tegra: Add PMU to manage power supplies

Power supplies must be adjusted in line with clock frequency. This code
provides a simple routine to set the voltage to allow operation at maximum
frequency.

- Split PMU code into separate TPS6586X driver

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>

diff --git a/arch/arm/cpu/armv7/tegra2/Makefile b/arch/arm/cpu/armv7/tegra2/Makefile
index dcd6329..dba684d 100644 (file)
--- a/arch/arm/cpu/armv7/tegra2/Makefile
+++ b/arch/arm/cpu/armv7/tegra2/Makefile
@@ -35,6 +35,7 @@ LIB   =  $(obj)lib$(SOC).o
 SOBJS  := lowlevel_init.o
 COBJS-y        := ap20.o board.o clock.o funcmux.o pinmux.o sys_info.o timer.o
 COBJS-$(CONFIG_TEGRA_CLOCK_SCALING) += emc.o
+COBJS-$(CONFIG_TEGRA_PMU) += pmu.o
 COBJS-$(CONFIG_USB_EHCI_TEGRA) += usb.o
 
 COBJS  := $(COBJS-y)

diff --git a/arch/arm/cpu/armv7/tegra2/pmu.c b/arch/arm/cpu/armv7/tegra2/pmu.c
new file mode 100644 (file)
index 0000000..4673802
--- /dev/null
+++ b/arch/arm/cpu/armv7/tegra2/pmu.c
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * (C) Copyright 2010,2011 NVIDIA Corporation <www.nvidia.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <tps6586x.h>
+#include <asm/io.h>
+#include <asm/arch/ap20.h>
+#include <asm/arch/tegra2.h>
+#include <asm/arch/tegra_i2c.h>
+#include <asm/arch/sys_proto.h>
+
+#define VDD_CORE_NOMINAL_T25   0x17    /* 1.3v */
+#define VDD_CPU_NOMINAL_T25    0x10    /* 1.125v */
+
+#define VDD_CORE_NOMINAL_T20   0x16    /* 1.275v */
+#define VDD_CPU_NOMINAL_T20    0x0f    /* 1.1v */
+
+#define VDD_RELATION           0x02    /*  50mv */
+#define VDD_TRANSITION_STEP    0x06    /* 150mv */
+#define VDD_TRANSITION_RATE    0x06    /* 3.52mv/us */
+
+int pmu_set_nominal(void)
+{
+       int core, cpu, bus;
+
+       /* by default, the table has been filled with T25 settings */
+       switch (tegra_get_chip_type()) {
+       case TEGRA_SOC_T20:
+               core = VDD_CORE_NOMINAL_T20;
+               cpu = VDD_CPU_NOMINAL_T20;
+               break;
+       case TEGRA_SOC_T25:
+               core = VDD_CORE_NOMINAL_T25;
+               cpu = VDD_CPU_NOMINAL_T25;
+               break;
+       default:
+               debug("%s: Unknown chip type\n", __func__);
+               return -1;
+       }
+
+       bus = tegra_i2c_get_dvc_bus_num();
+       if (bus == -1) {
+               debug("%s: Cannot find DVC I2C bus\n", __func__);
+               return -1;
+       }
+       tps6586x_init(bus);
+       tps6586x_set_pwm_mode(TPS6586X_PWM_SM1);
+       return tps6586x_adjust_sm0_sm1(core, cpu, VDD_TRANSITION_STEP,
+                               VDD_TRANSITION_RATE, VDD_RELATION);
+}

diff --git a/arch/arm/include/asm/arch-tegra2/pmu.h b/arch/arm/include/asm/arch-tegra2/pmu.h
new file mode 100644 (file)
index 0000000..390815f
--- /dev/null
+++ b/arch/arm/include/asm/arch-tegra2/pmu.h
@@ -0,0 +1,30 @@
+/*
+ *  (C) Copyright 2010,2011
+ *  NVIDIA Corporation <www.nvidia.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _ARCH_PMU_H_
+#define _ARCH_PMU_H_
+
+/* Set core and CPU voltages to nominal levels */
+int pmu_set_nominal(void);
+
+#endif /* _ARCH_PMU_H_ */