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-rw-r--r--arch/mips/dec/wbflush.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/arch/mips/dec/wbflush.c b/arch/mips/dec/wbflush.c
new file mode 100644
index 00000000000..925c0525344
--- /dev/null
+++ b/arch/mips/dec/wbflush.c
@@ -0,0 +1,94 @@
+/*
+ * Setup the right wbflush routine for the different DECstations.
+ *
+ * Created with information from:
+ * DECstation 3100 Desktop Workstation Functional Specification
+ * DECstation 5000/200 KN02 System Module Functional Specification
+ * mipsel-linux-objdump --disassemble vmunix | grep "wbflush" :-)
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1998 Harald Koerfgen
+ * Copyright (C) 2002 Maciej W. Rozycki
+ */
+
+#include <linux/init.h>
+
+#include <asm/bootinfo.h>
+#include <asm/system.h>
+#include <asm/wbflush.h>
+
+static void wbflush_kn01(void);
+static void wbflush_kn210(void);
+static void wbflush_mips(void);
+
+void (*__wbflush) (void);
+
+void __init wbflush_setup(void)
+{
+ switch (mips_machtype) {
+ case MACH_DS23100:
+ case MACH_DS5000_200: /* DS5000 3max */
+ __wbflush = wbflush_kn01;
+ break;
+ case MACH_DS5100: /* DS5100 MIPSMATE */
+ __wbflush = wbflush_kn210;
+ break;
+ case MACH_DS5000_1XX: /* DS5000/100 3min */
+ case MACH_DS5000_XX: /* Personal DS5000/2x */
+ case MACH_DS5000_2X0: /* DS5000/240 3max+ */
+ case MACH_DS5900: /* DS5900 bigmax */
+ default:
+ __wbflush = wbflush_mips;
+ break;
+ }
+}
+
+/*
+ * For the DS3100 and DS5000/200 the R2020/R3220 writeback buffer functions
+ * as part of Coprocessor 0.
+ */
+static void wbflush_kn01(void)
+{
+ asm(".set\tpush\n\t"
+ ".set\tnoreorder\n\t"
+ "1:\tbc0f\t1b\n\t"
+ "nop\n\t"
+ ".set\tpop");
+}
+
+/*
+ * For the DS5100 the writeback buffer seems to be a part of Coprocessor 3.
+ * But CP3 has to enabled first.
+ */
+static void wbflush_kn210(void)
+{
+ asm(".set\tpush\n\t"
+ ".set\tnoreorder\n\t"
+ "mfc0\t$2,$12\n\t"
+ "lui\t$3,0x8000\n\t"
+ "or\t$3,$2,$3\n\t"
+ "mtc0\t$3,$12\n\t"
+ "nop\n"
+ "1:\tbc3f\t1b\n\t"
+ "nop\n\t"
+ "mtc0\t$2,$12\n\t"
+ "nop\n\t"
+ ".set\tpop"
+ : : : "$2", "$3");
+}
+
+/*
+ * I/O ASIC systems use a standard writeback buffer that gets flushed
+ * upon an uncached read.
+ */
+static void wbflush_mips(void)
+{
+ __fast_iob();
+}
+
+#include <linux/module.h>
+
+EXPORT_SYMBOL(__wbflush);