Add generic PM domain support for Tegra

index 08966c26d65c..bb173456bbff 100644
@@ -31,10 +31,13 @@
 #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>
+#include <linux/slab.h>
 #include <linux/spinlock.h>
 
 #include <soc/tegra/common.h>

@@ -102,6 +105,16 @@
 
 #define GPU_RG_CNTRL			0x2d4
 
+struct tegra_powergate {
+	struct generic_pm_domain genpd;
+	struct tegra_pmc *pmc;
+	unsigned int id;
+	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;

@@ -132,6 +145,7 @@ struct tegra_pmc_soc {
  * @cpu_pwr_good_en: CPU power good signal is enabled
  * @lp0_vec_phys: physical base address of the LP0 warm boot code
  * @lp0_vec_size: size of the LP0 warm boot code
+ * @powergates_available: Bitmap of available power gates
  * @powergates_lock: mutex for power gate register access
  */
 struct tegra_pmc {

@@ -156,6 +170,7 @@ struct tegra_pmc {
 	bool cpu_pwr_good_en;
 	u32 lp0_vec_phys;
 	u32 lp0_vec_size;
+	DECLARE_BITMAP(powergates_available, TEGRA_POWERGATE_MAX);
 
 	struct mutex powergates_lock;
 };

@@ -165,6 +180,12 @@ 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);

@@ -188,6 +209,31 @@ static inline bool tegra_powergate_is_valid(int id)
 	return (pmc->soc && pmc->soc->powergates[id]);
 }
 
+static inline bool tegra_powergate_is_available(int id)
+{
+	return test_bit(id, pmc->powergates_available);
+}
+
+static int tegra_powergate_lookup(struct tegra_pmc *pmc, const char *name)
+{
+	unsigned int i;
+
+	if (!pmc || !pmc->soc || !name)
+		return -EINVAL;
+
+	for (i = 0; i < pmc->soc->num_powergates; i++) {
+		if (!tegra_powergate_is_valid(i))
+			continue;
+
+		if (!strcmp(name, pmc->soc->powergates[i]))
+			return i;
+	}
+
+	dev_err(pmc->dev, "powergate %s not found\n", name);
+
+	return -ENODEV;
+}
+
 /**
  * tegra_powergate_set() - set the state of a partition
  * @id: partition ID

@@ -218,13 +264,219 @@ static int tegra_powergate_set(unsigned int id, bool new_state)
 	return err;
 }
 
+static int __tegra_powergate_remove_clamping(unsigned int id)
+{
+	u32 mask;
+
+	mutex_lock(&pmc->powergates_lock);
+
+	/*
+	 * On Tegra124 and later, the clamps for the GPU are controlled by a
+	 * separate register (with different semantics).
+	 */
+	if (id == TEGRA_POWERGATE_3D) {
+		if (pmc->soc->has_gpu_clamps) {
+			tegra_pmc_writel(0, GPU_RG_CNTRL);
+			goto out;
+		}
+	}
+
+	/*
+	 * Tegra 2 has a bug where PCIE and VDE clamping masks are
+	 * swapped relatively to the partition ids
+	 */
+	if (id == TEGRA_POWERGATE_VDEC)
+		mask = (1 << TEGRA_POWERGATE_PCIE);
+	else if (id == TEGRA_POWERGATE_PCIE)
+		mask = (1 << TEGRA_POWERGATE_VDEC);
+	else
+		mask = (1 << id);
+
+	tegra_pmc_writel(mask, REMOVE_CLAMPING);
+
+out:
+	mutex_unlock(&pmc->powergates_lock);
+
+	return 0;
+}
+
+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 disable_clks;
+
+	usleep_range(10, 20);
+
+	err = __tegra_powergate_remove_clamping(pg->id);
+	if (err)
+		goto disable_clks;
+
+	usleep_range(10, 20);
+
+	err = tegra_powergate_reset_deassert(pg);
+	if (err)
+		goto powergate_off;
+
+	usleep_range(10, 20);
+
+	if (disable_clocks)
+		tegra_powergate_disable_clocks(pg);
+
+	return 0;
+
+disable_clks:
+	tegra_powergate_disable_clocks(pg);
+	usleep_range(10, 20);
+powergate_off:
+	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 disable_clks;
+
+	usleep_range(10, 20);
+
+	tegra_powergate_disable_clocks(pg);
+
+	usleep_range(10, 20);
+
+	err = tegra_powergate_set(pg->id, false);
+	if (err)
+		goto assert_resets;
+
+	return 0;
+
+assert_resets:
+	tegra_powergate_enable_clocks(pg);
+	usleep_range(10, 20);
+	tegra_powergate_reset_deassert(pg);
+	usleep_range(10, 20);
+disable_clks:
+	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->genpd.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->genpd.name, err);
+
+	return err;
+}
+
 /**
  * tegra_powergate_power_on() - power on partition
  * @id: partition ID
  */
 int tegra_powergate_power_on(unsigned int id)
 {
-	if (!tegra_powergate_is_valid(id))
+	if (!tegra_powergate_is_available(id))
 		return -EINVAL;
 
