[RFC PATCH 6/7] soc: mediatek: add MT8183 dvfsrc support

[Henry Chen]

Add dvfsrc driver for MT8183

Signed-off-by: Henry Chen <henryc.chen@xxxxxxxxxxxx>
---
 drivers/soc/mediatek/Kconfig      |  15 ++
 drivers/soc/mediatek/Makefile     |   1 +
 drivers/soc/mediatek/mtk-dvfsrc.c | 473 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 489 insertions(+)
 create mode 100644 drivers/soc/mediatek/mtk-dvfsrc.c

diff --git a/drivers/soc/mediatek/Kconfig b/drivers/soc/mediatek/Kconfig
index a7d0667..f956f03 100644
--- a/drivers/soc/mediatek/Kconfig
+++ b/drivers/soc/mediatek/Kconfig
@@ -12,6 +12,21 @@ config MTK_INFRACFG
 	  INFRACFG controller contains various infrastructure registers not
 	  directly associated to any device.
 
+config MTK_DVFSRC
+	bool "MediaTek DVFSRC Support"
+	depends on ARCH_MEDIATEK
+	default ARCH_MEDIATEK
+	select REGMAP
+	select MTK_INFRACFG
+	select PM_GENERIC_DOMAINS if PM
+	depends on MTK_SCPSYS
+	help
+	  Say yes here to add support for the MediaTek DVFSRC found
+	  on different MediaTek SoCs. The DVFSRC is a proprietary
+	  hardware which is used to collect all the requests from
+	  system and turn into the decision of minimum Vcore voltage
+	  and minimum DRAM frequency to fulfill those requests.
+
 config MTK_PMIC_WRAP
 	tristate "MediaTek PMIC Wrapper Support"
 	depends on RESET_CONTROLLER
diff --git a/drivers/soc/mediatek/Makefile b/drivers/soc/mediatek/Makefile
index 9dc6670..5c010b9 100644
--- a/drivers/soc/mediatek/Makefile
+++ b/drivers/soc/mediatek/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_MTK_DVFSRC) += mtk-dvfsrc.o
 obj-$(CONFIG_MTK_INFRACFG) += mtk-infracfg.o mtk-scpsys-ext.o
 obj-$(CONFIG_MTK_PMIC_WRAP) += mtk-pmic-wrap.o
 obj-$(CONFIG_MTK_SCPSYS) += mtk-scpsys.o
diff --git a/drivers/soc/mediatek/mtk-dvfsrc.c b/drivers/soc/mediatek/mtk-dvfsrc.c
new file mode 100644
index 0000000..af462a3
--- /dev/null
+++ b/drivers/soc/mediatek/mtk-dvfsrc.c
@@ -0,0 +1,473 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 MediaTek Inc.
+ */
+#include <linux/arm-smccc.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_qos.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <soc/mediatek/mtk_sip.h>
+#include <dt-bindings/power/mt8183-power.h>
+#include <dt-bindings/soc/mtk,dvfsrc.h>
+#include "mtk-scpsys.h"
+
+#define DVFSRC_IDLE		0x00
+#define DVFSRC_GET_TARGET_LEVEL(x)	(((x) >> 0) & 0x0000ffff)
