--- /dev/null
+/*
+ * linux/arch/arm/mm/proc-xsc3.S
+ *
+ * Original Author: Matthew Gilbert
+ * Current Maintainer: Deepak Saxena <dsaxena@plexity.net>
+ *
+ * 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 orignal XScale code by Nicolas Pitre
+ */
+
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/assembler.h>
+#include <asm/procinfo.h>
+#include <asm/hardware.h>
+#include <asm/pgtable.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
+
+/*
+ * Run with L2 enabled.
+ */
+#define L2_CACHE_ENABLE 1
+
+/*
+ * Enable the Branch Target Buffer (can cause crashes, see erratum #42.)
+ */
+#define BTB_ENABLE 0
+
+/*
+ * 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_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 & invalidates the entire xsc3 dcache by set & way.
+ */
+
+ .macro clean_d_cache rd, rs
+ mov \rd, #0x1f00
+ orr \rd, \rd, #0x00e0
+1: mcr p15, 0, \rd, c7, c14, 2 @ clean/inv set/way
+ 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)
+ str lr, [sp, #-4]!
+ mov r0, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
+ msr cpsr_c, r0
+ bl xsc3_flush_kern_cache_all @ clean caches
+ 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
+ ldr pc, [sp], #4
+
+/*
+ * 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
+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, #0x0086 @ ........B....CA.
+ bic r1, r1, #0x3900 @ ..VIZ..S........
+ mcr p15, 0, r1, c1, c0, 0 @ ctrl register
+ mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches & 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 & D TLBs
+ mov pc, r0
+
+/*
+ * 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.
+
+ MMG: Come back to this one.
+ */
+ .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_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 I cache & BTB
+ mcrne p15, 0, ip, c7, c10, 4 @ Drain Write Buffer
+ 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 I cache line
+ mcr p15, 0, r0, c7, c14, 1 @ Clean/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 Buffer
+ mcrne p15, 0, ip, c7, c5, 4 @ Prefetch Flush
+ 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(xsc3_coherent_kern_range)
+/* FALLTHROUGH */
+ENTRY(xsc3_coherent_user_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 Buffer
+ mcr p15, 0, r0, c7, c5, 4 @ Prefetch Flush
+ 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(xsc3_flush_kern_dcache_page)
+ add r1, r0, #PAGE_SZ
+1: mcr p15, 0, r0, c7, c14, 1 @ Clean/Invalidate D Cache line
+ 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 Buffer
+ 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
+ */
+ENTRY(xsc3_dma_inv_range)
+ tst r0, #CACHELINESIZE - 1
+ bic r0, r0, #CACHELINESIZE - 1
+ mcrne p15, 0, r0, c7, c10, 1 @ clean L1 D entry
+ mcrne p15, 1, r0, c7, c11, 1 @ clean L2 D entry
+ tst r1, #CACHELINESIZE - 1
+ mcrne p15, 0, r1, c7, c10, 1 @ clean L1 D entry
+ mcrne p15, 1, r1, c7, c11, 1 @ clean L2 D entry
+1: mcr p15, 0, r0, c7, c6, 1 @ invalidate L1 D entry
+ mcr p15, 1, r0, c7, c7, 1 @ Invalidate L2 D cache line
+ add r0, r0, #CACHELINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer
+ mov pc, lr
+
+/*
+ * dma_clean_range(start, end)
+ *
+ * Clean the specified virtual address range.
+ *
+ * - start - virtual start address
+ * - end - virtual end address
+ */
+ENTRY(xsc3_dma_clean_range)
+ bic r0, r0, #CACHELINESIZE - 1
+1: mcr p15, 0, r0, c7, c10, 1 @ clean L1 D entry
+ mcr p15, 1, r0, c7, c11, 1 @ clean L2 D entry
+ add r0, r0, #CACHELINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ Drain Write 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(xsc3_dma_flush_range)
+ bic r0, r0, #CACHELINESIZE - 1
+1: mcr p15, 0, r0, c7, c14, 1 @ Clean/invalidate L1 D cache line
+ mcr p15, 1, r0, c7, c11, 1 @ Clean L2 D cache line
+ mcr p15, 1, r0, c7, c7, 1 @ Invalidate L2 D cache line
+ add r0, r0, #CACHELINESIZE
+ cmp r0, r1
+ blo 1b
+ mcr p15, 0, r0, c7, c10, 4 @ Drain Write Buffer
+ mov pc, lr
+
+ENTRY(xsc3_cache_fns)
+ .long xsc3_flush_kern_cache_all
+ .long xsc3_flush_user_cache_all
+ .long xsc3_flush_user_cache_range
+ .long xsc3_coherent_kern_range
+ .long xsc3_coherent_user_range
+ .long xsc3_flush_kern_dcache_page
+ .long xsc3_dma_inv_range
+ .long xsc3_dma_clean_range
+ .long xsc3_dma_flush_range
+
+ENTRY(cpu_xsc3_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_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 I cache & BTB
+ mcr p15, 0, ip, c7, c10, 4 @ Drain Write Buffer
+ mcr p15, 0, ip, c7, c5, 4 @ Prefetch Flush
+#ifdef L2_CACHE_ENABLE
+ orr r0, r0, #0x18 @ cache the page table in L2
+#endif
+ 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_xsc3_set_pte(ptep, pte)
+ *
+ * Set a PTE and flush it out
+ *
+ */
+ .align 5
+ENTRY(cpu_xsc3_set_pte)
+ str r1, [r0], #-2048 @ linux version
+
+ bic r2, r1, #0xff0
+ orr r2, r2, #PTE_TYPE_EXT @ extended page
+
+ eor r3, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
+
+ tst r3, #L_PTE_USER @ User?
