1 files changed, 331 insertions, 87 deletions

diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c
index bc6d820..63fb1af 100644
--- a/drivers/crypto/caam/ctrl.c
+++ b/drivers/crypto/caam/ctrl.c
@@ -16,82 +16,75 @@
 #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
  */
-static void build_instantiation_desc(u32 *desc)
+static void build_instantiation_desc(u32 *desc, int handle, int do_sk)
 {
-	u32 *jump_cmd;
+	u32 *jump_cmd, op_flags;
 
 	init_job_desc(desc, 0);
 
+	op_flags = OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG |
+			(handle << OP_ALG_AAI_SHIFT) | OP_ALG_AS_INIT;
+
 	/* INIT RNG in non-test mode */
-	append_operation(desc, OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG |
-			 OP_ALG_AS_INIT);
+	append_operation(desc, op_flags);
+
+	if (!handle && do_sk) {
+		/*
+		 * For SH0, Secure Keys must be generated as well
+		 */
+
+		/* wait for done */
+		jump_cmd = append_jump(desc, JUMP_CLASS_CLASS1);
+		set_jump_tgt_here(desc, jump_cmd);
+
+		/*
+		 * load 1 to clear written reg:
+		 * resets the done interrrupt and returns the RNG to idle.
+		 */
+		append_load_imm_u32(desc, 1, LDST_SRCDST_WORD_CLRW);
+
+		/* Initialize State Handle  */
+		append_operation(desc, OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG |
+				 OP_ALG_AAI_RNG4_SK);
+	}
 
-	/* wait for done */
-	jump_cmd = append_jump(desc, JUMP_CLASS_CLASS1);
-	set_jump_tgt_here(desc, jump_cmd);
+	append_jump(desc, JUMP_CLASS_CLASS1 | JUMP_TYPE_HALT);
+}
 
-	/*
-	 * load 1 to clear written reg:
-	 * resets the done interrupt and returns the RNG to idle.
-	 */
-	append_load_imm_u32(desc, 1, LDST_SRCDST_WORD_CLRW);
+/* Descriptor for deinstantiation of State Handle 0 of the RNG block. */
+static void build_deinstantiation_desc(u32 *desc, int handle)
+{
+	init_job_desc(desc, 0);
 
-	/* generate secure keys (non-test) */
+	/* Uninstantiate State Handle 0 */
 	append_operation(desc, OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG |
-			 OP_ALG_RNG4_SK);
+			 (handle << OP_ALG_AAI_SHIFT) | OP_ALG_AS_INITFINAL);
+
+	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
+ * @status - descriptor status, after being run
+ *
+ * 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,
+					u32 *status)
 {
 	struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev);
 	struct caam_full __iomem *topregs;
 	unsigned int timeout = 100000;
-	u32 *desc;
-	int i, ret = 0;
-
-	desc = kmalloc(CAAM_CMD_SZ * 6, GFP_KERNEL | GFP_DMA);
-	if (!desc) {
-		dev_err(ctrldev, "can't allocate RNG init descriptor memory\n");
-		return -ENOMEM;
-	}
-	build_instantiation_desc(desc);
+	u32 deco_dbg_reg, flags;
+	int i;
 
 	/* Set the bit to request direct access to DECO0 */
 	topregs = (struct caam_full __iomem *)ctrlpriv->ctrl;
@@ -103,36 +96,219 @@ 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));
+
+	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;
 
-	wr_reg32(&topregs->deco.jr_ctl_hi, DECO_JQCR_WHL | DECO_JQCR_FOUR);
+	/* Instruct the DECO to execute it */
+	wr_reg32(&topregs->deco.jr_ctl_hi, flags);
 
 	timeout = 10000000;
-	while ((rd_reg32(&topregs->deco.desc_dbg) & DECO_DBG_VALID) &&
-								 --timeout)
+	do {
+		deco_dbg_reg = rd_reg32(&topregs->deco.desc_dbg);
+		/*
+		 * If an error occured in the descriptor, then
+		 * the DECO status field will be set to 0x0D
+		 */
+		if ((deco_dbg_reg & DESC_DBG_DECO_STAT_MASK) ==
+		    DESC_DBG_DECO_STAT_HOST_ERR)
+			break;
 		cpu_relax();
+	} while ((deco_dbg_reg & DESC_DBG_DECO_STAT_VALID) && --timeout);
 