+#define DVFSRC_GET_CURRENT_LEVEL(x)	(((x) >> 16) & 0x0000ffff)
+
+/* macro for irq */
+#define DVFSRC_IRQ_TIMEOUT_EN		BIT(1)
+
+struct dvfsrc_opp {
+	int vcore_opp;
+	int dram_opp;
+};
+
+struct dvfsrc_domain {
+	int id;
+	int state;
+};
+
+struct mtk_dvfsrc;
+struct dvfsrc_soc_data {
+	const int *regs;
+	int num_opp;
+	int num_domains;
+	int dram_sft;
+	int vcore_sft;
+	const struct dvfsrc_opp **opps;
+	struct dvfsrc_domain *domains;
+	void (*init_soc)(struct mtk_dvfsrc *dvfsrc);
+	int (*get_target_level)(struct mtk_dvfsrc *dvfsrc);
+	int (*get_current_level)(struct mtk_dvfsrc *dvfsrc);
+};
+
+struct mtk_dvfsrc {
+	struct device *dev;
+	struct clk *clk_dvfsrc;
+	const struct dvfsrc_soc_data *dvd;
+	int dram_type;
+	int irq;
+	void __iomem *regs;
+	struct mutex lock;	/* generic mutex for dvfsrc driver */
+
+	struct notifier_block qos_notifier;
+	struct notifier_block scpsys_notifier;
+};
+
+static u32 dvfsrc_read(struct mtk_dvfsrc *dvfs, u32 offset)
+{
+	return readl(dvfs->regs + dvfs->dvd->regs[offset]);
+}
+
+static void dvfsrc_write(struct mtk_dvfsrc *dvfs, u32 offset, u32 val)
+{
+	writel(val, dvfs->regs + dvfs->dvd->regs[offset]);
+}
+
+enum dvfsrc_regs {
+	DVFSRC_BASIC_CONTROL,
+	DVFSRC_SW_REQ,
+	DVFSRC_SW_REQ2,
+	DVFSRC_EMI_REQUEST,
+	DVFSRC_EMI_REQUEST2,
+	DVFSRC_EMI_REQUEST3,
+	DVFSRC_EMI_QOS0,
+	DVFSRC_EMI_QOS1,
+	DVFSRC_EMI_QOS2,
+	DVFSRC_EMI_MD2SPM0,
+	DVFSRC_EMI_MD2SPM1,
+	DVFSRC_VCORE_REQUEST,
+	DVFSRC_VCORE_REQUEST2,
+	DVFSRC_VCORE_MD2SPM0,
+	DVFSRC_INT,
+	DVFSRC_INT_EN,
+	DVFSRC_INT_CLR,
+	DVFSRC_TIMEOUT_NEXTREQ,
+	DVFSRC_LEVEL,
+	DVFSRC_LEVEL_LABEL_0_1,
+	DVFSRC_LEVEL_LABEL_2_3,
+	DVFSRC_LEVEL_LABEL_4_5,
+	DVFSRC_LEVEL_LABEL_6_7,
+	DVFSRC_LEVEL_LABEL_8_9,
+	DVFSRC_LEVEL_LABEL_10_11,
+	DVFSRC_LEVEL_LABEL_12_13,
+	DVFSRC_LEVEL_LABEL_14_15,
+	DVFSRC_SW_BW_0,
+	DVFSRC_QOS_EN,
+	DVFSRC_FORCE,
+	DVFSRC_LAST,
+	DVFSRC_RSRV_0,
+	DVFSRC_RSRV_1,
+};
+
+static int mt8183_regs[] = {
+	[DVFSRC_BASIC_CONTROL] =	0x0,
+	[DVFSRC_SW_REQ] =		0x4,
+	[DVFSRC_SW_REQ2] =		0x8,
+	[DVFSRC_EMI_REQUEST] =		0xC,
+	[DVFSRC_EMI_REQUEST2] =		0x10,
+	[DVFSRC_EMI_REQUEST3] =		0x14,
+	[DVFSRC_EMI_QOS0] =		0x24,
+	[DVFSRC_EMI_QOS1] =		0x28,
+	[DVFSRC_EMI_QOS2] =		0x2C,
+	[DVFSRC_EMI_MD2SPM0] =		0x30,
+	[DVFSRC_EMI_MD2SPM1] =		0x34,
+	[DVFSRC_VCORE_REQUEST] =	0x48,
+	[DVFSRC_VCORE_REQUEST2] =	0x4C,
+	[DVFSRC_VCORE_MD2SPM0] =	0x68,
