Thread (3 messages) 3 messages, 3 authors, 2016-02-10
STALE3772d

[PATCH V5 11/14] soc: tegra: pmc: Add generic PM domain support

From: jonathanh@nvidia.com (Jon Hunter)
Date: 2016-01-28 16:33:49
Also in: linux-devicetree, linux-pm, linux-tegra
Subsystem: open firmware and flattened device tree bindings, the rest · Maintainers: Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds

Possibly related (same subject, not in this thread)

Adds generic PM support to the PMC driver where the PM domains are
populated from device-tree and the PM domain consumer devices are
bound to their relevant PM domains via device-tree as well.

Update the tegra_powergate_sequence_power_up() API so that internally
it calls the same tegra_powergate_xxx functions that are used by the
tegra generic power domain code for consistency.

This is based upon work by Thierry Reding [off-list ref]
and Vince Hsu [off-list ref].

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
---
 drivers/soc/tegra/pmc.c                     | 470 ++++++++++++++++++++++++++--
 include/dt-bindings/power/tegra-powergate.h |  36 +++
 include/soc/tegra/pmc.h                     |  39 +--
 3 files changed, 480 insertions(+), 65 deletions(-)
 create mode 100644 include/dt-bindings/power/tegra-powergate.h
diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
index ecb4f66819fd..915dc37e0d92 100644
--- a/drivers/soc/tegra/pmc.c
+++ b/drivers/soc/tegra/pmc.c
@@ -19,6 +19,8 @@
 
 #define pr_fmt(fmt) "tegra-pmc: " fmt
 
+#include <dt-bindings/power/tegra-powergate.h>
+
 #include <linux/kernel.h>
 #include <linux/clk.h>
 #include <linux/clk/tegra.h>
@@ -31,7 +33,9 @@
 #include <linux/iopoll.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
+#include <linux/pm_domain.h>
 #include <linux/reboot.h>
 #include <linux/reset.h>
 #include <linux/seq_file.h>
@@ -102,6 +106,19 @@
 
 #define GPU_RG_CNTRL			0x2d4
 
+struct tegra_powergate {
+	struct generic_pm_domain genpd;
+	struct generic_pm_domain *parent;
+	struct tegra_pmc *pmc;
+	unsigned int id;
+	struct list_head node;
+	struct device_node *of_node;
+	struct clk **clks;
+	unsigned int num_clks;
+	struct reset_control **resets;
+	unsigned int num_resets;
+};
+
 struct tegra_pmc_soc {
 	unsigned int num_powergates;
 	const char *const *powergates;
@@ -134,6 +151,7 @@ struct tegra_pmc_soc {
  * @lp0_vec_phys: physical base address of the LP0 warm boot code
  * @lp0_vec_size: size of the LP0 warm boot code
  * @powergates_valid: Bitmap of valid power gates
+ * @powergates_list: list of power gates
  * @powergates_lock: mutex for power gate register access
  */
 struct tegra_pmc {
@@ -160,6 +178,7 @@ struct tegra_pmc {
 	u32 lp0_vec_size;
 	DECLARE_BITMAP(powergates_valid, TEGRA_POWERGATE_MAX);
 
+	struct list_head powergates_list;
 	struct mutex powergates_lock;
 };
 
@@ -168,6 +187,12 @@ static struct tegra_pmc *pmc = &(struct tegra_pmc) {
 	.suspend_mode = TEGRA_SUSPEND_NONE,
 };
 
+static inline struct tegra_powergate *
+to_powergate(struct generic_pm_domain *domain)
+{
+	return container_of(domain, struct tegra_powergate, genpd);
+}
+
 static u32 tegra_pmc_readl(unsigned long offset)
 {
 	return readl(pmc->base + offset);
@@ -218,6 +243,174 @@ static int tegra_powergate_set(unsigned int id, bool new_state)
 	return err;
 }
 