+ orrne r2, r2, #PTE_EXT_AP_URO_SRW @ yes -> user r/o, system r/w
+
+ tst r3, #L_PTE_WRITE | L_PTE_DIRTY @ Write and Dirty?
+ orreq r2, r2, #PTE_EXT_AP_UNO_SRW @ yes -> user n/a, system r/w
+ @ combined with user -> user r/w
+
+#if L2_CACHE_ENABLE
+ @ If its cacheable it needs to be in L2 also.
+ eor ip, r1, #L_PTE_CACHEABLE
+ tst ip, #L_PTE_CACHEABLE
+ orreq r2, r2, #PTE_EXT_TEX(0x5)
+#endif
+
+ tst r3, #L_PTE_PRESENT | L_PTE_YOUNG @ Present and Young?
+ movne r2, #0 @ no -> fault
+
+ str r2, [r0] @ hardware version
+ mov ip, #0
+ mcr p15, 0, r0, c7, c10, 1 @ Clean D cache line mcr
+ mcr p15, 0, ip, c7, c10, 4 @ Drain Write Buffer
+ mov pc, lr
+
+ .ltorg
+
+ .align
+
+ __INIT
+
+ .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 I, D caches & BTB
+ mcr p15, 0, ip, c7, c10, 4 @ Drain Write Buffer
+ mcr p15, 0, ip, c7, c5, 4 @ Prefetch Flush
+ mcr p15, 0, ip, c8, c7, 0 @ invalidate I, D TLBs
+#if L2_CACHE_ENABLE
+ orr r4, r4, #0x18 @ cache the page table in L2
+#endif
+ mcr p15, 0, r4, c2, c0, 0 @ load page table pointer
+ mov r0, #1 @ Allow access to CP0 and CP13
+ orr r0, r0, #1 << 13 @ Its undefined whether this
+ mcr p15, 0, r0, c15, c1, 0 @ affects USR or SVC modes
+ mrc p15, 0, r0, c1, c0, 1 @ get auxiliary control reg
+ and r0, r0, #2 @ preserve bit P bit setting
+#if L2_CACHE_ENABLE
+ orr r0, r0, #(1 << 10) @ enable L2 for LLR cache
+#endif
+ mcr p15, 0, r0, c1, c0, 1 @ set auxiliary control reg
+ mrc p15, 0, r0, c1, c0, 0 @ get control register
+ bic r0, r0, #0x0200 @ .... ..R. .... ....
+ bic r0, r0, #0x0002 @ .... .... .... ..A.
+ orr r0, r0, #0x0005 @ .... .... .... .C.M
+#if BTB_ENABLE
+ orr r0, r0, #0x3900 @ ..VI Z..S .... ....
+#else
+ orr r0, r0, #0x3100 @ ..VI ...S .... ....
+#endif
+#if L2_CACHE_ENABLE
+ orr r0, r0, #0x4000000 @ L2 enable
+#endif
+ mov pc, lr
+
+ .size __xsc3_setup, . - __xsc3_setup
+
+ __INITDATA
+
+/*
+ * Purpose : Function pointers used to access above functions - all calls
+ * come through these
+ */
+
+ .type xsc3_processor_functions, #object
+ENTRY(xsc3_processor_functions)
+ .word v5t_early_abort
+ .word cpu_xsc3_proc_init
+ .word cpu_xsc3_proc_fin
+ .word cpu_xsc3_reset
+ .word cpu_xsc3_do_idle
+ .word cpu_xsc3_dcache_clean_area
+ .word cpu_xsc3_switch_mm
+ .word cpu_xsc3_set_pte
+ .size xsc3_processor_functions, . - xsc3_processor_functions
+
+ .section ".rodata"
+
+ .type cpu_arch_name, #object
+cpu_arch_name:
+ .asciz "armv5te"
+ .size cpu_arch_name, . - cpu_arch_name
+
+ .type cpu_elf_name, #object
+cpu_elf_name:
+ .asciz "v5"
+ .size cpu_elf_name, . - cpu_elf_name
+
+ .type cpu_xsc3_name, #object
+cpu_xsc3_name:
+ .asciz "XScale-Core3"
+ .size cpu_xsc3_name, . - cpu_xsc3_name
+
+ .align
+
+ .section ".proc.info.init", #alloc, #execinstr
+
+ .type __xsc3_proc_info,#object
+__xsc3_proc_info:
+ .long 0x69056000
+ .long 0xffffe000
+ .long 0x00000c0e
+ 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 __xsc3_proc_info, . - __xsc3_proc_info