-	if (!timeout) {
-		dev_err(ctrldev, "failed to instantiate RNG\n");
-		ret = -EIO;
-	}
+	*status = rd_reg32(&topregs->deco.op_status_hi) &
+		  DECO_OP_STATUS_HI_ERR_MASK;
 
+	/* 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
+ * @state_handle_mask - bitmask containing the instantiation status
+ *			for the RNG4 state handles which exist in
+ *			the RNG4 block: 1 if it's been instantiated
+ *			by an external entry, 0 otherwise.
+ * @gen_sk  - generate data to be loaded into the JDKEK, TDKEK and TDSK;
+ *	      Caution: this can be done only once; if the keys need to be
+ *	      regenerated, a POR is required
+ *
+ * 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, int state_handle_mask,
+			   int gen_sk)
+{
+	struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev);
+	struct caam_full __iomem *topregs;
+	struct rng4tst __iomem *r4tst;
+	u32 *desc, status, rdsta_val;
+	int ret = 0, sh_idx;
+
+	topregs = (struct caam_full __iomem *)ctrlpriv->ctrl;
+	r4tst = &topregs->ctrl.r4tst[0];
+
+	desc = kmalloc(CAAM_CMD_SZ * 7, GFP_KERNEL);
+	if (!desc)
+		return -ENOMEM;
+
+	for (sh_idx = 0; sh_idx < RNG4_MAX_HANDLES; sh_idx++) {
+		/*
+		 * If the corresponding bit is set, this state handle
+		 * was initialized by somebody else, so it's left alone.
+		 */
+		if ((1 << sh_idx) & state_handle_mask)
+			continue;
+
+		/* Create the descriptor for instantiating RNG State Handle */
+		build_instantiation_desc(desc, sh_idx, gen_sk);
+
+		/* Try to run it through DECO0 */
+		ret = run_descriptor_deco0(ctrldev, desc, &status);
+
+		/*
+		 * If ret is not 0, or descriptor status is not 0, then
+		 * something went wrong. No need to try the next state
+		 * handle (if available), bail out here.
+		 * Also, if for some reason, the State Handle didn't get
+		 * instantiated although the descriptor has finished
+		 * without any error (HW optimizations for later
+		 * CAAM eras), then try again.
+		 */
+		rdsta_val =
+			rd_reg32(&topregs->ctrl.r4tst[0].rdsta) & RDSTA_IFMASK;
+		if (status || !(rdsta_val & (1 << sh_idx)))
+			ret = -EAGAIN;
+		if (ret)
+			break;
+
+		dev_info(ctrldev, "Instantiated RNG4 SH%d\n", sh_idx);
+		/* Clear the contents before recreating the descriptor */
+		memset(desc, 0x00, CAAM_CMD_SZ * 7);
+	}
+
 	kfree(desc);
+
 	return ret;
 }
 
