1 files changed, 702 insertions, 0 deletions

diff --git a/drivers/soc/qcom/icc-bwmon.c b/drivers/soc/qcom/icc-bwmon.c
new file mode 100644
index 000000000..782954999
--- /dev/null
+++ b/drivers/soc/qcom/icc-bwmon.c
@@ -0,0 +1,702 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014-2018, The Linux Foundation. All rights reserved.
+ * Copyright (C) 2021-2022 Linaro Ltd
+ * Author: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>, based on
+ *         previous work of Thara Gopinath and msm-4.9 downstream sources.
+ */
+
+#include <linux/err.h>
+#include <linux/interconnect.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/regmap.h>
+#include <linux/sizes.h>
+
+/*
+ * The BWMON samples data throughput within 'sample_ms' time. With three
+ * configurable thresholds (Low, Medium and High) gives four windows (called
+ * zones) of current bandwidth:
+ *
+ * Zone 0: byte count < THRES_LO
+ * Zone 1: THRES_LO < byte count < THRES_MED
+ * Zone 2: THRES_MED < byte count < THRES_HIGH
+ * Zone 3: THRES_HIGH < byte count
+ *
+ * Zones 0 and 2 are not used by this driver.
+ */
+
+/* Internal sampling clock frequency */
+#define HW_TIMER_HZ				19200000
+
+#define BWMON_V4_GLOBAL_IRQ_CLEAR		0x008
+#define BWMON_V4_GLOBAL_IRQ_ENABLE		0x00c
+/*
+ * All values here and further are matching regmap fields, so without absolute
+ * register offsets.
+ */
+#define BWMON_V4_GLOBAL_IRQ_ENABLE_ENABLE	BIT(0)
+
+#define BWMON_V4_IRQ_STATUS			0x100
+#define BWMON_V4_IRQ_CLEAR			0x108
+
+#define BWMON_V4_IRQ_ENABLE			0x10c
+#define BWMON_IRQ_ENABLE_MASK			(BIT(1) | BIT(3))
+#define BWMON_V5_IRQ_STATUS			0x000
+#define BWMON_V5_IRQ_CLEAR			0x008
+#define BWMON_V5_IRQ_ENABLE			0x00c
+
+#define BWMON_V4_ENABLE				0x2a0
+#define BWMON_V5_ENABLE				0x010
+#define BWMON_ENABLE_ENABLE			BIT(0)
+
+#define BWMON_V4_CLEAR				0x2a4
+#define BWMON_V5_CLEAR				0x014
+#define BWMON_CLEAR_CLEAR			BIT(0)
+#define BWMON_CLEAR_CLEAR_ALL			BIT(1)
+
+#define BWMON_V4_SAMPLE_WINDOW			0x2a8
+#define BWMON_V5_SAMPLE_WINDOW			0x020
+
+#define BWMON_V4_THRESHOLD_HIGH			0x2ac
+#define BWMON_V4_THRESHOLD_MED			0x2b0
+#define BWMON_V4_THRESHOLD_LOW			0x2b4
+#define BWMON_V5_THRESHOLD_HIGH			0x024
+#define BWMON_V5_THRESHOLD_MED			0x028
+#define BWMON_V5_THRESHOLD_LOW			0x02c
+
+#define BWMON_V4_ZONE_ACTIONS			0x2b8
+#define BWMON_V5_ZONE_ACTIONS			0x030
+/*
+ * Actions to perform on some zone 'z' when current zone hits the threshold:
+ * Increment counter of zone 'z'
+ */
+#define BWMON_ZONE_ACTIONS_INCREMENT(z)		(0x2 << ((z) * 2))
+/* Clear counter of zone 'z' */
+#define BWMON_ZONE_ACTIONS_CLEAR(z)		(0x1 << ((z) * 2))
+
+/* Zone 0 threshold hit: Clear zone count */
+#define BWMON_ZONE_ACTIONS_ZONE0		(BWMON_ZONE_ACTIONS_CLEAR(0))
+
+/* Zone 1 threshold hit: Increment zone count & clear lower zones */
+#define BWMON_ZONE_ACTIONS_ZONE1		(BWMON_ZONE_ACTIONS_INCREMENT(1) | \
+						 BWMON_ZONE_ACTIONS_CLEAR(0))
+
+/* Zone 2 threshold hit: Increment zone count & clear lower zones */
+#define BWMON_ZONE_ACTIONS_ZONE2		(BWMON_ZONE_ACTIONS_INCREMENT(2) | \
+						 BWMON_ZONE_ACTIONS_CLEAR(1) | \
+						 BWMON_ZONE_ACTIONS_CLEAR(0))
+
+/* Zone 3 threshold hit: Increment zone count & clear lower zones */
+#define BWMON_ZONE_ACTIONS_ZONE3		(BWMON_ZONE_ACTIONS_INCREMENT(3) | \
+						 BWMON_ZONE_ACTIONS_CLEAR(2) | \
+						 BWMON_ZONE_ACTIONS_CLEAR(1) | \
+						 BWMON_ZONE_ACTIONS_CLEAR(0))
+
+/*
+ * There is no clear documentation/explanation of BWMON_V4_THRESHOLD_COUNT
+ * register. Based on observations, this is number of times one threshold has to
+ * be reached, to trigger interrupt in given zone.
