kernel-ark/arch/arm/mm/proc-sa1100.S
Russell King 6ebbf2ce43 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>
2014-07-18 12:29:04 +01:00

274 lines
6.8 KiB
ArmAsm

/*
* linux/arch/arm/mm/proc-sa1100.S
*
* Copyright (C) 1997-2002 Russell King
* hacked for non-paged-MM by Hyok S. Choi, 2003.
*
* 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.
*
* MMU functions for SA110
*
* These are the low level assembler for performing cache and TLB
* functions on the StrongARM-1100 and StrongARM-1110.
*
* Note that SA1100 and SA1110 share everything but their name and CPU ID.
*
* 12-jun-2000, Erik Mouw (J.A.K.Mouw@its.tudelft.nl):
* Flush the read buffer at context switches
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/hwcap.h>
#include <mach/hardware.h>
#include <asm/pgtable-hwdef.h>
#include <asm/pgtable.h>
#include "proc-macros.S"
/*
* the cache line size of the I and D cache
*/
#define DCACHELINESIZE 32
.section .text
/*
* cpu_sa1100_proc_init()
*/
ENTRY(cpu_sa1100_proc_init)
mov r0, #0
mcr p15, 0, r0, c15, c1, 2 @ Enable clock switching
mcr p15, 0, r0, c9, c0, 5 @ Allow read-buffer operations from userland
ret lr
/*
* cpu_sa1100_proc_fin()
*
* Prepare the CPU for reset:
* - Disable interrupts
* - Clean and turn off caches.
*/
ENTRY(cpu_sa1100_proc_fin)
mcr p15, 0, ip, c15, c2, 2 @ Disable clock switching
mrc p15, 0, r0, c1, c0, 0 @ ctrl register
bic r0, r0, #0x1000 @ ...i............
bic r0, r0, #0x000e @ ............wca.
mcr p15, 0, r0, c1, c0, 0 @ disable caches
ret lr
/*
* cpu_sa1100_reset(loc)
*
* Perform a soft reset of the system. Put the CPU into the
* same state as it would be if it had been reset, and branch
* to what would be the reset vector.
*
* loc: location to jump to for soft reset
*/
.align 5
.pushsection .idmap.text, "ax"
ENTRY(cpu_sa1100_reset)
mov ip, #0
mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
mcr p15, 0, ip, c7, c10, 4 @ drain WB
#ifdef CONFIG_MMU
mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
#endif
mrc p15, 0, ip, c1, c0, 0 @ ctrl register
bic ip, ip, #0x000f @ ............wcam
bic ip, ip, #0x1100 @ ...i...s........
mcr p15, 0, ip, c1, c0, 0 @ ctrl register
ret r0
ENDPROC(cpu_sa1100_reset)
.popsection
/*
* cpu_sa1100_do_idle(type)
*
* Cause the processor to idle
*
* type: call type:
* 0 = slow idle
* 1 = fast idle
* 2 = switch to slow processor clock
* 3 = switch to fast processor clock
*/
.align 5
ENTRY(cpu_sa1100_do_idle)
mov r0, r0 @ 4 nop padding
mov r0, r0
mov r0, r0
mov r0, r0 @ 4 nop padding
mov r0, r0
mov r0, r0
mov r0, #0
ldr r1, =UNCACHEABLE_ADDR @ ptr to uncacheable address
@ --- aligned to a cache line
mcr p15, 0, r0, c15, c2, 2 @ disable clock switching
ldr r1, [r1, #0] @ force switch to MCLK
mcr p15, 0, r0, c15, c8, 2 @ wait for interrupt
mov r0, r0 @ safety
mcr p15, 0, r0, c15, c1, 2 @ enable clock switching
ret lr
/* ================================= CACHE ================================ */
/*
* cpu_sa1100_dcache_clean_area(addr,sz)
*
* Clean the specified entry of any caches such that the MMU
* translation fetches will obtain correct data.
*
* addr: cache-unaligned virtual address
*/
.align 5
ENTRY(cpu_sa1100_dcache_clean_area)
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
add r0, r0, #DCACHELINESIZE
subs r1, r1, #DCACHELINESIZE
bhi 1b
ret lr
/* =============================== PageTable ============================== */
/*
* cpu_sa1100_switch_mm(pgd)
*
* Set the translation base pointer to be as described by pgd.
