[PATCH v1 3/4] soc: starfive: Add StarFive JH71XX pmu driver

[Walker Chen <walker.chen@starfivetech.com>]

Add generic power domain driver for the StarFive JH71XX SoC.

Signed-off-by: Walker Chen <walker.chen@starfivetech.com>
---
 MAINTAINERS                       |   8 +
 drivers/soc/Kconfig               |   1 +
 drivers/soc/Makefile              |   1 +
 drivers/soc/starfive/Kconfig      |   9 +
 drivers/soc/starfive/Makefile     |   3 +
 drivers/soc/starfive/jh71xx_pmu.c | 380 ++++++++++++++++++++++++++++++
 include/soc/starfive/pm_domains.h |  15 ++
 7 files changed, 417 insertions(+)
 create mode 100644 drivers/soc/starfive/Kconfig
 create mode 100644 drivers/soc/starfive/Makefile
 create mode 100644 drivers/soc/starfive/jh71xx_pmu.c
 create mode 100644 include/soc/starfive/pm_domains.h

diff --git a/MAINTAINERS b/MAINTAINERS
index a70c1d0f303e..112f1e698723 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19623,6 +19623,14 @@ F:	Documentation/devicetree/bindings/reset/starfive,jh7100-reset.yaml
 F:	drivers/reset/starfive/
 F:	include/dt-bindings/reset/starfive*
 
+STARFIVE JH71XX PMU CONTROLLER DRIVER
+M:	Walker Chen <walker.chen@starfivetech.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/power/starfive*
+F:	drivers/soc/starfive/jh71xx_pmu.c
+F:	include/soc/starfive/pm_domains.h
+F:	include/dt-bindings/power/jh7110-power.h
+
 STATIC BRANCH/CALL
 M:	Peter Zijlstra <peterz@infradead.org>
 M:	Josh Poimboeuf <jpoimboe@kernel.org>
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index e461c071189b..628fda4d5ed9 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -21,6 +21,7 @@ source "drivers/soc/renesas/Kconfig"
 source "drivers/soc/rockchip/Kconfig"
 source "drivers/soc/samsung/Kconfig"
 source "drivers/soc/sifive/Kconfig"
+source "drivers/soc/starfive/Kconfig"
 source "drivers/soc/sunxi/Kconfig"
 source "drivers/soc/tegra/Kconfig"
 source "drivers/soc/ti/Kconfig"
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 534669840858..cbe076f42068 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -27,6 +27,7 @@ obj-y				+= renesas/
 obj-y				+= rockchip/
 obj-$(CONFIG_SOC_SAMSUNG)	+= samsung/
 obj-y				+= sifive/
+obj-y				+= starfive/
 obj-y				+= sunxi/
 obj-$(CONFIG_ARCH_TEGRA)	+= tegra/
 obj-y				+= ti/
diff --git a/drivers/soc/starfive/Kconfig b/drivers/soc/starfive/Kconfig
new file mode 100644
index 000000000000..2bbcc1397b15
--- /dev/null
+++ b/drivers/soc/starfive/Kconfig
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config JH71XX_PMU
+	bool "Support PMU for StarFive JH71XX Soc"
+	depends on PM && (SOC_STARFIVE || COMPILE_TEST)
+	select PM_GENERIC_DOMAINS
+	help
+	  Say y here to enable power domain support.
