1 files changed, 315 insertions, 71 deletions

diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c
index 6843ec87b98b..9b89ff4881de 100644
--- a/drivers/char/hw_random/omap-rng.c
+++ b/drivers/char/hw_random/omap-rng.c
@@ -24,57 +24,131 @@
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/interrupt.h>
 
 #include <asm/io.h>
 
-#define RNG_OUT_REG		0x00		/* Output register */
-#define RNG_STAT_REG		0x04		/* Status register
-							[0] = STAT_BUSY */
-#define RNG_ALARM_REG		0x24		/* Alarm register
-							[7:0] = ALARM_COUNTER */
-#define RNG_CONFIG_REG		0x28		/* Configuration register
-							[11:6] = RESET_COUNT
-							[5:3]  = RING2_DELAY
-							[2:0]  = RING1_DELAY */
-#define RNG_REV_REG		0x3c		/* Revision register
-							[7:0] = REV_NB */
-#define RNG_MASK_REG		0x40		/* Mask and reset register
-							[2] = IT_EN
-							[1] = SOFTRESET
-							[0] = AUTOIDLE */
-#define RNG_SYSSTATUS		0x44		/* System status
-							[0] = RESETDONE */
+#define RNG_REG_STATUS_RDY			(1 << 0)
+
+#define RNG_REG_INTACK_RDY_MASK			(1 << 0)
+#define RNG_REG_INTACK_SHUTDOWN_OFLO_MASK	(1 << 1)
+#define RNG_SHUTDOWN_OFLO_MASK			(1 << 1)
+
+#define RNG_CONTROL_STARTUP_CYCLES_SHIFT	16
+#define RNG_CONTROL_STARTUP_CYCLES_MASK		(0xffff << 16)
+#define RNG_CONTROL_ENABLE_TRNG_SHIFT		10
+#define RNG_CONTROL_ENABLE_TRNG_MASK		(1 << 10)
+
+#define RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT	16
+#define RNG_CONFIG_MAX_REFIL_CYCLES_MASK	(0xffff << 16)
+#define RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT	0
+#define RNG_CONFIG_MIN_REFIL_CYCLES_MASK	(0xff << 0)
+
+#define RNG_CONTROL_STARTUP_CYCLES		0xff
+#define RNG_CONFIG_MIN_REFIL_CYCLES		0x21
+#define RNG_CONFIG_MAX_REFIL_CYCLES		0x22
+
+#define RNG_ALARMCNT_ALARM_TH_SHIFT		0x0
+#define RNG_ALARMCNT_ALARM_TH_MASK		(0xff << 0)
+#define RNG_ALARMCNT_SHUTDOWN_TH_SHIFT		16
+#define RNG_ALARMCNT_SHUTDOWN_TH_MASK		(0x1f << 16)
+#define RNG_ALARM_THRESHOLD			0xff
+#define RNG_SHUTDOWN_THRESHOLD			0x4
+
+#define RNG_REG_FROENABLE_MASK			0xffffff
+#define RNG_REG_FRODETUNE_MASK			0xffffff
+
+#define OMAP2_RNG_OUTPUT_SIZE			0x4
+#define OMAP4_RNG_OUTPUT_SIZE			0x8
+
+enum {
+	RNG_OUTPUT_L_REG = 0,
+	RNG_OUTPUT_H_REG,
+	RNG_STATUS_REG,
+	RNG_INTMASK_REG,
+	RNG_INTACK_REG,
+	RNG_CONTROL_REG,
+	RNG_CONFIG_REG,
+	RNG_ALARMCNT_REG,
+	RNG_FROENABLE_REG,
+	RNG_FRODETUNE_REG,
+	RNG_ALARMMASK_REG,
+	RNG_ALARMSTOP_REG,
+	RNG_REV_REG,
+	RNG_SYSCONFIG_REG,
+};
+
+static const u16 reg_map_omap2[] = {
+	[RNG_OUTPUT_L_REG]	= 0x0,
+	[RNG_STATUS_REG]	= 0x4,
+	[RNG_CONFIG_REG]	= 0x28,
+	[RNG_REV_REG]		= 0x3c,
+	[RNG_SYSCONFIG_REG]	= 0x40,
+};
 
