--- /dev/null
+/*
+ * linux/arch/arm/mm/arm925.S: MMU functions for ARM925
+ *
+ * Copyright (C) 1999,2000 ARM Limited
+ * Copyright (C) 2000 Deep Blue Solutions Ltd.
+ * Copyright (C) 2002 RidgeRun, Inc.
+ * Copyright (C) 2002-2003 MontaVista Software, Inc.
+ *
+ * Update for Linux-2.6 and cache flush improvements
+ * Copyright (C) 2004 Nokia Corporation by Tony Lindgren <tony@atomide.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ *
+ * These are the low level assembler for performing cache and TLB
+ * functions on the arm925.
+ *
+ * CONFIG_CPU_ARM925_CPU_IDLE -> nohlt
+ *
+ * Some additional notes based on deciphering the TI TRM on OMAP-5910:
+ *
+ * NOTE1: The TI925T Configuration Register bit "D-cache clean and flush
+ * entry mode" must be 0 to flush the entries in both segments
+ * at once. This is the default value. See TRM 2-20 and 2-24 for
+ * more information.
+ *
+ * NOTE2: Default is the "D-cache clean and flush entry mode". It looks
+ * like the "Transparent mode" must be on for partial cache flushes
+ * to work in this mode. This mode only works with 16-bit external
+ * memory. See TRM 2-24 for more information.
+ *
+ * NOTE3: Write-back cache flushing seems to be flakey with devices using
+ * direct memory access, such as USB OHCI. The workaround is to use
+ * write-through cache with CONFIG_CPU_DCACHE_WRITETHROUGH (this is
+ * the default for OMAP-1510).
+ */
+
+#include <linux/linkage.h>
+#include <linux/config.h>
+#include <linux/init.h>
+#include <asm/assembler.h>
+#include <asm/pgtable.h>
+#include <asm/procinfo.h>
+#include <asm/hardware.h>
+#include <asm/page.h>
+#include <asm/ptrace.h>
+#include "proc-macros.S"
+
+/*
+ * The size of one data cache line.
+ */
+#define CACHE_DLINESIZE 16
+
+/*
+ * The number of data cache segments.
+ */
+#define CACHE_DSEGMENTS 2
+
+/*
+ * The number of lines in a cache segment.
+ */
+#define CACHE_DENTRIES 256
+
+/*
+ * This is the size at which it becomes more efficient to
+ * clean the whole cache, rather than using the individual
+ * cache line maintainence instructions.
+ */
+#define CACHE_DLIMIT 8192
+
+ .text
+/*
+ * cpu_arm925_proc_init()
+ */
+ENTRY(cpu_arm925_proc_init)
+ mov pc, lr
+
+/*
+ * cpu_arm925_proc_fin()
+ */
+ENTRY(cpu_arm925_proc_fin)
+ stmfd sp!, {lr}
+ mov ip, #PSR_F_BIT | PSR_I_BIT | SVC_MODE
+ msr cpsr_c, ip
+ bl arm925_flush_kern_cache_all
+ mrc p15, 0, r0, c1, c0, 0 @ ctrl register
+ bic r0, r0, #0x1000 @ ...i............
+ bic r0, r0, #0x000e @ ............wca.
+ mcr p15, 0, r0, c1, c0, 0 @ disable caches
+ ldmfd sp!, {pc}
+
+/*
+ * cpu_arm925_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
+ENTRY(cpu_arm925_reset)
+ /* Send software reset to MPU and DSP */
+ mov ip, #0xff000000
+ orr ip, ip, #0x00fe0000
+ orr ip, ip, #0x0000ce00
+ mov r4, #1
+ strh r4, [ip, #0x10]
+
+ mov ip, #0
+ mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
+ mcr p15, 0, ip, c7, c10, 4 @ drain WB
+ mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
+ mrc p15, 0, ip, c1, c0, 0 @ ctrl register
+ bic ip, ip, #0x000f @ ............wcam
+ bic ip, ip, #0x1100 @ ...i...s........
+ mcr p15, 0, ip, c1, c0, 0 @ ctrl register
+ mov pc, r0
+
+/*
+ * cpu_arm925_do_idle()
+ *
+ * Called with IRQs disabled
+ */
+ .align 10
+ENTRY(cpu_arm925_do_idle)
+ mov r0, #0
+ mrc p15, 0, r1, c1, c0, 0 @ Read control register
+ mcr p15, 0, r0, c7, c10, 4 @ Drain write buffer
+ bic r2, r1, #1 << 12
+ mcr p15, 0, r2, c1, c0, 0 @ Disable I cache
+ mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
+ mcr p15, 0, r1, c1, c0, 0 @ Restore ICache enable
+ mov pc, lr
+
+/*
+ * flush_user_cache_all()
+ *
+ * Clean and invalidate all cache entries in a particular
+ * address space.