 	return tegra_powergate_set(id, true);

@@ -236,7 +488,7 @@ int tegra_powergate_power_on(unsigned int id)
  */
 int tegra_powergate_power_off(unsigned int id)
 {
-	if (!tegra_powergate_is_valid(id))
+	if (!tegra_powergate_is_available(id))
 		return -EINVAL;
 
 	return tegra_powergate_set(id, false);

@@ -267,41 +519,10 @@ int tegra_powergate_is_powered(unsigned int id)
  */
 int tegra_powergate_remove_clamping(unsigned int id)
 {
-	u32 mask;
-
-	if (!tegra_powergate_is_valid(id))
+	if (!tegra_powergate_is_available(id))
 		return -EINVAL;
 
-	mutex_lock(&pmc->powergates_lock);
-
-	/*
-	 * On Tegra124 and later, the clamps for the GPU are controlled by a
-	 * separate register (with different semantics).
-	 */
-	if (id == TEGRA_POWERGATE_3D) {
-		if (pmc->soc->has_gpu_clamps) {
-			tegra_pmc_writel(0, GPU_RG_CNTRL);
-			goto out;
-		}
-	}
-
-	/*
-	 * Tegra 2 has a bug where PCIE and VDE clamping masks are
-	 * swapped relatively to the partition ids
-	 */
-	if (id == TEGRA_POWERGATE_VDEC)
-		mask = (1 << TEGRA_POWERGATE_PCIE);
-	else if (id == TEGRA_POWERGATE_PCIE)
-		mask = (1 << TEGRA_POWERGATE_VDEC);
-	else
-		mask = (1 << id);
-
-	tegra_pmc_writel(mask, REMOVE_CLAMPING);
-
-out:
-	mutex_unlock(&pmc->powergates_lock);
-
-	return 0;
+	return __tegra_powergate_remove_clamping(id);
 }
 EXPORT_SYMBOL(tegra_powergate_remove_clamping);
 

@@ -316,35 +537,20 @@ 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);
-
-	return 0;
+	err = tegra_powergate_power_up(&pg, false);
+	if (err)
+		pr_err("failed to turn on partition %d: %d\n", id, err);
 
-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);
 

@@ -486,6 +692,155 @@ static int tegra_powergate_debugfs_init(void)
 	return 0;
 }
 