 /*
- * By default, the TRNG runs for 200 clocks per sample;
- * 1600 clocks per sample generates better entropy.
+ * deinstantiate_rng - builds and executes a descriptor on DECO0,
+ *		       which deinitializes the RNG block.
+ * @ctrldev - pointer to device
+ * @state_handle_mask - bitmask containing the instantiation status
+ *			for the RNG4 state handles which exist in
+ *			the RNG4 block: 1 if it's been instantiated
+ *
+ * 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
  */
-static void kick_trng(struct platform_device *pdev)
+static int deinstantiate_rng(struct device *ctrldev, int state_handle_mask)
+{
+	u32 *desc, status;
+	int sh_idx, ret = 0;
+
+	desc = kmalloc(CAAM_CMD_SZ * 3, GFP_KERNEL);
+	if (!desc)
+		return -ENOMEM;
+
+	for (sh_idx = 0; sh_idx < RNG4_MAX_HANDLES; sh_idx++) {
+		/*
+		 * If the corresponding bit is set, then it means the state
+		 * handle was initialized by us, and thus it needs to be
+		 * deintialized as well
+		 */
+		if ((1 << sh_idx) & state_handle_mask) {
+			/*
+			 * Create the descriptor for deinstantating this state
+			 * handle
+			 */
+			build_deinstantiation_desc(desc, sh_idx);
+
+			/* Try to run it through DECO0 */
+			ret = run_descriptor_deco0(ctrldev, desc, &status);
+
+			if (ret || status) {
+				dev_err(ctrldev,
+					"Failed to deinstantiate RNG4 SH%d\n",
+					sh_idx);
+				break;
+			}
+			dev_info(ctrldev, "Deinstantiated RNG4 SH%d\n", sh_idx);
+		}
+	}
+
+	kfree(desc);
+
+	return ret;
+}
+
+static int caam_remove(struct platform_device *pdev)
+{
+	struct device *ctrldev;
+	struct caam_drv_private *ctrlpriv;
+	struct caam_full __iomem *topregs;
+	int ring, ret = 0;
+
+	ctrldev = &pdev->dev;
+	ctrlpriv = dev_get_drvdata(ctrldev);
+	topregs = (struct caam_full __iomem *)ctrlpriv->ctrl;
+
+	/* Remove platform devices for JobRs */
+	for (ring = 0; ring < ctrlpriv->total_jobrs; ring++) {
+		if (ctrlpriv->jrpdev[ring])
+			of_device_unregister(ctrlpriv->jrpdev[ring]);
+	}
+
+	/* De-initialize RNG state handles initialized by this driver. */
+	if (ctrlpriv->rng4_sh_init)
+		deinstantiate_rng(ctrldev, ctrlpriv->rng4_sh_init);
+
+	/* Shut down debug views */
+#ifdef CONFIG_DEBUG_FS
+	debugfs_remove_recursive(ctrlpriv->dfs_root);
+#endif
+
+	/* Unmap controller region */
+	iounmap(&topregs->ctrl);
+
+	kfree(ctrlpriv->jrpdev);
+	kfree(ctrlpriv);
+
+	return ret;
+}
+
+/*
+ * kick_trng - sets the various parameters for enabling the initialization
+ *	       of the RNG4 block in CAAM
+ * @pdev - pointer to the platform device
+ * @ent_delay - Defines the length (in system clocks) of each entropy sample.
+ */
+static void kick_trng(struct platform_device *pdev, int ent_delay)
 {
 	struct device *ctrldev = &pdev->dev;
 	struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev);
@@ -145,14 +321,31 @@ static void kick_trng(struct platform_device *pdev)
 
 	/* put RNG4 into program mode */
 	setbits32(&r4tst->rtmctl, RTMCTL_PRGM);
-	/* 1600 clocks per sample */
+
+	/*
+	 * Performance-wise, it does not make sense to
+	 * set the delay to a value that is lower
+	 * than the last one that worked (i.e. the state handles
+	 * were instantiated properly. Thus, instead of wasting
+	 * time trying to set the values controlling the sample
+	 * frequency, the function simply returns.
+	 */
+	val = (rd_reg32(&r4tst->rtsdctl) & RTSDCTL_ENT_DLY_MASK)
+	      >> RTSDCTL_ENT_DLY_SHIFT;
+	if (ent_delay <= val) {
+		/* put RNG4 into run mode */
+		clrbits32(&r4tst->rtmctl, RTMCTL_PRGM);
+		return;
+	}
+
 	val = rd_reg32(&r4tst->rtsdctl);
-	val = (val & ~RTSDCTL_ENT_DLY_MASK) | (1600 << RTSDCTL_ENT_DLY_SHIFT);
+	val = (val & ~RTSDCTL_ENT_DLY_MASK) |
+	      (ent_delay << RTSDCTL_ENT_DLY_SHIFT);
 	wr_reg32(&r4tst->rtsdctl, val);
-	/* min. freq. count */
-	wr_reg32(&r4tst->rtfrqmin, 400);
-	/* max. freq. count */
-	wr_reg32(&r4tst->rtfrqmax, 6400);
+	/* min. freq. count, equal to 1/4 of the entropy sample length */
+	wr_reg32(&r4tst->rtfrqmin, ent_delay >> 2);
+	/* max. freq. count, equal to 8 times the entropy sample length */
+	wr_reg32(&r4tst->rtfrqmax, ent_delay << 3);
 	/* put RNG4 into run mode */
 	clrbits32(&r4tst->rtmctl, RTMCTL_PRGM);
 }
@@ -193,7 +386,7 @@ EXPORT_SYMBOL(caam_get_era);
 /* Probe routine for CAAM top (controller) level */
 static int caam_probe(struct platform_device *pdev)
 {
-	int ret, ring, rspec;
+	int ret, ring, rspec, gen_sk, ent_delay = RTSDCTL_ENT_DLY_MIN;
 	u64 caam_id;
 	struct device *dev;
 	struct device_node *nprop, *np;
@@ -258,8 +451,9 @@ static int caam_probe(struct platform_device *pdev)
 			rspec++;
 	}
 
