[PATCH 4/4] crypto/talitos: add hwrng support
Kim Phillips
kim.phillips at freescale.com
Tue Jun 17 02:10:53 EST 2008
register with the hwrng subsystem to provide entropy to the kernel.
Signed-off-by: Kim Phillips <kim.phillips at freescale.com>
---
drivers/crypto/Kconfig | 1 +
drivers/crypto/talitos.c | 136 ++++++++++++++++++++++++++++++++++++++--------
drivers/crypto/talitos.h | 13 ++++-
3 files changed, 126 insertions(+), 24 deletions(-)
diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index 98d96df..249c135 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -178,6 +178,7 @@ config CRYPTO_DEV_TALITOS
tristate "Talitos Freescale Security Engine (SEC)"
select CRYPTO_ALGAPI
select CRYPTO_AUTHENC
+ select HW_RANDOM
depends on FSL_SOC
help
Say 'Y' here to use the Freescale Security Engine (SEC)
diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index 64ddad2..e123312 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -124,6 +124,9 @@ struct talitos_private {
/* list of registered algorithms */
struct list_head alg_list;
+
+ /* hwrng device */
+ struct hwrng rng;
};
/*
@@ -523,8 +526,8 @@ static void talitos_error(unsigned long data)
}
}
}
- if (reset_dev || isr & ~TALITOS_ISR_CHERR) {
- dev_err(dev, "done overflow or internal time out error: "
+ if (reset_dev || isr & ~TALITOS_ISR_CHERR || isr_lo) {
+ dev_err(dev, "done overflow, internal time out, or rngu error: "
"ISR 0x%08x_%08x\n", isr, isr_lo);
/* purge request queues */
@@ -549,7 +552,7 @@ static irqreturn_t talitos_interrupt(int irq, void *data)
out_be32(priv->reg + TALITOS_ICR, isr);
out_be32(priv->reg + TALITOS_ICR_LO, isr_lo);
- if (unlikely(isr & ~TALITOS_ISR_CHDONE))
+ if (unlikely((isr & ~TALITOS_ISR_CHDONE) || isr_lo))
talitos_error((unsigned long)data);
else
if (likely(isr & TALITOS_ISR_CHDONE))
@@ -559,6 +562,80 @@ static irqreturn_t talitos_interrupt(int irq, void *data)
}
/*
+ * hwrng
+ */
+static int talitos_rng_data_present(struct hwrng *rng, int wait)
+{
+ struct device *dev = (struct device *)rng->priv;
+ struct talitos_private *priv = dev_get_drvdata(dev);
+ u32 ofl;
+ int i;
+
+ for (i = 0; i < 20; i++) {
+ ofl = in_be32(priv->reg + TALITOS_RNGUSR_LO) &
+ TALITOS_RNGUSR_LO_OFL;
+ if (ofl || !wait)
+ break;
+ udelay(10);
+ }
+
+ return !!ofl;
+}
+
+static int talitos_rng_data_read(struct hwrng *rng, u32 *data)
+{
+ struct device *dev = (struct device *)rng->priv;
+ struct talitos_private *priv = dev_get_drvdata(dev);
+
+ /* rng fifo requires 64-bit accesses */
+ *data = in_be32(priv->reg + TALITOS_RNGU_FIFO);
+ *data = in_be32(priv->reg + TALITOS_RNGU_FIFO_LO);
+
+ return sizeof(u32);
+}
+
+static int talitos_rng_init(struct hwrng *rng)
+{
+ struct device *dev = (struct device *)rng->priv;
+ struct talitos_private *priv = dev_get_drvdata(dev);
+ unsigned int timeout = TALITOS_TIMEOUT;
+
+ setbits32(priv->reg + TALITOS_RNGURCR_LO, TALITOS_RNGURCR_LO_SR);
+ while (!(in_be32(priv->reg + TALITOS_RNGUSR_LO) & TALITOS_RNGUSR_LO_RD)
+ && --timeout)
+ cpu_relax();
+ if (timeout == 0) {
+ dev_err(dev, "failed to reset rng hw\n");
+ return -ENODEV;
+ }
+
+ /* start generating */
+ setbits32(priv->reg + TALITOS_RNGUDSR_LO, 0);
+
+ return 0;
+}
+
+static int talitos_register_rng(struct device *dev)
+{
+ struct talitos_private *priv = dev_get_drvdata(dev);
+
+ priv->rng.name = dev_driver_string(dev),
+ priv->rng.init = talitos_rng_init,
+ priv->rng.data_present = talitos_rng_data_present,
+ priv->rng.data_read = talitos_rng_data_read,
+ priv->rng.priv = (unsigned long)dev;
+
+ return hwrng_register(&priv->rng);
+}
+
+static void talitos_unregister_rng(struct device *dev)
+{
+ struct talitos_private *priv = dev_get_drvdata(dev);
+
+ hwrng_unregister(&priv->rng);
+}
+
+/*
* crypto alg
*/
#define TALITOS_CRA_PRIORITY 3000
@@ -1094,6 +1171,26 @@ static int talitos_cra_init(struct crypto_tfm *tfm)
return 0;
}
+/*
+ * given the alg's descriptor header template, determine whether descriptor
+ * type and primary/secondary execution units required match the hw
+ * capabilities description provided in the device tree node.
