[PATCH v3 6/7] soc: qcom: Add RPMh Power domain driver

[Rajendra Nayak]

The RPMh Power domain driver aggregates the corner votes from various
consumers for the ARC resources and communicates it to RPMh.

We also add data for all power domains on sdm845 SoC as part of the patch.
The driver can be extended to support other SoCs which support RPMh

Signed-off-by: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx>
---
 drivers/soc/qcom/Kconfig                |   9 +
 drivers/soc/qcom/Makefile               |   1 +
 drivers/soc/qcom/rpmhpd.c               | 427 ++++++++++++++++++++++++
 include/dt-bindings/power/qcom-rpmhpd.h |  31 ++
 4 files changed, 468 insertions(+)
 create mode 100644 drivers/soc/qcom/rpmhpd.c
 create mode 100644 include/dt-bindings/power/qcom-rpmhpd.h

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index 5c54931a7b99..7cb7eba2b997 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -74,6 +74,15 @@ config QCOM_RMTFS_MEM
 
 	  Say y here if you intend to boot the modem remoteproc.
 
+config QCOM_RPMHPD
+	tristate "Qualcomm RPMh Power domain driver"
+	depends on QCOM_RPMH && QCOM_COMMAND_DB
+	help
+	  QCOM RPMh Power domain driver to support power-domains with
+	  performance states. The driver communicates a performance state
+	  value to RPMh which then translates it into corresponding voltage
+	  for the voltage rail.
+
 config QCOM_RPMPD
 	tristate "Qualcomm RPM Power domain driver"
 	depends on MFD_QCOM_RPM && QCOM_SMD_RPM
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 9550c170de93..499513f63bef 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -16,3 +16,4 @@ obj-$(CONFIG_QCOM_SMSM)	+= smsm.o
 obj-$(CONFIG_QCOM_WCNSS_CTRL) += wcnss_ctrl.o
 obj-$(CONFIG_QCOM_APR) += apr.o
 obj-$(CONFIG_QCOM_RPMPD) += rpmpd.o
+obj-$(CONFIG_QCOM_RPMHPD) += rpmhpd.o
diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c
new file mode 100644
index 000000000000..7083ec1590ff
--- /dev/null
+++ b/drivers/soc/qcom/rpmhpd.c
@@ -0,0 +1,427 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2018, The Linux Foundation. All rights reserved.*/
+
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/pm_domain.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <soc/qcom/cmd-db.h>
+#include <soc/qcom/rpmh.h>
+#include <dt-bindings/power/qcom-rpmhpd.h>
+
+#define domain_to_rpmhpd(domain) container_of(domain, struct rpmhpd, pd)
+
+#define DEFINE_RPMHPD_AO(_platform, _name, _active)			\
+	static struct rpmhpd _platform##_##_active;			\
+	static struct rpmhpd _platform##_##_name = {			\
+		.pd = {	.name = #_name,	},				\
+		.peer = &_platform##_##_active,				\
+		.res_name = #_name".lvl",				\
+		.valid_state_mask = (BIT(RPMH_ACTIVE_ONLY_STATE) |	\
+					BIT(RPMH_WAKE_ONLY_STATE) |	\
+					BIT(RPMH_SLEEP_STATE)),		\
+	};								\
+	static struct rpmhpd _platform##_##_active = {			\
+		.pd = { .name = #_active, },				\
+		.peer = &_platform##_##_name,				\
+		.active_only = true,					\
+		.res_name = #_name".lvl",				\
+		.valid_state_mask = (BIT(RPMH_ACTIVE_ONLY_STATE) |	\
+					BIT(RPMH_WAKE_ONLY_STATE) |	\
+					BIT(RPMH_SLEEP_STATE)),		\
+	}
+
+#define DEFINE_RPMHPD(_platform, _name)					\
+	static struct rpmhpd _platform##_##_name = {			\
+		.pd = { .name = #_name, },				\
+		.res_name = #_name".lvl",				\
+		.valid_state_mask = BIT(RPMH_ACTIVE_ONLY_STATE),	\
+	}
+
+/*
+ * This is the number of bytes used for each command DB aux data entry of an
+ * ARC resource.
