kernel-ark/arch/arm/mm/cache-v4wb.S
Mika Westerberg c8c90860cd ARM: 6466/1: implement flush_icache_all for the rest of the CPUs
Commit 81d11955bf ("ARM: 6405/1: Handle __flush_icache_all for
CONFIG_SMP_ON_UP") added a new function to struct cpu_cache_fns:
flush_icache_all(). It also implemented this for v6 and v7 but not
for v5 and backwards. Without the function pointer in place, we
will be calling wrong cache functions.

For example with ep93xx we get following:

    Unable to handle kernel paging request at virtual address ee070f38
    pgd = c0004000
    [ee070f38] *pgd=00000000
    Internal error: Oops: 80000005 [#1] PREEMPT
    last sysfs file:
    Modules linked in:
    CPU: 0    Not tainted  (2.6.36+ #1)
    PC is at 0xee070f38
    LR is at __dma_alloc+0x11c/0x2d0
    pc : [<ee070f38>]    lr : [<c0032c8c>]    psr: 60000013
    sp : c581bde0  ip : 00000000  fp : c0472000
    r10: c0472000  r9 : 000000d0  r8 : 00020000
    r7 : 0001ffff  r6 : 00000000  r5 : c0472400  r4 : c5980000
    r3 : c03ab7e0  r2 : 00000000  r1 : c59a0000  r0 : c5980000
    Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
    Control: c000717f  Table: c0004000  DAC: 00000017
    Process swapper (pid: 1, stack limit = 0xc581a270)
    [<c0032c8c>] (__dma_alloc+0x11c/0x2d0)
    [<c0032e5c>] (dma_alloc_writecombine+0x1c/0x24)
    [<c0204148>] (ep93xx_pcm_preallocate_dma_buffer+0x44/0x60)
    [<c02041c0>] (ep93xx_pcm_new+0x5c/0x88)
    [<c01ff188>] (snd_soc_instantiate_cards+0x8a8/0xbc0)
    [<c01ff59c>] (soc_probe+0xfc/0x134)
    [<c01adafc>] (platform_drv_probe+0x18/0x1c)
    [<c01acca4>] (driver_probe_device+0xb0/0x16c)
    [<c01ac284>] (bus_for_each_drv+0x48/0x84)
    [<c01ace90>] (device_attach+0x50/0x68)
    [<c01ac0f8>] (bus_probe_device+0x24/0x44)
    [<c01aad7c>] (device_add+0x2fc/0x44c)
    [<c01adfa8>] (platform_device_add+0x104/0x15c)
    [<c0015eb8>] (simone_init+0x60/0x94)
    [<c0021410>] (do_one_initcall+0xd0/0x1a4)

__dma_alloc() calls (inlined) __dma_alloc_buffer() which ends up
calling dmac_flush_range(). Now since the entries in the
arm920_cache_fns are shifted by one, we jump into address 0xee070f38
which is actually next instruction after the arm920_cache_fns
structure.

So implement flush_icache_all() for the rest of the supported CPUs
using a generic 'invalidate I cache' instruction.

Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-28 13:54:28 +01:00

269 lines
6.4 KiB
ArmAsm

/*
* linux/arch/arm/mm/cache-v4wb.S
*
* Copyright (C) 1997-2002 Russell king
*
* 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.
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/memory.h>
#include <asm/page.h>
#include "proc-macros.S"
/*
* The size of one data cache line.
*/
#define CACHE_DLINESIZE 32
/*
* The total size of the data cache.
*/
#if defined(CONFIG_CPU_SA110)
# define CACHE_DSIZE 16384
#elif defined(CONFIG_CPU_SA1100)
# define CACHE_DSIZE 8192
#else
# error Unknown cache size
#endif
/*
* This is the size at which it becomes more efficient to
* clean the whole cache, rather than using the individual
* cache line maintainence instructions.
*
* Size Clean (ticks) Dirty (ticks)
* 4096 21 20 21 53 55 54
* 8192 40 41 40 106 100 102
* 16384 77 77 76 140 140 138
* 32768 150 149 150 214 216 212 <---
* 65536 296 297 296 351 358 361
* 131072 591 591 591 656 657 651
* Whole 132 136 132 221 217 207 <---
*/
#define CACHE_DLIMIT (CACHE_DSIZE * 4)
.data
flush_base:
.long FLUSH_BASE
.text
/*
* flush_icache_all()
*
* Unconditionally clean and invalidate the entire icache.
*/
ENTRY(v4wb_flush_icache_all)
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
mov pc, lr
ENDPROC(v4wb_flush_icache_all)
/*
* flush_user_cache_all()
*
* Clean and invalidate all cache entries in a particular address
* space.
*/
ENTRY(v4wb_flush_user_cache_all)
/* FALLTHROUGH */
/*
* flush_kern_cache_all()
*
* Clean and invalidate the entire cache.
*/
ENTRY(v4wb_flush_kern_cache_all)
mov ip, #0
mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
__flush_whole_cache:
ldr r3, =flush_base
ldr r1, [r3, #0]
eor r1, r1, #CACHE_DSIZE
str r1, [r3, #0]
add r2, r1, #CACHE_DSIZE
1: ldr r3, [r1], #32
cmp r1, r2
blo 1b
#ifdef FLUSH_BASE_MINICACHE
add r2, r2, #FLUSH_BASE_MINICACHE - FLUSH_BASE
sub r1, r2, #512 @ only 512 bytes
1: ldr r3, [r1], #32
cmp r1, r2
blo 1b
#endif
mcr p15, 0, ip, c7, c10, 4 @ drain write buffer
mov pc, lr
/*
* flush_user_cache_range(start, end, flags)
*
* Invalidate a range of cache entries in the specified
* address space.
*
* - start - start address (inclusive, page aligned)
* - end - end address (exclusive, page aligned)
* - flags - vma_area_struct flags describing address space
*/
ENTRY(v4wb_flush_user_cache_range)
mov ip, #0
sub r3, r1, r0 @ calculate total size
tst r2, #VM_EXEC @ executable region?
mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
cmp r3, #CACHE_DLIMIT @ total size >= limit?
bhs __flush_whole_cache @ flush whole D cache
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
add r0, r0, #CACHE_DLINESIZE
cmp r0, r1
blo 1b
tst r2, #VM_EXEC
mcrne p15, 0, ip, c7, c10, 4 @ drain write buffer
mov pc, lr
/*
* flush_kern_dcache_area(void *addr, size_t size)
*
* Ensure no D cache aliasing occurs, either with itself or
* the I cache
*
* - addr - kernel address
* - size - region size
*/
ENTRY(v4wb_flush_kern_dcache_area)
add r1, r0, r1
/* fall through */
/*
* 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
*/
ENTRY(v4wb_coherent_kern_range)
/* fall through */
/*
* coherent_user_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
*/
ENTRY(v4wb_coherent_user_range)
bic r0, r0, #CACHE_DLINESIZE - 1
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
add r0, r0, #CACHE_DLINESIZE
cmp r0, r1
blo 1b
mov ip, #0
mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
mcr p15, 0, ip, c7, c10, 4 @ drain WB
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
*/
v4wb_dma_inv_range:
tst r0, #CACHE_DLINESIZE - 1
bic r0, r0, #CACHE_DLINESIZE - 1
mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
tst r1, #CACHE_DLINESIZE - 1
mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
add r0, r0, #CACHE_DLINESIZE
cmp r0, r1
blo 1b
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
mov pc, lr
/*
* dma_clean_range(start, end)
*
* Clean (write back) the specified virtual address range.
*
* - start - virtual start address
* - end - virtual end address
*/
v4wb_dma_clean_range:
bic r0, r0, #CACHE_DLINESIZE - 1
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
add r0, r0, #CACHE_DLINESIZE
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
*
* This is actually the same as v4wb_coherent_kern_range()
*/
.globl v4wb_dma_flush_range
.set v4wb_dma_flush_range, v4wb_coherent_kern_range
/*
* dma_map_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(v4wb_dma_map_area)
add r1, r1, r0
cmp r2, #DMA_TO_DEVICE
beq v4wb_dma_clean_range
bcs v4wb_dma_inv_range
b v4wb_dma_flush_range
ENDPROC(v4wb_dma_map_area)
/*
* dma_unmap_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(v4wb_dma_unmap_area)
mov pc, lr
ENDPROC(v4wb_dma_unmap_area)
__INITDATA
.type v4wb_cache_fns, #object
ENTRY(v4wb_cache_fns)
.long v4wb_flush_icache_all
.long v4wb_flush_kern_cache_all
.long v4wb_flush_user_cache_all
.long v4wb_flush_user_cache_range
.long v4wb_coherent_kern_range
.long v4wb_coherent_user_range
.long v4wb_flush_kern_dcache_area
.long v4wb_dma_map_area
.long v4wb_dma_unmap_area
.long v4wb_dma_flush_range
.size v4wb_cache_fns, . - v4wb_cache_fns