*
* pgd: new page tables
*/
.align 5
ENTRY(cpu_sa1100_switch_mm)
#ifdef CONFIG_MMU
str lr, [sp, #-4]!
bl v4wb_flush_kern_cache_all @ clears IP
mcr p15, 0, ip, c9, c0, 0 @ invalidate RB
mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
ldr pc, [sp], #4
#else
ret lr
#endif
/*
* cpu_sa1100_set_pte_ext(ptep, pte, ext)
*
* Set a PTE and flush it out
*/
.align 5
ENTRY(cpu_sa1100_set_pte_ext)
#ifdef CONFIG_MMU
armv3_set_pte_ext wc_disable=0
mov r0, r0
mcr p15, 0, r0, c7, c10, 1 @ clean D entry
mcr p15, 0, r0, c7, c10, 4 @ drain WB
#endif
ret lr
.globl cpu_sa1100_suspend_size
.equ cpu_sa1100_suspend_size, 4 * 3
#ifdef CONFIG_ARM_CPU_SUSPEND
ENTRY(cpu_sa1100_do_suspend)
stmfd sp!, {r4 - r6, lr}
mrc p15, 0, r4, c3, c0, 0 @ domain ID
mrc p15, 0, r5, c13, c0, 0 @ PID
mrc p15, 0, r6, c1, c0, 0 @ control reg
stmia r0, {r4 - r6} @ store cp regs
ldmfd sp!, {r4 - r6, pc}
ENDPROC(cpu_sa1100_do_suspend)
ENTRY(cpu_sa1100_do_resume)
ldmia r0, {r4 - r6} @ load cp regs
mov ip, #0
mcr p15, 0, ip, c8, c7, 0 @ flush I+D TLBs
mcr p15, 0, ip, c7, c7, 0 @ flush I&D cache
mcr p15, 0, ip, c9, c0, 0 @ invalidate RB
mcr p15, 0, ip, c9, c0, 5 @ allow user space to use RB
mcr p15, 0, r4, c3, c0, 0 @ domain ID
mcr p15, 0, r1, c2, c0, 0 @ translation table base addr
mcr p15, 0, r5, c13, c0, 0 @ PID
mov r0, r6 @ control register
b cpu_resume_mmu
ENDPROC(cpu_sa1100_do_resume)
#endif
.type __sa1100_setup, #function
__sa1100_setup:
mov r0, #0
mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
#ifdef CONFIG_MMU
mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
#endif
adr r5, sa1100_crval
ldmia r5, {r5, r6}
mrc p15, 0, r0, c1, c0 @ get control register v4
bic r0, r0, r5
orr r0, r0, r6
ret lr
.size __sa1100_setup, . - __sa1100_setup
/*
* R
* .RVI ZFRS BLDP WCAM
* ..11 0001 ..11 1101
*
*/
.type sa1100_crval, #object
sa1100_crval:
crval clear=0x00003f3f, mmuset=0x0000313d, ucset=0x00001130
__INITDATA
/*
* SA1100 and SA1110 share the same function calls
*/
@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
define_processor_functions sa1100, dabort=v4_early_abort, pabort=legacy_pabort, suspend=1
.section ".rodata"
string cpu_arch_name, "armv4"
string cpu_elf_name, "v4"
string cpu_sa1100_name, "StrongARM-1100"
string cpu_sa1110_name, "StrongARM-1110"
.align
.section ".proc.info.init", #alloc, #execinstr
.macro sa1100_proc_info name:req, cpu_val:req, cpu_mask:req, cpu_name:req
.type __\name\()_proc_info,#object
__\name\()_proc_info:
.long \cpu_val
.long \cpu_mask
.long PMD_TYPE_SECT | \
PMD_SECT_BUFFERABLE | \
PMD_SECT_CACHEABLE | \
PMD_SECT_AP_WRITE | \
PMD_SECT_AP_READ
.long PMD_TYPE_SECT | \
PMD_SECT_AP_WRITE | \
PMD_SECT_AP_READ
b __sa1100_setup
.long cpu_arch_name
.long cpu_elf_name
.long HWCAP_SWP | HWCAP_HALF | HWCAP_26BIT | HWCAP_FAST_MULT
.long \cpu_name
.long sa1100_processor_functions
.long v4wb_tlb_fns
.long v4_mc_user_fns
.long v4wb_cache_fns
.size __\name\()_proc_info, . - __\name\()_proc_info
.endm
sa1100_proc_info sa1100, 0x4401a110, 0xfffffff0, cpu_sa1100_name
sa1100_proc_info sa1110, 0x6901b110, 0xfffffff0, cpu_sa1110_name