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-rw-r--r--arch/m68k/mm/memory.c192
1 files changed, 192 insertions, 0 deletions
diff --git a/arch/m68k/mm/memory.c b/arch/m68k/mm/memory.c
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+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/arch/m68k/mm/memory.c
+ *
+ * Copyright (C) 1995 Hamish Macdonald
+ */
+
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/pagemap.h>
+#include <linux/gfp.h>
+
+#include <asm/setup.h>
+#include <asm/page.h>
+#include <asm/traps.h>
+#include <asm/machdep.h>
+
+
+/* invalidate page in both caches */
+static inline void clear040(unsigned long paddr)
+{
+ asm volatile (
+ "nop\n\t"
+ ".chip 68040\n\t"
+ "cinvp %%bc,(%0)\n\t"
+ ".chip 68k"
+ : : "a" (paddr));
+}
+
+/* invalidate page in i-cache */
+static inline void cleari040(unsigned long paddr)
+{
+ asm volatile (
+ "nop\n\t"
+ ".chip 68040\n\t"
+ "cinvp %%ic,(%0)\n\t"
+ ".chip 68k"
+ : : "a" (paddr));
+}
+
+/* push page in both caches */
+/* RZ: cpush %bc DOES invalidate %ic, regardless of DPI */
+static inline void push040(unsigned long paddr)
+{
+ asm volatile (
+ "nop\n\t"
+ ".chip 68040\n\t"
+ "cpushp %%bc,(%0)\n\t"
+ ".chip 68k"
+ : : "a" (paddr));
+}
+
+/* push and invalidate page in both caches, must disable ints
+ * to avoid invalidating valid data */
+static inline void pushcl040(unsigned long paddr)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ push040(paddr);
+ if (CPU_IS_060)
+ clear040(paddr);
+ local_irq_restore(flags);
+}
+
+/*
+ * 040: Hit every page containing an address in the range paddr..paddr+len-1.
+ * (Low order bits of the ea of a CINVP/CPUSHP are "don't care"s).
+ * Hit every page until there is a page or less to go. Hit the next page,
+ * and the one after that if the range hits it.
+ */
+/* ++roman: A little bit more care is required here: The CINVP instruction
+ * invalidates cache entries WITHOUT WRITING DIRTY DATA BACK! So the beginning
+ * and the end of the region must be treated differently if they are not
+ * exactly at the beginning or end of a page boundary. Else, maybe too much
+ * data becomes invalidated and thus lost forever. CPUSHP does what we need:
+ * it invalidates the page after pushing dirty data to memory. (Thanks to Jes
+ * for discovering the problem!)
+ */
+/* ... but on the '060, CPUSH doesn't invalidate (for us, since we have set
+ * the DPI bit in the CACR; would it cause problems with temporarily changing
+ * this?). So we have to push first and then additionally to invalidate.
+ */
+
+
+/*
+ * cache_clear() semantics: Clear any cache entries for the area in question,
+ * without writing back dirty entries first. This is useful if the data will
+ * be overwritten anyway, e.g. by DMA to memory. The range is defined by a
+ * _physical_ address.
+ */
+
+void cache_clear (unsigned long paddr, int len)
+{
+ if (CPU_IS_COLDFIRE) {
+ clear_cf_bcache(0, DCACHE_MAX_ADDR);
+ } else if (CPU_IS_040_OR_060) {
+ int tmp;
+
+ /*
+ * We need special treatment for the first page, in case it
+ * is not page-aligned. Page align the addresses to work
+ * around bug I17 in the 68060.
+ */
+ if ((tmp = -paddr & (PAGE_SIZE - 1))) {
+ pushcl040(paddr & PAGE_MASK);
+ if ((len -= tmp) <= 0)
+ return;
+ paddr += tmp;
+ }
+ tmp = PAGE_SIZE;
+ paddr &= PAGE_MASK;
+ while ((len -= tmp) >= 0) {
+ clear040(paddr);
+ paddr += tmp;
+ }
+ if ((len += tmp))
+ /* a page boundary gets crossed at the end */
+ pushcl040(paddr);
+ }
+ else /* 68030 or 68020 */
+ asm volatile ("movec %/cacr,%/d0\n\t"
+ "oriw %0,%/d0\n\t"
+ "movec %/d0,%/cacr"
+ : : "i" (FLUSH_I_AND_D)
+ : "d0");
+#ifdef CONFIG_M68K_L2_CACHE
+ if(mach_l2_flush)
+ mach_l2_flush(0);
+#endif
+}
+EXPORT_SYMBOL(cache_clear);
+
+
+/*
+ * cache_push() semantics: Write back any dirty cache data in the given area,
+ * and invalidate the range in the instruction cache. It needs not (but may)
+ * invalidate those entries also in the data cache. The range is defined by a
+ * _physical_ address.
+ */
+
+void cache_push (unsigned long paddr, int len)
+{
+ if (CPU_IS_COLDFIRE) {
+ flush_cf_bcache(0, DCACHE_MAX_ADDR);
+ } else if (CPU_IS_040_OR_060) {
+ int tmp = PAGE_SIZE;
+
+ /*
+ * on 68040 or 68060, push cache lines for pages in the range;
+ * on the '040 this also invalidates the pushed lines, but not on
+ * the '060!
+ */
+ len += paddr & (PAGE_SIZE - 1);
+
+ /*
+ * Work around bug I17 in the 68060 affecting some instruction
+ * lines not being invalidated properly.
+ */
+ paddr &= PAGE_MASK;
+
+ do {
+ push040(paddr);
+ paddr += tmp;
+ } while ((len -= tmp) > 0);
+ }
+ /*
+ * 68030/68020 have no writeback cache. On the other hand,
+ * cache_push is actually a superset of cache_clear (the lines
+ * get written back and invalidated), so we should make sure
+ * to perform the corresponding actions. After all, this is getting
+ * called in places where we've just loaded code, or whatever, so
+ * flushing the icache is appropriate; flushing the dcache shouldn't
+ * be required.
+ */
+ else /* 68030 or 68020 */
+ asm volatile ("movec %/cacr,%/d0\n\t"
+ "oriw %0,%/d0\n\t"
+ "movec %/d0,%/cacr"
+ : : "i" (FLUSH_I)
+ : "d0");
+#ifdef CONFIG_M68K_L2_CACHE
+ if(mach_l2_flush)
+ mach_l2_flush(1);
+#endif
+}
+EXPORT_SYMBOL(cache_push);
+