/*
* linux/arch/arm/mm/proc-xscale.S
*
* Author: Nicolas Pitre
* Created: November 2000
* Copyright: (C) 2000, 2001 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 XScale CPUs
*
* 2001 Aug 21:
* some contributions by Brett Gaines <brett.w.gaines@intel.com>
* Copyright 2001 by Intel Corp.
*
* 2001 Sep 08:
* Completely revisited, many important fixes
* Nicolas Pitre <nico@fluxnic.net>
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/assembler.h>
#include <asm/hwcap.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
/*
* Virtual address used to allocate the cache when flushed
*
* This must be an address range which is _never_ used. It should
* apparently have a mapping in the corresponding page table for
* compatibility with future CPUs that _could_ require it. For instance we
* don't care.
*
* This must be aligned on a 2*CACHESIZE boundary. The code selects one of
* the 2 areas in alternance each time the clean_d_cache macro is used.
* Without this the XScale core exhibits cache eviction problems and no one
* knows why.
*
* Reminder: the vector table is located at 0xffff0000-0xffff0fff.
*/
#define CLEAN_ADDR 0xfffe0000
/*
* 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, rd
mrc p15, 0, \rd, c2, c0, 0 @ arbitrary read of cp15
mov \rd, \rd @ wait for completion
sub pc, pc, #4 @ flush instruction pipeline
.endm
.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 the entire dcache using line allocate.
* The main loop has been unrolled to reduce loop overhead.
* rd and rs are two scratch registers.
*/
.macro clean_d_cache, rd, rs
ldr \rs, =clean_addr
ldr \rd, [\rs]
eor \rd, \rd, #CACHESIZE
str \rd, [\rs]
add \rs, \rd, #CACHESIZE
1: mcr p15, 0, \rd, c7, c2, 5 @ allocate D cache line
add \rd, \rd, #CACHELINESIZE
mcr p15, 0, \rd, c7, c2, 5 @ allocate D cache line
add \rd, \rd, #CACHELINESIZE
mcr p15, 0, \rd, c7, c2, 5 @ allocate D cache line
add \rd, \rd, #CACHELINESIZE
mcr p15, 0, \rd, c7, c2, 5 @ allocate D cache line
add \rd, \rd, #CACHELINESIZE
teq \rd, \rs
bne 1b
.endm
.data
clean_addr: .word CLEAN_ADDR
.text
/*
* cpu_xscale_proc_init()
*
* Nothing too exciting at the moment
*/
ENTRY(cpu_xscale_proc_init)
@ enable write buffer coalescing. Some bootloader disable it
mrc p15, 0, r1, c1, c0, 1
bic r1, r1, #1
mcr p15, 0, r1, c1, c0, 1
ret lr
/*
* cpu_xscale_proc_fin()
*/
ENTRY(cpu_xscale_proc_fin)
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
ret lr
/*
* cpu_xscale_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
*
* Beware PXA270 erratum E7.
*/
.align 5
.pushsection .idmap.text, "ax"
ENTRY(cpu_xscale_reset)
mov r1, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
msr cpsr_c, r1 @ reset CPSR
mcr p15, 0, r1, c10, c4, 1 @ unlock I-TLB
mcr p15, 0, r1, c8, c5, 0 @ invalidate I-TLB
mrc p15, 0, r1, c1, c0, 0 @ ctrl register
bic r1, r1, #0x0086 @ ........B....CA.
bic r1, r1, #0x3900 @ ..VIZ..S........
sub pc, pc, #4 @ flush pipeline
@ *** cache line aligned ***
mcr p15, 0, r1, c1, c0, 0 @ ctrl register
bic r1, r1, #0x0001 @ ...............M
mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches & BTB
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
ret r0
ENDPROC(cpu_xscale_reset)
.popsection
/*
* cpu_xscale_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.
*/
.align 5
ENTRY(cpu_xscale_do_idle)
mov r0, #1
mcr p14, 0, r0, c7, c0, 0 @ Go to IDLE
ret lr
/* ================================= CACHE ================================ */
/*
* flush_icache_all()
*
* Unconditionally clean and invalidate the entire icache.
*/
ENTRY(xscale_flush_icache_all)
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
ret lr
ENDPROC(xscale_flush_icache_all)
/*
* flush_user_cache_all()
*
* Invalidate all cache entries in a particular address
* space.
