ARM: tegra: Implement powergate support

Implement the powergate API that allows various power partitions to be
power up and down.

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

arch/arm/cpu/tegra-common/Makefile

@@ -13,5 +13,6 @@ obj-y += cache.o
 obj-y += clock.o
 obj-y += lowlevel_init.o
 obj-y += pinmux-common.o
+obj-y += powergate.o
 obj-$(CONFIG_DISPLAY_CPUINFO) += sys_info.o
 obj-$(CONFIG_TEGRA124) += vpr.o

arch/arm/cpu/tegra-common/powergate.c

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2014, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#include <common.h>
+#include <errno.h>
+
+#include <asm/io.h>
+#include <asm/types.h>
+
+#include <asm/arch/powergate.h>
+#include <asm/arch/tegra.h>
+
+#define PWRGATE_TOGGLE 0x30
+#define  PWRGATE_TOGGLE_START (1 << 8)
+
+#define REMOVE_CLAMPING 0x34
+
+#define PWRGATE_STATUS 0x38
+
+static int tegra_powergate_set(enum tegra_powergate id, bool state)
+{
+	u32 value, mask = state ? (1 << id) : 0, old_mask;
+	unsigned long start, timeout = 25;
+
+	value = readl(NV_PA_PMC_BASE + PWRGATE_STATUS);
+	old_mask = value & (1 << id);
+
+	if (mask == old_mask)
+		return 0;
+
+	writel(PWRGATE_TOGGLE_START | id, NV_PA_PMC_BASE + PWRGATE_TOGGLE);
+
+	start = get_timer(0);
+
+	while (get_timer(start) < timeout) {
+		value = readl(NV_PA_PMC_BASE + PWRGATE_STATUS);
+		if ((value & (1 << id)) == mask)
+			return 0;
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int tegra_powergate_power_on(enum tegra_powergate id)
+{
+	return tegra_powergate_set(id, true);
+}
+
+int tegra_powergate_power_off(enum tegra_powergate id)
+{
+	return tegra_powergate_set(id, false);
+}
+
+static int tegra_powergate_remove_clamping(enum tegra_powergate id)
+{
+	unsigned long value;
+
+	/*
+	 * The REMOVE_CLAMPING register has the bits for the PCIE and VDEC
+	 * partitions reversed. This was originally introduced on Tegra20 but
+	 * has since been carried forward for backwards-compatibility.
+	 */
+	if (id == TEGRA_POWERGATE_VDEC)
+		value = 1 << TEGRA_POWERGATE_PCIE;
+	else if (id == TEGRA_POWERGATE_PCIE)
+		value = 1 << TEGRA_POWERGATE_VDEC;
+	else
+		value = 1 << id;
+
+	writel(value, NV_PA_PMC_BASE + REMOVE_CLAMPING);
+
+	return 0;
+}
+
+int tegra_powergate_sequence_power_up(enum tegra_powergate id,
+				      enum periph_id periph)
+{
+	int err;
+
+	reset_set_enable(periph, 1);
+
+	err = tegra_powergate_power_on(id);
+	if (err < 0)
+		return err;
+
+	clock_enable(periph);
+
+	udelay(10);
+
+	err = tegra_powergate_remove_clamping(id);
+	if (err < 0)
+		return err;
+
+	udelay(10);
+
+	reset_set_enable(periph, 0);
+
+	return 0;
+}

arch/arm/include/asm/arch-tegra/powergate.h

@@ -0,0 +1,38 @@
+#ifndef _TEGRA_POWERGATE_H_
+#define _TEGRA_POWERGATE_H_
+
+#include <asm/arch/clock.h>
+
+enum tegra_powergate {
+	TEGRA_POWERGATE_CPU,
+	TEGRA_POWERGATE_3D,
+	TEGRA_POWERGATE_VENC,
+	TEGRA_POWERGATE_PCIE,
+	TEGRA_POWERGATE_VDEC,
+	TEGRA_POWERGATE_L2,
+	TEGRA_POWERGATE_MPE,
+	TEGRA_POWERGATE_HEG,
+	TEGRA_POWERGATE_SATA,
+	TEGRA_POWERGATE_CPU1,
+	TEGRA_POWERGATE_CPU2,
+	TEGRA_POWERGATE_CPU3,
+	TEGRA_POWERGATE_CELP,
+	TEGRA_POWERGATE_3D1,
+	TEGRA_POWERGATE_CPU0,
+	TEGRA_POWERGATE_C0NC,
+	TEGRA_POWERGATE_C1NC,
+	TEGRA_POWERGATE_SOR,
+	TEGRA_POWERGATE_DIS,
+	TEGRA_POWERGATE_DISB,
+	TEGRA_POWERGATE_XUSBA,
+	TEGRA_POWERGATE_XUSBB,
+	TEGRA_POWERGATE_XUSBC,
+	TEGRA_POWERGATE_VIC,
+	TEGRA_POWERGATE_IRAM,
+};
+
+int tegra_powergate_sequence_power_up(enum tegra_powergate id,
+				      enum periph_id periph);
+int tegra_powergate_power_off(enum tegra_powergate id);
+
+#endif

arch/arm/include/asm/arch-tegra114/powergate.h

@@ -0,0 +1,6 @@
+#ifndef _TEGRA114_POWERGATE_H_
+#define _TEGRA114_POWERGATE_H_
+
+#include <asm/arch-tegra/powergate.h>
+
+#endif /* _TEGRA114_POWERGATE_H_ */

arch/arm/include/asm/arch-tegra124/powergate.h

@@ -0,0 +1,6 @@
+#ifndef _TEGRA124_POWERGATE_H_
+#define _TEGRA124_POWERGATE_H_
+
+#include <asm/arch-tegra/powergate.h>
+
+#endif /* _TEGRA124_POWERGATE_H_ */

arch/arm/include/asm/arch-tegra20/powergate.h

@@ -0,0 +1,6 @@
+#ifndef _TEGRA20_POWERGATE_H_
+#define _TEGRA20_POWERGATE_H_
+
+#include <asm/arch-tegra/powergate.h>
+
+#endif /* _TEGRA20_POWERGATE_H_ */

arch/arm/include/asm/arch-tegra30/powergate.h

@@ -0,0 +1,6 @@
+#ifndef _TEGRA30_POWERGATE_H_
+#define _TEGRA30_POWERGATE_H_
+
+#include <asm/arch-tegra/powergate.h>
+
+#endif /* _TEGRA30_POWERGATE_H_ */