1 files changed, 67 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/cpu-imx31.c b/arch/arm/mach-imx/cpu-imx31.c
new file mode 100644
index 000000000..35c544924
--- /dev/null
+++ b/arch/arm/mach-imx/cpu-imx31.c
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * MX31 CPU type detection
+ *
+ * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
+ */
+
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+
+#include "common.h"
+#include "hardware.h"
+#include "iim.h"
+
+static int mx31_cpu_rev = -1;
+
+static struct {
+	u8 srev;
+	const char *name;
+	unsigned int rev;
+} mx31_cpu_type[] = {
+	{ .srev = 0x00, .name = "i.MX31(L)", .rev = IMX_CHIP_REVISION_1_0 },
+	{ .srev = 0x10, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_1_1 },
+	{ .srev = 0x11, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_1_1 },
+	{ .srev = 0x12, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_1_1 },
+	{ .srev = 0x13, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_1_1 },
+	{ .srev = 0x14, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_1_2 },
+	{ .srev = 0x15, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_1_2 },
+	{ .srev = 0x28, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_2_0 },
+	{ .srev = 0x29, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_2_0 },
+};
+
+static int mx31_read_cpu_rev(void)
+{
+	void __iomem *iim_base;
+	struct device_node *np;
+	u32 i, srev;
+
+	np = of_find_compatible_node(NULL, NULL, "fsl,imx31-iim");
+	iim_base = of_iomap(np, 0);
+	of_node_put(np);
+	BUG_ON(!iim_base);
+
+	/* read SREV register from IIM module */
+	srev = imx_readl(iim_base + MXC_IIMSREV);
+	srev &= 0xff;
+
+	for (i = 0; i < ARRAY_SIZE(mx31_cpu_type); i++)
+		if (srev == mx31_cpu_type[i].srev) {
+			imx_print_silicon_rev(mx31_cpu_type[i].name,
+						mx31_cpu_type[i].rev);
+			return mx31_cpu_type[i].rev;
+		}
+
+	imx_print_silicon_rev("i.MX31", IMX_CHIP_REVISION_UNKNOWN);
+	return IMX_CHIP_REVISION_UNKNOWN;
+}
+
+int mx31_revision(void)
+{
+	if (mx31_cpu_rev == -1)
+		mx31_cpu_rev = mx31_read_cpu_rev();
+
+	return mx31_cpu_rev;
+}
+EXPORT_SYMBOL(mx31_revision);