-	ctrlpriv->jrdev = kzalloc(sizeof(struct device *) * rspec, GFP_KERNEL);
-	if (ctrlpriv->jrdev == NULL) {
+	ctrlpriv->jrpdev = kzalloc(sizeof(struct platform_device *) * rspec,
+								GFP_KERNEL);
+	if (ctrlpriv->jrpdev == NULL) {
 		iounmap(&topregs->ctrl);
 		return -ENOMEM;
 	}
@@ -267,13 +461,24 @@ static int caam_probe(struct platform_device *pdev)
 	ring = 0;
 	ctrlpriv->total_jobrs = 0;
 	for_each_compatible_node(np, NULL, "fsl,sec-v4.0-job-ring") {
-		caam_jr_probe(pdev, np, ring);
+		ctrlpriv->jrpdev[ring] =
+				of_platform_device_create(np, NULL, dev);
+		if (!ctrlpriv->jrpdev[ring]) {
+			pr_warn("JR%d Platform device creation error\n", ring);
+			continue;
+		}
 		ctrlpriv->total_jobrs++;
 		ring++;
 	}
 	if (!ring) {
 		for_each_compatible_node(np, NULL, "fsl,sec4.0-job-ring") {
-			caam_jr_probe(pdev, np, ring);
+			ctrlpriv->jrpdev[ring] =
+				of_platform_device_create(np, NULL, dev);
+			if (!ctrlpriv->jrpdev[ring]) {
+				pr_warn("JR%d Platform device creation error\n",
+					ring);
+				continue;
+			}
 			ctrlpriv->total_jobrs++;
 			ring++;
 		}
@@ -299,16 +504,55 @@ static int caam_probe(struct platform_device *pdev)
 
 	/*
 	 * If SEC has RNG version >= 4 and RNG state handle has not been
-	 * already instantiated ,do RNG instantiation
+	 * already instantiated, do RNG instantiation
 	 */
-	if ((cha_vid & CHA_ID_RNG_MASK) >> CHA_ID_RNG_SHIFT >= 4 &&
-	    !(rd_reg32(&topregs->ctrl.r4tst[0].rdsta) & RDSTA_IF0)) {
-		kick_trng(pdev);
-		ret = instantiate_rng(dev);
+	if ((cha_vid & CHA_ID_RNG_MASK) >> CHA_ID_RNG_SHIFT >= 4) {
+		ctrlpriv->rng4_sh_init =
+			rd_reg32(&topregs->ctrl.r4tst[0].rdsta);
+		/*
+		 * If the secure keys (TDKEK, JDKEK, TDSK), were already
+		 * generated, signal this to the function that is instantiating
+		 * the state handles. An error would occur if RNG4 attempts
+		 * to regenerate these keys before the next POR.
+		 */
+		gen_sk = ctrlpriv->rng4_sh_init & RDSTA_SKVN ? 0 : 1;
+		ctrlpriv->rng4_sh_init &= RDSTA_IFMASK;
+		do {
+			int inst_handles =
+				rd_reg32(&topregs->ctrl.r4tst[0].rdsta) &
+								RDSTA_IFMASK;
+			/*
+			 * If either SH were instantiated by somebody else
+			 * (e.g. u-boot) then it is assumed that the entropy
+			 * parameters are properly set and thus the function
+			 * setting these (kick_trng(...)) is skipped.
+			 * Also, if a handle was instantiated, do not change
+			 * the TRNG parameters.
+			 */
+			if (!(ctrlpriv->rng4_sh_init || inst_handles)) {
+				kick_trng(pdev, ent_delay);
+				ent_delay += 400;
+			}
+			/*
+			 * if instantiate_rng(...) fails, the loop will rerun
+			 * and the kick_trng(...) function will modfiy the
+			 * upper and lower limits of the entropy sampling
+			 * interval, leading to a sucessful initialization of
+			 * the RNG.
+			 */
+			ret = instantiate_rng(dev, inst_handles,
+					      gen_sk);
+		} while ((ret == -EAGAIN) && (ent_delay < RTSDCTL_ENT_DLY_MAX));
 		if (ret) {
+			dev_err(dev, "failed to instantiate RNG");
 			caam_remove(pdev);
 			return ret;
 		}
+		/*
+		 * Set handles init'ed by this module as the complement of the
+		 * already initialized ones
+		 */
+		ctrlpriv->rng4_sh_init = ~ctrlpriv->rng4_sh_init & RDSTA_IFMASK;
 
 		/* Enable RDB bit so that RNG works faster */
 		setbits32(&topregs->ctrl.scfgr, SCFGR_RDBENABLE);