+ *
+ * 0xff are maximum values meant to ignore the zones 0 and 2.
+ */
+#define BWMON_V4_THRESHOLD_COUNT		0x2bc
+#define BWMON_V5_THRESHOLD_COUNT		0x034
+#define BWMON_THRESHOLD_COUNT_ZONE0_DEFAULT	0xff
+#define BWMON_THRESHOLD_COUNT_ZONE2_DEFAULT	0xff
+
+#define BWMON_V4_ZONE_MAX(zone)			(0x2e0 + 4 * (zone))
+#define BWMON_V5_ZONE_MAX(zone)			(0x044 + 4 * (zone))
+
+/* Quirks for specific BWMON types */
+#define BWMON_HAS_GLOBAL_IRQ			BIT(0)
+#define BWMON_NEEDS_FORCE_CLEAR			BIT(1)
+
+enum bwmon_fields {
+	F_GLOBAL_IRQ_CLEAR,
+	F_GLOBAL_IRQ_ENABLE,
+	F_IRQ_STATUS,
+	F_IRQ_CLEAR,
+	F_IRQ_ENABLE,
+	F_ENABLE,
+	F_CLEAR,
+	F_SAMPLE_WINDOW,
+	F_THRESHOLD_HIGH,
+	F_THRESHOLD_MED,
+	F_THRESHOLD_LOW,
+	F_ZONE_ACTIONS_ZONE0,
+	F_ZONE_ACTIONS_ZONE1,
+	F_ZONE_ACTIONS_ZONE2,
+	F_ZONE_ACTIONS_ZONE3,
+	F_THRESHOLD_COUNT_ZONE0,
+	F_THRESHOLD_COUNT_ZONE1,
+	F_THRESHOLD_COUNT_ZONE2,
+	F_THRESHOLD_COUNT_ZONE3,
+	F_ZONE0_MAX,
+	F_ZONE1_MAX,
+	F_ZONE2_MAX,
+	F_ZONE3_MAX,
+
+	F_NUM_FIELDS
+};
+
+struct icc_bwmon_data {
+	unsigned int sample_ms;
+	unsigned int count_unit_kb; /* kbytes */
+	unsigned int default_highbw_kbps;
+	unsigned int default_medbw_kbps;
+	unsigned int default_lowbw_kbps;
+	u8 zone1_thres_count;
+	u8 zone3_thres_count;
+	unsigned int quirks;
+
+	const struct regmap_config *regmap_cfg;
+	const struct reg_field *regmap_fields;
+};
+
+struct icc_bwmon {
+	struct device *dev;
+	const struct icc_bwmon_data *data;
+	int irq;
+
+	struct regmap *regmap;
+	struct regmap_field *regs[F_NUM_FIELDS];
+
+	unsigned int max_bw_kbps;
+	unsigned int min_bw_kbps;
+	unsigned int target_kbps;
+	unsigned int current_kbps;
+};
+
+/* BWMON v4 */
+static const struct reg_field msm8998_bwmon_reg_fields[] = {
+	[F_GLOBAL_IRQ_CLEAR]	= REG_FIELD(BWMON_V4_GLOBAL_IRQ_CLEAR, 0, 0),
+	[F_GLOBAL_IRQ_ENABLE]	= REG_FIELD(BWMON_V4_GLOBAL_IRQ_ENABLE, 0, 0),
+	[F_IRQ_STATUS]		= REG_FIELD(BWMON_V4_IRQ_STATUS, 4, 7),
+	[F_IRQ_CLEAR]		= REG_FIELD(BWMON_V4_IRQ_CLEAR, 4, 7),
+	[F_IRQ_ENABLE]		= REG_FIELD(BWMON_V4_IRQ_ENABLE, 4, 7),
+	/* F_ENABLE covers entire register to disable other features */
+	[F_ENABLE]		= REG_FIELD(BWMON_V4_ENABLE, 0, 31),
+	[F_CLEAR]		= REG_FIELD(BWMON_V4_CLEAR, 0, 1),
+	[F_SAMPLE_WINDOW]	= REG_FIELD(BWMON_V4_SAMPLE_WINDOW, 0, 23),
+	[F_THRESHOLD_HIGH]	= REG_FIELD(BWMON_V4_THRESHOLD_HIGH, 0, 11),
+	[F_THRESHOLD_MED]	= REG_FIELD(BWMON_V4_THRESHOLD_MED, 0, 11),
