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linux/arch/arm/mm/proc-arm940.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

405 lines
10 KiB
ArmAsm

/*
* linux/arch/arm/mm/arm940.S: utility functions for ARM940T
*
* Copyright (C) 2004-2006 Hyok S. Choi (hyok.choi@samsung.com)
*
* 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/assembler.h>
#include <asm/hwcap.h>
#include <asm/pgtable-hwdef.h>
#include <asm/pgtable.h>
#include <asm/ptrace.h>
#include "proc-macros.S"
/* ARM940T has a 4KB DCache comprising 256 lines of 4 words */
#define CACHE_DLINESIZE 16
#define CACHE_DSEGMENTS 4
#define CACHE_DENTRIES 64
.text
/*
* cpu_arm940_proc_init()
* cpu_arm940_switch_mm()
*
* These are not required.
*/
ENTRY(cpu_arm940_proc_init)
ENTRY(cpu_arm940_switch_mm)
mov pc, lr
/*
* cpu_arm940_proc_fin()
*/
ENTRY(cpu_arm940_proc_fin)
mrc p15, 0, r0, c1, c0, 0 @ ctrl register
bic r0, r0, #0x00001000 @ i-cache
bic r0, r0, #0x00000004 @ d-cache
mcr p15, 0, r0, c1, c0, 0 @ disable caches
mov pc, lr
/*
* cpu_arm940_reset(loc)
* Params : r0 = address to jump to
* Notes : This sets up everything for a reset
*/
ENTRY(cpu_arm940_reset)
mov ip, #0
mcr p15, 0, ip, c7, c5, 0 @ flush I cache
mcr p15, 0, ip, c7, c6, 0 @ flush D cache
mcr p15, 0, ip, c7, c10, 4 @ drain WB
mrc p15, 0, ip, c1, c0, 0 @ ctrl register
bic ip, ip, #0x00000005 @ .............c.p
bic ip, ip, #0x00001000 @ i-cache
mcr p15, 0, ip, c1, c0, 0 @ ctrl register
mov pc, r0
/*
* cpu_arm940_do_idle()
*/
.align 5
ENTRY(cpu_arm940_do_idle)
mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
mov pc, lr
/*
* flush_icache_all()
*
* Unconditionally clean and invalidate the entire icache.
*/
ENTRY(arm940_flush_icache_all)
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
mov pc, lr
ENDPROC(arm940_flush_icache_all)
/*
* flush_user_cache_all()
*/
ENTRY(arm940_flush_user_cache_all)
/* FALLTHROUGH */
/*
* flush_kern_cache_all()
*
* Clean and invalidate the entire cache.
*/
ENTRY(arm940_flush_kern_cache_all)
mov r2, #VM_EXEC
/* FALLTHROUGH */
/*
* flush_user_cache_range(start, end, flags)
*
* There is no efficient way to flush a range of cache entries
* in the specified address range. Thus, flushes all.
*
* - start - start address (inclusive)
* - end - end address (exclusive)
* - flags - vm_flags describing address space
*/
ENTRY(arm940_flush_user_cache_range)
mov ip, #0
#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
mcr p15, 0, ip, c7, c6, 0 @ flush D cache
#else
mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments
1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
2: mcr p15, 0, r3, c7, c14, 2 @ clean/flush D index
subs r3, r3, #1 << 26
bcs 2b @ entries 63 to 0
subs r1, r1, #1 << 4
bcs 1b @ segments 3 to 0
#endif
tst r2, #VM_EXEC
mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
mcrne p15, 0, ip, c7, c10, 4 @ drain WB
mov pc, lr
/*
* coherent_kern_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start, end. If you have non-snooping
* Harvard caches, you need to implement this function.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(arm940_coherent_kern_range)
/* FALLTHROUGH */
/*
* coherent_user_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start, end. If you have non-snooping
* Harvard caches, you need to implement this function.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(arm940_coherent_user_range)
/* FALLTHROUGH */
/*
* 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(arm940_flush_kern_dcache_area)
mov ip, #0
mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments
1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
2: mcr p15, 0, r3, c7, c14, 2 @ clean/flush D index
subs r3, r3, #1 << 26
bcs 2b @ entries 63 to 0
subs r1, r1, #1 << 4
bcs 1b @ segments 7 to 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)
*
* There is no efficient way to invalidate a specifid virtual
* address range. Thus, invalidates all.
*
* - start - virtual start address
* - end - virtual end address
*/
arm940_dma_inv_range:
mov ip, #0
mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments
1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
2: mcr p15, 0, r3, c7, c6, 2 @ flush D entry
subs r3, r3, #1 << 26
bcs 2b @ entries 63 to 0
subs r1, r1, #1 << 4
bcs 1b @ segments 7 to 0
mcr p15, 0, ip, c7, c10, 4 @ drain WB
mov pc, lr
/*
* dma_clean_range(start, end)
*
* There is no efficient way to clean a specifid virtual
* address range. Thus, cleans all.
