--- /dev/null
+/*
+ * Cache-handling routined for MIPS CPUs
+ *
+ * Copyright (c) 2003 Wolfgang Denk <wd@denx.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <asm-offsets.h>
+#include <config.h>
+#include <asm/asm.h>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+#include <asm/addrspace.h>
+#include <asm/cacheops.h>
+
+#define RA t9
+
+/*
+ * 16kB is the maximum size of instruction and data caches on MIPS 4K,
+ * 64kB is on 4KE, 24K, 5K, etc. Set bigger size for convenience.
+ *
+ * Note that the above size is the maximum size of primary cache. U-Boot
+ * doesn't have L2 cache support for now.
+ */
+#define MIPS_MAX_CACHE_SIZE 0x10000
+
+#define INDEX_BASE CKSEG0
+
+ .macro cache_op op addr
+ .set push
+ .set noreorder
+ .set mips3
+ cache \op, 0(\addr)
+ .set pop
+ .endm
+
+ .macro f_fill64 dst, offset, val
+ LONG_S \val, (\offset + 0 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 1 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 2 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 3 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 4 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 5 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 6 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 7 * LONGSIZE)(\dst)
+#if LONGSIZE == 4
+ LONG_S \val, (\offset + 8 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 9 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 10 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 11 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 12 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 13 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 14 * LONGSIZE)(\dst)
+ LONG_S \val, (\offset + 15 * LONGSIZE)(\dst)
+#endif
+ .endm
+
+/*
+ * mips_init_icache(uint PRId, ulong icache_size, unchar icache_linesz)
+ */
+LEAF(mips_init_icache)
+ blez a1, 9f
+ mtc0 zero, CP0_TAGLO
+ /* clear tag to invalidate */
+ PTR_LI t0, INDEX_BASE
+ PTR_ADDU t1, t0, a1
+1: cache_op INDEX_STORE_TAG_I t0
+ PTR_ADDU t0, a2
+ bne t0, t1, 1b
+ /* fill once, so data field parity is correct */
+ PTR_LI t0, INDEX_BASE
+2: cache_op FILL t0
+ PTR_ADDU t0, a2
+ bne t0, t1, 2b
+ /* invalidate again - prudent but not strictly neccessary */
+ PTR_LI t0, INDEX_BASE
+1: cache_op INDEX_STORE_TAG_I t0
+ PTR_ADDU t0, a2
+ bne t0, t1, 1b
+9: jr ra
+ END(mips_init_icache)
+
+/*
+ * mips_init_dcache(uint PRId, ulong dcache_size, unchar dcache_linesz)
+ */
+LEAF(mips_init_dcache)
+ blez a1, 9f
+ mtc0 zero, CP0_TAGLO
+ /* clear all tags */
+ PTR_LI t0, INDEX_BASE
+ PTR_ADDU t1, t0, a1
+1: cache_op INDEX_STORE_TAG_D t0
+ PTR_ADDU t0, a2
+ bne t0, t1, 1b
+ /* load from each line (in cached space) */
+ PTR_LI t0, INDEX_BASE
+2: LONG_L zero, 0(t0)
+ PTR_ADDU t0, a2
+ bne t0, t1, 2b
+ /* clear all tags */
+ PTR_LI t0, INDEX_BASE
+1: cache_op INDEX_STORE_TAG_D t0
+ PTR_ADDU t0, a2
+ bne t0, t1, 1b
+9: jr ra
+ END(mips_init_dcache)
+
+/*
+ * 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
+ *
+ */
+NESTED(mips_cache_reset, 0, ra)
+ move RA, ra
+ li t2, CONFIG_SYS_ICACHE_SIZE
+ li t3, CONFIG_SYS_DCACHE_SIZE
+ li t8, CONFIG_SYS_CACHELINE_SIZE
+
+ li v0, MIPS_MAX_CACHE_SIZE
+
+ /*
+ * Now clear that much memory starting from zero.
+ */
+ PTR_LI a0, CKSEG1
+ PTR_ADDU a1, a0, v0
+2: PTR_ADDIU a0, 64
+ f_fill64 a0, -64, zero
+ bne a0, a1, 2b
+
+ /*
+ * 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.
+ */
+
+ /*
+ * Initialize the I-cache first,
+ */
+ move a1, t2
+ move a2, t8
+ PTR_LA v1, mips_init_icache
+ jalr v1
+
+ /*
+ * then initialize D-cache.
+ */
+ move a1, t3
+ move a2, t8
+ PTR_LA v1, mips_init_dcache
+ jalr v1
+
+ jr RA
+ END(mips_cache_reset)
+
+/*
+ * dcache_status - get cache status
+ *
+ * RETURNS: 0 - cache disabled; 1 - cache enabled
+ *
+ */
+LEAF(dcache_status)
+ mfc0 t0, CP0_CONFIG
+ li t1, CONF_CM_UNCACHED
+ andi t0, t0, CONF_CM_CMASK
+ move v0, zero
+ beq t0, t1, 2f
+ li v0, 1
+2: jr ra
+ END(dcache_status)
+
+/*
+ * dcache_disable - disable cache
+ *
+ * RETURNS: N/A
+ *
+ */
+LEAF(dcache_disable)
+ mfc0 t0, CP0_CONFIG
+ li t1, -8
+ and t0, t0, t1
+ ori t0, t0, CONF_CM_UNCACHED
+ mtc0 t0, CP0_CONFIG
+ jr ra
+ END(dcache_disable)
+
+/*
+ * dcache_enable - enable cache
+ *
+ * RETURNS: N/A
+ *
+ */
+LEAF(dcache_enable)
+ mfc0 t0, CP0_CONFIG
+ ori t0, CONF_CM_CMASK
+ xori t0, CONF_CM_CMASK
+ ori t0, CONF_CM_CACHABLE_NONCOHERENT
+ mtc0 t0, CP0_CONFIG
+ jr ra
+ END(dcache_enable)
Code Review / kvmfornfv.git / blobdiff