+ */
+ENTRY(arm925_flush_user_cache_all)
+ /* FALLTHROUGH */
+
+/*
+ * flush_kern_cache_all()
+ *
+ * Clean and invalidate the entire cache.
+ */
+ENTRY(arm925_flush_kern_cache_all)
+ mov r2, #VM_EXEC
+ mov ip, #0
+__flush_whole_cache:
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
+#else
+ /* Flush entries in both segments at once, see NOTE1 above */
+ mov r3, #(CACHE_DENTRIES - 1) << 4 @ 256 entries in segment
+2: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index
+ subs r3, r3, #1 << 4
+ bcs 2b @ entries 255 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
+
+/*
+ * flush_user_cache_range(start, end, flags)
+ *
+ * Clean and invalidate a range of cache entries in the
+ * specified address range.
+ *
+ * - start - start address (inclusive)
+ * - end - end address (exclusive)
+ * - flags - vm_flags describing address space
+ */
+ENTRY(arm925_flush_user_cache_range)
+ mov ip, #0
+ sub r3, r1, r0 @ calculate total size
+ cmp r3, #CACHE_DLIMIT
+ bgt __flush_whole_cache
+1: tst r2, #VM_EXEC
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
+ mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+ mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
+ mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+#else
+ mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D entry
+ mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+ mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D entry
+ mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+#endif
+ cmp r0, r1
+ blo 1b
+ tst r2, #VM_EXEC
+ 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(arm925_coherent_kern_range)
+ bic r0, r0, #CACHE_DLINESIZE - 1
+1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+ mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+/*
+ * flush_kern_dcache_page(void *page)
+ *
+ * Ensure no D cache aliasing occurs, either with itself or
+ * the I cache
+ *
+ * - addr - page aligned address
+ */
+ENTRY(arm925_flush_kern_dcache_page)
+ add r1, r0, #PAGE_SZ
+1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mov r0, #0
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
+ mcr p15, 0, r0, 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
+ *
+ * (same as v4wb)
+ */
+ENTRY(arm925_dma_inv_range)
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+ tst 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
+#endif
+ bic r0, r0, #CACHE_DLINESIZE - 1
+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 WB
+ mov pc, lr
+
+/*
+ * dma_clean_range(start, end)
+ *
+ * Clean the specified virtual address range.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ *
+ * (same as v4wb)
+ */
+ENTRY(arm925_dma_clean_range)
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+ 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
+#endif
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ 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(arm925_dma_flush_range)
+ bic r0, r0, #CACHE_DLINESIZE - 1
+1:
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
+#else
+ mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+#endif
+ add r0, r0, #CACHE_DLINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+ENTRY(arm925_cache_fns)
+ .long arm925_flush_kern_cache_all
+ .long arm925_flush_user_cache_all
+ .long arm925_flush_user_cache_range
+ .long arm925_coherent_kern_range
+ .long arm925_flush_kern_dcache_page
+ .long arm925_dma_inv_range
+ .long arm925_dma_clean_range
+ .long arm925_dma_flush_range
+
+ENTRY(cpu_arm925_dcache_clean_area)
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+ add r0, r0, #CACHE_DLINESIZE
+ subs r1, r1, #CACHE_DLINESIZE
+ bhi 1b
+#endif
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+/* =============================== PageTable ============================== */
+
+/*
+ * cpu_arm925_switch_mm(pgd)
+ *
+ * Set the translation base pointer to be as described by pgd.
+ *
+ * pgd: new page tables
+ */
+ .align 5
+ENTRY(cpu_arm925_switch_mm)
+ mov ip, #0
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
+#else
+ /* Flush entries in bothe segments at once, see NOTE1 above */
+ mov r3, #(CACHE_DENTRIES - 1) << 4 @ 256 entries in segment
+2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index
+ subs r3, r3, #1 << 4
+ bcs 2b @ entries 255 to 0
+#endif
+ mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
+ mcr p15, 0, ip, c7, c10, 4 @ drain WB
+ mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
+ mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
+ mov pc, lr
+
+/*
+ * cpu_arm925_set_pte(ptep, pte)
+ *
+ * Set a PTE and flush it out
+ */
+ .align 5
+ENTRY(cpu_arm925_set_pte)
+ str r1, [r0], #-2048 @ linux version
+
+ eor r1, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
+
+ bic r2, r1, #PTE_SMALL_AP_MASK
+ bic r2, r2, #PTE_TYPE_MASK
+ orr r2, r2, #PTE_TYPE_SMALL
+
+ tst r1, #L_PTE_USER @ User?
+ orrne r2, r2, #PTE_SMALL_AP_URO_SRW
+
+ tst r1, #L_PTE_WRITE | L_PTE_DIRTY @ Write and Dirty?
+ orreq r2, r2, #PTE_SMALL_AP_UNO_SRW
+
+ tst r1, #L_PTE_PRESENT | L_PTE_YOUNG @ Present and Young?