+ */
+#define RPMH_ARC_LEVEL_SIZE	2
+#define RPMH_ARC_MAX_LEVELS	16
+
+struct rpmhpd {
+	struct device	*dev;
+	struct generic_pm_domain pd;
+	struct rpmhpd	*peer;
+	const bool	active_only;
+	unsigned int	corner;
+	unsigned int	active_corner;
+	u32		level[RPMH_ARC_MAX_LEVELS];
+	int		level_count;
+	bool		enabled;
+	const char	*res_name;
+	u32		addr;
+	u8		valid_state_mask;
+};
+
+struct rpmhpd_desc {
+	struct rpmhpd **rpmhpds;
+	size_t num_pds;
+};
+
+static DEFINE_MUTEX(rpmhpd_lock);
+
+/* sdm845 RPMh Power domains */
+DEFINE_RPMHPD(sdm845, ebi);
+DEFINE_RPMHPD_AO(sdm845, mx, mx_ao);
+DEFINE_RPMHPD_AO(sdm845, cx, cx_ao);
+DEFINE_RPMHPD(sdm845, lmx);
+DEFINE_RPMHPD(sdm845, lcx);
+DEFINE_RPMHPD(sdm845, gfx);
+DEFINE_RPMHPD(sdm845, mss);
+
+static struct rpmhpd *sdm845_rpmhpds[] = {
+	[SDM845_EBI] = &sdm845_ebi,
+	[SDM845_MX] = &sdm845_mx,
+	[SDM845_MX_AO] = &sdm845_mx_ao,
+	[SDM845_CX] = &sdm845_cx,
+	[SDM845_CX_AO] = &sdm845_cx_ao,
+	[SDM845_LMX] = &sdm845_lmx,
+	[SDM845_LCX] = &sdm845_lcx,
+	[SDM845_GFX] = &sdm845_gfx,
+	[SDM845_MSS] = &sdm845_mss,
+};
+
+static const struct rpmhpd_desc sdm845_desc = {
+	.rpmhpds = sdm845_rpmhpds,
+	.num_pds = ARRAY_SIZE(sdm845_rpmhpds),
+};
+
+static const struct of_device_id rpmhpd_match_table[] = {
+	{ .compatible = "qcom,sdm845-rpmhpd", .data = &sdm845_desc },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, rpmhpd_match_table);
+
+static int rpmhpd_send_corner(struct rpmhpd *pd, int state,
+			      unsigned int corner, bool sync)
+{
+	struct tcs_cmd cmd = {
+		.addr = pd->addr,
+		.data = corner,
+	};
+
+	if (sync)
+		return rpmh_write(pd->dev, state, &cmd, 1);
+	else
+		return rpmh_write_async(pd->dev, state, &cmd, 1);
+}
+
+static int rpmhpd_send_corner_sync(struct rpmhpd *pd, int state,
+				   unsigned int corner)
+{
+	return rpmhpd_send_corner(pd, state, corner, true);
+}
+
+static int rpmhpd_send_corner_async(struct rpmhpd *pd, int state,
+				    unsigned int corner)
+{
+	return rpmhpd_send_corner(pd, state, corner, false);
+};
+
+static void to_active_sleep(struct rpmhpd *pd, unsigned int corner,
+			    unsigned int *active, unsigned int *sleep)
+{
+	*active = corner;
+
+	if (pd->active_only)
+		*sleep = 0;
+	else
+		*sleep = *active;
+}
+
+/*
+ * This function is used to aggregate the votes across the active only
+ * resources and its peers. The aggregated votes are send to RPMh as
+ * ACTIVE_ONLY votes (which take effect immediately), as WAKE_ONLY votes
+ * (applied by RPMh on system wakeup) and as SLEEP votes (applied by RPMh
+ * on system sleep).
+ * We send ACTIVE_ONLY votes for resources without any peers. For others,
+ * which have an active only peer, all 3 Votes are sent.
+ */
+static int rpmhpd_aggregate_corner(struct rpmhpd *pd, unsigned int corner)
+{
+	int ret = -EINVAL;
+	struct rpmhpd *peer = pd->peer;
+	unsigned int active_corner, sleep_corner;
+	unsigned int this_active_corner = 0, this_sleep_corner = 0;
+	unsigned int peer_active_corner = 0, peer_sleep_corner = 0;
+
+	to_active_sleep(pd, corner, &this_active_corner, &this_sleep_corner);
+
+	if (peer && peer->enabled)
+		to_active_sleep(peer, peer->corner, &peer_active_corner,
+				&peer_sleep_corner);
+
+	active_corner = max(this_active_corner, peer_active_corner);
+
+	if (pd->valid_state_mask & BIT(RPMH_ACTIVE_ONLY_STATE)) {
+		/*
+		 * Wait for an ack only when we are increasing the
+		 * perf state of the power domain
+		 */
+		if (active_corner > pd->active_corner)