+static void tegra_powergate_disable_clocks(struct tegra_powergate *pg)
+{
+	unsigned int i;
+
+	for (i = 0; i < pg->num_clks; i++)
+		clk_disable_unprepare(pg->clks[i]);
+}
+
+static int tegra_powergate_enable_clocks(struct tegra_powergate *pg)
+{
+	unsigned int i;
+	int err;
+
+	for (i = 0; i < pg->num_clks; i++) {
+		err = clk_prepare_enable(pg->clks[i]);
+		if (err)
+			goto out;
+	}
+
+	return 0;
+
+out:
+	while (i--)
+		clk_disable_unprepare(pg->clks[i]);
+
+	return err;
+}
+
+static int tegra_powergate_reset_assert(struct tegra_powergate *pg)
+{
+	unsigned int i;
+	int err;
+
+	for (i = 0; i < pg->num_resets; i++) {
+		err = reset_control_assert(pg->resets[i]);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int tegra_powergate_reset_deassert(struct tegra_powergate *pg)
+{
+	unsigned int i;
+	int err;
+
+	for (i = 0; i < pg->num_resets; i++) {
+		err = reset_control_deassert(pg->resets[i]);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int tegra_powergate_power_up(struct tegra_powergate *pg,
+				    bool disable_clocks)
+{
+	int err;
+
+	err = tegra_powergate_reset_assert(pg);
+	if (err)
+		return err;
+
+	usleep_range(10, 20);
+
+	err = tegra_powergate_set(pg->id, true);
+	if (err < 0)
+		return err;
+
+	usleep_range(10, 20);
+
+	err = tegra_powergate_enable_clocks(pg);
+	if (err)
+		goto err_clks;
+
+	usleep_range(10, 20);
+
+	tegra_powergate_remove_clamping(pg->id);
+
+	usleep_range(10, 20);
+
+	err = tegra_powergate_reset_deassert(pg);
+	if (err)
+		goto err_reset;
+
+	usleep_range(10, 20);
+
+	if (disable_clocks)
+		tegra_powergate_disable_clocks(pg);
+
+	return 0;
+
+err_reset:
+	tegra_powergate_disable_clocks(pg);
+	usleep_range(10, 20);
+err_clks:
+	tegra_powergate_set(pg->id, false);
+
+	return err;
+}
+
+static int tegra_powergate_power_down(struct tegra_powergate *pg)
+{
+	int err;
+
+	err = tegra_powergate_enable_clocks(pg);
+	if (err)
+		return err;
+
+	usleep_range(10, 20);
+
+	err = tegra_powergate_reset_assert(pg);
+	if (err)
+		goto err_reset;
+
+	usleep_range(10, 20);
+
+	tegra_powergate_disable_clocks(pg);
+
+	usleep_range(10, 20);
+
+	err = tegra_powergate_set(pg->id, false);
+	if (err)
+		goto err_powergate;
+
+	return 0;
+
+err_powergate:
+	tegra_powergate_enable_clocks(pg);
+	usleep_range(10, 20);
+	tegra_powergate_reset_deassert(pg);
+	usleep_range(10, 20);
+err_reset:
+	tegra_powergate_disable_clocks(pg);
+
+	return err;
+}
+
+static int tegra_genpd_power_on(struct generic_pm_domain *domain)
+{
+	struct tegra_powergate *pg = to_powergate(domain);
+	struct tegra_pmc *pmc = pg->pmc;
+	int err;
+
+	err = tegra_powergate_power_up(pg, true);
+	if (err)
+		dev_err(pmc->dev, "failed to turn on PM domain %s: %d\n",
+			pg->of_node->name, err);
+
+	return err;
+}
+
+static int tegra_genpd_power_off(struct generic_pm_domain *domain)
+{
+	struct tegra_powergate *pg = to_powergate(domain);
+	struct tegra_pmc *pmc = pg->pmc;
+	int err;
+
+	err = tegra_powergate_power_down(pg);
+	if (err)
+		dev_err(pmc->dev, "failed to turn off PM domain %s: %d\n",
+			pg->of_node->name, err);
+
+	return err;
+}
+
 /**
  * tegra_powergate_power_on() - power on partition
  * @id: partition ID
@@ -319,35 +512,20 @@ EXPORT_SYMBOL(tegra_powergate_remove_clamping);
 int tegra_powergate_sequence_power_up(unsigned int id, struct clk *clk,
 				      struct reset_control *rst)
 {
-	int ret;
-
-	reset_control_assert(rst);
-
-	ret = tegra_powergate_power_on(id);
-	if (ret)
-		goto err_power;
-
-	ret = clk_prepare_enable(clk);
-	if (ret)
-		goto err_clk;
-
-	usleep_range(10, 20);
+	struct tegra_powergate pg;
+	int err;
 
-	ret = tegra_powergate_remove_clamping(id);
-	if (ret)
-		goto err_clamp;
+	pg.id = id;
+	pg.clks = &clk;
+	pg.num_clks = 1;
+	pg.resets = &rst;
+	pg.num_resets = 1;
 
-	usleep_range(10, 20);
-	reset_control_deassert(rst);
+	err = tegra_powergate_power_up(&pg, false);
+	if (err)
+		pr_err("failed to turn on partition %d: %d\n", id, err);
 