+
diff --git a/drivers/soc/starfive/Makefile b/drivers/soc/starfive/Makefile
new file mode 100644
index 000000000000..13b589d6b5f3
--- /dev/null
+++ b/drivers/soc/starfive/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_JH71XX_PMU)	+= jh71xx_pmu.o
diff --git a/drivers/soc/starfive/jh71xx_pmu.c b/drivers/soc/starfive/jh71xx_pmu.c
new file mode 100644
index 000000000000..e6c0083d166e
--- /dev/null
+++ b/drivers/soc/starfive/jh71xx_pmu.c
@@ -0,0 +1,380 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * StarFive JH71XX Power Domain Controller Driver
+ *
+ * Copyright (C) 2022 StarFive Technology Co., Ltd.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <dt-bindings/power/jh7110-power.h>
+
+/* register offset */
+#define HW_EVENT_TURN_ON_MASK		0x04
+#define HW_EVENT_TURN_OFF_MASK		0x08
+#define SW_TURN_ON_POWER_MODE		0x0C
+#define SW_TURN_OFF_POWER_MODE		0x10
+#define SW_ENCOURAGE			0x44
+#define PMU_INT_MASK			0x48
+#define PCH_BYPASS			0x4C
+#define PCH_PSTATE			0x50
+#define PCH_TIMEOUT			0x54
+#define LP_TIMEOUT			0x58
+#define HW_TURN_ON_MODE			0x5C
+#define CURR_POWER_MODE			0x80
+#define PMU_EVENT_STATUS		0x88
+#define PMU_INT_STATUS			0x8C
+
+/* sw encourage cfg */
+#define SW_MODE_ENCOURAGE_EN_LO		0x05
+#define SW_MODE_ENCOURAGE_EN_HI		0x50
+#define SW_MODE_ENCOURAGE_DIS_LO	0x0A
+#define SW_MODE_ENCOURAGE_DIS_HI	0xA0
+#define SW_MODE_ENCOURAGE_ON		0xFF
+
+/* pmu int status */
+#define PMU_INT_SEQ_DONE		BIT(0)
+#define PMU_INT_HW_REQ			BIT(1)
+#define PMU_INT_SW_FAIL			GENMASK(3, 2)
+#define PMU_INT_HW_FAIL			GENMASK(5, 4)
+#define PMU_INT_PCH_FAIL		GENMASK(8, 6)
+#define PMU_INT_FAIL_MASK		(PMU_INT_SW_FAIL | \
+					PMU_INT_HW_FAIL | \
+					PMU_INT_PCH_FAIL)
+#define PMU_INT_ALL_MASK		(PMU_INT_SEQ_DONE | \
+					PMU_INT_HW_REQ | \
+					PMU_INT_FAIL_MASK)
+
+#define DELAY_US			10
+#define TIMEOUT_US			100000
+
+struct starfive_power_dev {
+	struct generic_pm_domain genpd;
+	struct starfive_pmu *power;
+	uint32_t mask;
+};
+
+struct starfive_pmu {
+	void __iomem *base;
+	spinlock_t lock;
+	int irq;
+	struct device *pdev;
+	struct starfive_power_dev *dev;
+	struct genpd_onecell_data genpd_data;
+	struct generic_pm_domain **genpd;
+};
+
+struct starfive_pmu_data {
+	const char * const name;
+	uint8_t bit;
+	unsigned int flags;
+};
+
+static void __iomem *pmu_base;
+
+static inline void pmu_writel(u32 val, u32 offset)
+{
+	writel(val, pmu_base + offset);
+}
+
+void starfive_pmu_hw_event_turn_on(u32 mask)
+{
+	pmu_writel(mask, HW_EVENT_TURN_ON_MASK);
+}
+EXPORT_SYMBOL(starfive_pmu_hw_event_turn_on);
+
+void starfive_pmu_hw_event_turn_off(u32 mask)
+{
+	pmu_writel(mask, HW_EVENT_TURN_OFF_MASK);
+}
+EXPORT_SYMBOL(starfive_pmu_hw_event_turn_off);
+
+static int starfive_pmu_get_state(struct starfive_power_dev *pmd, bool *is_on)
+{
+	struct starfive_pmu *pmu = pmd->power;
+
+	if (!pmd->mask) {
+		*is_on = false;
+		return -EINVAL;
+	}
+
+	*is_on = __raw_readl(pmu->base + CURR_POWER_MODE) & pmd->mask;
+
+	return 0;
+}
+
+static int starfive_pmu_set_state(struct starfive_power_dev *pmd, bool on)
+{
+	struct starfive_pmu *pmu = pmd->power;
+	unsigned long flags;
+	uint32_t val;
+	uint32_t mode;
+	uint32_t encourage_lo;
+	uint32_t encourage_hi;
+	bool is_on;
+	int ret;
+
+	if (!pmd->mask)
+		return -EINVAL;
+
+	if (is_on == on) {
+		dev_info(pmu->pdev, "pm domain [%s] is already %sable status.\n",
