1 files changed, 92 insertions, 48 deletions

diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c
index d5fe5f57108c..3ad032f570ae 100644
--- a/drivers/crypto/caam/ctrl.c
+++ b/drivers/crypto/caam/ctrl.c
@@ -13,39 +13,6 @@
 #include "error.h"
 #include "ctrl.h"
 
-static int caam_remove(struct platform_device *pdev)
-{
-	struct device *ctrldev;
-	struct caam_drv_private *ctrlpriv;
-	struct caam_drv_private_jr *jrpriv;
-	struct caam_full __iomem *topregs;
-	int ring, ret = 0;
-
-	ctrldev = &pdev->dev;
-	ctrlpriv = dev_get_drvdata(ctrldev);
-	topregs = (struct caam_full __iomem *)ctrlpriv->ctrl;
-
-	/* shut down JobRs */
-	for (ring = 0; ring < ctrlpriv->total_jobrs; ring++) {
-		ret |= caam_jr_shutdown(ctrlpriv->jrdev[ring]);
-		jrpriv = dev_get_drvdata(ctrlpriv->jrdev[ring]);
-		irq_dispose_mapping(jrpriv->irq);
-	}
-
-	/* Shut down debug views */
-#ifdef CONFIG_DEBUG_FS
-	debugfs_remove_recursive(ctrlpriv->dfs_root);
-#endif
-
-	/* Unmap controller region */
-	iounmap(&topregs->ctrl);
-
-	kfree(ctrlpriv->jrdev);
-	kfree(ctrlpriv);
-
-	return ret;
-}
-
 /*
  * Descriptor to instantiate RNG State Handle 0 in normal mode and
  * load the JDKEK, TDKEK and TDSK registers
@@ -77,21 +44,23 @@ static void build_instantiation_desc(u32 *desc)
 	append_jump(desc, JUMP_CLASS_CLASS1 | JUMP_TYPE_HALT);
 }
 
-static int instantiate_rng(struct device *ctrldev)
+
+/*
+ * run_descriptor_deco0 - runs a descriptor on DECO0, under direct control of
+ *			  the software (no JR/QI used).
+ * @ctrldev - pointer to device
+ * Return: - 0 if no error occurred
+ *	   - -ENODEV if the DECO couldn't be acquired
+ *	   - -EAGAIN if an error occurred while executing the descriptor
+ */
+static inline int run_descriptor_deco0(struct device *ctrldev, u32 *desc)
 {
 	struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev);
 	struct caam_full __iomem *topregs;
 	unsigned int timeout = 100000;
-	u32 *desc, deco_dbg_reg;
+	u32 deco_dbg_reg, flags;
 	int i, ret = 0;
 
-	desc = kmalloc(CAAM_CMD_SZ * 7, GFP_KERNEL | GFP_DMA);
-	if (!desc) {
-		dev_err(ctrldev, "can't allocate RNG init descriptor memory\n");
-		return -ENOMEM;
-	}
-	build_instantiation_desc(desc);
-
 	/* Set the bit to request direct access to DECO0 */
 	topregs = (struct caam_full __iomem *)ctrlpriv->ctrl;
 	setbits32(&topregs->ctrl.deco_rq, DECORR_RQD0ENABLE);
@@ -102,14 +71,23 @@ static int instantiate_rng(struct device *ctrldev)
 
 	if (!timeout) {
 		dev_err(ctrldev, "failed to acquire DECO 0\n");
-		ret = -EIO;
-		goto out;
+		clrbits32(&topregs->ctrl.deco_rq, DECORR_RQD0ENABLE);
+		return -ENODEV;
 	}
 
 	for (i = 0; i < desc_len(desc); i++)
-		topregs->deco.descbuf[i] = *(desc + i);
+		wr_reg32(&topregs->deco.descbuf[i], *(desc + i));
 
-	wr_reg32(&topregs->deco.jr_ctl_hi, DECO_JQCR_WHL | DECO_JQCR_FOUR);
+	flags = DECO_JQCR_WHL;
+	/*
+	 * If the descriptor length is longer than 4 words, then the
+	 * FOUR bit in JRCTRL register must be set.
+	 */
+	if (desc_len(desc) >= 4)
+		flags |= DECO_JQCR_FOUR;
+
+	/* Instruct the DECO to execute it */
+	wr_reg32(&topregs->deco.jr_ctl_hi, flags);
 
 	timeout = 10000000;
 	do {
@@ -129,9 +107,75 @@ static int instantiate_rng(struct device *ctrldev)
 		ret = -EIO;
 	}
 
+	/* Mark the DECO as free */
 	clrbits32(&topregs->ctrl.deco_rq, DECORR_RQD0ENABLE);
-out:
+
+	if (!timeout)
+		return -EAGAIN;
+
+	return 0;
+}
+
+/*
+ * instantiate_rng - builds and executes a descriptor on DECO0,
+ *		     which initializes the RNG block.
+ * @ctrldev - pointer to device
+ * Return: - 0 if no error occurred
+ *	   - -ENOMEM if there isn't enough memory to allocate the descriptor
+ *	   - -ENODEV if DECO0 couldn't be acquired
+ *	   - -EAGAIN if an error occurred when executing the descriptor
+ *	      f.i. there was a RNG hardware error due to not "good enough"
+ *	      entropy being aquired.
+ */
+static int instantiate_rng(struct device *ctrldev)
+{
+	u32 *desc;
+	int ret = 0;
+
+	desc = kmalloc(CAAM_CMD_SZ * 7, GFP_KERNEL);
+	if (!desc)
+		return -ENOMEM;
+	/* Create the descriptor for instantiating RNG State Handle 0 */
+	build_instantiation_desc(desc);
+
+	/* Try to run it through DECO0 */
+	ret = run_descriptor_deco0(ctrldev, desc);
+
 	kfree(desc);
+
+	return ret;
+}
+
+static int caam_remove(struct platform_device *pdev)
+{
+	struct device *ctrldev;
+	struct caam_drv_private *ctrlpriv;
+	struct caam_drv_private_jr *jrpriv;
+	struct caam_full __iomem *topregs;
+	int ring, ret = 0;
+
+	ctrldev = &pdev->dev;
+	ctrlpriv = dev_get_drvdata(ctrldev);
+	topregs = (struct caam_full __iomem *)ctrlpriv->ctrl;
+
+	/* shut down JobRs */
+	for (ring = 0; ring < ctrlpriv->total_jobrs; ring++) {
+		ret |= caam_jr_shutdown(ctrlpriv->jrdev[ring]);
+		jrpriv = dev_get_drvdata(ctrlpriv->jrdev[ring]);
+		irq_dispose_mapping(jrpriv->irq);
+	}
+
+	/* Shut down debug views */
+#ifdef CONFIG_DEBUG_FS
+	debugfs_remove_recursive(ctrlpriv->dfs_root);
+#endif
+
+	/* Unmap controller region */
+	iounmap(&topregs->ctrl);
+
+	kfree(ctrlpriv->jrdev);
+	kfree(ctrlpriv);
+
 	return ret;
 }
 
@@ -333,7 +377,7 @@ static int caam_probe(struct platform_device *pdev)
 			kick_trng(pdev, ent_delay);
 			ret = instantiate_rng(dev);
 			ent_delay += 400;
-		} while ((ret == -EIO) && (ent_delay < RTSDCTL_ENT_DLY_MAX));
+		} while ((ret == -EAGAIN) && (ent_delay < RTSDCTL_ENT_DLY_MAX));
 		if (ret) {
 			dev_err(dev, "failed to instantiate RNG");
 			caam_remove(pdev);