*
* - start - virtual start address
* - end - virtual end address
*/
arm940_dma_clean_range:
ENTRY(cpu_arm940_dcache_clean_area)
mov ip, #0
#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments
1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
2: mcr p15, 0, r3, c7, c10, 2 @ clean D entry
subs r3, r3, #1 << 26
bcs 2b @ entries 63 to 0
subs r1, r1, #1 << 4
bcs 1b @ segments 7 to 0
#endif
mcr p15, 0, ip, c7, c10, 4 @ drain WB
mov pc, lr
/*
* dma_flush_range(start, end)
*
* There is no efficient way to clean and invalidate a specifid
* virtual address range.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(arm940_dma_flush_range)
mov ip, #0
mov r1, #(CACHE_DSEGMENTS - 1) << 4 @ 4 segments
1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
2:
#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
mcr p15, 0, r3, c7, c14, 2 @ clean/flush D entry
#else
mcr p15, 0, r3, c7, c6, 2 @ invalidate D entry
#endif
subs r3, r3, #1 << 26
bcs 2b @ entries 63 to 0
subs r1, r1, #1 << 4
bcs 1b @ segments 7 to 0
mcr p15, 0, ip, c7, c10, 4 @ drain WB
mov pc, lr
/*
* dma_map_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(arm940_dma_map_area)
add r1, r1, r0
cmp r2, #DMA_TO_DEVICE
beq arm940_dma_clean_range
bcs arm940_dma_inv_range
b arm940_dma_flush_range
ENDPROC(arm940_dma_map_area)
/*
* dma_unmap_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(arm940_dma_unmap_area)
mov pc, lr
ENDPROC(arm940_dma_unmap_area)
ENTRY(arm940_cache_fns)
.long arm940_flush_icache_all
.long arm940_flush_kern_cache_all
.long arm940_flush_user_cache_all
.long arm940_flush_user_cache_range
.long arm940_coherent_kern_range
.long arm940_coherent_user_range
.long arm940_flush_kern_dcache_area
.long arm940_dma_map_area
.long arm940_dma_unmap_area
.long arm940_dma_flush_range
__CPUINIT
.type __arm940_setup, #function
__arm940_setup:
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
mcr p15, 0, r0, c7, c6, 0 @ invalidate D cache
mcr p15, 0, r0, c7, c10, 4 @ drain WB
mcr p15, 0, r0, c6, c3, 0 @ disable data area 3~7
mcr p15, 0, r0, c6, c4, 0
mcr p15, 0, r0, c6, c5, 0
mcr p15, 0, r0, c6, c6, 0
mcr p15, 0, r0, c6, c7, 0
mcr p15, 0, r0, c6, c3, 1 @ disable instruction area 3~7
mcr p15, 0, r0, c6, c4, 1
mcr p15, 0, r0, c6, c5, 1
mcr p15, 0, r0, c6, c6, 1
mcr p15, 0, r0, c6, c7, 1
mov r0, #0x0000003F @ base = 0, size = 4GB
mcr p15, 0, r0, c6, c0, 0 @ set area 0, default
mcr p15, 0, r0, c6, c0, 1
ldr r0, =(CONFIG_DRAM_BASE & 0xFFFFF000) @ base[31:12] of RAM
ldr r1, =(CONFIG_DRAM_SIZE >> 12) @ size of RAM (must be >= 4KB)
mov r2, #10 @ 11 is the minimum (4KB)
1: add r2, r2, #1 @ area size *= 2
mov r1, r1, lsr #1
bne 1b @ count not zero r-shift
orr r0, r0, r2, lsl #1 @ the area register value
orr r0, r0, #1 @ set enable bit
mcr p15, 0, r0, c6, c1, 0 @ set area 1, RAM
mcr p15, 0, r0, c6, c1, 1
ldr r0, =(CONFIG_FLASH_MEM_BASE & 0xFFFFF000) @ base[31:12] of FLASH
ldr r1, =(CONFIG_FLASH_SIZE >> 12) @ size of FLASH (must be >= 4KB)
mov r2, #10 @ 11 is the minimum (4KB)
1: add r2, r2, #1 @ area size *= 2
mov r1, r1, lsr #1
bne 1b @ count not zero r-shift
orr r0, r0, r2, lsl #1 @ the area register value
orr r0, r0, #1 @ set enable bit
mcr p15, 0, r0, c6, c2, 0 @ set area 2, ROM/FLASH
mcr p15, 0, r0, c6, c2, 1
mov r0, #0x06
mcr p15, 0, r0, c2, c0, 0 @ Region 1&2 cacheable
mcr p15, 0, r0, c2, c0, 1
#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
mov r0, #0x00 @ disable whole write buffer
#else
mov r0, #0x02 @ Region 1 write bufferred
#endif
mcr p15, 0, r0, c3, c0, 0
mov r0, #0x10000
sub r0, r0, #1 @ r0 = 0xffff
mcr p15, 0, r0, c5, c0, 0 @ all read/write access
mcr p15, 0, r0, c5, c0, 1
mrc p15, 0, r0, c1, c0 @ get control register
orr r0, r0, #0x00001000 @ I-cache
orr r0, r0, #0x00000005 @ MPU/D-cache
mov pc, lr
.size __arm940_setup, . - __arm940_setup
__INITDATA
/*
* Purpose : Function pointers used to access above functions - all calls
* come through these
*/
.type arm940_processor_functions, #object
ENTRY(arm940_processor_functions)
.word nommu_early_abort
.word legacy_pabort
.word cpu_arm940_proc_init
.word cpu_arm940_proc_fin
.word cpu_arm940_reset
.word cpu_arm940_do_idle
.word cpu_arm940_dcache_clean_area
.word cpu_arm940_switch_mm
.word 0 @ cpu_*_set_pte
.size arm940_processor_functions, . - arm940_processor_functions
.section ".rodata"
.type cpu_arch_name, #object
cpu_arch_name:
.asciz "armv4t"
.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_arm940_name, #object
cpu_arm940_name:
.ascii "ARM940T"
.size cpu_arm940_name, . - cpu_arm940_name
.align
.section ".proc.info.init", #alloc, #execinstr
.type __arm940_proc_info,#object
__arm940_proc_info:
.long 0x41009400
.long 0xff00fff0
.long 0
b __arm940_setup
.long cpu_arch_name
.long cpu_elf_name
.long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
.long cpu_arm940_name
.long arm940_processor_functions
.long 0
.long 0
.long arm940_cache_fns
.size __arm940_proc_info, . - __arm940_proc_info