-	return 0;
-
-err_clamp:
-	clk_disable_unprepare(clk);
-err_clk:
-	tegra_powergate_power_off(id);
-err_power:
-	return ret;
+	return err;
 }
 EXPORT_SYMBOL(tegra_powergate_sequence_power_up);
 
@@ -487,6 +665,233 @@ static int tegra_powergate_debugfs_init(void)
 	return 0;
 }
 
+static int tegra_powergate_of_get_clks(struct device *dev,
+				       struct tegra_powergate *pg)
+{
+	struct clk *clk;
+	unsigned int i;
+	int err;
+
+	pg->num_clks = of_count_phandle_with_args(pg->of_node, "clocks",
+						  "#clock-cells");
+	if (pg->num_clks == 0)
+		return -ENODEV;
+
+	pg->clks = devm_kcalloc(dev, pg->num_clks, sizeof(clk), GFP_KERNEL);
+	if (!pg->clks)
+		return -ENOMEM;
+
+	for (i = 0; i < pg->num_clks; i++) {
+		pg->clks[i] = of_clk_get(pg->of_node, i);
+		if (IS_ERR(pg->clks[i])) {
+			err = PTR_ERR(pg->clks[i]);
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	while (i--)
+		clk_put(pg->clks[i]);
+
+	pg->num_clks = 0;
+
+	return err;
+}
+
+static int tegra_powergate_of_get_resets(struct device *dev,
+					 struct tegra_powergate *pg)
+{
+	struct reset_control *rst;
+	unsigned int i;
+	int err;
+
+	pg->num_resets = of_count_phandle_with_args(pg->of_node, "resets",
+					   "#reset-cells");
+	if (pg->num_resets == 0)
+		return -ENODEV;
+
+	pg->resets = devm_kcalloc(dev, pg->num_resets, sizeof(rst), GFP_KERNEL);
+	if (!pg->resets)
+		return -ENOMEM;
+
+	for (i = 0; i < pg->num_resets; i++) {
+		pg->resets[i] = of_reset_control_get_by_index(pg->of_node, i);
+		if (IS_ERR(pg->resets[i])) {
+			err = PTR_ERR(pg->resets[i]);
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	while (i--)
+		reset_control_put(pg->resets[i]);
+
+	pg->num_resets = 0;
+
+	return err;
+}
+
+static struct tegra_powergate *
+tegra_powergate_add_one(struct tegra_pmc *pmc, struct device_node *np,
+			struct generic_pm_domain *parent)
+{
+	struct tegra_powergate *pg;
+	unsigned int id;
+	bool off;
+	int err;
+
+	/*
+	 * If the powergate ID is missing or invalid then return NULL
+	 * to skip this one and allow any others to be created.
+	 */
+	err = of_property_read_u32(np, "nvidia,powergate", &id);
+	if (err) {
+		dev_WARN(pmc->dev, "no powergate ID for node %s\n", np->name);
+		return NULL;
+	}
+
+	if (!tegra_powergate_is_valid(id)) {
+		dev_WARN(pmc->dev, "powergate ID invalid for %s\n", np->name);
+		return NULL;
+	}
+
+	pg = devm_kzalloc(pmc->dev, sizeof(*pg), GFP_KERNEL);
+	if (!pg) {
+		err = -ENOMEM;
+		goto error;
+	}
+
+	pg->id = id;
+	pg->of_node = np;
+	pg->parent = parent;
+	pg->genpd.name = np->name;
+	pg->genpd.power_off = tegra_genpd_power_off;
+	pg->genpd.power_on = tegra_genpd_power_on;
+	pg->pmc = pmc;
+
+	err = tegra_powergate_of_get_clks(pmc->dev, pg);
