc3fbc0fd1044d96b114d14ed (ARM: Remove support for ARMv3 ARM610 and ARM710 CPUs). Although we only support StrongARM on the RiscPC, we need to keep the ARMv3 user access code for this platform because the bus does not understand half-word load/stores. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-08-13 18:44:13 +08:00
ENTRY(__raw_readsw)
teq r2, #0 @ do we have to check for the zero len?
ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ ARMv6 and greater introduced a new instruction ("bx") which can be used to return from function calls. Recent CPUs perform better when the "bx lr" instruction is used rather than the "mov pc, lr" instruction, and this sequence is strongly recommended to be used by the ARM architecture manual (section A.4.1.1). We provide a new macro "ret" with all its variants for the condition code which will resolve to the appropriate instruction. Rather than doing this piecemeal, and miss some instances, change all the "mov pc" instances to use the new macro, with the exception of the "movs" instruction and the kprobes code. This allows us to detect the "mov pc, lr" case and fix it up - and also gives us the possibility of deploying this for other registers depending on the CPU selection. Reported-by: Will Deacon <will.deacon@arm.com> Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1 Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood Tested-by: Shawn Guo <shawn.guo@freescale.com> Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385 Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-06-30 23:29:12 +08:00
reteq lr
ARM: Bring back ARMv3 IO and user access code This partially reverts 357c9c1f07d4546bc3fbc0fd1044d96b114d14ed (ARM: Remove support for ARMv3 ARM610 and ARM710 CPUs). Although we only support StrongARM on the RiscPC, we need to keep the ARMv3 user access code for this platform because the bus does not understand half-word load/stores. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-08-13 18:44:13 +08:00
tst r1, #3
bne .Linsw_align
.Linsw_aligned: mov ip, #0xff
orr ip, ip, ip, lsl #8
stmfd sp!, {r4, r5, r6, lr}
subs r2, r2, #8
bmi .Lno_insw_8
.Linsw_8_lp: ldr r3, [r0]
and r3, r3, ip
ldr r4, [r0]
orr r3, r3, r4, lsl #16
ldr r4, [r0]
and r4, r4, ip
ldr r5, [r0]
orr r4, r4, r5, lsl #16
ldr r5, [r0]
and r5, r5, ip
ldr r6, [r0]
orr r5, r5, r6, lsl #16
ldr r6, [r0]
and r6, r6, ip
ldr lr, [r0]
orr r6, r6, lr, lsl #16
stmia r1!, {r3 - r6}
subs r2, r2, #8
bpl .Linsw_8_lp
tst r2, #7
ARM: 8844/1: use unified assembler in assembly files Use unified assembler syntax (UAL) in assembly files. Divided syntax is considered deprecated. This will also allow to build the kernel using LLVM's integrated assembler. Signed-off-by: Stefan Agner <stefan@agner.ch> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-02-18 07:57:38 +08:00
ldmfdeq sp!, {r4, r5, r6, pc}
ARM: Bring back ARMv3 IO and user access code This partially reverts 357c9c1f07d4546bc3fbc0fd1044d96b114d14ed (ARM: Remove support for ARMv3 ARM610 and ARM710 CPUs). Although we only support StrongARM on the RiscPC, we need to keep the ARMv3 user access code for this platform because the bus does not understand half-word load/stores. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-08-13 18:44:13 +08:00
.Lno_insw_8: tst r2, #4
beq .Lno_insw_4
ldr r3, [r0]
and r3, r3, ip
ldr r4, [r0]
orr r3, r3, r4, lsl #16
ldr r4, [r0]
and r4, r4, ip
ldr r5, [r0]
orr r4, r4, r5, lsl #16
stmia r1!, {r3, r4}
.Lno_insw_4: tst r2, #2
beq .Lno_insw_2
ldr r3, [r0]
and r3, r3, ip
ldr r4, [r0]
orr r3, r3, r4, lsl #16
str r3, [r1], #4
.Lno_insw_2: tst r2, #1
ldrne r3, [r0]
ARM: 8844/1: use unified assembler in assembly files Use unified assembler syntax (UAL) in assembly files. Divided syntax is considered deprecated. This will also allow to build the kernel using LLVM's integrated assembler. Signed-off-by: Stefan Agner <stefan@agner.ch> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-02-18 07:57:38 +08:00
strbne r3, [r1], #1
ARM: Bring back ARMv3 IO and user access code This partially reverts 357c9c1f07d4546bc3fbc0fd1044d96b114d14ed (ARM: Remove support for ARMv3 ARM610 and ARM710 CPUs). Although we only support StrongARM on the RiscPC, we need to keep the ARMv3 user access code for this platform because the bus does not understand half-word load/stores. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-08-13 18:44:13 +08:00
movne r3, r3, lsr #8
ARM: 8844/1: use unified assembler in assembly files Use unified assembler syntax (UAL) in assembly files. Divided syntax is considered deprecated. This will also allow to build the kernel using LLVM's integrated assembler. Signed-off-by: Stefan Agner <stefan@agner.ch> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2019-02-18 07:57:38 +08:00
strbne r3, [r1]
ARM: Bring back ARMv3 IO and user access code This partially reverts 357c9c1f07d4546bc3fbc0fd1044d96b114d14ed (ARM: Remove support for ARMv3 ARM610 and ARM710 CPUs). Although we only support StrongARM on the RiscPC, we need to keep the ARMv3 user access code for this platform because the bus does not understand half-word load/stores. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-08-13 18:44:13 +08:00
ldmfd sp!, {r4, r5, r6, pc}
Revert "arm: move exports to definitions" This reverts commit 4dd1837d7589f468ed109556513f476e7a7f9121. Moving the exports for assembly code into the assembly files breaks KSYM trimming, but also breaks modversions. While fixing the KSYM trimming is trivial, fixing modversions brings us to a technically worse position that we had prior to the above change: - We end up with the prototype definitions divorsed from everything else, which means that adding or removing assembly level ksyms become more fragile: * if adding a new assembly ksyms export, a missed prototype in asm-prototypes.h results in a successful build if no module in the selected configuration makes use of the symbol. * when removing a ksyms export, asm-prototypes.h will get forgotten, with armksyms.c, you'll get a build error if you forget to touch the file. - We end up with the same amount of include files and prototypes, they're just in a header file instead of a .c file with their exports. As for lines of code, we don't get much of a size reduction: (original commit) 47 files changed, 131 insertions(+), 208 deletions(-) (fix for ksyms trimming) 7 files changed, 18 insertions(+), 5 deletions(-) (two fixes for modversions) 1 file changed, 34 insertions(+) 3 files changed, 7 insertions(+), 2 deletions(-) which results in a net total of only 25 lines deleted. As there does not seem to be much benefit from this change of approach, revert the change. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2016-11-23 18:00:03 +08:00