linux/arch/arm/mm/proc-xsc3.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

507 lines
13 KiB
ArmAsm

/*
* linux/arch/arm/mm/proc-xsc3.S
*
* Original Author: Matthew Gilbert
* Current Maintainer: Deepak Saxena <dsaxena@plexity.net>
*
* Copyright 2004 (C) Intel Corp.
* Copyright 2005 (c) MontaVista Software, Inc.
*
* 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 the Intel XScale3 Core (XSC3). The XSC3 core is an
* extension to Intel's original XScale core that adds the following
* features:
*
* - ARMv6 Supersections
* - Low Locality Reference pages (replaces mini-cache)
* - 36-bit addressing
* - L2 cache
* - Cache-coherency if chipset supports it
*
* Based on orignal XScale code by Nicolas Pitre
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/assembler.h>
#include <asm/procinfo.h>
#include <asm/hardware.h>
#include <asm/pgtable.h>
#include <asm/pgtable-hwdef.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include "proc-macros.S"
/*
* This is the maximum size of an area which will be flushed. If the
* area is larger than this, then we flush the whole cache.
*/
#define MAX_AREA_SIZE 32768
/*
* The cache line size of the I and D cache.
*/
#define CACHELINESIZE 32
/*
* The size of the data cache.
*/
#define CACHESIZE 32768
/*
* Run with L2 enabled.
*/
#define L2_CACHE_ENABLE 1
/*
* Enable the Branch Target Buffer (can cause crashes, see erratum #42.)
*/
#define BTB_ENABLE 0
/*
* This macro is used to wait for a CP15 write and is needed
* when we have to ensure that the last operation to the co-pro
* was completed before continuing with operation.
*/
.macro cpwait_ret, lr, rd
mrc p15, 0, \rd, c2, c0, 0 @ arbitrary read of cp15
sub pc, \lr, \rd, LSR #32 @ wait for completion and
@ flush instruction pipeline
.endm
/*
* This macro cleans & invalidates the entire xsc3 dcache by set & way.
*/
.macro clean_d_cache rd, rs
mov \rd, #0x1f00
orr \rd, \rd, #0x00e0
1: mcr p15, 0, \rd, c7, c14, 2 @ clean/inv set/way
adds \rd, \rd, #0x40000000
bcc 1b
subs \rd, \rd, #0x20
bpl 1b
.endm
.text
/*
* cpu_xsc3_proc_init()
*
* Nothing too exciting at the moment
*/
ENTRY(cpu_xsc3_proc_init)
mov pc, lr
/*
* cpu_xsc3_proc_fin()
*/
ENTRY(cpu_xsc3_proc_fin)
str lr, [sp, #-4]!
mov r0, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
msr cpsr_c, r0
bl xsc3_flush_kern_cache_all @ clean caches
mrc p15, 0, r0, c1, c0, 0 @ ctrl register
bic r0, r0, #0x1800 @ ...IZ...........
bic r0, r0, #0x0006 @ .............CA.
mcr p15, 0, r0, c1, c0, 0 @ disable caches
ldr pc, [sp], #4
/*
* cpu_xsc3_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_xsc3_reset)
mov r1, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
msr cpsr_c, r1 @ reset CPSR
mrc p15, 0, r1, c1, c0, 0 @ ctrl register
bic r1, r1, #0x0086 @ ........B....CA.
bic r1, r1, #0x3900 @ ..VIZ..S........
mcr p15, 0, r1, c1, c0, 0 @ ctrl register
mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches & BTB
bic r1, r1, #0x0001 @ ...............M
mcr p15, 0, r1, c1, c0, 0 @ ctrl register
@ CAUTION: MMU turned off from this point. We count on the pipeline
@ already containing those two last instructions to survive.
mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
mov pc, r0
/*
* cpu_xsc3_do_idle()
*
* Cause the processor to idle
*
* For now we do nothing but go to idle mode for every case
*
* XScale supports clock switching, but using idle mode support
* allows external hardware to react to system state changes.
MMG: Come back to this one.
*/
.align 5
ENTRY(cpu_xsc3_do_idle)
mov r0, #1
mcr p14, 0, r0, c7, c0, 0 @ Go to IDLE
mov pc, lr
/* ================================= CACHE ================================ */
/*
* flush_user_cache_all()
*
* Invalidate all cache entries in a particular address
* space.
*/
ENTRY(xsc3_flush_user_cache_all)
/* FALLTHROUGH */
/*
* flush_kern_cache_all()
*
* Clean and invalidate the entire cache.
*/
ENTRY(xsc3_flush_kern_cache_all)
mov r2, #VM_EXEC
mov ip, #0
__flush_whole_cache:
clean_d_cache r0, r1
tst r2, #VM_EXEC
mcrne p15, 0, ip, c7, c5, 0 @ Invalidate I cache & BTB
mcrne p15, 0, ip, c7, c10, 4 @ Drain Write Buffer
mcrne p15, 0, ip, c7, c5, 4 @ Prefetch Flush
mov pc, lr
/*
* flush_user_cache_range(start, end, vm_flags)
*
* Invalidate a range of cache entries in the specified
* address space.