+	[F_THRESHOLD_LOW]	= REG_FIELD(BWMON_V4_THRESHOLD_LOW, 0, 11),
+	[F_ZONE_ACTIONS_ZONE0]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 0, 7),
+	[F_ZONE_ACTIONS_ZONE1]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 8, 15),
+	[F_ZONE_ACTIONS_ZONE2]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 16, 23),
+	[F_ZONE_ACTIONS_ZONE3]	= REG_FIELD(BWMON_V4_ZONE_ACTIONS, 24, 31),
+	[F_THRESHOLD_COUNT_ZONE0]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 0, 7),
+	[F_THRESHOLD_COUNT_ZONE1]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 8, 15),
+	[F_THRESHOLD_COUNT_ZONE2]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 16, 23),
+	[F_THRESHOLD_COUNT_ZONE3]	= REG_FIELD(BWMON_V4_THRESHOLD_COUNT, 24, 31),
+	[F_ZONE0_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(0), 0, 11),
+	[F_ZONE1_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(1), 0, 11),
+	[F_ZONE2_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(2), 0, 11),
+	[F_ZONE3_MAX]		= REG_FIELD(BWMON_V4_ZONE_MAX(3), 0, 11),
+};
+
+static const struct regmap_range msm8998_bwmon_reg_noread_ranges[] = {
+	regmap_reg_range(BWMON_V4_GLOBAL_IRQ_CLEAR, BWMON_V4_GLOBAL_IRQ_CLEAR),
+	regmap_reg_range(BWMON_V4_IRQ_CLEAR, BWMON_V4_IRQ_CLEAR),
+	regmap_reg_range(BWMON_V4_CLEAR, BWMON_V4_CLEAR),
+};
+
+static const struct regmap_access_table msm8998_bwmon_reg_read_table = {
+	.no_ranges	= msm8998_bwmon_reg_noread_ranges,
+	.n_no_ranges	= ARRAY_SIZE(msm8998_bwmon_reg_noread_ranges),
+};
+
+static const struct regmap_range msm8998_bwmon_reg_volatile_ranges[] = {
+	regmap_reg_range(BWMON_V4_IRQ_STATUS, BWMON_V4_IRQ_STATUS),
+	regmap_reg_range(BWMON_V4_ZONE_MAX(0), BWMON_V4_ZONE_MAX(3)),
+};
+
+static const struct regmap_access_table msm8998_bwmon_reg_volatile_table = {
+	.yes_ranges	= msm8998_bwmon_reg_volatile_ranges,
+	.n_yes_ranges	= ARRAY_SIZE(msm8998_bwmon_reg_volatile_ranges),
+};
+
+/*
+ * Fill the cache for non-readable registers only as rest does not really
+ * matter and can be read from the device.
+ */
+static const struct reg_default msm8998_bwmon_reg_defaults[] = {
+	{ BWMON_V4_GLOBAL_IRQ_CLEAR, 0x0 },
+	{ BWMON_V4_IRQ_CLEAR, 0x0 },
+	{ BWMON_V4_CLEAR, 0x0 },
+};
+
+static const struct regmap_config msm8998_bwmon_regmap_cfg = {
+	.reg_bits		= 32,
+	.reg_stride		= 4,
+	.val_bits		= 32,
+	/*
+	 * No concurrent access expected - driver has one interrupt handler,
+	 * regmap is not shared, no driver or user-space API.