*/
ENTRY(xscale_flush_user_cache_all)
/* FALLTHROUGH */
/*
* flush_kern_cache_all()
*
* Clean and invalidate the entire cache.
*/
ENTRY(xscale_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 (& Fill) Buffer
ret 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(xscale_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, c10, 1 @ Clean D cache line
mcr p15, 0, r0, c7, c6, 1 @ 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 (& Fill) Buffer
ret 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(xscale_coherent_kern_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 (& Fill) Buffer
ret lr
/*
* 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(xscale_coherent_user_range)
bic r0, r0, #CACHELINESIZE - 1
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
mcr p15, 0, r0, c7, c5, 1 @ Invalidate I cache entry
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mov r0, #0
mcr p15, 0, r0, c7, c5, 6 @ Invalidate BTB
mcr p15, 0, r0, c7, c10, 4 @ Drain Write (& Fill) Buffer
ret 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(xscale_flush_kern_dcache_area)
add r1, r0, r1
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
mcr p15, 0, r0, c7, c6, 1 @ invalidate 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 (& Fill) Buffer
ret 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
*/
xscale_dma_inv_range:
tst r0, #CACHELINESIZE - 1
bic r0, r0, #CACHELINESIZE - 1
mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
tst r1, #CACHELINESIZE - 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, #CACHELINESIZE
cmp r0, r1
blo 1b
mcr p15, 0, r0, c7, c10, 4 @ Drain Write (& Fill) Buffer
ret lr
/*
* dma_clean_range(start, end)
*
* Clean the specified virtual address range.
*
* - start - virtual start address
* - end - virtual end address
*/
xscale_dma_clean_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
mcr p15, 0, r0, c7, c10, 4 @ Drain Write (& Fill) Buffer
ret lr
/*
* dma_flush_range(start, end)
*
* Clean and invalidate the specified virtual address range.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(xscale_dma_flush_range)
bic r0, r0, #CACHELINESIZE - 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, #CACHELINESIZE
cmp r0, r1
blo 1b
mcr p15, 0, r0, c7, c10, 4 @ Drain Write (& Fill) Buffer
ret lr
/*
* dma_map_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(xscale_dma_map_area)
add r1, r1, r0
cmp r2, #DMA_TO_DEVICE
beq xscale_dma_clean_range
bcs xscale_dma_inv_range
b xscale_dma_flush_range
ENDPROC(xscale_dma_map_area)
/*
* dma_map_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(xscale_80200_A0_A1_dma_map_area)
add r1, r1, r0
teq r2, #DMA_TO_DEVICE
beq xscale_dma_clean_range
b xscale_dma_flush_range
ENDPROC(xscale_80200_A0_A1_dma_map_area)
/*
* dma_unmap_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(xscale_dma_unmap_area)
ret lr
ENDPROC(xscale_dma_unmap_area)
.globl xscale_flush_kern_cache_louis
.equ xscale_flush_kern_cache_louis, xscale_flush_kern_cache_all
@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
define_cache_functions xscale
/*
* On stepping A0/A1 of the 80200, invalidating D-cache by line doesn't
* clear the dirty bits, which means that if we invalidate a dirty line,
* the dirty data can still be written back to external memory later on.
*
* The recommended workaround is to always do a clean D-cache line before
* doing an invalidate D-cache line, so on the affected processors,
* dma_inv_range() is implemented as dma_flush_range().
*
* See erratum #25 of "Intel 80200 Processor Specification Update",
* revision January 22, 2003, available at:
* http://www.intel.com/design/iio/specupdt/273415.htm
*/
.macro a0_alias basename
.globl xscale_80200_A0_A1_\basename
.type xscale_80200_A0_A1_\basename , %function
.equ xscale_80200_A0_A1_\basename , xscale_\basename
.endm
/*
* Most of the cache functions are unchanged for these processor revisions.
* Export suitable alias symbols for the unchanged functions:
*/
a0_alias flush_icache_all
a0_alias flush_user_cache_all
a0_alias flush_kern_cache_all
a0_alias flush_kern_cache_louis
a0_alias flush_user_cache_range
a0_alias coherent_kern_range
a0_alias coherent_user_range
a0_alias flush_kern_dcache_area
a0_alias dma_flush_range
a0_alias dma_unmap_area
@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
define_cache_functions xscale_80200_A0_A1
ENTRY(cpu_xscale_dcache_clean_area)
1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
add r0, r0, #CACHELINESIZE
subs r1, r1, #CACHELINESIZE
bhi 1b
ret lr
/* =============================== PageTable ============================== */
/*
* cpu_xscale_switch_mm(pgd)
*
* Set the translation base pointer to be as described by pgd.
