[PATCH 1/2] ARM: tegra: Add speedo-based process identification
Danny Huang
dahuang at nvidia.com
Mon Oct 29 03:21:54 EDT 2012
Detect CPU and core process ID by checking speedo corner tables.
This can provide a more accurate process ID.
Signed-off-by: Danny Huang <dahuang at nvidia.com>
---
arch/arm/mach-tegra/Makefile | 1 +
arch/arm/mach-tegra/fuse.c | 13 ++---
arch/arm/mach-tegra/fuse.h | 8 +++
arch/arm/mach-tegra/tegra20_speedo.c | 102 +++++++++++++++++++++++++++++++++++
4 files changed, 116 insertions(+), 8 deletions(-)
create mode 100644 arch/arm/mach-tegra/tegra20_speedo.c
diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile
index 9aa653b..7ab6092 100644
--- a/arch/arm/mach-tegra/Makefile
+++ b/arch/arm/mach-tegra/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_CPU_IDLE) += sleep.o
obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra20_clocks.o
obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra20_clocks_data.o
obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra2_emc.o
+obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra20_speedo.o
obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += sleep-t20.o
obj-$(CONFIG_ARCH_TEGRA_3x_SOC) += tegra30_clocks.o
obj-$(CONFIG_ARCH_TEGRA_3x_SOC) += tegra30_clocks_data.o
diff --git a/arch/arm/mach-tegra/fuse.c b/arch/arm/mach-tegra/fuse.c
index 0b7db17..b28e6d2 100644
--- a/arch/arm/mach-tegra/fuse.c
+++ b/arch/arm/mach-tegra/fuse.c
@@ -35,6 +35,7 @@ int tegra_sku_id;
int tegra_cpu_process_id;
int tegra_core_process_id;
int tegra_chip_id;
+int tegra_soc_speedo_id;
enum tegra_revision tegra_revision;
/* The BCT to use at boot is specified by board straps that can be read
@@ -62,7 +63,7 @@ static inline u32 tegra_fuse_readl(unsigned long offset)
return tegra_apb_readl(TEGRA_FUSE_BASE + offset);
}
-static inline bool get_spare_fuse(int bit)
+unsigned int tegra_spare_fuse(int bit)
{
return tegra_fuse_readl(FUSE_SPARE_BIT + bit * 4);
}
@@ -78,7 +79,7 @@ static enum tegra_revision tegra_get_revision(u32 id)
return TEGRA_REVISION_A02;
case 3:
if (tegra_chip_id == TEGRA20 &&
- (get_spare_fuse(18) || get_spare_fuse(19)))
+ (tegra_spare_fuse(18) || tegra_spare_fuse(19)))
return TEGRA_REVISION_A03p;
else
return TEGRA_REVISION_A03;
@@ -100,12 +101,6 @@ void tegra_init_fuse(void)
reg = tegra_fuse_readl(FUSE_SKU_INFO);
tegra_sku_id = reg & 0xFF;
- reg = tegra_fuse_readl(FUSE_SPARE_BIT);
- tegra_cpu_process_id = (reg >> 6) & 3;
-
- reg = tegra_fuse_readl(FUSE_SPARE_BIT);
- tegra_core_process_id = (reg >> 12) & 3;
-
reg = tegra_apb_readl(TEGRA_APB_MISC_BASE + STRAP_OPT);
tegra_bct_strapping = (reg & RAM_ID_MASK) >> RAM_CODE_SHIFT;
@@ -114,6 +109,8 @@ void tegra_init_fuse(void)
tegra_revision = tegra_get_revision(id);
+ tegra20_init_speedo_data();
+
pr_info("Tegra Revision: %s SKU: %d CPU Process: %d Core Process: %d\n",
tegra_revision_name[tegra_revision],
tegra_sku_id, tegra_cpu_process_id,
diff --git a/arch/arm/mach-tegra/fuse.h b/arch/arm/mach-tegra/fuse.h
index d2107b2..f1cafb9 100644
--- a/arch/arm/mach-tegra/fuse.h
+++ b/arch/arm/mach-tegra/fuse.h
@@ -42,11 +42,19 @@ extern int tegra_sku_id;
