Initial commit

arch/arm/mach-imx/cpu-imx5.c

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2008-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * This file contains the CPU initialization code.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/io.h>
+
+#include "hardware.h"
+#include "common.h"
+
+static int mx5_cpu_rev = -1;
+
+#define IIM_SREV 0x24
+
+static int get_mx51_srev(void)
+{
+	void __iomem *iim_base = MX51_IO_ADDRESS(MX51_IIM_BASE_ADDR);
+	u32 rev = readl(iim_base + IIM_SREV) & 0xff;
+
+	switch (rev) {
+	case 0x0:
+		return IMX_CHIP_REVISION_2_0;
+	case 0x10:
+		return IMX_CHIP_REVISION_3_0;
+	default:
+		return IMX_CHIP_REVISION_UNKNOWN;
+	}
+}
+
+/*
+ * Returns:
+ *	the silicon revision of the cpu
+ *	-EINVAL - not a mx51
+ */
+int mx51_revision(void)
+{
+	if (!cpu_is_mx51())
+		return -EINVAL;
+
+	if (mx5_cpu_rev == -1)
+		mx5_cpu_rev = get_mx51_srev();
+
+	return mx5_cpu_rev;
+}
+EXPORT_SYMBOL(mx51_revision);
+
+#ifdef CONFIG_NEON
+
+/*
+ * All versions of the silicon before Rev. 3 have broken NEON implementations.
+ * Dependent on link order - so the assumption is that vfp_init is called
+ * before us.
+ */
+int __init mx51_neon_fixup(void)
+{
+	if (mx51_revision() < IMX_CHIP_REVISION_3_0 &&
+			(elf_hwcap & HWCAP_NEON)) {
+		elf_hwcap &= ~HWCAP_NEON;
+		pr_info("Turning off NEON support, detected broken NEON implementation\n");
+	}
+	return 0;
+}
+
+#endif
+
+static int get_mx53_srev(void)
+{
+	void __iomem *iim_base = MX51_IO_ADDRESS(MX53_IIM_BASE_ADDR);
+	u32 rev = readl(iim_base + IIM_SREV) & 0xff;
+
+	switch (rev) {
+	case 0x0:
+		return IMX_CHIP_REVISION_1_0;
+	case 0x2:
+		return IMX_CHIP_REVISION_2_0;
+	case 0x3:
+		return IMX_CHIP_REVISION_2_1;
+	default:
+		return IMX_CHIP_REVISION_UNKNOWN;
+	}
+}
+
+/*
+ * Returns:
+ *	the silicon revision of the cpu
+ *	-EINVAL - not a mx53
+ */
+int mx53_revision(void)
+{
+	if (!cpu_is_mx53())
+		return -EINVAL;
+
+	if (mx5_cpu_rev == -1)
+		mx5_cpu_rev = get_mx53_srev();
+
+	return mx5_cpu_rev;
+}
+EXPORT_SYMBOL(mx53_revision);