/* * 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 mov pc, 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 mov pc, 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 mov pc, 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 mov pc, 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 mov pc, 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 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(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 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(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 mov pc, 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 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(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 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 */ 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 mov pc, 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 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(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 mov pc, 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) mov pc, 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 mov pc, 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 mov pc, 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, c1, 0 @ 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, c1, 0 @ auxiliary control reg mov r0, r9 @ control register b cpu_resume_mmu ENDPROC(cpu_xscale_do_resume) #endif __CPUINIT .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 mov pc, 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, #execinstr .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 b __xscale_setup .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