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authorColin Cross <ccross@android.com>2010-06-23 15:49:17 -0700
committerColin Cross <ccross@android.com>2010-10-21 18:12:09 -0700
commit73625e3e2e2bc36198f5b43e0f32d9dfb8e3b77c (patch)
tree14cadc153b0d27de39b06d5afe6ff7fac7fab853 /arch
parent2e47b8b3c2dc0f9f0651ee0f20e163da09b20fb9 (diff)
downloadop-kernel-dev-73625e3e2e2bc36198f5b43e0f32d9dfb8e3b77c.zip
op-kernel-dev-73625e3e2e2bc36198f5b43e0f32d9dfb8e3b77c.tar.gz
[ARM] tegra: Add support for reading fuses
The Tegra SOC contains fuses to identify the CPU type and bin, and a unique id. The CPU info is required to determine the correct voltages for each cpu and core frequency. Signed-off-by: Colin Cross <ccross@android.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/mach-tegra/Makefile1
-rw-r--r--arch/arm/mach-tegra/common.c2
-rw-r--r--arch/arm/mach-tegra/fuse.c84
-rw-r--r--arch/arm/mach-tegra/fuse.h24
4 files changed, 111 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile
index 87d065e..6203475 100644
--- a/arch/arm/mach-tegra/Makefile
+++ b/arch/arm/mach-tegra/Makefile
@@ -5,6 +5,7 @@ obj-y += clock.o
obj-y += timer.o
obj-y += gpio.o
obj-y += pinmux.o
+obj-y += fuse.o
obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += clock.o
obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra2_clocks.o
obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += pinmux-t2-tables.o
diff --git a/arch/arm/mach-tegra/common.c b/arch/arm/mach-tegra/common.c
index 039a514..9aedaf7 100644
--- a/arch/arm/mach-tegra/common.c
+++ b/arch/arm/mach-tegra/common.c
@@ -26,6 +26,7 @@
#include "board.h"
#include "clock.h"
+#include "fuse.h"
static __initdata struct tegra_clk_init_table common_clk_init_table[] = {
/* name parent rate enabled */
@@ -55,6 +56,7 @@ void __init tegra_init_cache(void)
void __init tegra_common_init(void)
{
+ tegra_init_fuse();
tegra_init_clock();
tegra_clk_init_from_table(common_clk_init_table);
tegra_init_cache();
diff --git a/arch/arm/mach-tegra/fuse.c b/arch/arm/mach-tegra/fuse.c
new file mode 100644
index 0000000..1fa26d9
--- /dev/null
+++ b/arch/arm/mach-tegra/fuse.c
@@ -0,0 +1,84 @@
+/*
+ * arch/arm/mach-tegra/fuse.c
+ *
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * Author:
+ * Colin Cross <ccross@android.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+
+#include <mach/iomap.h>
+
+#include "fuse.h"
+
+#define FUSE_UID_LOW 0x108
+#define FUSE_UID_HIGH 0x10c
+#define FUSE_SKU_INFO 0x110
+#define FUSE_SPARE_BIT 0x200
+
+static inline u32 fuse_readl(unsigned long offset)
+{
+ return readl(IO_TO_VIRT(TEGRA_FUSE_BASE + offset));
+}
+
+static inline void fuse_writel(u32 value, unsigned long offset)
+{
+ writel(value, IO_TO_VIRT(TEGRA_FUSE_BASE + offset));
+}
+
+void tegra_init_fuse(void)
+{
+ u32 reg = readl(IO_TO_VIRT(TEGRA_CLK_RESET_BASE + 0x48));
+ reg |= 1 << 28;
+ writel(reg, IO_TO_VIRT(TEGRA_CLK_RESET_BASE + 0x48));
+
+ pr_info("Tegra SKU: %d CPU Process: %d Core Process: %d\n",
+ tegra_sku_id(), tegra_cpu_process_id(),
+ tegra_core_process_id());
+}
+
+unsigned long long tegra_chip_uid(void)
+{
+ unsigned long long lo, hi;
+
+ lo = fuse_readl(FUSE_UID_LOW);
+ hi = fuse_readl(FUSE_UID_HIGH);
+ return (hi << 32ull) | lo;
+}
+
+int tegra_sku_id(void)
+{
+ int sku_id;
+ u32 reg = fuse_readl(FUSE_SKU_INFO);
+ sku_id = reg & 0xFF;
+ return sku_id;
+}
+
+int tegra_cpu_process_id(void)
+{
+ int cpu_process_id;
+ u32 reg = fuse_readl(FUSE_SPARE_BIT);
+ cpu_process_id = (reg >> 6) & 3;
+ return cpu_process_id;
+}
+
+int tegra_core_process_id(void)
+{
+ int core_process_id;
+ u32 reg = fuse_readl(FUSE_SPARE_BIT);
+ core_process_id = (reg >> 12) & 3;
+ return core_process_id;
+}
diff --git a/arch/arm/mach-tegra/fuse.h b/arch/arm/mach-tegra/fuse.h
new file mode 100644
index 0000000..584b2e2
--- /dev/null
+++ b/arch/arm/mach-tegra/fuse.h
@@ -0,0 +1,24 @@
+/*
+ * arch/arm/mach-tegra/fuse.c
+ *
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * Author:
+ * Colin Cross <ccross@android.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+unsigned long long tegra_chip_uid(void);
+int tegra_sku_id(void);
+int tegra_cpu_process_id(void);
+int tegra_core_process_id(void);
+void tegra_init_fuse(void);
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