+static const u16 reg_map_omap4[] = {
+	[RNG_OUTPUT_L_REG]	= 0x0,
+	[RNG_OUTPUT_H_REG]	= 0x4,
+	[RNG_STATUS_REG]	= 0x8,
+	[RNG_INTMASK_REG]	= 0xc,
+	[RNG_INTACK_REG]	= 0x10,
+	[RNG_CONTROL_REG]	= 0x14,
+	[RNG_CONFIG_REG]	= 0x18,
+	[RNG_ALARMCNT_REG]	= 0x1c,
+	[RNG_FROENABLE_REG]	= 0x20,
+	[RNG_FRODETUNE_REG]	= 0x24,
+	[RNG_ALARMMASK_REG]	= 0x28,
+	[RNG_ALARMSTOP_REG]	= 0x2c,
+	[RNG_REV_REG]		= 0x1FE0,
+	[RNG_SYSCONFIG_REG]	= 0x1FE4,
+};
+
+struct omap_rng_dev;
 /**
- * struct omap_rng_private_data - RNG IP block-specific data
- * @base: virtual address of the beginning of the RNG IP block registers
- * @mem_res: struct resource * for the IP block registers physical memory
+ * struct omap_rng_pdata - RNG IP block-specific data
+ * @regs: Pointer to the register offsets structure.
+ * @data_size: No. of bytes in RNG output.
+ * @data_present: Callback to determine if data is available.
+ * @init: Callback for IP specific initialization sequence.
+ * @cleanup: Callback for IP specific cleanup sequence.
  */
-struct omap_rng_private_data {
-	void __iomem *base;
-	struct resource *mem_res;
+struct omap_rng_pdata {
+	u16	*regs;
+	u32	data_size;
+	u32	(*data_present)(struct omap_rng_dev *priv);
+	int	(*init)(struct omap_rng_dev *priv);
+	void	(*cleanup)(struct omap_rng_dev *priv);
 };
 
-static inline u32 omap_rng_read_reg(struct omap_rng_private_data *priv, int reg)
+struct omap_rng_dev {
+	void __iomem			*base;
+	struct device			*dev;
+	const struct omap_rng_pdata	*pdata;
+};
+
+static inline u32 omap_rng_read(struct omap_rng_dev *priv, u16 reg)
 {
-	return __raw_readl(priv->base + reg);
+	return __raw_readl(priv->base + priv->pdata->regs[reg]);
 }
 
-static inline void omap_rng_write_reg(struct omap_rng_private_data *priv,
-				      int reg, u32 val)
+static inline void omap_rng_write(struct omap_rng_dev *priv, u16 reg,
+				      u32 val)
 {
-	__raw_writel(val, priv->base + reg);
+	__raw_writel(val, priv->base + priv->pdata->regs[reg]);
 }
 
 static int omap_rng_data_present(struct hwrng *rng, int wait)
 {
-	struct omap_rng_private_data *priv;
+	struct omap_rng_dev *priv;
 	int data, i;
 
-	priv = (struct omap_rng_private_data *)rng->priv;
+	priv = (struct omap_rng_dev *)rng->priv;
 
 	for (i = 0; i < 20; i++) {
-		data = omap_rng_read_reg(priv, RNG_STAT_REG) ? 0 : 1;
+		data = priv->pdata->data_present(priv);
 		if (data || !wait)
 			break;
 		/* RNG produces data fast enough (2+ MBit/sec, even
@@ -89,27 +163,212 @@ static int omap_rng_data_present(struct hwrng *rng, int wait)
 
 static int omap_rng_data_read(struct hwrng *rng, u32 *data)
 {
-	struct omap_rng_private_data *priv;
+	struct omap_rng_dev *priv;
+	u32 data_size, i;
+
+	priv = (struct omap_rng_dev *)rng->priv;
+	data_size = priv->pdata->data_size;
+
+	for (i = 0; i < data_size / sizeof(u32); i++)
+		data[i] = omap_rng_read(priv, RNG_OUTPUT_L_REG + i);
+
+	if (priv->pdata->regs[RNG_INTACK_REG])
+		omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_RDY_MASK);
+	return data_size;
+}
+
+static int omap_rng_init(struct hwrng *rng)
+{
+	struct omap_rng_dev *priv;
 