+				pmd->genpd.name, on ? "en" : "dis");
+		return 0;
+	}
+
+	spin_lock_irqsave(&pmu->lock, flags);
+
+	if (on) {
+		mode = SW_TURN_ON_POWER_MODE;
+		encourage_lo = SW_MODE_ENCOURAGE_EN_LO;
+		encourage_hi = SW_MODE_ENCOURAGE_EN_HI;
+	} else {
+		mode = SW_TURN_OFF_POWER_MODE;
+		encourage_lo = SW_MODE_ENCOURAGE_DIS_LO;
+		encourage_hi = SW_MODE_ENCOURAGE_DIS_HI;
+	}
+
+	__raw_writel(pmd->mask, pmu->base + mode);
+
+	/* write SW_ENCOURAGE to make the configuration take effect */
+	__raw_writel(SW_MODE_ENCOURAGE_ON, pmu->base + SW_ENCOURAGE);
+	__raw_writel(encourage_lo, pmu->base + SW_ENCOURAGE);
+	__raw_writel(encourage_hi, pmu->base + SW_ENCOURAGE);
+
+	spin_unlock_irqrestore(&pmu->lock, flags);
+
+	if (on) {
+		ret = readl_poll_timeout_atomic(pmu->base + CURR_POWER_MODE, val,
+						val & pmd->mask, DELAY_US,
+						TIMEOUT_US);
+		if (ret) {
+			dev_err(pmu->pdev, "%s: failed to power on\n", pmd->genpd.name);
+			return -ETIMEDOUT;
+		}
+	} else {
+		ret = readl_poll_timeout_atomic(pmu->base + CURR_POWER_MODE, val,
+						!(val & pmd->mask), DELAY_US,
+						TIMEOUT_US);
+		if (ret) {
+			dev_err(pmu->pdev, "%s: failed to power off\n", pmd->genpd.name);
+			return -ETIMEDOUT;
+		}
+	}
+
+	return 0;
+}
+
+static int starfive_pmu_on(struct generic_pm_domain *genpd)
+{
+	struct starfive_power_dev *pmd = container_of(genpd,
+		struct starfive_power_dev, genpd);
+
+	return starfive_pmu_set_state(pmd, true);
+}
+
+static int starfive_pmu_off(struct generic_pm_domain *genpd)
+{
+	struct starfive_power_dev *pmd = container_of(genpd,
+		struct starfive_power_dev, genpd);
+
+	return starfive_pmu_set_state(pmd, false);
+}
+
+static void starfive_pmu_int_enable(struct starfive_pmu *pmu, u32 mask, bool enable)
+{
+	u32 val = __raw_readl(pmu->base + PMU_INT_MASK);
+
+	if (enable)
+		val &= ~mask;
+	else
+		val |= mask;
+
+	__raw_writel(val, pmu->base + PMU_INT_MASK);
+}
+
+static irqreturn_t starfive_pmu_interrupt(int irq, void *data)
+{
+	struct starfive_pmu *pmu = data;
+	unsigned long flags;
+	u32 val;
+
+	spin_lock_irqsave(&pmu->lock, flags);
+	val = __raw_readl(pmu->base + PMU_INT_STATUS);
+
+	if (val & PMU_INT_SEQ_DONE)
+		dev_dbg(pmu->pdev, "sequence done.\n");
+	if (val & PMU_INT_HW_REQ)
+		dev_dbg(pmu->pdev, "hardware encourage requestion.\n");
+	if (val & PMU_INT_SW_FAIL)
+		dev_err(pmu->pdev, "software encourage fail.\n");
+	if (val & PMU_INT_HW_FAIL)
+		dev_err(pmu->pdev, "hardware encourage fail.\n");
+	if (val & PMU_INT_PCH_FAIL)
+		dev_err(pmu->pdev, "p-channel fail event.\n");
+
+	/* clear interrupts */
+	__raw_writel(val, pmu->base + PMU_INT_STATUS);
+	__raw_writel(val, pmu->base + PMU_EVENT_STATUS);
+
+	spin_unlock_irqrestore(&pmu->lock, flags);
+
+	return IRQ_HANDLED;
+}
+
+static int starfive_pmu_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	const struct starfive_pmu_data *entry, *table;
+	struct starfive_pmu *pmu;
+	unsigned int i;
+	uint8_t max_bit = 0;
+	int ret;
+
+	pmu = devm_kzalloc(dev, sizeof(*pmu), GFP_KERNEL);
+	if (!pmu)
+		return -ENOMEM;
+
+	pmu_base = pmu->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(pmu->base))
+		return PTR_ERR(pmu->base);
+
+	/* initialize pmu interrupt  */
+	pmu->irq = platform_get_irq(pdev, 0);
+	if (pmu->irq < 0)
+		return pmu->irq;
+
+	ret = devm_request_irq(dev, pmu->irq, starfive_pmu_interrupt,
+			       0, pdev->name, pmu);
+	if (ret)