extern int tegra_cpu_process_id;
extern int tegra_core_process_id;
extern int tegra_chip_id;
+extern int tegra_soc_speedo_id;
extern enum tegra_revision tegra_revision;
extern int tegra_bct_strapping;
unsigned long long tegra_chip_uid(void);
void tegra_init_fuse(void);
+unsigned int tegra_spare_fuse(int bit);
+
+#ifdef CONFIG_ARCH_TEGRA_2x_SOC
+void tegra20_init_speedo_data(void);
+#else
+static inline void tegra20_init_speedo_data(void) {}
+#endif
#endif
diff --git a/arch/arm/mach-tegra/tegra20_speedo.c b/arch/arm/mach-tegra/tegra20_speedo.c
new file mode 100644
index 0000000..b9202ea
--- /dev/null
+++ b/arch/arm/mach-tegra/tegra20_speedo.c
@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/kernel.h>
+#include <linux/bug.h>
+
+#include "fuse.h"
+
+#define CPU_SPEEDO_LSBIT 20
+#define CPU_SPEEDO_MSBIT 29
+#define CPU_SPEEDO_REDUND_LSBIT 30
+#define CPU_SPEEDO_REDUND_MSBIT 39
+#define CPU_SPEEDO_REDUND_OFFS (CPU_SPEEDO_REDUND_MSBIT - CPU_SPEEDO_MSBIT)
+
+#define CORE_SPEEDO_LSBIT 40
+#define CORE_SPEEDO_MSBIT 47
+#define CORE_SPEEDO_REDUND_LSBIT 48
+#define CORE_SPEEDO_REDUND_MSBIT 55
+#define CORE_SPEEDO_REDUND_OFFS (CORE_SPEEDO_REDUND_MSBIT - CORE_SPEEDO_MSBIT)
+
+#define SPEEDO_MULT 4
+
+#define PROCESS_CORNERS_NUM 4
+
+#define SPEEDO_ID_SELECT_0(rev) ((rev) <= 2)
+#define SPEEDO_ID_SELECT_1(sku) \
+ (((sku) != 20) && ((sku) != 23) && ((sku) != 24) && \
+ ((sku) != 27) && ((sku) != 28))
+
+static const u32 cpu_process_speedos[][PROCESS_CORNERS_NUM] = {
+ {315, 366, 420, UINT_MAX},
+ {303, 368, 419, UINT_MAX},
+ {316, 331, 383, UINT_MAX},
+};
+
+static const u32 core_process_speedos[][PROCESS_CORNERS_NUM] = {
+ {165, 195, 224, UINT_MAX},
+ {165, 195, 224, UINT_MAX},
+ {165, 195, 224, UINT_MAX},
+};
+
+void tegra20_init_speedo_data(void)
+{
+ u32 reg;
+ u32 val;
+ int i;
+
+ if (SPEEDO_ID_SELECT_0(tegra_revision))
+ tegra_soc_speedo_id = 0;
+ else if (SPEEDO_ID_SELECT_1(tegra_sku_id))
+ tegra_soc_speedo_id = 1;
+ else
+ tegra_soc_speedo_id = 2;
+
+ WARN_ON(tegra_soc_speedo_id >= ARRAY_SIZE(cpu_process_speedos));
+ WARN_ON(tegra_soc_speedo_id >= ARRAY_SIZE(core_process_speedos));
+
+ val = 0;
+ for (i = CPU_SPEEDO_MSBIT; i >= CPU_SPEEDO_LSBIT; i--) {
+ reg = tegra_spare_fuse(i) |
+ tegra_spare_fuse(i + CPU_SPEEDO_REDUND_OFFS);
+ val = (val << 1) | (reg & 0x1);
+ }
+ val = val * SPEEDO_MULT;
+ pr_debug("%s CPU speedo value %u\n", __func__, val);
+
+ for (i = 0; i < (PROCESS_CORNERS_NUM - 1); i++) {
+ if (val <= cpu_process_speedos[tegra_soc_speedo_id][i])
+ break;
+ }
+ tegra_cpu_process_id = i;
+
+ val = 0;
+ for (i = CORE_SPEEDO_MSBIT; i >= CORE_SPEEDO_LSBIT; i--) {
+ reg = tegra_spare_fuse(i) |
+ tegra_spare_fuse(i + CORE_SPEEDO_REDUND_OFFS);
+ val = (val << 1) | (reg & 0x1);
+ }
+ val = val * SPEEDO_MULT;
+ pr_debug("%s Core speedo value %u\n", __func__, val);
+
+ for (i = 0; i < (PROCESS_CORNERS_NUM - 1); i++) {
+ if (val <= core_process_speedos[tegra_soc_speedo_id][i])
+ break;
+ }
+ tegra_core_process_id = i;
+
+ pr_info("Tegra2 Soc Speedo ID %d", tegra_soc_speedo_id);
+}
--
1.8.0
More information about the linux-arm-kernel
mailing list