[PATCH v3 1/9] ARM: tegra: Add function to read chipid

Prashant Gaikwad pgaikwad at nvidia.com
Fri Jan 4 04:40:45 EST 2013


Add function to read chip id from APB MISC registers. This function
will also get called from clock driver to flush write operations on
apb bus.

Signed-off-by: Prashant Gaikwad <pgaikwad at nvidia.com>
---
 arch/arm/mach-tegra/fuse.c |   12 ++++++++++--
 include/linux/tegra-soc.h  |   22 ++++++++++++++++++++++
 2 files changed, 32 insertions(+), 2 deletions(-)
 create mode 100644 include/linux/tegra-soc.h

diff --git a/arch/arm/mach-tegra/fuse.c b/arch/arm/mach-tegra/fuse.c
index 8121742..2cd8ac9 100644
--- a/arch/arm/mach-tegra/fuse.c
+++ b/arch/arm/mach-tegra/fuse.c
@@ -20,6 +20,7 @@
 #include <linux/kernel.h>
 #include <linux/io.h>
 #include <linux/export.h>
+#include <linux/tegra-soc.h>
 
 #include "fuse.h"
 #include "iomap.h"
@@ -105,6 +106,14 @@ static void tegra_get_process_id(void)
 	tegra_core_process_id = (reg >> 12) & 3;
 }
 
+void tegra_read_chipid(void)
+{
+	u32 reg;
+
+	reg = readl_relaxed(IO_ADDRESS(TEGRA_APB_MISC_BASE) + 0x804);
+	tegra_chip_id = (reg >> 8) & 0xff;
+}
+
 void tegra_init_fuse(void)
 {
 	u32 id;
@@ -119,8 +128,7 @@ void tegra_init_fuse(void)
 	reg = tegra_apb_readl(TEGRA_APB_MISC_BASE + STRAP_OPT);
 	tegra_bct_strapping = (reg & RAM_ID_MASK) >> RAM_CODE_SHIFT;
 
-	id = readl_relaxed(IO_ADDRESS(TEGRA_APB_MISC_BASE) + 0x804);
-	tegra_chip_id = (id >> 8) & 0xff;
+	tegra_read_chipid();
 
 	switch (tegra_chip_id) {
 	case TEGRA20:
diff --git a/include/linux/tegra-soc.h b/include/linux/tegra-soc.h
new file mode 100644
index 0000000..dcbc14c
--- /dev/null
+++ b/include/linux/tegra-soc.h
@@ -0,0 +1,22 @@
+/*
+ * 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/>.
+ */
+
+#ifndef __LINUX_TEGRA_SOC_H_
+#define __LINUX_TEGRA_SOC_H_
+
+void tegra_read_chipid(void);
+
+#endif /* __LINUX_TEGRA_SOC_H_ */
-- 
1.7.4.1




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