+		dev_err(dev, "request irq failed.\n");
+
+	table = of_device_get_match_data(dev);
+	if (!table)
+		return -EINVAL;
+
+	pmu->pdev = dev;
+	pmu->genpd_data.num_domains = 0;
+	i = 0;
+	for (entry = table; entry->name; entry++) {
+		max_bit = max(max_bit, entry->bit);
+		i++;
+	}
+
+	if (!i)
+		return -ENODEV;
+
+	pmu->genpd_data.num_domains = max_bit + 1;
+
+	pmu->dev = devm_kcalloc(dev, pmu->genpd_data.num_domains,
+				  sizeof(struct starfive_power_dev),
+				  GFP_KERNEL);
+	if (!pmu->dev)
+		return -ENOMEM;
+
+	pmu->genpd = devm_kcalloc(dev, pmu->genpd_data.num_domains,
+				    sizeof(struct generic_pm_domain *),
+				    GFP_KERNEL);
+	if (!pmu->genpd)
+		return -ENOMEM;
+
+	pmu->genpd_data.domains = pmu->genpd;
+
+	i = 0;
+	for (entry = table; entry->name; entry++) {
+		struct starfive_power_dev *pmd = &pmu->dev[i];
+		bool is_on;
+
+		pmd->power = pmu;
+		pmd->mask = BIT(entry->bit);
+		pmd->genpd.name = entry->name;
+		pmd->genpd.flags = entry->flags;
+
+		ret = starfive_pmu_get_state(pmd, &is_on);
+		if (ret)
+			dev_warn(dev, "unable to get current state for %s\n",
+				 pmd->genpd.name);
+
+		pmd->genpd.power_on = starfive_pmu_on;
+		pmd->genpd.power_off = starfive_pmu_off;
+
+		pm_genpd_init(&pmd->genpd, NULL, !is_on);
+		pmu->genpd[entry->bit] = &pmd->genpd;
+
+		i++;
+	}
+
+	spin_lock_init(&pmu->lock);
+	starfive_pmu_int_enable(pmu, PMU_INT_ALL_MASK & ~PMU_INT_PCH_FAIL, true);
+
+	ret = of_genpd_add_provider_onecell(np, &pmu->genpd_data);
+	if (ret) {
+		dev_err(dev, "failed to register genpd driver: %d\n", ret);
+		return ret;
+	}
+
+	dev_info(dev, "registered %u power domains\n", i);
+
+	return 0;
+}
+
+static const struct starfive_pmu_data jh7110_power_domains[] = {
+	{
+		.name = "SYSTOP",
+		.bit = JH7110_PD_SYSTOP,
+		.flags = GENPD_FLAG_ALWAYS_ON,
+	}, {
+		.name = "CPU",
+		.bit = JH7110_PD_CPU,
+		.flags = GENPD_FLAG_ALWAYS_ON,
+	}, {
+		.name = "GPUA",
+		.bit = JH7110_PD_GPUA,
+	}, {
+		.name = "VDEC",
+		.bit = JH7110_PD_VDEC,
+	}, {
+		.name = "VOUT",
+		.bit = JH7110_PD_VOUT,
+	}, {
+		.name = "ISP",
+		.bit = JH7110_PD_ISP,
+	}, {
+		.name = "VENC",
+		.bit = JH7110_PD_VENC,
+	}, {
+		.name = "GPUB",
+		.bit = JH7110_PD_GPUB,
+	}, {
+		/* sentinel */
+	},
+};
+
+static const struct of_device_id starfive_pmu_of_match[] = {
+	{
+		.compatible = "starfive,jh7110-pmu",
+		.data = &jh7110_power_domains,
+	}, {
+		/* sentinel */
+	}
+};
+
+static struct platform_driver jh71xx_pmu_driver = {
+	.driver = {
+		.name = "jh71xx-pmu",
+		.of_match_table = starfive_pmu_of_match,
+	},
+	.probe  = starfive_pmu_probe,
+};
+builtin_platform_driver(jh71xx_pmu_driver);
+
+MODULE_AUTHOR("Walker Chen <walker.chen@starfivetech.com>");
+MODULE_DESCRIPTION("StarFive JH71XX Power Domain Driver");
+MODULE_LICENSE("GPL");
diff --git a/include/soc/starfive/pm_domains.h b/include/soc/starfive/pm_domains.h
new file mode 100644
index 000000000000..a20e28e9baf3
--- /dev/null
+++ b/include/soc/starfive/pm_domains.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022 StarFive Technology Co., Ltd.
+ * Author: Walker Chen <walker.chen@starfivetech.com>
+ */
+
+#ifndef __SOC_STARFIVE_PMDOMAINS_H__
+#define __SOC_STARFIVE_PMDOMAINS_H__
+
+#include <linux/types.h>
+
+void starfive_pmu_hw_event_turn_on(u32 mask);
+void starfive_pmu_hw_event_turn_off(u32 mask);
+
+#endif /* __SOC_STARFIVE_PMDOMAINS_H__ */
-- 
2.17.1