+	[DVFSRC_INT] =			0x98,
+	[DVFSRC_INT_EN] =		0x9C,
+	[DVFSRC_INT_CLR] =		0xA0,
+	[DVFSRC_TIMEOUT_NEXTREQ] =	0xD8,
+	[DVFSRC_LEVEL] =		0xDC,
+	[DVFSRC_LEVEL_LABEL_0_1] =	0xE0,
+	[DVFSRC_LEVEL_LABEL_2_3] =	0xE4,
+	[DVFSRC_LEVEL_LABEL_4_5] =	0xE8,
+	[DVFSRC_LEVEL_LABEL_6_7] =	0xEC,
+	[DVFSRC_LEVEL_LABEL_8_9] =	0xF0,
+	[DVFSRC_LEVEL_LABEL_10_11] =	0xF4,
+	[DVFSRC_LEVEL_LABEL_12_13] =	0xF8,
+	[DVFSRC_LEVEL_LABEL_14_15] =	0xFC,
+	[DVFSRC_SW_BW_0] =		0x160,
+	[DVFSRC_QOS_EN] =		0x180,
+	[DVFSRC_FORCE] =		0x300,
+	[DVFSRC_LAST] =			0x308,
+	[DVFSRC_RSRV_0] =		0x600,
+	[DVFSRC_RSRV_1] =		0x604,
+};
+
+static bool dvfsrc_is_idle(struct mtk_dvfsrc *dvfsrc)
+{
+	int val = 0;
+
+	if (dvfsrc->dvd->get_target_level)
+		val = dvfsrc->dvd->get_target_level(dvfsrc);
+
+	return val == DVFSRC_IDLE;
+}
+
+static int dvfsrc_wait_for_state(struct mtk_dvfsrc *dvfsrc,
+				 bool (*fp)(struct mtk_dvfsrc *))
+{
+	unsigned long timeout;
+
+	timeout = jiffies + usecs_to_jiffies(1000);
+
+	do {
+		if (fp(dvfsrc))
+			return 0;
+	} while (!time_after(jiffies, timeout));
+
+	return -ETIMEDOUT;
+}
+
+static void mtk_dvfsrc_mt8183_init(struct mtk_dvfsrc *dvfsrc)
+{
+	struct arm_smccc_res res;
+
+	mutex_lock(&dvfsrc->lock);
+
+	arm_smccc_smc(MTK_SIP_SPM, MTK_SIP_SPM_DVFSRC_INIT, 0, 0, 0, 0, 0, 0,
+		      &res);
+
+	dvfsrc_write(dvfsrc, DVFSRC_LEVEL_LABEL_0_1, 0x00100000);
+
+	dvfsrc_write(dvfsrc, DVFSRC_LEVEL_LABEL_2_3, 0x00210011);
+	dvfsrc_write(dvfsrc, DVFSRC_LEVEL_LABEL_4_5, 0x01100100);
+	dvfsrc_write(dvfsrc, DVFSRC_LEVEL_LABEL_6_7, 0x01210111);
+	dvfsrc_write(dvfsrc, DVFSRC_LEVEL_LABEL_8_9, 0x02100200);
+	dvfsrc_write(dvfsrc, DVFSRC_LEVEL_LABEL_10_11, 0x02210211);
+	dvfsrc_write(dvfsrc, DVFSRC_LEVEL_LABEL_12_13, 0x03210321);
+	dvfsrc_write(dvfsrc, DVFSRC_LEVEL_LABEL_14_15, 0x03210321);
+
+	/* EMI/VCORE HRT, MD2SPM, BW setting */
+	dvfsrc_write(dvfsrc, DVFSRC_EMI_QOS0, 0x32);
+	dvfsrc_write(dvfsrc, DVFSRC_EMI_QOS1, 0x66);
+	dvfsrc_write(dvfsrc, DVFSRC_EMI_MD2SPM0, 0x80F8);
+	dvfsrc_write(dvfsrc, DVFSRC_EMI_MD2SPM1, 0x0);
+	dvfsrc_write(dvfsrc, DVFSRC_VCORE_MD2SPM0, 0x80C0);
+
+	dvfsrc_write(dvfsrc, DVFSRC_RSRV_1, 0x0000001C);
+	dvfsrc_write(dvfsrc, DVFSRC_TIMEOUT_NEXTREQ, 0x00000013);
+	dvfsrc_write(dvfsrc, DVFSRC_INT_EN, 0x2);
+
+	dvfsrc_write(dvfsrc, DVFSRC_EMI_REQUEST, 0x00290209);
+	dvfsrc_write(dvfsrc, DVFSRC_EMI_REQUEST2, 0);
+
+	dvfsrc_write(dvfsrc, DVFSRC_VCORE_REQUEST, 0x00150000);
