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-rw-r--r--arch/mips/mm/sc-mips.c141
1 files changed, 141 insertions, 0 deletions
diff --git a/arch/mips/mm/sc-mips.c b/arch/mips/mm/sc-mips.c
new file mode 100644
index 00000000000..d3f92a9e831
--- /dev/null
+++ b/arch/mips/mm/sc-mips.c
@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2006 Chris Dearman (chris@mips.com),
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+
+#include <asm/mipsregs.h>
+#include <asm/bcache.h>
+#include <asm/cacheops.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/mmu_context.h>
+#include <asm/r4kcache.h>
+
+/*
+ * MIPS32/MIPS64 L2 cache handling
+ */
+
+/*
+ * Writeback and invalidate the secondary cache before DMA.
+ */
+static void mips_sc_wback_inv(unsigned long addr, unsigned long size)
+{
+ unsigned long sc_lsize = cpu_scache_line_size();
+ unsigned long end, a;
+
+ pr_debug("mips_sc_wback_inv[%08lx,%08lx]", addr, size);
+
+ /* Catch bad driver code */
+ BUG_ON(size == 0);
+
+ a = addr & ~(sc_lsize - 1);
+ end = (addr + size - 1) & ~(sc_lsize - 1);
+ while (1) {
+ flush_scache_line(a); /* Hit_Writeback_Inv_SD */
+ if (a == end)
+ break;
+ a += sc_lsize;
+ }
+}
+
+/*
+ * Invalidate the secondary cache before DMA.
+ */
+static void mips_sc_inv(unsigned long addr, unsigned long size)
+{
+ unsigned long sc_lsize = cpu_scache_line_size();
+ unsigned long end, a;
+
+ pr_debug("mips_sc_inv[%08lx,%08lx]", addr, size);
+
+ /* Catch bad driver code */
+ BUG_ON(size == 0);
+
+ a = addr & ~(sc_lsize - 1);
+ end = (addr + size - 1) & ~(sc_lsize - 1);
+ while (1) {
+ invalidate_scache_line(a); /* Hit_Invalidate_SD */
+ if (a == end)
+ break;
+ a += sc_lsize;
+ }
+}
+
+static void mips_sc_enable(void)
+{
+ /* L2 cache is permanently enabled */
+}
+
+static void mips_sc_disable(void)
+{
+ /* L2 cache is permanently enabled */
+}
+
+static struct bcache_ops mips_sc_ops = {
+ .bc_enable = mips_sc_enable,
+ .bc_disable = mips_sc_disable,
+ .bc_wback_inv = mips_sc_wback_inv,
+ .bc_inv = mips_sc_inv
+};
+
+static inline int __init mips_sc_probe(void)
+{
+ struct cpuinfo_mips *c = &current_cpu_data;
+ unsigned int config1, config2;
+ unsigned int tmp;
+
+ /* Mark as not present until probe completed */
+ c->scache.flags |= MIPS_CACHE_NOT_PRESENT;
+
+ /* Ignore anything but MIPSxx processors */
+ if (c->isa_level != MIPS_CPU_ISA_M32R1 &&
+ c->isa_level != MIPS_CPU_ISA_M32R2 &&
+ c->isa_level != MIPS_CPU_ISA_M64R1 &&
+ c->isa_level != MIPS_CPU_ISA_M64R2)
+ return 0;
+
+ /* Does this MIPS32/MIPS64 CPU have a config2 register? */
+ config1 = read_c0_config1();
+ if (!(config1 & MIPS_CONF_M))
+ return 0;
+
+ config2 = read_c0_config2();
+ tmp = (config2 >> 4) & 0x0f;
+ if (0 < tmp && tmp <= 7)
+ c->scache.linesz = 2 << tmp;
+ else
+ return 0;
+
+ tmp = (config2 >> 8) & 0x0f;
+ if (0 <= tmp && tmp <= 7)
+ c->scache.sets = 64 << tmp;
+ else
+ return 0;
+
+ tmp = (config2 >> 0) & 0x0f;
+ if (0 <= tmp && tmp <= 7)
+ c->scache.ways = tmp + 1;
+ else
+ return 0;
+
+ c->scache.waysize = c->scache.sets * c->scache.linesz;
+
+ c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
+
+ return 1;
+}
+
+int __init mips_sc_init(void)
+{
+ int found = mips_sc_probe ();
+ if (found) {
+ mips_sc_enable();
+ bcops = &mips_sc_ops;
+ }
+ return found;
+}
+