-	priv = (struct omap_rng_private_data *)rng->priv;
+	priv = (struct omap_rng_dev *)rng->priv;
+	return priv->pdata->init(priv);
+}
 
-	*data = omap_rng_read_reg(priv, RNG_OUT_REG);
+static void omap_rng_cleanup(struct hwrng *rng)
+{
+	struct omap_rng_dev *priv;
 
-	return sizeof(u32);
+	priv = (struct omap_rng_dev *)rng->priv;
+	priv->pdata->cleanup(priv);
 }
 
 static struct hwrng omap_rng_ops = {
 	.name		= "omap",
 	.data_present	= omap_rng_data_present,
 	.data_read	= omap_rng_data_read,
+	.init		= omap_rng_init,
+	.cleanup	= omap_rng_cleanup,
+};
+
+static inline u32 omap2_rng_data_present(struct omap_rng_dev *priv)
+{
+	return omap_rng_read(priv, RNG_STATUS_REG) ? 0 : 1;
+}
+
+static int omap2_rng_init(struct omap_rng_dev *priv)
+{
+	omap_rng_write(priv, RNG_SYSCONFIG_REG, 0x1);
+	return 0;
+}
+
+static void omap2_rng_cleanup(struct omap_rng_dev *priv)
+{
+	omap_rng_write(priv, RNG_SYSCONFIG_REG, 0x0);
+}
+
+static struct omap_rng_pdata omap2_rng_pdata = {
+	.regs		= (u16 *)reg_map_omap2,
+	.data_size	= OMAP2_RNG_OUTPUT_SIZE,
+	.data_present	= omap2_rng_data_present,
+	.init		= omap2_rng_init,
+	.cleanup	= omap2_rng_cleanup,
 };
 