+			ret = rpmhpd_send_corner_sync(pd,
+						      RPMH_ACTIVE_ONLY_STATE,
+						      active_corner);
+		else
+			ret = rpmhpd_send_corner_async(pd,
+						       RPMH_ACTIVE_ONLY_STATE,
+						       active_corner);
+		if (ret)
+			return ret;
+		pd->active_corner = active_corner;
+		if (peer)
+			peer->active_corner = active_corner;
+	}
+
+	if (pd->valid_state_mask & BIT(RPMH_WAKE_ONLY_STATE)) {
+		ret = rpmhpd_send_corner_async(pd, RPMH_WAKE_ONLY_STATE,
+					       active_corner);
+		if (ret)
+			return ret;
+	}
+
+	sleep_corner = max(this_sleep_corner, peer_sleep_corner);
+
+	if (pd->valid_state_mask & BIT(RPMH_SLEEP_STATE))
+		ret = rpmhpd_send_corner_async(pd, RPMH_SLEEP_STATE,
+					       sleep_corner);
+
+	return ret;
+}
+
+static int rpmhpd_power_on(struct generic_pm_domain *domain)
+{
+	struct rpmhpd *pd = domain_to_rpmhpd(domain);
+	int ret = 0;
+
+	mutex_lock(&rpmhpd_lock);
+
+	pd->enabled = true;
+
+	if (pd->corner)
+		ret = rpmhpd_aggregate_corner(pd, pd->corner);
+
+	mutex_unlock(&rpmhpd_lock);
+
+	return ret;
+}
+
+static int rpmhpd_power_off(struct generic_pm_domain *domain)
+{
+	struct rpmhpd *pd = domain_to_rpmhpd(domain);
+	int ret = 0;
+
+	mutex_lock(&rpmhpd_lock);
+
+	if (pd->level[0] == 0)
+		ret = rpmhpd_aggregate_corner(pd, 0);
+
+	if (!ret)
+		pd->enabled = false;
+
+	mutex_unlock(&rpmhpd_lock);
+
+	return ret;
+}
+
+static int rpmhpd_set_performance(struct generic_pm_domain *domain,
+				  unsigned int state)
+{
+	struct rpmhpd *pd = domain_to_rpmhpd(domain);
+	int ret = 0, i;
+
+	mutex_lock(&rpmhpd_lock);
+
+	for (i = 0; i < pd->level_count; i++)
+		if (state <= pd->level[i])
+			break;
+
+	if (i == pd->level_count) {
+		ret = -EINVAL;
+		dev_err(pd->dev, "invalid state=%u for domain %s",
+			state, pd->pd.name);
+			goto out;
+	}
+
+	pd->corner = i;
+
+	if (!pd->enabled)
+		goto out;
+
+	ret = rpmhpd_aggregate_corner(pd, i);
+out:
+	mutex_unlock(&rpmhpd_lock);
+
+	return ret;
+}
+
+static unsigned int rpmhpd_get_performance(struct generic_pm_domain *genpd,
+					   struct dev_pm_opp *opp)
+{
+	struct device_node *np;
+	unsigned int corner = 0;
+
+	np = dev_pm_opp_get_of_node(opp);
+	if (of_property_read_u32(np, "qcom,level", &corner)) {
+		pr_err("%s: missing 'qcom,level' property\n", __func__);
+		return 0;
+	}
+
+	of_node_put(np);
+
+	return corner;
+}
+
+static int rpmhpd_update_level_mapping(struct rpmhpd *rpmhpd)
+{
+	int i, j, len, ret;
+	u8 buf[RPMH_ARC_MAX_LEVELS * RPMH_ARC_LEVEL_SIZE];
+
+	len = cmd_db_read_aux_data_len(rpmhpd->res_name);
+	if (len <= 0)
+		return len;
+
+	if (len > RPMH_ARC_MAX_LEVELS * RPMH_ARC_LEVEL_SIZE)
+		return -EINVAL;
+
+	ret = cmd_db_read_aux_data(rpmhpd->res_name, buf, len);
+	if (ret < 0)
+		return ret;
+
+	rpmhpd->level_count = len / RPMH_ARC_LEVEL_SIZE;
+
+	for (i = 0; i < rpmhpd->level_count; i++) {
+		rpmhpd->level[i] = 0;
+		for (j = 0; j < RPMH_ARC_LEVEL_SIZE; j++)
+			rpmhpd->level[i] |=
+				buf[i * RPMH_ARC_LEVEL_SIZE + j] << (8 * j);
+
+		/*
+		 * The AUX data may be zero padded.  These 0 valued entries at
+		 * the end of the map must be ignored.
+		 */
+		if (i > 0 && rpmhpd->level[i] == 0) {
+			rpmhpd->level_count = i;
+			break;
+		}
+		pr_dbg("%s: ARC hlvl=%2d --> vlvl=%4u\n", rpmhpd->res_name, i,
+		       rpmhpd->level[i]);
+	}
+
+	return 0;
+}
+
+static int rpmhpd_probe(struct platform_device *pdev)
+{
+	int i, ret;
+	size_t num;
+	struct genpd_onecell_data *data;
