kernel-ark/arch/arm/mm/proc-xsc3.S
Lorenzo Pieralisi 031bd879f7 ARM: mm: implement LoUIS API for cache maintenance ops
ARM v7 architecture introduced the concept of cache levels and related
control registers. New processors like A7 and A15 embed an L2 unified cache
controller that becomes part of the cache level hierarchy. Some operations in
the kernel like cpu_suspend and __cpu_disable do not require a flush of the
entire cache hierarchy to DRAM but just the cache levels belonging to the
Level of Unification Inner Shareable (LoUIS), which in most of ARM v7 systems
correspond to L1.

The current cache flushing API used in cpu_suspend and __cpu_disable,
flush_cache_all(), ends up flushing the whole cache hierarchy since for
v7 it cleans and invalidates all cache levels up to Level of Coherency
(LoC) which cripples system performance when used in hot paths like hotplug
and cpuidle.

Therefore a new kernel cache maintenance API must be added to cope with
latest ARM system requirements.

This patch adds flush_cache_louis() to the ARM kernel cache maintenance API.

This function cleans and invalidates all data cache levels up to the
Level of Unification Inner Shareable (LoUIS) and invalidates the instruction
cache for processors that support it (> v7).

This patch also creates an alias of the cache LoUIS function to flush_kern_all
for all processor versions prior to v7, so that the current cache flushing
behaviour is unchanged for those processors.

v7 cache maintenance code implements a cache LoUIS function that cleans and
invalidates the D-cache up to LoUIS and invalidates the I-cache, according
to the new API.

Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
2012-09-25 11:20:25 +01:00

535 lines
14 KiB
ArmAsm

/*
* linux/arch/arm/mm/proc-xsc3.S
*
* Original Author: Matthew Gilbert
* Current Maintainer: Lennert Buytenhek <buytenh@wantstofly.org>
*
* 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 original XScale code by Nicolas Pitre.
*/
#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 L1 I, L1 D and unified L2 cache.
*/
#define CACHELINESIZE 32
/*
* The size of the L1 D cache.
*/
#define CACHESIZE 32768
/*
* This macro is used to wait for a CP15 write and is needed when we
* have to ensure that the last operation to the coprocessor 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 and invalidates the entire L1 D cache.
*/
.macro clean_d_cache rd, rs
mov \rd, #0x1f00
orr \rd, \rd, #0x00e0
1: mcr p15, 0, \rd, c7, c14, 2 @ clean/invalidate L1 D line
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)
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
mov pc, lr
/*
* 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
.pushsection .idmap.text, "ax"
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, #0x3900 @ ..VIZ..S........
bic r1, r1, #0x0086 @ ........B....CA.
mcr p15, 0, r1, c1, c0, 0 @ ctrl register
mcr p15, 0, ip, c7, c7, 0 @ invalidate L1 caches and 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 and D TLBs
mov pc, r0
ENDPROC(cpu_xsc3_reset)
.popsection
/*
* 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.
*/
.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_icache_all()
*
* Unconditionally clean and invalidate the entire icache.
*/
ENTRY(xsc3_flush_icache_all)
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
mov pc, lr
ENDPROC(xsc3_flush_icache_all)
/*
* 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 L1 I cache and BTB
mcrne p15, 0, ip, c7, c10, 4 @ data write barrier
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 L1 I line
mcr p15, 0, r0, c7, c14, 1 @ clean/invalidate L1 D 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 @ data write barrier
mcrne p15, 0, ip, c7, c5, 4 @ prefetch flush
mov pc, lr
/*
* coherent_kern_range(start, end)
*
* Ensure coherency between the I cache and the D cache 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 L1 D line
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ invalidate L1 I cache and BTB
mcr p15, 0, r0, c7, c10, 4 @ data write barrier
mcr p15, 0, r0, c7, c5, 4 @ prefetch flush
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(xsc3_flush_kern_dcache_area)
add r1, r0, r1
1: mcr p15, 0, r0, c7, c14, 1 @ clean/invalidate L1 D line
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ invalidate L1 I cache and BTB
mcr p15, 0, r0, c7, c10, 4 @ data write barrier
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
*/
xsc3_dma_inv_range:
tst r0, #CACHELINESIZE - 1
bic r0, r0, #CACHELINESIZE - 1
mcrne p15, 0, r0, c7, c10, 1 @ clean L1 D line
tst r1, #CACHELINESIZE - 1
mcrne p15, 0, r1, c7, c10, 1 @ clean L1 D line
1: mcr p15, 0, r0, c7, c6, 1 @ invalidate L1 D line
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mcr p15, 0, r0, c7, c10, 4 @ data write barrier
mov pc, lr
/*
* dma_clean_range(start, end)
*
* Clean the specified virtual address range.
*
* - start - virtual start address
* - end - virtual end address
*/
xsc3_dma_clean_range:
bic r0, r0, #CACHELINESIZE - 1
1: mcr p15, 0, r0, c7, c10, 1 @ clean L1 D line
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mcr p15, 0, r0, c7, c10, 4 @ data write barrier
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 line
add r0, r0, #CACHELINESIZE
cmp r0, r1
blo 1b
mcr p15, 0, r0, c7, c10, 4 @ data write barrier
mov pc, lr
/*
* dma_map_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(xsc3_dma_map_area)
add r1, r1, r0
cmp r2, #DMA_TO_DEVICE
beq xsc3_dma_clean_range
bcs xsc3_dma_inv_range
b xsc3_dma_flush_range
ENDPROC(xsc3_dma_map_area)
/*
* dma_unmap_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(xsc3_dma_unmap_area)
mov pc, lr
ENDPROC(xsc3_dma_unmap_area)
.globl xsc3_flush_kern_cache_louis
.equ xsc3_flush_kern_cache_louis, xsc3_flush_kern_cache_all
@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
define_cache_functions xsc3
ENTRY(cpu_xsc3_dcache_clean_area)
1: mcr p15, 0, r0, c7, c10, 1 @ clean L1 D line
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 L1 I cache and BTB
mcr p15, 0, ip, c7, c10, 4 @ data write barrier
mcr p15, 0, ip, c7, c5, 4 @ prefetch flush
orr r0, r0, #0x18 @ cache the page table in L2
mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
mcr p15, 0, ip, c8, c7, 0 @ invalidate I and D TLBs
cpwait_ret lr, ip
/*
* cpu_xsc3_set_pte_ext(ptep, pte, ext)
*
* Set a PTE and flush it out
*/
cpu_xsc3_mt_table:
.long 0x00 @ L_PTE_MT_UNCACHED
.long PTE_EXT_TEX(1) @ L_PTE_MT_BUFFERABLE
.long PTE_EXT_TEX(5) | 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 0x00 @ L_PTE_MT_MINICACHE (not present)
.long PTE_EXT_TEX(5) | PTE_CACHEABLE | PTE_BUFFERABLE @ L_PTE_MT_WRITEALLOC (not present?)
.long 0x00 @ unused
.long PTE_EXT_TEX(1) @ L_PTE_MT_DEV_WC
.long 0x00 @ unused
.long PTE_CACHEABLE | PTE_BUFFERABLE @ L_PTE_MT_DEV_CACHED
.long PTE_EXT_TEX(2) @ L_PTE_MT_DEV_NONSHARED
.long 0x00 @ unused
.long 0x00 @ unused
.long 0x00 @ unused
.align 5
ENTRY(cpu_xsc3_set_pte_ext)
xscale_set_pte_ext_prologue
tst r1, #L_PTE_SHARED @ shared?
and r1, r1, #L_PTE_MT_MASK
adr ip, cpu_xsc3_mt_table
ldr ip, [ip, r1]
orrne r2, r2, #PTE_EXT_COHERENT @ interlock: mask in coherent bit
bic r2, r2, #0x0c @ clear old C,B bits
orr r2, r2, ip
xscale_set_pte_ext_epilogue
mov pc, lr
.ltorg
.align
.globl cpu_xsc3_suspend_size
.equ cpu_xsc3_suspend_size, 4 * 6
#ifdef CONFIG_PM_SLEEP
ENTRY(cpu_xsc3_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
ldmia sp!, {r4 - r9, pc}
ENDPROC(cpu_xsc3_do_suspend)
ENTRY(cpu_xsc3_do_resume)
ldmia r0, {r4 - r9} @ load cp regs
mov ip, #0
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, c7, c5, 4 @ flush prefetch buffer
mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
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
orr r1, r1, #0x18 @ cache the page table in L2
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_xsc3_do_resume)
#endif
__CPUINIT
.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 L1 caches and BTB
mcr p15, 0, ip, c7, c10, 4 @ data write barrier
mcr p15, 0, ip, c7, c5, 4 @ prefetch flush
mcr p15, 0, ip, c8, c7, 0 @ invalidate I and D TLBs
orr r4, r4, #0x18 @ cache the page table in L2
mcr p15, 0, r4, c2, c0, 0 @ load page table pointer
mov r0, #1 << 6 @ cp6 access for early sched_clock
mcr p15, 0, r0, c15, c1, 0 @ write CP access register
mrc p15, 0, r0, c1, c0, 1 @ get auxiliary control reg
and r0, r0, #2 @ preserve bit P bit setting
orr r0, r0, #(1 << 10) @ enable L2 for LLR cache
mcr p15, 0, r0, c1, c0, 1 @ set auxiliary control reg
adr r5, xsc3_crval
ldmia r5, {r5, r6}
#ifdef CONFIG_CACHE_XSC3L2
mrc p15, 1, r0, c0, c0, 1 @ get L2 present information
ands r0, r0, #0xf8
orrne r6, r6, #(1 << 26) @ enable L2 if present
#endif
mrc p15, 0, r0, c1, c0, 0 @ get control register
bic r0, r0, r5 @ ..V. ..R. .... ..A.
orr r0, r0, r6 @ ..VI Z..S .... .C.M (mmu)
@ ...I Z..S .... .... (uc)
mov pc, lr
.size __xsc3_setup, . - __xsc3_setup
.type xsc3_crval, #object
xsc3_crval:
crval clear=0x04002202, mmuset=0x00003905, ucset=0x00001900
__INITDATA
@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
define_processor_functions xsc3, dabort=v5t_early_abort, pabort=legacy_pabort, suspend=1
.section ".rodata"
string cpu_arch_name, "armv5te"
string cpu_elf_name, "v5"
string cpu_xsc3_name, "XScale-V3 based processor"
.align
.section ".proc.info.init", #alloc, #execinstr
.macro xsc3_proc_info name:req, cpu_val:req, cpu_mask:req
.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
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 __\name\()_proc_info, . - __\name\()_proc_info
.endm
xsc3_proc_info xsc3, 0x69056000, 0xffffe000
/* Note: PXA935 changed its implementor ID from Intel to Marvell */
xsc3_proc_info xsc3_pxa935, 0x56056000, 0xffffe000