1 files changed, 331 insertions, 87 deletions

diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c
index bc6d820812b6..63fb1af2c431 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);