+	 */
+	.disable_locking	= true,
+	.rd_table		= &msm8998_bwmon_reg_read_table,
+	.volatile_table		= &msm8998_bwmon_reg_volatile_table,
+	.reg_defaults		= msm8998_bwmon_reg_defaults,
+	.num_reg_defaults	= ARRAY_SIZE(msm8998_bwmon_reg_defaults),
+	/*
+	 * Cache is necessary for using regmap fields with non-readable
+	 * registers.
+	 */
+	.cache_type		= REGCACHE_RBTREE,
+};
+
+/* BWMON v5 */
+static const struct reg_field sdm845_llcc_bwmon_reg_fields[] = {
+	[F_GLOBAL_IRQ_CLEAR]	= {},
+	[F_GLOBAL_IRQ_ENABLE]	= {},
+	[F_IRQ_STATUS]		= REG_FIELD(BWMON_V5_IRQ_STATUS, 0, 3),
+	[F_IRQ_CLEAR]		= REG_FIELD(BWMON_V5_IRQ_CLEAR, 0, 3),
+	[F_IRQ_ENABLE]		= REG_FIELD(BWMON_V5_IRQ_ENABLE, 0, 3),
+	/* F_ENABLE covers entire register to disable other features */
+	[F_ENABLE]		= REG_FIELD(BWMON_V5_ENABLE, 0, 31),
+	[F_CLEAR]		= REG_FIELD(BWMON_V5_CLEAR, 0, 1),
+	[F_SAMPLE_WINDOW]	= REG_FIELD(BWMON_V5_SAMPLE_WINDOW, 0, 19),
+	[F_THRESHOLD_HIGH]	= REG_FIELD(BWMON_V5_THRESHOLD_HIGH, 0, 11),
+	[F_THRESHOLD_MED]	= REG_FIELD(BWMON_V5_THRESHOLD_MED, 0, 11),
+	[F_THRESHOLD_LOW]	= REG_FIELD(BWMON_V5_THRESHOLD_LOW, 0, 11),
+	[F_ZONE_ACTIONS_ZONE0]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 0, 7),
+	[F_ZONE_ACTIONS_ZONE1]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 8, 15),
+	[F_ZONE_ACTIONS_ZONE2]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 16, 23),
+	[F_ZONE_ACTIONS_ZONE3]	= REG_FIELD(BWMON_V5_ZONE_ACTIONS, 24, 31),
+	[F_THRESHOLD_COUNT_ZONE0]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 0, 7),
+	[F_THRESHOLD_COUNT_ZONE1]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 8, 15),
+	[F_THRESHOLD_COUNT_ZONE2]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 16, 23),
+	[F_THRESHOLD_COUNT_ZONE3]	= REG_FIELD(BWMON_V5_THRESHOLD_COUNT, 24, 31),
+	[F_ZONE0_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(0), 0, 11),
+	[F_ZONE1_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(1), 0, 11),
+	[F_ZONE2_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(2), 0, 11),
+	[F_ZONE3_MAX]		= REG_FIELD(BWMON_V5_ZONE_MAX(3), 0, 11),
+};
+
+static const struct regmap_range sdm845_llcc_bwmon_reg_noread_ranges[] = {
+	regmap_reg_range(BWMON_V5_IRQ_CLEAR, BWMON_V5_IRQ_CLEAR),
+	regmap_reg_range(BWMON_V5_CLEAR, BWMON_V5_CLEAR),
+};
+
+static const struct regmap_access_table sdm845_llcc_bwmon_reg_read_table = {
+	.no_ranges	= sdm845_llcc_bwmon_reg_noread_ranges,
+	.n_no_ranges	= ARRAY_SIZE(sdm845_llcc_bwmon_reg_noread_ranges),
+};
+
+static const struct regmap_range sdm845_llcc_bwmon_reg_volatile_ranges[] = {
+	regmap_reg_range(BWMON_V5_IRQ_STATUS, BWMON_V5_IRQ_STATUS),
+	regmap_reg_range(BWMON_V5_ZONE_MAX(0), BWMON_V5_ZONE_MAX(3)),
+};
+
+static const struct regmap_access_table sdm845_llcc_bwmon_reg_volatile_table = {
+	.yes_ranges	= sdm845_llcc_bwmon_reg_volatile_ranges,
+	.n_yes_ranges	= ARRAY_SIZE(sdm845_llcc_bwmon_reg_volatile_ranges),
+};
+
+/*
+ * Fill the cache for non-readable registers only as rest does not really
+ * matter and can be read from the device.