+ movne r2, #0
+
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+ eor r3, r2, #0x0a @ C & small page?
+ tst r3, #0x0b
+ biceq r2, r2, #4
+#endif
+ str r2, [r0] @ hardware version
+ mov r0, r0
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mcr p15, 0, r0, c7, c10, 1 @ clean D entry
+#endif
+ mcr p15, 0, r0, c7, c10, 4 @ drain WB
+ mov pc, lr
+
+ __INIT
+
+ .type __arm925_setup, #function
+__arm925_setup:
+ mov r0, #0
+#if defined(CONFIG_CPU_ICACHE_STREAMING_DISABLE)
+ orr r0,r0,#1 << 7
+#endif
+
+ /* Transparent on, D-cache clean & flush mode. See NOTE2 above */
+ orr r0,r0,#1 << 1 @ transparent mode on
+ mcr p15, 0, r0, c15, c1, 0 @ write TI config register
+
+ mov r0, #0
+ mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
+ mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
+ mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
+ mcr p15, 0, r4, c2, c0 @ load page table pointer
+
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+ mov r0, #4 @ disable write-back on caches explicitly
+ mcr p15, 7, r0, c15, c0, 0
+#endif
+
+ mov r0, #0x1f @ Domains 0, 1 = client
+ mcr p15, 0, r0, c3, c0 @ load domain access register
+ mrc p15, 0, r0, c1, c0 @ get control register v4
+/*
+ * Clear out 'unwanted' bits (then put them in if we need them)
+ */
+ @ VI ZFRS BLDP WCAM
+ bic r0, r0, #0x0e00
+ bic r0, r0, #0x0002
+ bic r0, r0, #0x000c
+ bic r0, r0, #0x1000 @ ...0 000. .... 000.
+/*
+ * Turn on what we want
+ */
+ orr r0, r0, #0x0031
+ orr r0, r0, #0x2100 @ ..1. ...1 ..11 ...1
+
+ /* Writebuffer on */
+ orr r0, r0, #0x0008 @ .... .... .... 1...
+
+#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
+ orr r0, r0, #0x4000 @ .1.. .... .... ....
+#endif
+#ifndef CONFIG_CPU_DCACHE_DISABLE
+ orr r0, r0, #0x0004 @ .... .... .... .1..
+#endif
+#ifndef CONFIG_CPU_ICACHE_DISABLE
+ orr r0, r0, #0x1000 @ ...1 .... .... ....
+#endif
+ mov pc, lr
+ .size __arm925_setup, . - __arm925_setup
+
+ __INITDATA
+
+/*
+ * Purpose : Function pointers used to access above functions - all calls
+ * come through these
+ */
+ .type arm925_processor_functions, #object
+arm925_processor_functions:
+ .word v4t_early_abort
+ .word cpu_arm925_proc_init
+ .word cpu_arm925_proc_fin
+ .word cpu_arm925_reset
+ .word cpu_arm925_do_idle
+ .word cpu_arm925_dcache_clean_area
+ .word cpu_arm925_switch_mm
+ .word cpu_arm925_set_pte
+ .size arm925_processor_functions, . - arm925_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_arm925_name, #object
+cpu_arm925_name:
+ .ascii "ARM925T"
+#ifndef CONFIG_CPU_ICACHE_DISABLE
+ .ascii "i"
+#endif
+#ifndef CONFIG_CPU_DCACHE_DISABLE
+ .ascii "d"
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+ .ascii "(wt)"
+#else
+ .ascii "(wb)"
+#endif
+#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
+ .ascii "RR"
+#endif
+#endif
+ .ascii "\0"
+ .size cpu_arm925_name, . - cpu_arm925_name
+
+ .align
+
+ .section ".proc.info", #alloc, #execinstr
+
+ .type __arm925_proc_info,#object
+__arm925_proc_info:
+ .long 0x54029250
+ .long 0xfffffff0
+ .long 0x00000c12 @ mmuflags
+ b __arm925_setup
+ .long cpu_arch_name
+ .long cpu_elf_name
+ .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
+ .long cpu_arm925_name
+ .long arm925_processor_functions
+ .long v4wbi_tlb_fns
+ .long v4wb_user_fns
+ .long arm925_cache_fns
+ .size __arm925_proc_info, . - __arm925_proc_info
+
+ .type __arm915_proc_info,#object
+__arm915_proc_info:
+ .long 0x54029150
+ .long 0xfffffff0
+ .long 0x00000c12 @ mmuflags
+ b __arm925_setup
+ .long cpu_arch_name
+ .long cpu_elf_name
+ .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
+ .long cpu_arm925_name
+ .long arm925_processor_functions
+ .long v4wbi_tlb_fns
+ .long v4wb_user_fns
+ .long arm925_cache_fns
+ .size __arm925_proc_info, . - __arm925_proc_info
projects / linux / commitdiff