+	if (err)
+		goto error;
+
+	err = tegra_powergate_of_get_resets(pmc->dev, pg);
+	if (err)
+		goto remove_clks;
+
+	off = !tegra_powergate_is_powered(pg->id);
+
+	pm_genpd_init(&pg->genpd, NULL, off);
+
+	if (pg->parent) {
+		err = pm_genpd_add_subdomain(pg->parent, &pg->genpd);
+		if (err)
+			goto remove_domain_and_resets;
+	}
+
+	err = of_genpd_add_provider_simple(pg->of_node, &pg->genpd);
+	if (err)
+		goto remove_subdomain;
+
+	list_add_tail(&pg->node, &pmc->powergates_list);
+
+	dev_dbg(pmc->dev, "added power domain %s\n", pg->genpd.name);
+
+	return pg;
+
+remove_subdomain:
+	WARN_ON(pm_genpd_remove_subdomain(pg->parent, &pg->genpd));
+remove_domain_and_resets:
+	WARN_ON(pm_genpd_remove(&pg->genpd));
+	while (pg->num_resets--)
+		reset_control_put(pg->resets[pg->num_resets]);
+remove_clks:
+	while (pg->num_clks--)
+		clk_put(pg->clks[pg->num_clks]);
+error:
+	dev_err(pmc->dev, "failed to create power domain for node %s\n",
+		np->name);
+
+	return ERR_PTR(err);
+}
+
+static int tegra_powergate_add(struct tegra_pmc *pmc, struct device_node *np,
+			       struct generic_pm_domain *parent)
+{
+	struct tegra_powergate *pg;
+	struct device_node *child;
+	int err = 0;
+
+	for_each_child_of_node(np, child) {
+		pg = tegra_powergate_add_one(pmc, child, parent);
+		if (IS_ERR(pg)) {
+			err = PTR_ERR(pg);
+			goto err;
+		}
+
+		if (pg)
+			err = tegra_powergate_add(pmc, child, pg->parent);
+
+err:
+		of_node_put(child);
+
+		if (err)
+			break;
+	}
+
+	return err;
+}
+
+static void tegra_powergate_remove(struct tegra_pmc *pmc)
+{
+	struct tegra_powergate *pg, *n;
+
+	list_for_each_entry_safe(pg, n, &pmc->powergates_list, node) {
+		of_genpd_del_provider(pg->of_node);
+
+		if (pg->parent) {
+			if (WARN_ON(pm_genpd_remove_subdomain(pg->parent,
+							      &pg->genpd)))
+				return;
+
+			pg->parent = NULL;
+		}
+
+		if (WARN_ON(pm_genpd_remove(&pg->genpd)))
+			return;
+
+		while (pg->num_clks--)
+			clk_put(pg->clks[pg->num_clks]);
+
+		while (pg->num_resets--)
+			reset_control_put(pg->resets[pg->num_resets]);
+
+		list_del(&pg->node);
+	}
+}
+
+static int tegra_powergate_init(struct tegra_pmc *pmc)
+{
+	struct device_node *np;
+	int err;
+
+	INIT_LIST_HEAD(&pmc->powergates_list);
+
+	np = of_get_child_by_name(pmc->dev->of_node, "powergates");
+	if (!np)
+		return 0;
+
+	err = tegra_powergate_add(pmc, np, NULL);
+	if (err)
+		tegra_powergate_remove(pmc);
+
+	of_node_put(np);
+
+	return err;
+}
+
 static int tegra_io_rail_prepare(unsigned int id, unsigned long *request,
 				 unsigned long *status, unsigned int *bit)
 {
@@ -880,24 +1285,31 @@ static int tegra_pmc_probe(struct platform_device *pdev)
 