*
* - start - start address (may not be aligned)
* - end - end address (exclusive, may not be aligned)
* - vma - vma_area_struct describing address space
*/
.align 5
ENTRY(xsc3_flush_user_cache_range)
mov ip, #0
sub r3, r1, r0 @ calculate total size
cmp r3, #MAX_AREA_SIZE
bhs __flush_whole_cache
1: tst r2, #VM_EXEC
mcrne p15, 0, r0, c7, c5, 1 @ Invalidate I cache line
mcr p15, 0, r0, c7, c14, 1 @ Clean/invalidate D cache line
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
tst r2, #VM_EXEC
mcrne p15, 0, ip, c7, c5, 6 @ Invalidate BTB
mcrne p15, 0, ip, c7, c10, 4 @ Drain Write Buffer
mcrne p15, 0, ip, c7, c5, 4 @ Prefetch Flush
mov pc, lr
/*
* coherent_kern_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start. If you have non-snooping
* Harvard caches, you need to implement this function.
*
* - start - virtual start address
* - end - virtual end address
*
* Note: single I-cache line invalidation isn't used here since
* it also trashes the mini I-cache used by JTAG debuggers.
*/
ENTRY(xsc3_coherent_kern_range)
/* FALLTHROUGH */
ENTRY(xsc3_coherent_user_range)
bic r0, r0, #CACHELINESIZE - 1
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ Invalidate I cache & BTB
mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer
mcr p15, 0, r0, c7, c5, 4 @ Prefetch Flush
mov pc, lr
/*
* flush_kern_dcache_page(void *page)
*
* Ensure no D cache aliasing occurs, either with itself or
* the I cache
*
* - addr - page aligned address
*/
ENTRY(xsc3_flush_kern_dcache_page)
add r1, r0, #PAGE_SZ
1: mcr p15, 0, r0, c7, c14, 1 @ Clean/Invalidate D Cache line
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ Invalidate I cache & BTB
mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer
mcr p15, 0, r0, c7, c5, 4 @ Prefetch Flush
mov pc, lr
/*
* dma_inv_range(start, end)
*
* Invalidate (discard) the specified virtual address range.
* May not write back any entries. If 'start' or 'end'
* are not cache line aligned, those lines must be written
* back.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(xsc3_dma_inv_range)
tst r0, #CACHELINESIZE - 1
bic r0, r0, #CACHELINESIZE - 1
mcrne p15, 0, r0, c7, c10, 1 @ clean L1 D entry
mcrne p15, 1, r0, c7, c11, 1 @ clean L2 D entry
tst r1, #CACHELINESIZE - 1
mcrne p15, 0, r1, c7, c10, 1 @ clean L1 D entry
mcrne p15, 1, r1, c7, c11, 1 @ clean L2 D entry
1: mcr p15, 0, r0, c7, c6, 1 @ invalidate L1 D entry
mcr p15, 1, r0, c7, c7, 1 @ Invalidate L2 D cache line
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer
mov pc, lr
/*
* dma_clean_range(start, end)
*
* Clean the specified virtual address range.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(xsc3_dma_clean_range)
bic r0, r0, #CACHELINESIZE - 1
1: mcr p15, 0, r0, c7, c10, 1 @ clean L1 D entry
mcr p15, 1, r0, c7, c11, 1 @ clean L2 D entry
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer
mov pc, lr
/*
* dma_flush_range(start, end)
*
* Clean and invalidate the specified virtual address range.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(xsc3_dma_flush_range)
bic r0, r0, #CACHELINESIZE - 1
1: mcr p15, 0, r0, c7, c14, 1 @ Clean/invalidate L1 D cache line
mcr p15, 1, r0, c7, c11, 1 @ Clean L2 D cache line
mcr p15, 1, r0, c7, c7, 1 @ Invalidate L2 D cache line
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer
mov pc, lr
ENTRY(xsc3_cache_fns)
.long xsc3_flush_kern_cache_all
.long xsc3_flush_user_cache_all
.long xsc3_flush_user_cache_range
.long xsc3_coherent_kern_range
.long xsc3_coherent_user_range
.long xsc3_flush_kern_dcache_page
.long xsc3_dma_inv_range
.long xsc3_dma_clean_range
.long xsc3_dma_flush_range
ENTRY(cpu_xsc3_dcache_clean_area)
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
add r0, r0, #CACHELINESIZE
subs r1, r1, #CACHELINESIZE
bhi 1b
mov pc, lr
/* =============================== PageTable ============================== */
/*
* cpu_xsc3_switch_mm(pgd)
*
* Set the translation base pointer to be as described by pgd.