*
* pgd: new page tables
*/
.align 5
ENTRY(cpu_xscale_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 (& Fill) Buffer
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_xscale_set_pte_ext(ptep, pte, ext)
*
* Set a PTE and flush it out
*
* Errata 40: must set memory to write-through for user read-only pages.
*/
cpu_xscale_mt_table:
.long 0x00 @ L_PTE_MT_UNCACHED
.long PTE_BUFFERABLE @ L_PTE_MT_BUFFERABLE
.long PTE_CACHEABLE @ L_PTE_MT_WRITETHROUGH
.long PTE_CACHEABLE | PTE_BUFFERABLE @ L_PTE_MT_WRITEBACK
.long PTE_EXT_TEX(1) | PTE_BUFFERABLE @ L_PTE_MT_DEV_SHARED
.long 0x00 @ unused
.long PTE_EXT_TEX(1) | PTE_CACHEABLE @ L_PTE_MT_MINICACHE
.long PTE_EXT_TEX(1) | PTE_CACHEABLE | PTE_BUFFERABLE @ L_PTE_MT_WRITEALLOC
.long 0x00 @ unused
.long PTE_BUFFERABLE @ L_PTE_MT_DEV_WC
.long 0x00 @ unused
.long PTE_CACHEABLE | PTE_BUFFERABLE @ L_PTE_MT_DEV_CACHED
.long 0x00 @ L_PTE_MT_DEV_NONSHARED
.long 0x00 @ unused
.long 0x00 @ unused
.long 0x00 @ unused
.align 5
ENTRY(cpu_xscale_set_pte_ext)
xscale_set_pte_ext_prologue
@
@ Erratum 40: must set memory to write-through for user read-only pages
@
and ip, r1, #(L_PTE_MT_MASK | L_PTE_USER | L_PTE_RDONLY) & ~(4 << 2)
teq ip, #L_PTE_MT_WRITEBACK | L_PTE_USER | L_PTE_RDONLY
moveq r1, #L_PTE_MT_WRITETHROUGH
and r1, r1, #L_PTE_MT_MASK
adr ip, cpu_xscale_mt_table
ldr ip, [ip, r1]
bic r2, r2, #0x0c
orr r2, r2, ip
xscale_set_pte_ext_epilogue
ret lr
.ltorg
.align
.globl cpu_xscale_suspend_size
.equ cpu_xscale_suspend_size, 4 * 6
#ifdef CONFIG_ARM_CPU_SUSPEND
ENTRY(cpu_xscale_do_suspend)
stmfd sp!, {r4 - r9, lr}
mrc p14, 0, r4, c6, c0, 0 @ clock configuration, for turbo mode
mrc p15, 0, r5, c15, c1, 0 @ CP access reg
mrc p15, 0, r6, c13, c0, 0 @ PID
mrc p15, 0, r7, c3, c0, 0 @ domain ID
mrc p15, 0, r8, c1, c0, 1 @ auxiliary control reg
mrc p15, 0, r9, c1, c0, 0 @ control reg
bic r4, r4, #2 @ clear frequency change bit
stmia r0, {r4 - r9} @ store cp regs
ldmfd sp!, {r4 - r9, pc}
ENDPROC(cpu_xscale_do_suspend)
ENTRY(cpu_xscale_do_resume)
ldmia r0, {r4 - r9} @ load cp regs
mov ip, #0
mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
mcr p15, 0, ip, c7, c7, 0 @ invalidate I & D caches, BTB
mcr p14, 0, r4, c6, c0, 0 @ clock configuration, turbo mode.
