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Diffstat (limited to 'kernel/arch/arm/mach-imx/cpu-imx5.c')
-rw-r--r--kernel/arch/arm/mach-imx/cpu-imx5.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-imx/cpu-imx5.c b/kernel/arch/arm/mach-imx/cpu-imx5.c
new file mode 100644
index 000000000..3403bac94
--- /dev/null
+++ b/kernel/arch/arm/mach-imx/cpu-imx5.c
@@ -0,0 +1,127 @@
+/*
+ * 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 <linux/of.h>
+#include <linux/of_address.h>
+
+#include "hardware.h"
+#include "common.h"
+
+static int mx5_cpu_rev = -1;
+
+#define IIM_SREV 0x24
+
+static u32 imx5_read_srev_reg(const char *compat)
+{
+ void __iomem *iim_base;
+ struct device_node *np;
+ u32 srev;
+
+ np = of_find_compatible_node(NULL, NULL, compat);
+ iim_base = of_iomap(np, 0);
+ WARN_ON(!iim_base);
+
+ srev = readl(iim_base + IIM_SREV) & 0xff;
+
+ iounmap(iim_base);
+
+ return srev;
+}
+
+static int get_mx51_srev(void)
+{
+ u32 rev = imx5_read_srev_reg("fsl,imx51-iim");
+
+ 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)
+{
+ u32 rev = imx5_read_srev_reg("fsl,imx53-iim");
+
+ 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);