+ */
+static const struct reg_default sdm845_llcc_bwmon_reg_defaults[] = {
+	{ BWMON_V5_IRQ_CLEAR, 0x0 },
+	{ BWMON_V5_CLEAR, 0x0 },
+};
+
+static const struct regmap_config sdm845_llcc_bwmon_regmap_cfg = {
+	.reg_bits		= 32,
+	.reg_stride		= 4,
+	.val_bits		= 32,
+	/*
+	 * No concurrent access expected - driver has one interrupt handler,
+	 * regmap is not shared, no driver or user-space API.
+	 */
+	.disable_locking	= true,
+	.rd_table		= &sdm845_llcc_bwmon_reg_read_table,
+	.volatile_table		= &sdm845_llcc_bwmon_reg_volatile_table,
+	.reg_defaults		= sdm845_llcc_bwmon_reg_defaults,
+	.num_reg_defaults	= ARRAY_SIZE(sdm845_llcc_bwmon_reg_defaults),
+	/*
+	 * Cache is necessary for using regmap fields with non-readable
+	 * registers.
+	 */
+	.cache_type		= REGCACHE_RBTREE,
+};
+
+static void bwmon_clear_counters(struct icc_bwmon *bwmon, bool clear_all)
+{
+	unsigned int val = BWMON_CLEAR_CLEAR;
+
+	if (clear_all)
+		val |= BWMON_CLEAR_CLEAR_ALL;
+	/*
+	 * Clear counters. The order and barriers are
+	 * important. Quoting downstream Qualcomm msm-4.9 tree:
+	 *
+	 * The counter clear and IRQ clear bits are not in the same 4KB
+	 * region. So, we need to make sure the counter clear is completed
+	 * before we try to clear the IRQ or do any other counter operations.
+	 */
+	regmap_field_force_write(bwmon->regs[F_CLEAR], val);
+	if (bwmon->data->quirks & BWMON_NEEDS_FORCE_CLEAR)
+		regmap_field_force_write(bwmon->regs[F_CLEAR], 0);
+}
+
+static void bwmon_clear_irq(struct icc_bwmon *bwmon)
+{
+	/*
+	 * Clear zone and global interrupts. The order and barriers are
+	 * important. Quoting downstream Qualcomm msm-4.9 tree:
+	 *
+	 * Synchronize the local interrupt clear in mon_irq_clear()
+	 * with the global interrupt clear here. Otherwise, the CPU
+	 * may reorder the two writes and clear the global interrupt
+	 * before the local interrupt, causing the global interrupt
+	 * to be retriggered by the local interrupt still being high.
+	 *
+	 * Similarly, because the global registers are in a different
+	 * region than the local registers, we need to ensure any register
+	 * writes to enable the monitor after this call are ordered with the
+	 * clearing here so that local writes don't happen before the
+	 * interrupt is cleared.
+	 */
+	regmap_field_force_write(bwmon->regs[F_IRQ_CLEAR], BWMON_IRQ_ENABLE_MASK);
+	if (bwmon->data->quirks & BWMON_NEEDS_FORCE_CLEAR)
+		regmap_field_force_write(bwmon->regs[F_IRQ_CLEAR], 0);
+	if (bwmon->data->quirks & BWMON_HAS_GLOBAL_IRQ)
+		regmap_field_force_write(bwmon->regs[F_GLOBAL_IRQ_CLEAR],
+					 BWMON_V4_GLOBAL_IRQ_ENABLE_ENABLE);
+}
+
+static void bwmon_disable(struct icc_bwmon *bwmon)
+{
+	/* Disable interrupts. Strict ordering, see bwmon_clear_irq(). */
+	if (bwmon->data->quirks & BWMON_HAS_GLOBAL_IRQ)
+		regmap_field_write(bwmon->regs[F_GLOBAL_IRQ_ENABLE], 0x0);
+	regmap_field_write(bwmon->regs[F_IRQ_ENABLE], 0x0);
+
+	/*
+	 * Disable bwmon. Must happen before bwmon_clear_irq() to avoid spurious
+	 * IRQ.
