1 files changed, 122 insertions, 40 deletions

diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c
index f5c26a5f6875..3ad86fdf954e 100644
--- a/drivers/char/hw_random/omap-rng.c
+++ b/drivers/char/hw_random/omap-rng.c
@@ -28,6 +28,7 @@
 #include <linux/of_device.h>
 #include <linux/of_address.h>
 #include <linux/interrupt.h>
+#include <linux/clk.h>
 
 #include <asm/io.h>
 
@@ -63,10 +64,13 @@
 
 #define OMAP2_RNG_OUTPUT_SIZE			0x4
 #define OMAP4_RNG_OUTPUT_SIZE			0x8
+#define EIP76_RNG_OUTPUT_SIZE			0x10
 
 enum {
-	RNG_OUTPUT_L_REG = 0,
-	RNG_OUTPUT_H_REG,
+	RNG_OUTPUT_0_REG = 0,
+	RNG_OUTPUT_1_REG,
+	RNG_OUTPUT_2_REG,
+	RNG_OUTPUT_3_REG,
 	RNG_STATUS_REG,
 	RNG_INTMASK_REG,
 	RNG_INTACK_REG,
@@ -82,7 +86,7 @@ enum {
 };
 
 static const u16 reg_map_omap2[] = {
-	[RNG_OUTPUT_L_REG]	= 0x0,
+	[RNG_OUTPUT_0_REG]	= 0x0,
 	[RNG_STATUS_REG]	= 0x4,
 	[RNG_CONFIG_REG]	= 0x28,
 	[RNG_REV_REG]		= 0x3c,
@@ -90,8 +94,8 @@ static const u16 reg_map_omap2[] = {
 };
 
 static const u16 reg_map_omap4[] = {
-	[RNG_OUTPUT_L_REG]	= 0x0,
-	[RNG_OUTPUT_H_REG]	= 0x4,
+	[RNG_OUTPUT_0_REG]	= 0x0,
+	[RNG_OUTPUT_1_REG]	= 0x4,
 	[RNG_STATUS_REG]	= 0x8,
 	[RNG_INTMASK_REG]	= 0xc,
 	[RNG_INTACK_REG]	= 0x10,
@@ -106,6 +110,23 @@ static const u16 reg_map_omap4[] = {
 	[RNG_SYSCONFIG_REG]	= 0x1FE4,
 };
 
+static const u16 reg_map_eip76[] = {
+	[RNG_OUTPUT_0_REG]	= 0x0,
+	[RNG_OUTPUT_1_REG]	= 0x4,
+	[RNG_OUTPUT_2_REG]	= 0x8,
+	[RNG_OUTPUT_3_REG]	= 0xc,
+	[RNG_STATUS_REG]	= 0x10,
+	[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]		= 0x7c,
+};
+
 struct omap_rng_dev;
 /**
  * struct omap_rng_pdata - RNG IP block-specific data
@@ -127,6 +148,8 @@ struct omap_rng_dev {
 	void __iomem			*base;
 	struct device			*dev;
 	const struct omap_rng_pdata	*pdata;
+	struct hwrng rng;
+	struct clk 			*clk;
 };
 
 static inline u32 omap_rng_read(struct omap_rng_dev *priv, u16 reg)
@@ -140,41 +163,35 @@ static inline void omap_rng_write(struct omap_rng_dev *priv, u16 reg,
 	__raw_writel(val, priv->base + priv->pdata->regs[reg]);
 }
 
-static int omap_rng_data_present(struct hwrng *rng, int wait)
+
+static int omap_rng_do_read(struct hwrng *rng, void *data, size_t max,
+			    bool wait)
 {
 	struct omap_rng_dev *priv;
-	int data, i;
+	int i, present;
 
 	priv = (struct omap_rng_dev *)rng->priv;
 
