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Merge tag 'clk-renesas-for-v4.11-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers into clk-next

Pull Renesas clk driver updates from Geert Uytterhoeven:

  - Use CLK_IS_CRITICAL to handle critical clocks,
  - Add Reset Control Support for R-Car Gen2 and Gen3, and RZ/G1,
  - Add IIC-DVFS clocks for R-Car H3 and M3-W,
  - Minor cleanups.

* tag 'clk-renesas-for-v4.11-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers:
  clk: renesas: r8a7796: Add IIC-DVFS clock
  clk: renesas: r8a7795: Add IIC-DVFS clock
  clk: renesas: cpg-mssr: Add support for reset control
  clk: renesas: cpg-mssr: Rename cpg_mssr_priv.mstp_lock
  clk: renesas: cpg-mssr: Document suitability for RZ/G1
  dt-bindings: clock: renesas: cpg-mssr: Document reset control support
  clk: renesas: mstp: Reformat cpg_mstp_clock_register() for git diff
  clk: renesas: mstp: Make INTC-SYS a critical clock
  clk: renesas: cpg-mssr: Migrate to CLK_IS_CRITICAL
Stephen Boyd 8 years ago
parent
commit
d646d812f3

+ 6 - 0
Documentation/devicetree/bindings/clock/renesas,cpg-mssr.txt

@@ -42,6 +42,10 @@ Required Properties:
 	Domain bindings in
 	Documentation/devicetree/bindings/power/power_domain.txt.
 
+  - #reset-cells: Must be 1
+      - The single reset specifier cell must be the module number, as defined
+	in the datasheet.
+
 
 Examples
 --------
@@ -55,6 +59,7 @@ Examples
 		clock-names = "extal", "extalr";
 		#clock-cells = <2>;
 		#power-domain-cells = <0>;
+		#reset-cells = <1>;
 	};
 
 
@@ -69,5 +74,6 @@ Examples
 		dmas = <&dmac1 0x13>, <&dmac1 0x12>;
 		dma-names = "tx", "rx";
 		power-domains = <&cpg>;
+		resets = <&cpg 310>;
 		status = "disabled";
 	};

+ 8 - 3
drivers/clk/renesas/clk-mstp.c

@@ -141,9 +141,9 @@ static const struct clk_ops cpg_mstp_clock_ops = {
 	.is_enabled = cpg_mstp_clock_is_enabled,
 };
 
-static struct clk * __init
-cpg_mstp_clock_register(const char *name, const char *parent_name,
-			unsigned int index, struct mstp_clock_group *group)
+static struct clk * __init cpg_mstp_clock_register(const char *name,
+	const char *parent_name, unsigned int index,
+	struct mstp_clock_group *group)
 {
 	struct clk_init_data init;
 	struct mstp_clock *clock;
@@ -158,6 +158,11 @@ cpg_mstp_clock_register(const char *name, const char *parent_name,
 	init.name = name;
 	init.ops = &cpg_mstp_clock_ops;
 	init.flags = CLK_IS_BASIC | CLK_SET_RATE_PARENT;
+	/* INTC-SYS is the module clock of the GIC, and must not be disabled */
+	if (!strcmp(name, "intc-sys")) {
+		pr_debug("MSTP %s setting CLK_IS_CRITICAL\n", name);
+		init.flags |= CLK_IS_CRITICAL;
+	}
 	init.parent_names = &parent_name;
 	init.num_parents = 1;
 

+ 1 - 0
drivers/clk/renesas/r8a7795-cpg-mssr.c

@@ -221,6 +221,7 @@ static const struct mssr_mod_clk r8a7795_mod_clks[] __initconst = {
 	DEF_MOD("can-if0",		 916,	R8A7795_CLK_S3D4),
 	DEF_MOD("i2c6",			 918,	R8A7795_CLK_S3D2),
 	DEF_MOD("i2c5",			 919,	R8A7795_CLK_S3D2),
+	DEF_MOD("i2c-dvfs",		 926,	R8A7795_CLK_CP),
 	DEF_MOD("i2c4",			 927,	R8A7795_CLK_S3D2),
 	DEF_MOD("i2c3",			 928,	R8A7795_CLK_S3D2),
 	DEF_MOD("i2c2",			 929,	R8A7795_CLK_S3D2),