+	 */
+	regmap_field_write(bwmon->regs[F_ENABLE], 0x0);
+}
+
+static void bwmon_enable(struct icc_bwmon *bwmon, unsigned int irq_enable)
+{
+	/* Enable interrupts */
+	if (bwmon->data->quirks & BWMON_HAS_GLOBAL_IRQ)
+		regmap_field_write(bwmon->regs[F_GLOBAL_IRQ_ENABLE],
+				   BWMON_V4_GLOBAL_IRQ_ENABLE_ENABLE);
+	regmap_field_write(bwmon->regs[F_IRQ_ENABLE], irq_enable);
+
+	/* Enable bwmon */
+	regmap_field_write(bwmon->regs[F_ENABLE], BWMON_ENABLE_ENABLE);
+}
+
+static unsigned int bwmon_kbps_to_count(struct icc_bwmon *bwmon,
+					unsigned int kbps)
+{
+	return kbps / bwmon->data->count_unit_kb;
+}
+
+static void bwmon_set_threshold(struct icc_bwmon *bwmon,
+				struct regmap_field *reg, unsigned int kbps)
+{
+	unsigned int thres;
+
+	thres = mult_frac(bwmon_kbps_to_count(bwmon, kbps),
+			  bwmon->data->sample_ms, MSEC_PER_SEC);
+	regmap_field_write(reg, thres);
+}
+
+static void bwmon_start(struct icc_bwmon *bwmon)
+{
+	const struct icc_bwmon_data *data = bwmon->data;
+	int window;
+
+	bwmon_clear_counters(bwmon, true);
+
+	window = mult_frac(bwmon->data->sample_ms, HW_TIMER_HZ, MSEC_PER_SEC);
+	/* Maximum sampling window: 0xffffff for v4 and 0xfffff for v5 */
+	regmap_field_write(bwmon->regs[F_SAMPLE_WINDOW], window);
+
+	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_HIGH],
+			    data->default_highbw_kbps);
+	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_MED],
+			    data->default_medbw_kbps);
+	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_LOW],
+			    data->default_lowbw_kbps);
+
+	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE0],
+			   BWMON_THRESHOLD_COUNT_ZONE0_DEFAULT);
+	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE1],
+			   data->zone1_thres_count);
+	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE2],
+			   BWMON_THRESHOLD_COUNT_ZONE2_DEFAULT);
+	regmap_field_write(bwmon->regs[F_THRESHOLD_COUNT_ZONE3],
+			   data->zone3_thres_count);
+
+	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE0],
+			   BWMON_ZONE_ACTIONS_ZONE0);
+	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE1],
+			   BWMON_ZONE_ACTIONS_ZONE1);
+	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE2],
+			   BWMON_ZONE_ACTIONS_ZONE2);
+	regmap_field_write(bwmon->regs[F_ZONE_ACTIONS_ZONE3],
+			   BWMON_ZONE_ACTIONS_ZONE3);
+
+	bwmon_clear_irq(bwmon);
+	bwmon_enable(bwmon, BWMON_IRQ_ENABLE_MASK);
+}
+
+static irqreturn_t bwmon_intr(int irq, void *dev_id)
+{
+	struct icc_bwmon *bwmon = dev_id;
+	unsigned int status, max;
+	int zone;
+
+	if (regmap_field_read(bwmon->regs[F_IRQ_STATUS], &status))
+		return IRQ_NONE;
+
+	status &= BWMON_IRQ_ENABLE_MASK;
+	if (!status) {
+		/*
+		 * Only zone 1 and zone 3 interrupts are enabled but zone 2
+		 * threshold could be hit and trigger interrupt even if not
+		 * enabled.
+		 * Such spurious interrupt might come with valuable max count or
+		 * not, so solution would be to always check all
+		 * BWMON_ZONE_MAX() registers to find the highest value.
+		 * Such case is currently ignored.
+		 */
+		return IRQ_NONE;
+	}
+
+	bwmon_disable(bwmon);
+
+	zone = get_bitmask_order(status) - 1;
+	/*
+	 * Zone max bytes count register returns count units within sampling
+	 * window.  Downstream kernel for BWMONv4 (called BWMON type 2 in
+	 * downstream) always increments the max bytes count by one.
