linux/arch/arm/mm/proc-sa110.S
Russell King 8799ee9f49 [ARM] Set bit 4 on section mappings correctly depending on CPU
On some CPUs, bit 4 of section mappings means "update the
cache when written to".  On others, this bit is required to
be one, and others it's required to be zero.  Finally, on
ARMv6 and above, setting it turns on "no execute" and prevents
speculative prefetches.

With all these combinations, no one value fits all CPUs, so we
have to pick a value depending on the CPU type, and the area
we're mapping.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-29 18:24:21 +01:00

271 lines
6.2 KiB
ArmAsm

/*
* linux/arch/arm/mm/proc-sa110.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-110.
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/procinfo.h>
#include <asm/hardware.h>
#include <asm/pgtable-hwdef.h>
#include <asm/pgtable.h>
#include <asm/ptrace.h>
/*
* the cache line size of the I and D cache
*/
#define DCACHELINESIZE 32
.text
/*
* cpu_sa110_proc_init()
*/
ENTRY(cpu_sa110_proc_init)
mov r0, #0
mcr p15, 0, r0, c15, c1, 2 @ Enable clock switching
mov pc, lr
/*
* cpu_sa110_proc_fin()
*/
ENTRY(cpu_sa110_proc_fin)
stmfd sp!, {lr}
mov ip, #PSR_F_BIT | PSR_I_BIT | SVC_MODE
msr cpsr_c, ip
bl v4wb_flush_kern_cache_all @ clean caches
1: mov r0, #0
mcr p15, 0, r0, 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
ldmfd sp!, {pc}
/*
* cpu_sa110_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
ENTRY(cpu_sa110_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
mov pc, r0
/*
* cpu_sa110_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_sa110_do_idle)
mcr p15, 0, ip, c15, c2, 2 @ disable clock switching
ldr r1, =UNCACHEABLE_ADDR @ load from uncacheable loc
ldr r1, [r1, #0] @ force switch to MCLK
mov r0, r0 @ safety
mov r0, r0 @ safety
mov r0, r0 @ safety
mcr p15, 0, r0, c15, c8, 2 @ Wait for interrupt, cache aligned
mov r0, r0 @ safety
mov r0, r0 @ safety
mov r0, r0 @ safety
mcr p15, 0, r0, c15, c1, 2 @ enable clock switching
mov pc, lr
/* ================================= CACHE ================================ */
/*
* cpu_sa110_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_sa110_dcache_clean_area)
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
add r0, r0, #DCACHELINESIZE
subs r1, r1, #DCACHELINESIZE
bhi 1b
mov pc, lr
/* =============================== PageTable ============================== */
/*
* cpu_sa110_switch_mm(pgd)
*
* Set the translation base pointer to be as described by pgd.
*
* pgd: new page tables
*/
.align 5
ENTRY(cpu_sa110_switch_mm)
#ifdef CONFIG_MMU
str lr, [sp, #-4]!
bl v4wb_flush_kern_cache_all @ clears IP
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
mov pc, lr
#endif
/*
* cpu_sa110_set_pte(ptep, pte)
*
* Set a PTE and flush it out
*/
.align 5
ENTRY(cpu_sa110_set_pte)
#ifdef CONFIG_MMU
str r1, [r0], #-2048 @ linux version
eor r1, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
bic r2, r1, #PTE_SMALL_AP_MASK
bic r2, r2, #PTE_TYPE_MASK
orr r2, r2, #PTE_TYPE_SMALL
tst r1, #L_PTE_USER @ User?
orrne r2, r2, #PTE_SMALL_AP_URO_SRW
tst r1, #L_PTE_WRITE | L_PTE_DIRTY @ Write and Dirty?
orreq r2, r2, #PTE_SMALL_AP_UNO_SRW
tst r1, #L_PTE_PRESENT | L_PTE_YOUNG @ Present and Young?
movne r2, #0
str r2, [r0] @ hardware version
mov r0, r0
mcr p15, 0, r0, c7, c10, 1 @ clean D entry
mcr p15, 0, r0, c7, c10, 4 @ drain WB
#endif
mov pc, lr
__INIT
.type __sa110_setup, #function
__sa110_setup:
mov r10, #0
mcr p15, 0, r10, c7, c7 @ invalidate I,D caches on v4
mcr p15, 0, r10, c7, c10, 4 @ drain write buffer on v4
#ifdef CONFIG_MMU
mcr p15, 0, r10, c8, c7 @ invalidate I,D TLBs on v4
#endif
mrc p15, 0, r0, c1, c0 @ get control register v4
ldr r5, sa110_cr1_clear
bic r0, r0, r5
ldr r5, sa110_cr1_set
orr r0, r0, r5
mov pc, lr
.size __sa110_setup, . - __sa110_setup
/*
* R
* .RVI ZFRS BLDP WCAM
* ..01 0001 ..11 1101
*
*/
.type sa110_cr1_clear, #object
.type sa110_cr1_set, #object
sa110_cr1_clear:
.word 0x3f3f
sa110_cr1_set:
.word 0x113d
__INITDATA
/*
* Purpose : Function pointers used to access above functions - all calls
* come through these
*/
.type sa110_processor_functions, #object
ENTRY(sa110_processor_functions)
.word v4_early_abort
.word cpu_sa110_proc_init
.word cpu_sa110_proc_fin
.word cpu_sa110_reset
.word cpu_sa110_do_idle
.word cpu_sa110_dcache_clean_area
.word cpu_sa110_switch_mm
.word cpu_sa110_set_pte
.size sa110_processor_functions, . - sa110_processor_functions
.section ".rodata"
.type cpu_arch_name, #object
cpu_arch_name:
.asciz "armv4"
.size cpu_arch_name, . - cpu_arch_name
.type cpu_elf_name, #object
cpu_elf_name:
.asciz "v4"
.size cpu_elf_name, . - cpu_elf_name
.type cpu_sa110_name, #object
cpu_sa110_name:
.asciz "StrongARM-110"
.size cpu_sa110_name, . - cpu_sa110_name
.align
.section ".proc.info.init", #alloc, #execinstr
.type __sa110_proc_info,#object
__sa110_proc_info:
.long 0x4401a100
.long 0xfffffff0
.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 __sa110_setup
.long cpu_arch_name
.long cpu_elf_name
.long HWCAP_SWP | HWCAP_HALF | HWCAP_26BIT | HWCAP_FAST_MULT
.long cpu_sa110_name
.long sa110_processor_functions
.long v4wb_tlb_fns
.long v4wb_user_fns
.long v4wb_cache_fns
.size __sa110_proc_info, . - __sa110_proc_info