From 73625e3e2e2bc36198f5b43e0f32d9dfb8e3b77c Mon Sep 17 00:00:00 2001 From: Colin Cross Date: Wed, 23 Jun 2010 15:49:17 -0700 Subject: [PATCH] [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 --- arch/arm/mach-tegra/Makefile | 1 + arch/arm/mach-tegra/common.c | 2 ++ arch/arm/mach-tegra/fuse.c | 84 ++++++++++++++++++++++++++++++++++++++++++++ arch/arm/mach-tegra/fuse.h | 24 +++++++++++++ 4 files changed, 111 insertions(+) create mode 100644 arch/arm/mach-tegra/fuse.c create mode 100644 arch/arm/mach-tegra/fuse.h diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile index 87d065e65113..620347525272 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 039a514b61ef..9aedaf77013c 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 000000000000..1fa26d9a1a68 --- /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 + * + * 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 +#include + +#include + +#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 000000000000..584b2e27dbda --- /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 + * + * 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); -- 2.11.0