mcr p15, 0, r5, c15, c1, 0 @ CP access reg
mcr p15, 0, r6, c13, c0, 0 @ PID
mcr p15, 0, r7, c3, c0, 0 @ domain ID
mcr p15, 0, r1, c2, c0, 0 @ translation table base addr
mcr p15, 0, r8, c1, c0, 1 @ auxiliary control reg
mov r0, r9 @ control register
b cpu_resume_mmu
ENDPROC(cpu_xscale_do_resume)
#endif
.type __xscale_setup, #function
__xscale_setup:
mcr p15, 0, ip, c7, c7, 0 @ invalidate I, D caches & BTB
mcr p15, 0, ip, c7, c10, 4 @ Drain Write (& Fill) Buffer
mcr p15, 0, ip, c8, c7, 0 @ invalidate I, D TLBs
mov r0, #1 << 6 @ cp6 for IOP3xx and Bulverde
orr r0, r0, #1 << 13 @ Its undefined whether this
mcr p15, 0, r0, c15, c1, 0 @ affects USR or SVC modes
adr r5, xscale_crval
ldmia r5, {r5, r6}
mrc p15, 0, r0, c1, c0, 0 @ get control register
bic r0, r0, r5
orr r0, r0, r6
ret lr
.size __xscale_setup, . - __xscale_setup
/*
* R
* .RVI ZFRS BLDP WCAM
* ..11 1.01 .... .101
*
*/
.type xscale_crval, #object
xscale_crval:
crval clear=0x00003b07, mmuset=0x00003905, ucset=0x00001900
__INITDATA
@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
define_processor_functions xscale, dabort=v5t_early_abort, pabort=legacy_pabort, suspend=1
.section ".rodata"
string cpu_arch_name, "armv5te"
string cpu_elf_name, "v5"
string cpu_80200_A0_A1_name, "XScale-80200 A0/A1"
string cpu_80200_name, "XScale-80200"
string cpu_80219_name, "XScale-80219"
string cpu_8032x_name, "XScale-IOP8032x Family"
string cpu_8033x_name, "XScale-IOP8033x Family"
string cpu_pxa250_name, "XScale-PXA250"
string cpu_pxa210_name, "XScale-PXA210"
string cpu_ixp42x_name, "XScale-IXP42x Family"
string cpu_ixp43x_name, "XScale-IXP43x Family"
string cpu_ixp46x_name, "XScale-IXP46x Family"
string cpu_ixp2400_name, "XScale-IXP2400"
string cpu_ixp2800_name, "XScale-IXP2800"
string cpu_pxa255_name, "XScale-PXA255"
string cpu_pxa270_name, "XScale-PXA270"
.align
.section ".proc.info.init", #alloc
.macro xscale_proc_info name:req, cpu_val:req, cpu_mask:req, cpu_name:req, cache
.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
initfn __xscale_setup, __\name\()_proc_info
.long cpu_arch_name
.long cpu_elf_name
.long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
.long \cpu_name
.long xscale_processor_functions
.long v4wbi_tlb_fns
.long xscale_mc_user_fns
.ifb \cache
.long xscale_cache_fns
.else
.long \cache
.endif
.size __\name\()_proc_info, . - __\name\()_proc_info
.endm
xscale_proc_info 80200_A0_A1, 0x69052000, 0xfffffffe, cpu_80200_name, \
cache=xscale_80200_A0_A1_cache_fns
xscale_proc_info 80200, 0x69052000, 0xfffffff0, cpu_80200_name
xscale_proc_info 80219, 0x69052e20, 0xffffffe0, cpu_80219_name
xscale_proc_info 8032x, 0x69052420, 0xfffff7e0, cpu_8032x_name
xscale_proc_info 8033x, 0x69054010, 0xfffffd30, cpu_8033x_name
xscale_proc_info pxa250, 0x69052100, 0xfffff7f0, cpu_pxa250_name
xscale_proc_info pxa210, 0x69052120, 0xfffff3f0, cpu_pxa210_name
xscale_proc_info ixp2400, 0x69054190, 0xfffffff0, cpu_ixp2400_name
xscale_proc_info ixp2800, 0x690541a0, 0xfffffff0, cpu_ixp2800_name
xscale_proc_info ixp42x, 0x690541c0, 0xffffffc0, cpu_ixp42x_name
xscale_proc_info ixp43x, 0x69054040, 0xfffffff0, cpu_ixp43x_name
xscale_proc_info ixp46x, 0x69054200, 0xffffff00, cpu_ixp46x_name
xscale_proc_info pxa255, 0x69052d00, 0xfffffff0, cpu_pxa255_name
xscale_proc_info pxa270, 0x69054110, 0xfffffff0, cpu_pxa270_name