+ 1 - 0
drivers/clk/renesas/r8a7796-cpg-mssr.c

@@ -192,6 +192,7 @@ static const struct mssr_mod_clk r8a7796_mod_clks[] __initconst = {
 	DEF_MOD("can-if0",		 916,	R8A7796_CLK_S3D4),
 	DEF_MOD("i2c6",			 918,	R8A7796_CLK_S0D6),
 	DEF_MOD("i2c5",			 919,	R8A7796_CLK_S0D6),
+	DEF_MOD("i2c-dvfs",		 926,	R8A7796_CLK_CP),
 	DEF_MOD("i2c4",			 927,	R8A7796_CLK_S0D6),
 	DEF_MOD("i2c3",			 928,	R8A7796_CLK_S0D6),
 	DEF_MOD("i2c2",			 929,	R8A7796_CLK_S3D2),

+ 134 - 15
drivers/clk/renesas/renesas-cpg-mssr.c

@@ -16,6 +16,7 @@
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/clk/renesas.h>
+#include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/init.h>
 #include <linux/mod_devicetable.h>
@@ -25,6 +26,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_clock.h>
 #include <linux/pm_domain.h>
+#include <linux/reset-controller.h>
 #include <linux/slab.h>
 
 #include <dt-bindings/clock/renesas-cpg-mssr.h>
@@ -43,7 +45,7 @@
  * Module Standby and Software Reset register offets.
  *
  * If the registers exist, these are valid for SH-Mobile, R-Mobile,
- * R-Car Gen 2, and R-Car Gen 3.
+ * R-Car Gen2, R-Car Gen3, and RZ/G1.
  * These are NOT valid for R-Car Gen1 and RZ/A1!
  */
 
@@ -96,18 +98,22 @@ static const u16 srcr[] = {
 /**
  * Clock Pulse Generator / Module Standby and Software Reset Private Data
  *
+ * @rcdev: Optional reset controller entity
  * @dev: CPG/MSSR device
  * @base: CPG/MSSR register block base address
- * @mstp_lock: protects writes to SMSTPCR
+ * @rmw_lock: protects RMW register accesses
  * @clks: Array containing all Core and Module Clocks
  * @num_core_clks: Number of Core Clocks in clks[]
  * @num_mod_clks: Number of Module Clocks in clks[]
  * @last_dt_core_clk: ID of the last Core Clock exported to DT
  */
 struct cpg_mssr_priv {
+#ifdef CONFIG_RESET_CONTROLLER
+	struct reset_controller_dev rcdev;
+#endif
 	struct device *dev;
 	void __iomem *base;
-	spinlock_t mstp_lock;
+	spinlock_t rmw_lock;
 
 	struct clk **clks;
 	unsigned int num_core_clks;
@@ -144,7 +150,7 @@ static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
 
 	dev_dbg(dev, "MSTP %u%02u/%pC %s\n", reg, bit, hw->clk,
 		enable ? "ON" : "OFF");
-	spin_lock_irqsave(&priv->mstp_lock, flags);
+	spin_lock_irqsave(&priv->rmw_lock, flags);
 
 	value = readl(priv->base + SMSTPCR(reg));
 	if (enable)
@@ -153,7 +159,7 @@ static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable)
 		value |= bitmask;
 	writel(value, priv->base + SMSTPCR(reg));
 
-	spin_unlock_irqrestore(&priv->mstp_lock, flags);
+	spin_unlock_irqrestore(&priv->rmw_lock, flags);
 
 	if (!enable)
 		return 0;
@@ -346,17 +352,10 @@ static void __init cpg_mssr_register_mod_clk(const struct mssr_mod_clk *mod,
 	init.flags = CLK_IS_BASIC | CLK_SET_RATE_PARENT;
 	for (i = 0; i < info->num_crit_mod_clks; i++)
 		if (id == info->crit_mod_clks[i]) {
-#ifdef CLK_ENABLE_HAND_OFF
-			dev_dbg(dev, "MSTP %s setting CLK_ENABLE_HAND_OFF\n",
+			dev_dbg(dev, "MSTP %s setting CLK_IS_CRITICAL\n",
 				mod->name);
-			init.flags |= CLK_ENABLE_HAND_OFF;
+			init.flags |= CLK_IS_CRITICAL;
 			break;
-#else
-			dev_dbg(dev, "Ignoring MSTP %s to prevent disabling\n",
-				mod->name);
-			kfree(clock);
-			return;
-#endif
 		}
 
 	parent_name = __clk_get_name(parent);
@@ -501,6 +500,122 @@ static int __init cpg_mssr_add_clk_domain(struct device *dev,
 	return 0;
 }
 