 	tegra_pmc_init_tsense_reset(pmc);
 
+	err = tegra_powergate_init(pmc);
+	if (err < 0)
+		goto error;
+
 	if (IS_ENABLED(CONFIG_DEBUG_FS)) {
 		err = tegra_powergate_debugfs_init();
 		if (err < 0)
-			goto error;
+			goto remove_powergates;
 	}
 
 	err = register_restart_handler(&tegra_pmc_restart_handler);
 	if (err) {
-		debugfs_remove(pmc->debugfs);
 		dev_err(&pdev->dev, "unable to register restart handler, %d\n",
 			err);
-		goto error;
+		goto remove_debugfs;
 	}
 
 	iounmap(base);
 
 	return 0;
 
+remove_debugfs:
+	debugfs_remove(pmc->debugfs);
+remove_powergates:
+	tegra_powergate_remove(pmc);
 error:
 	mutex_lock(&pmc->powergates_lock);
 	pmc->base = base;
diff --git a/include/dt-bindings/power/tegra-powergate.h b/include/dt-bindings/power/tegra-powergate.h
new file mode 100644
index 000000000000..bcab501badfc
--- /dev/null
+++ b/include/dt-bindings/power/tegra-powergate.h
@@ -0,0 +1,36 @@
+#ifndef _DT_BINDINGS_POWER_TEGRA_POWERGATE_H
+#define _DT_BINDINGS_POWER_TEGRA_POWERGATE_H
+
+#define TEGRA_POWERGATE_CPU	0
+#define TEGRA_POWERGATE_3D	1
+#define TEGRA_POWERGATE_VENC	2
+#define TEGRA_POWERGATE_PCIE	3
+#define TEGRA_POWERGATE_VDEC	4
+#define TEGRA_POWERGATE_L2	5
+#define TEGRA_POWERGATE_MPE	6
+#define TEGRA_POWERGATE_HEG	7
+#define TEGRA_POWERGATE_SATA	8
+#define TEGRA_POWERGATE_CPU1	9
+#define TEGRA_POWERGATE_CPU2	10
+#define TEGRA_POWERGATE_CPU3	11
+#define TEGRA_POWERGATE_CELP	12
+#define TEGRA_POWERGATE_3D1	13
+#define TEGRA_POWERGATE_CPU0	14
+#define TEGRA_POWERGATE_C0NC	15
+#define TEGRA_POWERGATE_C1NC	16
+#define TEGRA_POWERGATE_SOR	17
+#define TEGRA_POWERGATE_DIS	18
+#define TEGRA_POWERGATE_DISB	19
+#define TEGRA_POWERGATE_XUSBA	20
+#define TEGRA_POWERGATE_XUSBB	21
+#define TEGRA_POWERGATE_XUSBC	22
+#define TEGRA_POWERGATE_VIC	23
+#define TEGRA_POWERGATE_IRAM	24
+#define TEGRA_POWERGATE_NVDEC	25
+#define TEGRA_POWERGATE_NVJPG	26
+#define TEGRA_POWERGATE_AUD	27
+#define TEGRA_POWERGATE_DFD	28
+#define TEGRA_POWERGATE_VE2	29
+#define TEGRA_POWERGATE_MAX	TEGRA_POWERGATE_VE2
+
+#endif
diff --git a/include/soc/tegra/pmc.h b/include/soc/tegra/pmc.h
index e9e53473a63e..c028557365ad 100644
--- a/include/soc/tegra/pmc.h
+++ b/include/soc/tegra/pmc.h
@@ -19,6 +19,8 @@
 #ifndef __SOC_TEGRA_PMC_H__
 #define __SOC_TEGRA_PMC_H__
 
+#include <dt-bindings/power/tegra-powergate.h>
+
 #include <linux/reboot.h>
 
 #include <soc/tegra/pm.h>
@@ -39,43 +41,8 @@ int tegra_pmc_cpu_remove_clamping(unsigned int cpuid);
 #endif /* CONFIG_SMP */
 
 /*
- * powergate and I/O rail APIs
+ * I/O rail APIs
  */
-
-#define TEGRA_POWERGATE_CPU	0
-#define TEGRA_POWERGATE_3D	1
-#define TEGRA_POWERGATE_VENC	2
-#define TEGRA_POWERGATE_PCIE	3
-#define TEGRA_POWERGATE_VDEC	4
-#define TEGRA_POWERGATE_L2	5
-#define TEGRA_POWERGATE_MPE	6
-#define TEGRA_POWERGATE_HEG	7
-#define TEGRA_POWERGATE_SATA	8
-#define TEGRA_POWERGATE_CPU1	9
-#define TEGRA_POWERGATE_CPU2	10
-#define TEGRA_POWERGATE_CPU3	11
-#define TEGRA_POWERGATE_CELP	12
-#define TEGRA_POWERGATE_3D1	13
-#define TEGRA_POWERGATE_CPU0	14
-#define TEGRA_POWERGATE_C0NC	15
-#define TEGRA_POWERGATE_C1NC	16
-#define TEGRA_POWERGATE_SOR	17
-#define TEGRA_POWERGATE_DIS	18
-#define TEGRA_POWERGATE_DISB	19
-#define TEGRA_POWERGATE_XUSBA	20
-#define TEGRA_POWERGATE_XUSBB	21
-#define TEGRA_POWERGATE_XUSBC	22
-#define TEGRA_POWERGATE_VIC	23
-#define TEGRA_POWERGATE_IRAM	24
-#define TEGRA_POWERGATE_NVDEC	25
-#define TEGRA_POWERGATE_NVJPG	26
-#define TEGRA_POWERGATE_AUD	27
-#define TEGRA_POWERGATE_DFD	28
-#define TEGRA_POWERGATE_VE2	29
-#define TEGRA_POWERGATE_MAX	TEGRA_POWERGATE_VE2
-
-#define TEGRA_POWERGATE_3D0	TEGRA_POWERGATE_3D
-
 #define TEGRA_IO_RAIL_CSIA	0
 #define TEGRA_IO_RAIL_CSIB	1
 #define TEGRA_IO_RAIL_DSI	2
-- 
2.1.4
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help