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+/*
+ * Cache-handling routined for MIPS 4K CPUs
+ *
+ * Copyright (c) 2003 Wolfgang Denk <wd@denx.de>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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
+ */
+
+
+#include <config.h>
+#include <version.h>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+#include <asm/addrspace.h>
+#include <asm/cacheops.h>
+
+
+ /* 16KB is the maximum size of instruction and data caches on
+ * MIPS 4K.
+ */
+#define MIPS_MAX_CACHE_SIZE 0x4000
+
+
+/*
+ * cacheop macro to automate cache operations
+ * first some helpers...
+ */
+#define _mincache(size, maxsize) \
+ bltu size,maxsize,9f ; \
+ move size,maxsize ; \
+9:
+
+#define _align(minaddr, maxaddr, linesize) \
+ .set noat ; \
+ subu AT,linesize,1 ; \
+ not AT ; \
+ and minaddr,AT ; \
+ addu maxaddr,-1 ; \
+ and maxaddr,AT ; \
+ .set at
+
+/* general operations */
+#define doop1(op1) \
+ cache op1,0(a0)
+#define doop2(op1, op2) \
+ cache op1,0(a0) ; \
+ nop ; \
+ cache op2,0(a0)
+
+/* specials for cache initialisation */
+#define doop1lw(op1) \
+ lw zero,0(a0)
+#define doop1lw1(op1) \
+ cache op1,0(a0) ; \
+ lw zero,0(a0) ; \
+ cache op1,0(a0)
+#define doop121(op1,op2) \
+ cache op1,0(a0) ; \
+ nop; \
+ cache op2,0(a0) ; \
+ nop; \
+ cache op1,0(a0)
+
+#define _oploopn(minaddr, maxaddr, linesize, tag, ops) \
+ .set noreorder ; \
+10: doop##tag##ops ; \
+ bne minaddr,maxaddr,10b ; \
+ add minaddr,linesize ; \
+ .set reorder
+
+/* finally the cache operation macros */
+#define vcacheopn(kva, n, cacheSize, cacheLineSize, tag, ops) \
+ blez n,11f ; \
+ addu n,kva ; \
+ _align(kva, n, cacheLineSize) ; \
+ _oploopn(kva, n, cacheLineSize, tag, ops) ; \
+11:
+
+#define icacheopn(kva, n, cacheSize, cacheLineSize, tag, ops) \
+ _mincache(n, cacheSize); \
+ blez n,11f ; \
+ addu n,kva ; \
+ _align(kva, n, cacheLineSize) ; \
+ _oploopn(kva, n, cacheLineSize, tag, ops) ; \
+11:
+
+#define vcacheop(kva, n, cacheSize, cacheLineSize, op) \
+ vcacheopn(kva, n, cacheSize, cacheLineSize, 1, (op))
+
+#define icacheop(kva, n, cacheSize, cacheLineSize, op) \
+ icacheopn(kva, n, cacheSize, cacheLineSize, 1, (op))
+
+/*******************************************************************************
+*
+* mips_cache_reset - low level initialisation of the primary caches
+*
+* This routine initialises the primary caches to ensure that they
+* have good parity. It must be called by the ROM before any cached locations
+* are used to prevent the possibility of data with bad parity being written to
+* memory.
+* To initialise the instruction cache it is essential that a source of data
+* with good parity is available. This routine
+* will initialise an area of memory starting at location zero to be used as
+* a source of parity.
+*
+* RETURNS: N/A
+*
+*/
+ .globl mips_cache_reset
+ .ent mips_cache_reset
+mips_cache_reset:
+
+ li t2, CFG_ICACHE_SIZE
+ li t3, CFG_DCACHE_SIZE
+ li t4, CFG_CACHELINE_SIZE
+ move t5, t4
+
+
+ li v0, MIPS_MAX_CACHE_SIZE
+
+ /* Now clear that much memory starting from zero.
+ */
+
+ li a0, KSEG1
+ addu a1, a0, v0
+
+2: sw zero, 0(a0)
+ sw zero, 4(a0)
+ sw zero, 8(a0)
+ sw zero, 12(a0)
+ sw zero, 16(a0)
+ sw zero, 20(a0)
+ sw zero, 24(a0)
+ sw zero, 28(a0)
+ addu a0, 32
+ bltu a0, a1, 2b
+
+ /* Set invalid tag.
+ */
+
+ mtc0 zero, CP0_TAGLO
+
+ /*
+ * The caches are probably in an indeterminate state,
+ * so we force good parity into them by doing an
+ * invalidate, load/fill, invalidate for each line.
+ */
+
+ /* Assume bottom of RAM will generate good parity for the cache.
+ */
+
+ li a0, K0BASE
+ move a2, t2 # icacheSize
+ move a3, t4 # icacheLineSize
+ move a1, a2
+ icacheopn(a0,a1,a2,a3,121,(Index_Store_Tag_I,Fill))
+
+ /* To support Orion/R4600, we initialise the data cache in 3 passes.
+ */
+
+ /* 1: initialise dcache tags.
+ */
+
+ li a0, K0BASE
+ move a2, t3 # dcacheSize
+ move a3, t5 # dcacheLineSize
+ move a1, a2
+ icacheop(a0,a1,a2,a3,Index_Store_Tag_D)
+
+ /* 2: fill dcache.
+ */
+
+ li a0, K0BASE
+ move a2, t3 # dcacheSize
+ move a3, t5 # dcacheLineSize
+ move a1, a2
+ icacheopn(a0,a1,a2,a3,1lw,(dummy))
+
+ /* 3: clear dcache tags.
+ */
+
+ li a0, K0BASE
+ move a2, t3 # dcacheSize
+ move a3, t5 # dcacheLineSize
+ move a1, a2
+ icacheop(a0,a1,a2,a3,Index_Store_Tag_D)
+
+ j ra
+ .end mips_cache_reset
+
+
+/*******************************************************************************
+*
+* dcache_status - get cache status
+*
+* RETURNS: 0 - cache disabled; 1 - cache enabled
+*
+*/
+ .globl dcache_status
+ .ent dcache_status
+dcache_status:
+
+ mfc0 v0, CP0_CONFIG
+ andi v0, v0, 1
+ j ra
+
+ .end dcache_status
+
+/*******************************************************************************
+*
+* dcache_disable - disable cache
+*
+* RETURNS: N/A
+*
+*/
+ .globl dcache_disable
+ .ent dcache_disable
+dcache_disable:
+
+ mfc0 t0, CP0_CONFIG
+ li t1, -8
+ and t0, t0, t1
+ ori t0, t0, CONF_CM_UNCACHED
+ mtc0 t0, CP0_CONFIG
+ j ra
+
+ .end dcache_disable
+
+
+/*******************************************************************************
+*
+* mips_cache_lock - lock RAM area pointed to by a0 in cache.
+*
+* RETURNS: N/A
+*
+*/
+ .globl mips_cache_lock
+ .ent mips_cache_lock
+mips_cache_lock:
+ li a1, K0BASE - CFG_DCACHE_SIZE
+ addu a0, a1
+ li a2, CFG_DCACHE_SIZE
+ li a3, CFG_CACHELINE_SIZE
+ move a1, a2
+ icacheop(a0,a1,a2,a3,0x1d)
+
+ j ra
+ .end mips_cache_lock
+