+	 */
+	if (regmap_field_read(bwmon->regs[F_ZONE0_MAX + zone], &max))
+		return IRQ_NONE;
+
+	max += 1;
+	max *= bwmon->data->count_unit_kb;
+	bwmon->target_kbps = mult_frac(max, MSEC_PER_SEC, bwmon->data->sample_ms);
+
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t bwmon_intr_thread(int irq, void *dev_id)
+{
+	struct icc_bwmon *bwmon = dev_id;
+	unsigned int irq_enable = 0;
+	struct dev_pm_opp *opp, *target_opp;
+	unsigned int bw_kbps, up_kbps, down_kbps;
+
+	bw_kbps = bwmon->target_kbps;
+
+	target_opp = dev_pm_opp_find_bw_ceil(bwmon->dev, &bw_kbps, 0);
+	if (IS_ERR(target_opp) && PTR_ERR(target_opp) == -ERANGE)
+		target_opp = dev_pm_opp_find_bw_floor(bwmon->dev, &bw_kbps, 0);
+
+	bwmon->target_kbps = bw_kbps;
+
+	bw_kbps--;
+	opp = dev_pm_opp_find_bw_floor(bwmon->dev, &bw_kbps, 0);
+	if (IS_ERR(opp) && PTR_ERR(opp) == -ERANGE)
+		down_kbps = bwmon->target_kbps;
+	else
+		down_kbps = bw_kbps;
+
+	up_kbps = bwmon->target_kbps + 1;
+
+	if (bwmon->target_kbps >= bwmon->max_bw_kbps)
+		irq_enable = BIT(1);
+	else if (bwmon->target_kbps <= bwmon->min_bw_kbps)
+		irq_enable = BIT(3);
+	else
+		irq_enable = BWMON_IRQ_ENABLE_MASK;
+
+	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_HIGH],
+			    up_kbps);
+	bwmon_set_threshold(bwmon, bwmon->regs[F_THRESHOLD_MED],
+			    down_kbps);
+	bwmon_clear_counters(bwmon, false);
+	bwmon_clear_irq(bwmon);
+	bwmon_enable(bwmon, irq_enable);
+
+	if (bwmon->target_kbps == bwmon->current_kbps)
+		goto out;
+
+	dev_pm_opp_set_opp(bwmon->dev, target_opp);
+	bwmon->current_kbps = bwmon->target_kbps;
+
+out:
+	dev_pm_opp_put(target_opp);
+	if (!IS_ERR(opp))
+		dev_pm_opp_put(opp);
+
+	return IRQ_HANDLED;
+}
+
+static int bwmon_init_regmap(struct platform_device *pdev,
+			     struct icc_bwmon *bwmon)
+{
+	struct device *dev = &pdev->dev;
+	void __iomem *base;
+	struct regmap *map;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return dev_err_probe(dev, PTR_ERR(base),
+				     "failed to map bwmon registers\n");
+
+	map = devm_regmap_init_mmio(dev, base, bwmon->data->regmap_cfg);
+	if (IS_ERR(map))
+		return dev_err_probe(dev, PTR_ERR(map),
+				     "failed to initialize regmap\n");
+
+	BUILD_BUG_ON(ARRAY_SIZE(msm8998_bwmon_reg_fields) != F_NUM_FIELDS);
+	BUILD_BUG_ON(ARRAY_SIZE(sdm845_llcc_bwmon_reg_fields) != F_NUM_FIELDS);
+
+	return devm_regmap_field_bulk_alloc(dev, map, bwmon->regs,
+					   bwmon->data->regmap_fields,
+					   F_NUM_FIELDS);
+}
+
+static int bwmon_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct dev_pm_opp *opp;
+	struct icc_bwmon *bwmon;
+	int ret;
+
+	bwmon = devm_kzalloc(dev, sizeof(*bwmon), GFP_KERNEL);
+	if (!bwmon)
+		return -ENOMEM;
+
+	bwmon->data = of_device_get_match_data(dev);
+
+	ret = bwmon_init_regmap(pdev, bwmon);
+	if (ret)
+		return ret;
+
+	bwmon->irq = platform_get_irq(pdev, 0);
+	if (bwmon->irq < 0)
+		return bwmon->irq;
+
