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authorPaul Mundt <lethal@linux-sh.org>2007-11-20 18:27:20 +0900
committerPaul Mundt <lethal@linux-sh.org>2008-01-28 13:18:50 +0900
commitd1839136098e281ece46520200599ef94edca612 (patch)
tree77352e7de98dccea141287e418c5868165152e83 /arch/sh/kernel
parent92b59258b8e854dd223bbb196f0c18b8cb7e6c6e (diff)
sh: Plug in simple SH-5 subtype probing.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/kernel')
-rw-r--r--arch/sh/kernel/cpu/sh5/Makefile4
-rw-r--r--arch/sh/kernel/cpu/sh5/probe.c76
2 files changed, 78 insertions, 2 deletions
diff --git a/arch/sh/kernel/cpu/sh5/Makefile b/arch/sh/kernel/cpu/sh5/Makefile
index 6d388e8d8991..c7a9873c8d57 100644
--- a/arch/sh/kernel/cpu/sh5/Makefile
+++ b/arch/sh/kernel/cpu/sh5/Makefile
@@ -1,4 +1,4 @@
-obj-y := entry.o switchto.o
+obj-y := entry.o probe.o switchto.o
-obj-$(CONFIG_KALLSYMS) += unwind.o
obj-$(CONFIG_SH_FPU) += fpu.o
+obj-$(CONFIG_KALLSYMS) += unwind.o
diff --git a/arch/sh/kernel/cpu/sh5/probe.c b/arch/sh/kernel/cpu/sh5/probe.c
new file mode 100644
index 000000000000..15d167fd0ae7
--- /dev/null
+++ b/arch/sh/kernel/cpu/sh5/probe.c
@@ -0,0 +1,76 @@
+/*
+ * arch/sh/kernel/cpu/sh5/probe.c
+ *
+ * CPU Subtype Probing for SH-5.
+ *
+ * Copyright (C) 2000, 2001 Paolo Alberelli
+ * Copyright (C) 2003 - 2007 Paul Mundt
+ *
+ * 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.
+ */
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/string.h>
+#include <asm/processor.h>
+#include <asm/cache.h>
+
+int __init detect_cpu_and_cache_system(void)
+{
+ unsigned long long cir;
+
+ /* Do peeks in real mode to avoid having to set up a mapping for the
+ WPC registers. On SH5-101 cut2, such a mapping would be exposed to
+ an address translation erratum which would make it hard to set up
+ correctly. */
+ cir = peek_real_address_q(0x0d000008);
+ if ((cir & 0xffff) == 0x5103) {
+ boot_cpu_data.type = CPU_SH5_103;
+ } else if (((cir >> 32) & 0xffff) == 0x51e2) {
+ /* CPU.VCR aliased at CIR address on SH5-101 */
+ boot_cpu_data.type = CPU_SH5_101;
+ } else {
+ boot_cpu_data.type = CPU_SH_NONE;
+ }
+
+ /*
+ * First, setup some sane values for the I-cache.
+ */
+ boot_cpu_data.icache.ways = 4;
+ boot_cpu_data.icache.sets = 256;
+ boot_cpu_data.icache.linesz = L1_CACHE_BYTES;
+
+#if 0
+ /*
+ * FIXME: This can probably be cleaned up a bit as well.. for example,
+ * do we really need the way shift _and_ the way_step_shift ?? Judging
+ * by the existing code, I would guess no.. is there any valid reason
+ * why we need to be tracking this around?
+ */
+ boot_cpu_data.icache.way_shift = 13;
+ boot_cpu_data.icache.entry_shift = 5;
+ boot_cpu_data.icache.set_shift = 4;
+ boot_cpu_data.icache.way_step_shift = 16;
+ boot_cpu_data.icache.asid_shift = 2;
+
+ /*
+ * way offset = cache size / associativity, so just don't factor in
+ * associativity in the first place..
+ */
+ boot_cpu_data.icache.way_ofs = boot_cpu_data.icache.sets *
+ boot_cpu_data.icache.linesz;
+
+ boot_cpu_data.icache.asid_mask = 0x3fc;
+ boot_cpu_data.icache.idx_mask = 0x1fe0;
+ boot_cpu_data.icache.epn_mask = 0xffffe000;
+#endif
+
+ boot_cpu_data.icache.flags = 0;
+
+ /* A trivial starting point.. */
+ memcpy(&boot_cpu_data.dcache,
+ &boot_cpu_data.icache, sizeof(struct cache_info));
+
+ return 0;
+}