+
+	dvfsrc_write(dvfsrc, DVFSRC_QOS_EN, 0x0000407F);
+	dvfsrc_write(dvfsrc, DVFSRC_EMI_REQUEST3, 0x09000000);
+
+	dvfsrc_write(dvfsrc, DVFSRC_FORCE, 0x00400000);
+	dvfsrc_write(dvfsrc, DVFSRC_BASIC_CONTROL, 0x0000C07B);
+	dvfsrc_write(dvfsrc, DVFSRC_BASIC_CONTROL, 0x0000017B);
+
+	dvfsrc_write(dvfsrc, DVFSRC_VCORE_REQUEST,
+		     (dvfsrc_read(dvfsrc, DVFSRC_VCORE_REQUEST)
+		     & ~(0x3 << 20)));
+	dvfsrc_write(dvfsrc, DVFSRC_EMI_REQUEST,
+		     (dvfsrc_read(dvfsrc, DVFSRC_EMI_REQUEST)
+		     & ~(0x3 << 20)));
+
+	mutex_unlock(&dvfsrc->lock);
+}
+
+static int mt8183_get_target_level(struct mtk_dvfsrc *dvfsrc)
+{
+	return DVFSRC_GET_TARGET_LEVEL(dvfsrc_read(dvfsrc, DVFSRC_LEVEL));
+}
+
+static int mt8183_get_current_level(struct mtk_dvfsrc *dvfsrc)
+{
+	return DVFSRC_GET_CURRENT_LEVEL(dvfsrc_read(dvfsrc, DVFSRC_LEVEL));
+}
+
+static int get_cur_performance_level(struct mtk_dvfsrc *dvfsrc)
+{
+	int bit = 0;
+
+	if (dvfsrc->dvd->get_current_level)
+		bit = dvfsrc->dvd->get_current_level(dvfsrc);
+
+	return ffs(bit);
+}
+
+static int pm_qos_memory_bw_notify(struct notifier_block *b,
+				   unsigned long bw, void *v)
+{
+	struct mtk_dvfsrc *dvfsrc;
+
+	dvfsrc = container_of(b, struct mtk_dvfsrc, qos_notifier);
+	mutex_lock(&dvfsrc->lock);
+
+	dev_dbg(dvfsrc->dev, "data: 0x%lx\n", bw);
+	dvfsrc_write(dvfsrc, DVFSRC_SW_BW_0, bw / 100);
+
+	mutex_unlock(&dvfsrc->lock);
+
+	return NOTIFY_OK;
+}
+
+static int dvfsrc_set_performace(struct notifier_block *b,
+				 unsigned long l, void *v)
+{
+	int i, val, highest = 0, vcore_opp = 0, dram_opp = 0;
+	struct mtk_dvfsrc *dvfsrc;
+	struct scp_event_data *sc = v;
+	struct dvfsrc_domain *d;
+
+	if (sc->event_type != MTK_SCPSYS_PSTATE)
+		return 0;
+
+	dvfsrc = container_of(b, struct mtk_dvfsrc, scpsys_notifier);
+
+	mutex_lock(&dvfsrc->lock);
+	d = dvfsrc->dvd->domains;
+
+	if (l > dvfsrc->dvd->num_opp || l <= 0) {
+		dev_err(dvfsrc->dev, "pstate out of range = %ld\n", l);
+		goto out;
+	}
+
+	for (i = 0, highest = 0; i < dvfsrc->dvd->num_domains - 1; i++, d++) {
+		if (sc->domain_id == d->id)
+			d->state = l;
+		if (d->state > highest)
+			highest = d->state;
+	}
+
+	if (highest == 0) {
+		dev_err(dvfsrc->dev, "domain not match\n");
+		goto out;
+	}
+
+	/* translate pstate to dvfsrc level, and set it to DVFSRC HW */
+	vcore_opp =
+		dvfsrc->dvd->opps[dvfsrc->dram_type][highest - 1].vcore_opp;