+ */
+static int hw_supports(struct device *dev, __be32 desc_hdr_template)
+{
+ struct talitos_private *priv = dev_get_drvdata(dev);
+ int ret;
+
+ ret = (1 << DESC_TYPE(desc_hdr_template) & priv->desc_types) &&
+ (1 << PRIMARY_EU(desc_hdr_template) & priv->exec_units);
+
+ if (SECONDARY_EU(desc_hdr_template))
+ ret = ret && (1 << SECONDARY_EU(desc_hdr_template)
+ & priv->exec_units);
+
+ return ret;
+}
+
static int __devexit talitos_remove(struct of_device *ofdev)
{
struct device *dev = &ofdev->dev;
@@ -1107,6 +1204,9 @@ static int __devexit talitos_remove(struct of_device *ofdev)
kfree(t_alg);
}
+ if (hw_supports(dev, DESC_HDR_SEL0_RNG))
+ talitos_unregister_rng(dev);
+
kfree(priv->tail);
kfree(priv->head);
@@ -1167,26 +1267,6 @@ static struct talitos_crypto_alg *talitos_alg_alloc(struct device *dev,
return t_alg;
}
-/*
- * given the alg's descriptor header template, determine whether descriptor
- * type and primary/secondary execution units required match the hw
- * capabilities description provided in the device tree node.
- */
-static int hw_supports(struct device *dev, __be32 desc_hdr_template)
-{
- struct talitos_private *priv = dev_get_drvdata(dev);
- int ret;
-
- ret = (1 << DESC_TYPE(desc_hdr_template) & priv->desc_types) &&
- (1 << PRIMARY_EU(desc_hdr_template) & priv->exec_units);
-
- if (SECONDARY_EU(desc_hdr_template))
- ret = ret && (1 << SECONDARY_EU(desc_hdr_template)
- & priv->exec_units);
-
- return ret;
-}
-
static int talitos_probe(struct of_device *ofdev,
const struct of_device_id *match)
{
@@ -1309,6 +1389,16 @@ static int talitos_probe(struct of_device *ofdev,
goto err_out;
}
+ /* register the RNG, if available */
+ if (hw_supports(dev, DESC_HDR_SEL0_RNG)) {
+ err = talitos_register_rng(dev);
+ if (err) {
+ dev_err(dev, "failed to register hwrng: %d\n", err);
+ goto err_out;
+ } else
+ dev_info(dev, "hwrng\n");
+ }
+
/* register crypto algorithms the device supports */
INIT_LIST_HEAD(&priv->alg_list);
diff --git a/drivers/crypto/talitos.h b/drivers/crypto/talitos.h
index 27deb65..de0e377 100644
--- a/drivers/crypto/talitos.h
+++ b/drivers/crypto/talitos.h
@@ -39,7 +39,7 @@
#define TALITOS_IMR 0x1008 /* interrupt mask register */
#define TALITOS_IMR_INIT 0x10fff /* enable channel IRQs */
#define TALITOS_IMR_LO 0x100C
-#define TALITOS_IMR_LO_INIT 0x0 /* disable execution unit IRQs*/
+#define TALITOS_IMR_LO_INIT 0x20000 /* allow RNGU error IRQs */
#define TALITOS_ISR 0x1010 /* interrupt status register */
#define TALITOS_ISR_CHERR 0xaa /* channel errors mask */
#define TALITOS_ISR_CHDONE 0x55 /* channel done mask */
@@ -106,6 +106,17 @@
#define TALITOS_AFEUISR_LO 0x8034
#define TALITOS_RNGUISR 0xa030 /* random number unit */
#define TALITOS_RNGUISR_LO 0xa034
+#define TALITOS_RNGUSR 0xa028 /* rng status */
+#define TALITOS_RNGUSR_LO 0xa02c
+#define TALITOS_RNGUSR_LO_RD 0x1 /* reset done */
+#define TALITOS_RNGUSR_LO_OFL 0xff0000/* output FIFO length */
+#define TALITOS_RNGUDSR 0xa010 /* data size */
+#define TALITOS_RNGUDSR_LO 0xa014
+#define TALITOS_RNGU_FIFO 0xa800 /* output FIFO */
+#define TALITOS_RNGU_FIFO_LO 0xa804 /* output FIFO */
+#define TALITOS_RNGURCR 0xa018 /* reset control */
+#define TALITOS_RNGURCR_LO 0xa01c
+#define TALITOS_RNGURCR_LO_SR 0x1 /* software reset */
#define TALITOS_PKEUISR 0xc030 /* public key unit */
#define TALITOS_PKEUISR_LO 0xc034
#define TALITOS_KEUISR 0xe030 /* kasumi unit */
--
1.5.6.rc2.26.g8c37
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