*
* pgd: new page tables
*/
.align 5
ENTRY(cpu_xsc3_switch_mm)
clean_d_cache r1, r2
mcr p15, 0, ip, c7, c5, 0 @ Invalidate I cache & BTB
mcr p15, 0, ip, c7, c10, 4 @ Drain Write Buffer
mcr p15, 0, ip, c7, c5, 4 @ Prefetch Flush
#ifdef L2_CACHE_ENABLE
orr r0, r0, #0x18 @ cache the page table in L2
#endif
mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
cpwait_ret lr, ip
/*
* cpu_xsc3_set_pte(ptep, pte)
*
* Set a PTE and flush it out
*
*/
.align 5
ENTRY(cpu_xsc3_set_pte)
str r1, [r0], #-2048 @ linux version
bic r2, r1, #0xdf0 @ Keep C, B, coherency bits
orr r2, r2, #PTE_TYPE_EXT @ extended page
eor r3, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
tst r3, #L_PTE_USER @ User?
orrne r2, r2, #PTE_EXT_AP_URO_SRW @ yes -> user r/o, system r/w
tst r3, #L_PTE_WRITE | L_PTE_DIRTY @ Write and Dirty?
orreq r2, r2, #PTE_EXT_AP_UNO_SRW @ yes -> user n/a, system r/w
@ combined with user -> user r/w
#if L2_CACHE_ENABLE
@ If its cacheable it needs to be in L2 also.
eor ip, r1, #L_PTE_CACHEABLE
tst ip, #L_PTE_CACHEABLE
orreq r2, r2, #PTE_EXT_TEX(0x5)
#endif
tst r3, #L_PTE_PRESENT | L_PTE_YOUNG @ Present and Young?
movne r2, #0 @ no -> fault
str r2, [r0] @ hardware version
mov ip, #0
mcr p15, 0, r0, c7, c10, 1 @ Clean D cache line mcr
mcr p15, 0, ip, c7, c10, 4 @ Drain Write Buffer
mov pc, lr
.ltorg
.align
__INIT
.type __xsc3_setup, #function
__xsc3_setup:
mov r0, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
msr cpsr_c, r0
mcr p15, 0, ip, c7, c7, 0 @ invalidate I, D caches & BTB
mcr p15, 0, ip, c7, c10, 4 @ Drain Write Buffer
mcr p15, 0, ip, c7, c5, 4 @ Prefetch Flush
mcr p15, 0, ip, c8, c7, 0 @ invalidate I, D TLBs
#if L2_CACHE_ENABLE
orr r4, r4, #0x18 @ cache the page table in L2
#endif
mcr p15, 0, r4, c2, c0, 0 @ load page table pointer
mov r0, #1 @ Allow access to CP0 and CP13
orr r0, r0, #1 << 13 @ Its undefined whether this
mcr p15, 0, r0, c15, c1, 0 @ affects USR or SVC modes
mrc p15, 0, r0, c1, c0, 1 @ get auxiliary control reg
and r0, r0, #2 @ preserve bit P bit setting
#if L2_CACHE_ENABLE
orr r0, r0, #(1 << 10) @ enable L2 for LLR cache
#endif
mcr p15, 0, r0, c1, c0, 1 @ set auxiliary control reg
mrc p15, 0, r0, c1, c0, 0 @ get control register
bic r0, r0, #0x0002 @ .... .... .... ..A.
orr r0, r0, #0x0005 @ .... .... .... .C.M
#if BTB_ENABLE
bic r0, r0, #0x0200 @ .... ..R. .... ....
orr r0, r0, #0x3900 @ ..VI Z..S .... ....
#else
bic r0, r0, #0x0a00 @ .... Z.R. .... ....
orr r0, r0, #0x3100 @ ..VI ...S .... ....
#endif
#if L2_CACHE_ENABLE
orr r0, r0, #0x4000000 @ L2 enable
#endif
mov pc, lr
.size __xsc3_setup, . - __xsc3_setup
__INITDATA
/*
* Purpose : Function pointers used to access above functions - all calls
* come through these
*/
.type xsc3_processor_functions, #object
ENTRY(xsc3_processor_functions)
.word v5t_early_abort
.word cpu_xsc3_proc_init
.word cpu_xsc3_proc_fin
.word cpu_xsc3_reset
.word cpu_xsc3_do_idle
.word cpu_xsc3_dcache_clean_area
.word cpu_xsc3_switch_mm
.word cpu_xsc3_set_pte
.size xsc3_processor_functions, . - xsc3_processor_functions
.section ".rodata"
.type cpu_arch_name, #object
cpu_arch_name:
.asciz "armv5te"
.size cpu_arch_name, . - cpu_arch_name
.type cpu_elf_name, #object
cpu_elf_name:
.asciz "v5"
.size cpu_elf_name, . - cpu_elf_name
.type cpu_xsc3_name, #object
cpu_xsc3_name:
.asciz "XScale-Core3"
.size cpu_xsc3_name, . - cpu_xsc3_name
.align
.section ".proc.info.init", #alloc, #execinstr
.type __xsc3_proc_info,#object
__xsc3_proc_info:
.long 0x69056000
.long 0xffffe000
.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 __xsc3_setup
.long cpu_arch_name
.long cpu_elf_name
.long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
.long cpu_xsc3_name
.long xsc3_processor_functions
.long v4wbi_tlb_fns
.long xsc3_mc_user_fns
.long xsc3_cache_fns
.size __xsc3_proc_info, . - __xsc3_proc_info