+	if (max < priv->pdata->data_size)
+		return 0;
+
 	for (i = 0; i < 20; i++) {
-		data = priv->pdata->data_present(priv);
-		if (data || !wait)
+		present = priv->pdata->data_present(priv);
+		if (present || !wait)
 			break;
-		/* RNG produces data fast enough (2+ MBit/sec, even
-		 * during "rngtest" loads, that these delays don't
-		 * seem to trigger.  We *could* use the RNG IRQ, but
-		 * that'd be higher overhead ... so why bother?
-		 */
+
 		udelay(10);
 	}
-	return data;
-}
-
-static int omap_rng_data_read(struct hwrng *rng, u32 *data)
-{
-	struct omap_rng_dev *priv;
-	u32 data_size, i;
-
-	priv = (struct omap_rng_dev *)rng->priv;
-	data_size = priv->pdata->data_size;
+	if (!present)
+		return 0;
 
-	for (i = 0; i < data_size / sizeof(u32); i++)
-		data[i] = omap_rng_read(priv, RNG_OUTPUT_L_REG + i);
+	memcpy_fromio(data, priv->base + priv->pdata->regs[RNG_OUTPUT_0_REG],
+		      priv->pdata->data_size);
 
 	if (priv->pdata->regs[RNG_INTACK_REG])
 		omap_rng_write(priv, RNG_INTACK_REG, RNG_REG_INTACK_RDY_MASK);
-	return data_size;
+
+	return priv->pdata->data_size;
 }
 
 static int omap_rng_init(struct hwrng *rng)
@@ -193,13 +210,6 @@ static void omap_rng_cleanup(struct hwrng *rng)
 	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)
 {
@@ -231,6 +241,38 @@ 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 eip76_rng_init(struct omap_rng_dev *priv)
+{
+	u32 val;
+
+	/* Return if RNG is already running. */
+	if (omap_rng_read(priv, RNG_CONTROL_REG) & RNG_CONTROL_ENABLE_TRNG_MASK)
+		return 0;
+
+	/*  Number of 512 bit blocks of raw Noise Source output data that must
+	 *  be processed by either the Conditioning Function or the
+	 *  SP 800-90 DRBG ‘BC_DF’ functionality to yield a ‘full entropy’
+	 *  output value.
+	 */
+	val = 0x5 << RNG_CONFIG_MIN_REFIL_CYCLES_SHIFT;
+
+	/* Number of FRO samples that are XOR-ed together into one bit to be
+	 * shifted into the main shift register
+	 */
+	val |= RNG_CONFIG_MAX_REFIL_CYCLES << RNG_CONFIG_MAX_REFIL_CYCLES_SHIFT;
+	omap_rng_write(priv, RNG_CONFIG_REG, val);
+
+	/* Enable all available FROs */
+	omap_rng_write(priv, RNG_FRODETUNE_REG, 0x0);
+	omap_rng_write(priv, RNG_FROENABLE_REG, RNG_REG_FROENABLE_MASK);
+
+	/* Enable TRNG */
+	val = RNG_CONTROL_ENABLE_TRNG_MASK;
+	omap_rng_write(priv, RNG_CONTROL_REG, val);
+
+	return 0;
+}
+
 static int omap4_rng_init(struct omap_rng_dev *priv)
 {
 	u32 val;
@@ -300,6 +342,14 @@ static struct omap_rng_pdata omap4_rng_pdata = {
 	.cleanup	= omap4_rng_cleanup,
 };
 
+static struct omap_rng_pdata eip76_rng_pdata = {
+	.regs		= (u16 *)reg_map_eip76,
+	.data_size	= EIP76_RNG_OUTPUT_SIZE,
+	.data_present	= omap4_rng_data_present,
+	.init		= eip76_rng_init,
+	.cleanup	= omap4_rng_cleanup,
+};
+
 static const struct of_device_id omap_rng_of_match[] = {
 		{
 			.compatible	= "ti,omap2-rng",
@@ -309,6 +359,10 @@ static const struct of_device_id omap_rng_of_match[] = {
 			.compatible	= "ti,omap4-rng",
 			.data		= &omap4_rng_pdata,
 		},
+		{
+			.compatible	= "inside-secure,safexcel-eip76",
+			.data		= &eip76_rng_pdata,
+		},
 		{},
 };
 MODULE_DEVICE_TABLE(of, omap_rng_of_match);
@@ -327,7 +381,8 @@ static int of_get_omap_rng_device_details(struct omap_rng_dev *priv,
 	}
 	priv->pdata = match->data;
 