+#if defined(CONFIG_OF)
+static inline u32 omap4_rng_data_present(struct omap_rng_dev *priv)
+{
+	return omap_rng_read(priv, RNG_STATUS_REG) & RNG_REG_STATUS_RDY;
+}
+
+static int omap4_rng_init(struct omap_rng_dev *priv)
+{
+	u32 val;
+
+	/* Return if RNG is already running. */
+	if (omap_rng_read(priv, RNG_CONFIG_REG) & RNG_CONTROL_ENABLE_TRNG_MASK)
+		return 0;
+
+	val = RNG_CONFIG_MIN_REFIL_CYCLES << RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT;
+	val |= RNG_CONFIG_MAX_REFIL_CYCLES << RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT;
+	omap_rng_write(priv, RNG_CONFIG_REG, val);
+
+	omap_rng_write(priv, RNG_FRODETUNE_REG, 0x0);
+	omap_rng_write(priv, RNG_FROENABLE_REG, RNG_REG_FROENABLE_MASK);
+	val = RNG_ALARM_THRESHOLD << RNG_ALARMCNT_ALARM_TH_SHIFT;
+	val |= RNG_SHUTDOWN_THRESHOLD << RNG_ALARMCNT_SHUTDOWN_TH_SHIFT;
+	omap_rng_write(priv, RNG_ALARMCNT_REG, val);
+
+	val = RNG_CONTROL_STARTUP_CYCLES << RNG_CONTROL_STARTUP_CYCLES_SHIFT;
+	val |= RNG_CONTROL_ENABLE_TRNG_MASK;
+	omap_rng_write(priv, RNG_CONTROL_REG, val);
+
+	return 0;
+}
+
+static void omap4_rng_cleanup(struct omap_rng_dev *priv)
+{
+	int val;
+
+	val = omap_rng_read(priv, RNG_CONTROL_REG);
+	val &= ~RNG_CONTROL_ENABLE_TRNG_MASK;
+	omap_rng_write(priv, RNG_CONFIG_REG, val);
+}
+
+static irqreturn_t omap4_rng_irq(int irq, void *dev_id)
+{
+	struct omap_rng_dev *priv = dev_id;
+	u32 fro_detune, fro_enable;
+
+	/*
+	 * Interrupt raised by a fro shutdown threshold, do the following:
+	 * 1. Clear the alarm events.
+	 * 2. De tune the FROs which are shutdown.
+	 * 3. Re enable the shutdown FROs.
+	 */
+	omap_rng_write(priv, RNG_ALARMMASK_REG, 0x0);
+	omap_rng_write(priv, RNG_ALARMSTOP_REG, 0x0);
+
+	fro_enable = omap_rng_read(priv, RNG_FROENABLE_REG);
+	fro_detune = ~fro_enable & RNG_REG_FRODETUNE_MASK;
+	fro_detune = fro_detune | omap_rng_read(priv, RNG_FRODETUNE_REG);
+	fro_enable = RNG_REG_FROENABLE_MASK;
+
+	omap_rng_write(priv, RNG_FRODETUNE_REG, fro_detune);
+	omap_rng_write(priv, RNG_FROENABLE_REG, fro_enable);
+
+	omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_SHUTDOWN_OFLO_MASK);
+
+	return IRQ_HANDLED;
+}
+
+static struct omap_rng_pdata omap4_rng_pdata = {
+	.regs		= (u16 *)reg_map_omap4,
+	.data_size	= OMAP4_RNG_OUTPUT_SIZE,
+	.data_present	= omap4_rng_data_present,
+	.init		= omap4_rng_init,
+	.cleanup	= omap4_rng_cleanup,
+};
+
+static const struct of_device_id omap_rng_of_match[] = {
+		{
+			.compatible	= "ti,omap2-rng",
+			.data		= &omap2_rng_pdata,
+		},
+		{
+			.compatible	= "ti,omap4-rng",
+			.data		= &omap4_rng_pdata,
+		},
+		{},
+};
+MODULE_DEVICE_TABLE(of, omap_rng_of_match);
+
+static int of_get_omap_rng_device_details(struct omap_rng_dev *priv,
+					  struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	struct device *dev = &pdev->dev;
+	int irq, err;
+
+	match = of_match_device(of_match_ptr(omap_rng_of_match), dev);
+	if (!match) {
+		dev_err(dev, "no compatible OF match\n");
+		return -EINVAL;
+	}
+	priv->pdata = match->data;
+
+	if (of_device_is_compatible(dev->of_node, "ti,omap4-rng")) {
+		irq = platform_get_irq(pdev, 0);
+		if (irq < 0) {
+			dev_err(dev, "%s: error getting IRQ resource - %d\n",
+				__func__, irq);
+			return irq;
+		}
+
+		err = devm_request_irq(dev, irq, omap4_rng_irq,
+				       IRQF_TRIGGER_NONE, dev_name(dev), priv);
+		if (err) {
+			dev_err(dev, "unable to request irq %d, err = %d\n",
+				irq, err);
+			return err;
+		}
+		omap_rng_write(priv, RNG_INTMASK_REG, RNG_SHUTDOWN_OFLO_MASK);
+	}
+	return 0;
+}
+#else
+static int of_get_omap_rng_device_details(struct omap_rng_dev *omap_rng,
+					  struct platform_device *pdev)
+{
+	return -EINVAL;
+}
+#endif
+
+static int get_omap_rng_device_details(struct omap_rng_dev *omap_rng)
+{
+	/* Only OMAP2/3 can be non-DT */
+	omap_rng->pdata = &omap2_rng_pdata;
+	return 0;
+}
+
 static int omap_rng_probe(struct platform_device *pdev)
 {
-	struct omap_rng_private_data *priv;
+	struct omap_rng_dev *priv;
+	struct resource *res;
+	struct device *dev = &pdev->dev;
 	int ret;
 
-	priv = kzalloc(sizeof(struct omap_rng_private_data), GFP_KERNEL);
+	priv = devm_kzalloc(dev, sizeof(struct omap_rng_dev), GFP_KERNEL);
 	if (!priv) {
 		dev_err(&pdev->dev, "could not allocate memory\n");
 		return -ENOMEM;
@@ -117,26 +376,29 @@ static int omap_rng_probe(struct platform_device *pdev)
 
 	omap_rng_ops.priv = (unsigned long)priv;
 	platform_set_drvdata(pdev, priv);
+	priv->dev = dev;
 