+static int tegra_powergate_of_get_clks(struct tegra_powergate *pg,
+				       struct device_node *np)
+{
+	struct clk *clk;
+	unsigned int i, count;
+	int err;
+
+	count = of_count_phandle_with_args(np, "clocks", "#clock-cells");
+	if (count == 0)
+		return -ENODEV;
+
+	pg->clks = kcalloc(count, sizeof(clk), GFP_KERNEL);
+	if (!pg->clks)
+		return -ENOMEM;
+
+	for (i = 0; i < count; i++) {
+		pg->clks[i] = of_clk_get(np, i);
+		if (IS_ERR(pg->clks[i])) {
+			err = PTR_ERR(pg->clks[i]);
+			goto err;
+		}
+	}
+
+	pg->num_clks = count;
+
+	return 0;
+
+err:
+	while (i--)
+		clk_put(pg->clks[i]);
+	kfree(pg->clks);
+
+	return err;
+}
+
+static int tegra_powergate_of_get_resets(struct tegra_powergate *pg,
+					 struct device_node *np)
+{
+	struct reset_control *rst;
+	unsigned int i, count;
+	int err;
+
+	count = of_count_phandle_with_args(np, "resets", "#reset-cells");
+	if (count == 0)
+		return -ENODEV;
+
+	pg->resets = kcalloc(count, sizeof(rst), GFP_KERNEL);
+	if (!pg->resets)
+		return -ENOMEM;
+
+	for (i = 0; i < count; i++) {
+		pg->resets[i] = of_reset_control_get_by_index(np, i);
+		if (IS_ERR(pg->resets[i])) {
+			err = PTR_ERR(pg->resets[i]);
+			goto error;
+		}
+	}
+
+	pg->num_resets = count;
+
+	return 0;
+
+error:
+	while (i--)
+		reset_control_put(pg->resets[i]);
+	kfree(pg->resets);
+
+	return err;
+}
+
+static void tegra_powergate_add(struct tegra_pmc *pmc, struct device_node *np)
+{
+	struct tegra_powergate *pg;
+	bool off;
+	int id;
+
+	pg = kzalloc(sizeof(*pg), GFP_KERNEL);
+	if (!pg)
+		goto error;
+
+	id = tegra_powergate_lookup(pmc, np->name);
+	if (id < 0)
+		goto free_mem;
+
+	/*
+	 * Clear the bit for this powergate so it cannot be managed
+	 * directly via the legacy APIs for controlling powergates.
+	 */
+	clear_bit(id, pmc->powergates_available);
+
+	pg->id = id;
+	pg->genpd.name = np->name;
+	pg->genpd.power_off = tegra_genpd_power_off;
+	pg->genpd.power_on = tegra_genpd_power_on;
+	pg->pmc = pmc;
+
+	if (tegra_powergate_of_get_clks(pg, np))
+		goto set_available;
+
+	if (tegra_powergate_of_get_resets(pg, np))
+		goto remove_clks;
+
+	off = !tegra_powergate_is_powered(pg->id);
+
+	pm_genpd_init(&pg->genpd, NULL, off);
+
+	if (of_genpd_add_provider_simple(np, &pg->genpd))
+		goto remove_resets;
+
+	dev_dbg(pmc->dev, "added power domain %s\n", pg->genpd.name);
+
+	return;
+
+remove_resets:
+	while (pg->num_resets--)
+		reset_control_put(pg->resets[pg->num_resets]);
+	kfree(pg->resets);
+
+remove_clks:
+	while (pg->num_clks--)
+		clk_put(pg->clks[pg->num_clks]);
+	kfree(pg->clks);
+
+set_available:
+	set_bit(id, pmc->powergates_available);
+
+free_mem:
+	kfree(pg);
+
+error:
+	dev_err(pmc->dev, "failed to create power domain for %s\n", np->name);
+}
+
+static void tegra_powergate_init(struct tegra_pmc *pmc)
+{
+	struct device_node *np, *child;
+
+	np = of_get_child_by_name(pmc->dev->of_node, "powergates");
+	if (!np)
+		return;
+
+	for_each_child_of_node(np, child) {
+		tegra_powergate_add(pmc, child);
+		of_node_put(child);
+	}
+
+	of_node_put(np);
+}
+
 static int tegra_io_rail_prepare(unsigned int id, unsigned long *request,
 				 unsigned long *status, unsigned int *bit)
 {

@@ -887,6 +1242,8 @@ static int tegra_pmc_probe(struct platform_device *pdev)
 		return err;
 	}
 
+	tegra_powergate_init(pmc);
+
 	mutex_lock(&pmc->powergates_lock);
 	iounmap(pmc->base);
 	pmc->base = base;

@@ -1120,6 +1477,7 @@ static int __init tegra_pmc_early_init(void)
 	const struct of_device_id *match;
 	struct device_node *np;
 	struct resource regs;
+	unsigned int i;
 	bool invert;
 	u32 value;
 

@@ -1169,6 +1527,11 @@ static int __init tegra_pmc_early_init(void)
 		return -ENXIO;
 	}
 
+	/* Create a bit-map of the available and valid partitions */
+	for (i = 0; i < pmc->soc->num_powergates; i++)
+		if (pmc->soc->powergates[i])
+			set_bit(i, pmc->powergates_available);
+
 	mutex_init(&pmc->powergates_lock);
 
 	/*

index 07e332dd44fb..e9e53473a63e 100644
@@ -72,6 +72,7 @@ int tegra_pmc_cpu_remove_clamping(unsigned int cpuid);
 #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