sh: Plug in simple SH-5 subtype probing.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 76 insertions, 0 deletions

diff --git a/arch/sh/kernel/cpu/sh5/probe.c b/arch/sh/kernel/cpu/sh5/probe.c
new file mode 100644
index 00000000000..15d167fd0ae
--- /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;
+}