+	dram_opp = dvfsrc->dvd->opps[dvfsrc->dram_type][highest - 1].dram_opp;
+
+	if (dvfsrc_wait_for_state(dvfsrc, dvfsrc_is_idle)) {
+		dev_warn(dvfsrc->dev, "[%s] wait idle, last: %d -> %d\n",
+			 __func__, dvfsrc_read(dvfsrc, DVFSRC_LEVEL),
+		dvfsrc_read(dvfsrc, DVFSRC_LAST));
+		goto out;
+	}
+
+	dvfsrc_write(dvfsrc, DVFSRC_SW_REQ,
+		     dram_opp << dvfsrc->dvd->dram_sft |
+		     vcore_opp << dvfsrc->dvd->vcore_sft);
+
+	if (dvfsrc_wait_for_state(dvfsrc, dvfsrc_is_idle)) {
+		dev_warn(dvfsrc->dev, "[%s] wait idle, last: %d -> %d\n",
+			 __func__, dvfsrc_read(dvfsrc, DVFSRC_LEVEL),
+			 dvfsrc_read(dvfsrc, DVFSRC_LAST));
+		goto out;
+	}
+
+	val = get_cur_performance_level(dvfsrc);
+	if (val < highest) {
+		dev_err(dvfsrc->dev, "current: %d < hightest: %x\n",
+			highest, val);
+	}
+out:
+	mutex_unlock(&dvfsrc->lock);
+
+	return 0;
+}
+
+static void pstate_notifier_register(struct mtk_dvfsrc *dvfsrc)
+{
+	dvfsrc->scpsys_notifier.notifier_call = dvfsrc_set_performace;
+	register_scpsys_notifier(&dvfsrc->scpsys_notifier);
+}
+
+static void pm_qos_notifier_register(struct mtk_dvfsrc *dvfsrc)
+{
+	dvfsrc->qos_notifier.notifier_call = pm_qos_memory_bw_notify;
+	pm_qos_add_notifier(PM_QOS_MEMORY_BANDWIDTH, &dvfsrc->qos_notifier);
+}
+
+static irqreturn_t mtk_dvfsrc_interrupt(int irq, void *dev_id)
+{
+	u32 val;
+	struct mtk_dvfsrc *dvfsrc = dev_id;
+
+	val = dvfsrc_read(dvfsrc, DVFSRC_INT);
+	dvfsrc_write(dvfsrc, DVFSRC_INT_CLR, val);
+	dvfsrc_write(dvfsrc, DVFSRC_INT_CLR, 0x0);
+	if (val & DVFSRC_IRQ_TIMEOUT_EN)
+		dev_warn(dvfsrc->dev, "timeout at spm = %x", val);
+
+	return IRQ_HANDLED;
+}
+
+static int mtk_dvfsrc_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct mtk_dvfsrc *dvfsrc;
+	int ret;
+
+	dvfsrc = devm_kzalloc(&pdev->dev, sizeof(*dvfsrc), GFP_KERNEL);
+	if (!dvfsrc)
+		return -ENOMEM;
+
+	dvfsrc->dvd = of_device_get_match_data(&pdev->dev);
+	dvfsrc->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	dvfsrc->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(dvfsrc->regs))
+		return PTR_ERR(dvfsrc->regs);
+
+	dvfsrc->clk_dvfsrc = devm_clk_get(dvfsrc->dev, "dvfsrc");
+	if (IS_ERR(dvfsrc->clk_dvfsrc)) {
+		dev_err(dvfsrc->dev, "failed to get clock: %ld\n",
+			PTR_ERR(dvfsrc->clk_dvfsrc));
+		return PTR_ERR(dvfsrc->clk_dvfsrc);
+	}
+
+	ret = clk_prepare_enable(dvfsrc->clk_dvfsrc);