-	if (of_device_is_compatible(dev->of_node, "ti,omap4-rng")) {
+	if (of_device_is_compatible(dev->of_node, "ti,omap4-rng") ||
+	    of_device_is_compatible(dev->of_node, "inside-secure,safexcel-eip76")) {
 		irq = platform_get_irq(pdev, 0);
 		if (irq < 0) {
 			dev_err(dev, "%s: error getting IRQ resource - %d\n",
@@ -343,6 +398,16 @@ static int of_get_omap_rng_device_details(struct omap_rng_dev *priv,
 			return err;
 		}
 		omap_rng_write(priv, RNG_INTMASK_REG, RNG_SHUTDOWN_OFLO_MASK);
+
+		priv->clk = of_clk_get(pdev->dev.of_node, 0);
+		if (IS_ERR(priv->clk) && PTR_ERR(priv->clk) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		if (!IS_ERR(priv->clk)) {
+			err = clk_prepare_enable(priv->clk);
+			if (err)
+				dev_err(&pdev->dev, "unable to enable the clk, "
+						    "err = %d\n", err);
+		}
 	}
 	return 0;
 }
@@ -372,7 +437,11 @@ static int omap_rng_probe(struct platform_device *pdev)
 	if (!priv)
 		return -ENOMEM;
 
-	omap_rng_ops.priv = (unsigned long)priv;
+	priv->rng.read = omap_rng_do_read;
+	priv->rng.init = omap_rng_init;
+	priv->rng.cleanup = omap_rng_cleanup;
+
+	priv->rng.priv = (unsigned long)priv;
 	platform_set_drvdata(pdev, priv);
 	priv->dev = dev;
 
@@ -383,6 +452,12 @@ static int omap_rng_probe(struct platform_device *pdev)
 		goto err_ioremap;
 	}
 
+	priv->rng.name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
+	if (!priv->rng.name) {
+		ret = -ENOMEM;
+		goto err_ioremap;
+	}
+
 	pm_runtime_enable(&pdev->dev);
 	ret = pm_runtime_get_sync(&pdev->dev);
 	if (ret < 0) {
@@ -394,20 +469,24 @@ static int omap_rng_probe(struct platform_device *pdev)
 	ret = (dev->of_node) ? of_get_omap_rng_device_details(priv, pdev) :
 				get_omap_rng_device_details(priv);
 	if (ret)
-		goto err_ioremap;
+		goto err_register;
 
-	ret = hwrng_register(&omap_rng_ops);
+	ret = hwrng_register(&priv->rng);
 	if (ret)
 		goto err_register;
 
-	dev_info(&pdev->dev, "OMAP Random Number Generator ver. %02x\n",
+	dev_info(&pdev->dev, "Random Number Generator ver. %02x\n",
 		 omap_rng_read(priv, RNG_REV_REG));
 
 	return 0;
 
 err_register:
 	priv->base = NULL;
+	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
+
+	if (!IS_ERR(priv->clk))
+		clk_disable_unprepare(priv->clk);
 err_ioremap:
 	dev_err(dev, "initialization failed.\n");
 	return ret;
@@ -417,13 +496,16 @@ static int omap_rng_remove(struct platform_device *pdev)
 {
 	struct omap_rng_dev *priv = platform_get_drvdata(pdev);
 
-	hwrng_unregister(&omap_rng_ops);
+	hwrng_unregister(&priv->rng);
 
 	priv->pdata->cleanup(priv);
 
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
+	if (!IS_ERR(priv->clk))
+		clk_disable_unprepare(priv->clk);
+
 	return 0;
 }