1 files changed, 94 insertions, 0 deletions
diff --git a/arch/arm/mach-davinci/id.c b/arch/arm/mach-davinci/id.c
new file mode 100644
index 00000000000..70608f76aed
--- /dev/null
+++ b/arch/arm/mach-davinci/id.c
@@ -0,0 +1,94 @@
+/*
+ * Davinci CPU identification code
+ *
+ * Copyright (C) 2006 Komal Shah <komal_shah802003@yahoo.com>
+ *
+ * Derived from OMAP1 CPU identification code.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+
+#include <asm/io.h>
+
+#define JTAG_ID_BASE		0x01c40028
+
+struct davinci_id {
+	u8	variant;	/* JTAG ID bits 31:28 */
+	u16	part_no;	/* JTAG ID bits 27:12 */
+	u32	manufacturer;	/* JTAG ID bits 11:1 */
+	u32	type;		/* Cpu id bits [31:8], cpu class bits [7:0] */
+};
+
+/* Register values to detect the DaVinci version */
+static struct davinci_id davinci_ids[] __initdata = {
+	{
+		/* DM6446 */
+		.part_no      = 0xb700,
+		.variant      = 0x0,
+		.manufacturer = 0x017,
+		.type	      = 0x64460000,
+	},
+};
+
+/*
+ * Get Device Part No. from JTAG ID register
+ */
+static u16 __init davinci_get_part_no(void)
+{
+	u32 dev_id, part_no;
+
+	dev_id = davinci_readl(JTAG_ID_BASE);
+
+	part_no = ((dev_id >> 12) & 0xffff);
+
+	return part_no;
+}
+
+/*
+ * Get Device Revision from JTAG ID register
+ */
+static u8 __init davinci_get_variant(void)
+{
+	u32 variant;
+
+	variant = davinci_readl(JTAG_ID_BASE);
+
+	variant = (variant >> 28) & 0xf;
+
+	return variant;
+}
+
+void __init davinci_check_revision(void)
+{
+	int i;
+	u16 part_no;
+	u8 variant;
+
+	part_no = davinci_get_part_no();
+	variant = davinci_get_variant();
+
+	/* First check only the major version in a safe way */
+	for (i = 0; i < ARRAY_SIZE(davinci_ids); i++) {
+		if (part_no == (davinci_ids[i].part_no)) {
+			system_rev = davinci_ids[i].type;
+			break;
+		}
+	}
+
+	/* Check if we can find the dev revision */
+	for (i = 0; i < ARRAY_SIZE(davinci_ids); i++) {
+		if (part_no == davinci_ids[i].part_no &&
+		    variant == davinci_ids[i].variant) {
+			system_rev = davinci_ids[i].type;
+			break;
+		}
+	}
+
+	printk("DaVinci DM%04x variant 0x%x\n", system_rev >> 16, variant);
+}