+	if (ret)
+		return ret;
+
+	ret = of_property_read_u32(dvfsrc->dev->of_node, "dram_type",
+				   &dvfsrc->dram_type);
+	if (ret) {
+		dev_err(dvfsrc->dev, "failed to get dram_type: %d\n", ret);
+		clk_disable_unprepare(dvfsrc->clk_dvfsrc);
+		return ret;
+	}
+
+	dvfsrc->irq = platform_get_irq(pdev, 0);
+	ret = request_irq(dvfsrc->irq, mtk_dvfsrc_interrupt
+		, IRQF_TRIGGER_HIGH, "dvfsrc", dvfsrc);
+	if (ret)
+		dev_dbg(dvfsrc->dev, "interrupt not use\n");
+
+	mutex_init(&dvfsrc->lock);
+	if (dvfsrc->dvd->init_soc)
+		dvfsrc->dvd->init_soc(dvfsrc);
+
+	pstate_notifier_register(dvfsrc);
+	pm_qos_notifier_register(dvfsrc);
+	platform_set_drvdata(pdev, dvfsrc);
+
+	return 0;
+}
+
+static const struct dvfsrc_opp dvfsrc_opp_mt8183_lp4[] = {
+	{0, 0}, {1, 0}, {1, 1}, {1, 2},
+};
+
+static const struct dvfsrc_opp dvfsrc_opp_mt8183_1p3[] = {
+	{0, 0}, {0, 1}, {1, 1}, {1, 2},
+};
+
+static const struct dvfsrc_opp *dvfsrc_opp_mt8183[] = {
+	[MT8183_DVFSRC_OPP_LP4] = dvfsrc_opp_mt8183_lp4,
+	[MT8183_DVFSRC_OPP_LP4X] = dvfsrc_opp_mt8183_1p3,
+	[MT8183_DVFSRC_OPP_LP3] = dvfsrc_opp_mt8183_1p3,
+};
+
+static struct dvfsrc_domain dvfsrc_domains_mt8183[] = {
+	{MT8183_POWER_DOMAIN_MFG_ASYNC, 0},
+	{MT8183_POWER_DOMAIN_MFG, 0},
+	{MT8183_POWER_DOMAIN_CAM, 0},
+	{MT8183_POWER_DOMAIN_DISP, 0},
+	{MT8183_POWER_DOMAIN_ISP, 0},
+	{MT8183_POWER_DOMAIN_VDEC, 0},
+	{MT8183_POWER_DOMAIN_VENC, 0},
+};
+
+static const struct dvfsrc_soc_data mt8183_data = {
+	.opps = dvfsrc_opp_mt8183,
+	.num_opp = ARRAY_SIZE(dvfsrc_opp_mt8183_lp4),
+	.regs = mt8183_regs,
+	.domains = dvfsrc_domains_mt8183,
+	.num_domains = ARRAY_SIZE(dvfsrc_domains_mt8183),
+	.init_soc = mtk_dvfsrc_mt8183_init,
+	.get_target_level = mt8183_get_target_level,
+	.get_current_level = mt8183_get_current_level,
+	.dram_sft = 0,
+	.vcore_sft = 2,
+};
+
+static int mtk_dvfsrc_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id mtk_dvfsrc_of_match[] = {
+	{
+		.compatible = "mediatek,mt8183-dvfsrc",
+		.data = &mt8183_data,
+	}, {
+		/* sentinel */
+	},
+};
+
+static struct platform_driver mtk_dvfsrc_driver = {
+	.probe	= mtk_dvfsrc_probe,
+	.remove	= mtk_dvfsrc_remove,
+	.driver = {
+		.name = "mtk-dvfsrc",
+		.of_match_table = of_match_ptr(mtk_dvfsrc_of_match),
+	},
+};
+
+builtin_platform_driver(mtk_dvfsrc_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MTK DVFSRC driver");
-- 
1.9.1