+	ret = devm_pm_opp_of_add_table(dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to add OPP table\n");
+
+	bwmon->max_bw_kbps = UINT_MAX;
+	opp = dev_pm_opp_find_bw_floor(dev, &bwmon->max_bw_kbps, 0);
+	if (IS_ERR(opp))
+		return dev_err_probe(dev, PTR_ERR(opp), "failed to find max peak bandwidth\n");
+
+	bwmon->min_bw_kbps = 0;
+	opp = dev_pm_opp_find_bw_ceil(dev, &bwmon->min_bw_kbps, 0);
+	if (IS_ERR(opp))
+		return dev_err_probe(dev, PTR_ERR(opp), "failed to find min peak bandwidth\n");
+
+	bwmon->dev = dev;
+
+	bwmon_disable(bwmon);
+	ret = devm_request_threaded_irq(dev, bwmon->irq, bwmon_intr,
+					bwmon_intr_thread,
+					IRQF_ONESHOT, dev_name(dev), bwmon);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to request IRQ\n");
+
+	platform_set_drvdata(pdev, bwmon);
+	bwmon_start(bwmon);
+
+	return 0;
+}
+
+static int bwmon_remove(struct platform_device *pdev)
+{
+	struct icc_bwmon *bwmon = platform_get_drvdata(pdev);
+
+	bwmon_disable(bwmon);
+
+	return 0;
+}
+
+static const struct icc_bwmon_data msm8998_bwmon_data = {
+	.sample_ms = 4,
+	.count_unit_kb = 64,
+	.default_highbw_kbps = 4800 * 1024, /* 4.8 GBps */
+	.default_medbw_kbps = 512 * 1024, /* 512 MBps */
+	.default_lowbw_kbps = 0,
+	.zone1_thres_count = 16,
+	.zone3_thres_count = 1,
+	.quirks = BWMON_HAS_GLOBAL_IRQ,
+	.regmap_fields = msm8998_bwmon_reg_fields,
+	.regmap_cfg = &msm8998_bwmon_regmap_cfg,
+};
+
+static const struct icc_bwmon_data sdm845_llcc_bwmon_data = {
+	.sample_ms = 4,
+	.count_unit_kb = 1024,
+	.default_highbw_kbps = 800 * 1024, /* 800 MBps */
+	.default_medbw_kbps = 256 * 1024, /* 256 MBps */
+	.default_lowbw_kbps = 0,
+	.zone1_thres_count = 16,
+	.zone3_thres_count = 1,
+	.regmap_fields = sdm845_llcc_bwmon_reg_fields,
+	.regmap_cfg = &sdm845_llcc_bwmon_regmap_cfg,
+};
+
+static const struct icc_bwmon_data sc7280_llcc_bwmon_data = {
+	.sample_ms = 4,
+	.count_unit_kb = 64,
+	.default_highbw_kbps = 800 * 1024, /* 800 MBps */
+	.default_medbw_kbps = 256 * 1024, /* 256 MBps */
+	.default_lowbw_kbps = 0,
+	.zone1_thres_count = 16,
+	.zone3_thres_count = 1,
+	.quirks = BWMON_NEEDS_FORCE_CLEAR,
+	.regmap_fields = sdm845_llcc_bwmon_reg_fields,
+	.regmap_cfg = &sdm845_llcc_bwmon_regmap_cfg,
+};
+
+static const struct of_device_id bwmon_of_match[] = {
+	{
+		.compatible = "qcom,msm8998-bwmon",
+		.data = &msm8998_bwmon_data
+	}, {
+		.compatible = "qcom,sdm845-llcc-bwmon",
+		.data = &sdm845_llcc_bwmon_data
+	}, {
+		.compatible = "qcom,sc7280-llcc-bwmon",
+		.data = &sc7280_llcc_bwmon_data
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, bwmon_of_match);
+
+static struct platform_driver bwmon_driver = {
+	.probe = bwmon_probe,
+	.remove = bwmon_remove,
+	.driver = {
+		.name = "qcom-bwmon",
+		.of_match_table = bwmon_of_match,
+	},
+};
+module_platform_driver(bwmon_driver);
+
+MODULE_AUTHOR("Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>");
+MODULE_DESCRIPTION("QCOM BWMON driver");
+MODULE_LICENSE("GPL");