+#ifdef CONFIG_RESET_CONTROLLER
+
+#define rcdev_to_priv(x)	container_of(x, struct cpg_mssr_priv, rcdev)
+
+static int cpg_mssr_reset(struct reset_controller_dev *rcdev,
+			  unsigned long id)
+{
+	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
+	unsigned int reg = id / 32;
+	unsigned int bit = id % 32;
+	u32 bitmask = BIT(bit);
+	unsigned long flags;
+	u32 value;
+
+	dev_dbg(priv->dev, "reset %u%02u\n", reg, bit);
+
+	/* Reset module */
+	spin_lock_irqsave(&priv->rmw_lock, flags);
+	value = readl(priv->base + SRCR(reg));
+	value |= bitmask;
+	writel(value, priv->base + SRCR(reg));
+	spin_unlock_irqrestore(&priv->rmw_lock, flags);
+
+	/* Wait for at least one cycle of the RCLK clock (@ ca. 32 kHz) */
+	udelay(35);
+
+	/* Release module from reset state */
+	writel(bitmask, priv->base + SRSTCLR(reg));
+
+	return 0;
+}
+
+static int cpg_mssr_assert(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
+	unsigned int reg = id / 32;
+	unsigned int bit = id % 32;
+	u32 bitmask = BIT(bit);
+	unsigned long flags;
+	u32 value;
+
+	dev_dbg(priv->dev, "assert %u%02u\n", reg, bit);
+
+	spin_lock_irqsave(&priv->rmw_lock, flags);
+	value = readl(priv->base + SRCR(reg));
+	value |= bitmask;
+	writel(value, priv->base + SRCR(reg));
+	spin_unlock_irqrestore(&priv->rmw_lock, flags);
+	return 0;
+}
+
+static int cpg_mssr_deassert(struct reset_controller_dev *rcdev,
+			     unsigned long id)
+{
+	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
+	unsigned int reg = id / 32;
+	unsigned int bit = id % 32;
+	u32 bitmask = BIT(bit);
+
+	dev_dbg(priv->dev, "deassert %u%02u\n", reg, bit);
+
+	writel(bitmask, priv->base + SRSTCLR(reg));
+	return 0;
+}
+
+static int cpg_mssr_status(struct reset_controller_dev *rcdev,
+			   unsigned long id)
+{
+	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
+	unsigned int reg = id / 32;
+	unsigned int bit = id % 32;
+	u32 bitmask = BIT(bit);
+
+	return !!(readl(priv->base + SRCR(reg)) & bitmask);
+}
+
+static const struct reset_control_ops cpg_mssr_reset_ops = {
+	.reset = cpg_mssr_reset,
+	.assert = cpg_mssr_assert,
+	.deassert = cpg_mssr_deassert,
+	.status = cpg_mssr_status,
+};
+
+static int cpg_mssr_reset_xlate(struct reset_controller_dev *rcdev,
+				const struct of_phandle_args *reset_spec)
+{
+	struct cpg_mssr_priv *priv = rcdev_to_priv(rcdev);
+	unsigned int unpacked = reset_spec->args[0];
+	unsigned int idx = MOD_CLK_PACK(unpacked);
+
+	if (unpacked % 100 > 31 || idx >= rcdev->nr_resets) {
+		dev_err(priv->dev, "Invalid reset index %u\n", unpacked);
+		return -EINVAL;
+	}
+
+	return idx;
+}
+
+static int cpg_mssr_reset_controller_register(struct cpg_mssr_priv *priv)
+{
+	priv->rcdev.ops = &cpg_mssr_reset_ops;
+	priv->rcdev.of_node = priv->dev->of_node;
+	priv->rcdev.of_reset_n_cells = 1;
+	priv->rcdev.of_xlate = cpg_mssr_reset_xlate;
+	priv->rcdev.nr_resets = priv->num_mod_clks;
+	return devm_reset_controller_register(priv->dev, &priv->rcdev);
+}
+
+#else /* !CONFIG_RESET_CONTROLLER */
+static inline int cpg_mssr_reset_controller_register(struct cpg_mssr_priv *priv)
+{
+	return 0;
+}
+#endif /* !CONFIG_RESET_CONTROLLER */
+
+
 static const struct of_device_id cpg_mssr_match[] = {
 #ifdef CONFIG_ARCH_R8A7743
 	{
@@ -557,7 +672,7 @@ static int __init cpg_mssr_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	priv->dev = dev;
-	spin_lock_init(&priv->mstp_lock);
+	spin_lock_init(&priv->rmw_lock);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	priv->base = devm_ioremap_resource(dev, res);
@@ -598,6 +713,10 @@ static int __init cpg_mssr_probe(struct platform_device *pdev)
 	if (error)
 		return error;
 
+	error = cpg_mssr_reset_controller_register(priv);
+	if (error)
+		return error;
+
 	return 0;
 }