+	struct rpmhpd **rpmhpds;
+	const struct rpmhpd_desc *desc;
+
+	desc = of_device_get_match_data(&pdev->dev);
+	if (!desc)
+		return -EINVAL;
+
+	rpmhpds = desc->rpmhpds;
+	num = desc->num_pds;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->domains = devm_kcalloc(&pdev->dev, num, sizeof(*data->domains),
+				     GFP_KERNEL);
+	data->num_domains = num;
+
+	ret = cmd_db_ready();
+	if (ret) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Command DB unavailable, ret=%d\n",
+				ret);
+		return ret;
+	}
+
+	for (i = 0; i < num; i++) {
+		if (!rpmhpds[i]) {
+			dev_warn(&pdev->dev, "rpmhpds[] with empty entry at index=%d\n",
+				 i);
+			continue;
+		}
+
+		rpmhpds[i]->dev = &pdev->dev;
+		rpmhpds[i]->addr = cmd_db_read_addr(rpmhpds[i]->res_name);
+		if (!rpmhpds[i]->addr) {
+			dev_err(&pdev->dev, "Could not find RPMh address for resource %s\n",
+				rpmhpds[i]->res_name);
+			return -ENODEV;
+		}
+
+		ret = cmd_db_read_slave_id(rpmhpds[i]->res_name);
+		if (ret != CMD_DB_HW_ARC) {
+			dev_err(&pdev->dev, "RPMh slave ID mismatch\n");
+			return -EINVAL;
+		}
+
+		ret = rpmhpd_update_level_mapping(rpmhpds[i]);
+		if (ret)
+			return ret;
+
+		rpmhpds[i]->pd.power_off = rpmhpd_power_off;
+		rpmhpds[i]->pd.power_on = rpmhpd_power_on;
+		rpmhpds[i]->pd.set_performance_state = rpmhpd_set_performance;
+		rpmhpds[i]->pd.opp_to_performance_state = rpmhpd_get_performance;
+		pm_genpd_init(&rpmhpds[i]->pd, NULL, true);
+
+		data->domains[i] = &rpmhpds[i]->pd;
+	}
+
+	return of_genpd_add_provider_onecell(pdev->dev.of_node, data);
+}
+
+static int rpmhpd_remove(struct platform_device *pdev)
+{
+	of_genpd_del_provider(pdev->dev.of_node);
+	return 0;
+}
+
+static struct platform_driver rpmhpd_driver = {
+	.driver = {
+		.name = "qcom-rpmhpd",
+		.of_match_table = rpmhpd_match_table,
+	},
+	.probe = rpmhpd_probe,
+	.remove = rpmhpd_remove,
+};
+
+static int __init rpmhpd_init(void)
+{
+	return platform_driver_register(&rpmhpd_driver);
+}
+core_initcall(rpmhpd_init);
+
+static void __exit rpmhpd_exit(void)
+{
+	platform_driver_unregister(&rpmhpd_driver);
+}
+module_exit(rpmhpd_exit);
+
+MODULE_DESCRIPTION("Qualcomm Technologies, Inc. RPMh Power Domain Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:qcom-rpmhpd");
diff --git a/include/dt-bindings/power/qcom-rpmhpd.h b/include/dt-bindings/power/qcom-rpmhpd.h
new file mode 100644
index 000000000000..b01ae2452603
--- /dev/null
+++ b/include/dt-bindings/power/qcom-rpmhpd.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2018, The Linux Foundation. All rights reserved. */
+
+#ifndef _DT_BINDINGS_POWER_QCOM_RPMHPD_H
+#define _DT_BINDINGS_POWER_QCOM_RPMHPD_H
+
+/* SDM845 Power Domain Indexes */
+#define SDM845_EBI	0
+#define SDM845_MX	1
+#define SDM845_MX_AO	2
+#define SDM845_CX	3
+#define SDM845_CX_AO	4
+#define SDM845_LMX	5
+#define SDM845_LCX	6
+#define SDM845_GFX	7
+#define SDM845_MSS	8
+
+/* SDM845 Power Domain performance levels */
+#define RPMH_REGULATOR_LEVEL_OFF	0
+#define RPMH_REGULATOR_LEVEL_RETENTION	16
+#define RPMH_REGULATOR_LEVEL_MIN_SVS	48
+#define RPMH_REGULATOR_LEVEL_LOW_SVS	64
+#define RPMH_REGULATOR_LEVEL_SVS	128
+#define RPMH_REGULATOR_LEVEL_SVS_L1	192
+#define RPMH_REGULATOR_LEVEL_NOM	256
+#define RPMH_REGULATOR_LEVEL_NOM_L1	320
+#define RPMH_REGULATOR_LEVEL_NOM_L2	336
+#define RPMH_REGULATOR_LEVEL_TURBO	384
+#define RPMH_REGULATOR_LEVEL_TURBO_L1	416
+
+#endif
-- 
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