-	priv->mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	priv->base = devm_ioremap_resource(&pdev->dev, priv->mem_res);
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(priv->base)) {
 		ret = PTR_ERR(priv->base);
 		goto err_ioremap;
 	}
-	platform_set_drvdata(pdev, priv);
 
 	pm_runtime_enable(&pdev->dev);
 	pm_runtime_get_sync(&pdev->dev);
 
+	ret = (dev->of_node) ? of_get_omap_rng_device_details(priv, pdev) :
+				get_omap_rng_device_details(priv);
+	if (ret)
+		goto err_ioremap;
+
 	ret = hwrng_register(&omap_rng_ops);
 	if (ret)
 		goto err_register;
 
 	dev_info(&pdev->dev, "OMAP Random Number Generator ver. %02x\n",
-		 omap_rng_read_reg(priv, RNG_REV_REG));
-
-	omap_rng_write_reg(priv, RNG_MASK_REG, 0x1);
+		 omap_rng_read(priv, RNG_REV_REG));
 
 	return 0;
 
@@ -144,26 +406,21 @@ err_register:
 	priv->base = NULL;
 	pm_runtime_disable(&pdev->dev);
 err_ioremap:
-	kfree(priv);
-
+	dev_err(dev, "initialization failed.\n");
 	return ret;
 }
 
 static int __exit omap_rng_remove(struct platform_device *pdev)
 {
-	struct omap_rng_private_data *priv = platform_get_drvdata(pdev);
+	struct omap_rng_dev *priv = platform_get_drvdata(pdev);
 
 	hwrng_unregister(&omap_rng_ops);
 
-	omap_rng_write_reg(priv, RNG_MASK_REG, 0x0);
+	priv->pdata->cleanup(priv);
 
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
-	release_mem_region(priv->mem_res->start, resource_size(priv->mem_res));
-
-	kfree(priv);
-
 	return 0;
 }
 
@@ -171,9 +428,9 @@ static int __exit omap_rng_remove(struct platform_device *pdev)
 
 static int omap_rng_suspend(struct device *dev)
 {
-	struct omap_rng_private_data *priv = dev_get_drvdata(dev);
+	struct omap_rng_dev *priv = dev_get_drvdata(dev);
 
-	omap_rng_write_reg(priv, RNG_MASK_REG, 0x0);
+	priv->pdata->cleanup(priv);
 	pm_runtime_put_sync(dev);
 
 	return 0;
@@ -181,10 +438,10 @@ static int omap_rng_suspend(struct device *dev)
 
 static int omap_rng_resume(struct device *dev)
 {
-	struct omap_rng_private_data *priv = dev_get_drvdata(dev);
+	struct omap_rng_dev *priv = dev_get_drvdata(dev);
 
 	pm_runtime_get_sync(dev);
-	omap_rng_write_reg(priv, RNG_MASK_REG, 0x1);
+	priv->pdata->init(priv);
 
 	return 0;
 }
@@ -198,31 +455,18 @@ static SIMPLE_DEV_PM_OPS(omap_rng_pm, omap_rng_suspend, omap_rng_resume);
 
 #endif
 
-/* work with hotplug and coldplug */
-MODULE_ALIAS("platform:omap_rng");
-
 static struct platform_driver omap_rng_driver = {
 	.driver = {
 		.name		= "omap_rng",
 		.owner		= THIS_MODULE,
 		.pm		= OMAP_RNG_PM,
+		.of_match_table = of_match_ptr(omap_rng_of_match),
 	},
 	.probe		= omap_rng_probe,
 	.remove		= __exit_p(omap_rng_remove),
 };
 
-static int __init omap_rng_init(void)
-{
-	return platform_driver_register(&omap_rng_driver);
-}
-
-static void __exit omap_rng_exit(void)
-{
-	platform_driver_unregister(&omap_rng_driver);
-}
-
-module_init(omap_rng_init);
-module_exit(omap_rng_exit);
-
+module_platform_driver(omap_rng_driver);
+MODULE_ALIAS("platform:omap_rng");
 MODULE_AUTHOR("Deepak Saxena (and others)");
 MODULE_LICENSE("GPL");