crypto: caam - RNG instantiation by directly programming DECO

Remove the dependency of RNG instantiation on Job Ring. Now
RNG instantiation for devices with RNG version > 4 is done
by directly programming DECO 0.

Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

2 files changed, 47 insertions, 39 deletions

diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c
index f5d6deced1cb..86c96009faad 100644
--- a/drivers/crypto/caam/ctrl.c
+++ b/drivers/crypto/caam/ctrl.c
@@ -75,55 +75,53 @@ static void build_instantiation_desc(u32 *desc)
                          OP_ALG_RNG4_SK);
 }
 
-struct instantiate_result {
-        struct completion completion;
-        int err;
-};
-
-static void rng4_init_done(struct device *dev, u32 *desc, u32 err,
-                           void *context)
+static int instantiate_rng(struct device *ctrldev)
 {
-        struct instantiate_result *instantiation = context;
-
-        if (err) {
-                char tmp[CAAM_ERROR_STR_MAX];
-
-                dev_err(dev, "%08x: %s\n", err, caam_jr_strstatus(tmp, err));
-        }
-
-        instantiation->err = err;
-        complete(&instantiation->completion);
-}
-
-static int instantiate_rng(struct device *jrdev)
-{
-        struct instantiate_result instantiation;
-
-        dma_addr_t desc_dma;
+        struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev);
+        struct caam_full __iomem *topregs;
+        unsigned int timeout = 100000;
         u32 *desc;
-        int ret;
+        int i, ret = 0;
 
         desc = kmalloc(CAAM_CMD_SZ * 6, GFP_KERNEL | GFP_DMA);
         if (!desc) {
-                dev_err(jrdev, "cannot allocate RNG init descriptor memory\n");
+                dev_err(ctrldev, "can't allocate RNG init descriptor memory\n");
                 return -ENOMEM;
         }
-
         build_instantiation_desc(desc);
-        desc_dma = dma_map_single(jrdev, desc, desc_bytes(desc), DMA_TO_DEVICE);
-        init_completion(&instantiation.completion);
-        ret = caam_jr_enqueue(jrdev, desc, rng4_init_done, &instantiation);
-        if (!ret) {
-                wait_for_completion_interruptible(&instantiation.completion);
-                ret = instantiation.err;
-                if (ret)
-                        dev_err(jrdev, "unable to instantiate RNG\n");
+
+        /* Set the bit to request direct access to DECO0 */
+        topregs = (struct caam_full __iomem *)ctrlpriv->ctrl;
+        setbits32(&topregs->ctrl.deco_rq, DECORR_RQD0ENABLE);
+
+        while (!(rd_reg32(&topregs->ctrl.deco_rq) & DECORR_DEN0) &&
+                                                                 --timeout)
+                cpu_relax();
+
+        if (!timeout) {
+                dev_err(ctrldev, "failed to acquire DECO 0\n");
+                ret = -EIO;
+                goto out;
         }
 
-        dma_unmap_single(jrdev, desc_dma, desc_bytes(desc), DMA_TO_DEVICE);
+        for (i = 0; i < desc_len(desc); i++)
+                topregs->deco.descbuf[i] = *(desc + i);
 
-        kfree(desc);
+        wr_reg32(&topregs->deco.jr_ctl_hi, DECO_JQCR_WHL | DECO_JQCR_FOUR);
+
+        timeout = 10000000;
+        while ((rd_reg32(&topregs->deco.desc_dbg) & DECO_DBG_VALID) &&
+                                                                 --timeout)
+                cpu_relax();
 
+        if (!timeout) {
+                dev_err(ctrldev, "failed to instantiate RNG\n");
+                ret = -EIO;
+        }
+
+        clrbits32(&topregs->ctrl.deco_rq, DECORR_RQD0ENABLE);
+out:
+        kfree(desc);
         return ret;
 }
 
@@ -303,7 +301,7 @@ static int caam_probe(struct platform_device *pdev)
         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(ctrlpriv->jrdev[0]);
+                ret = instantiate_rng(dev);
                 if (ret) {
                         caam_remove(pdev);
                         return ret;
diff --git a/drivers/crypto/caam/regs.h b/drivers/crypto/caam/regs.h
index c09142fc13e3..4455396918de 100644
--- a/drivers/crypto/caam/regs.h
+++ b/drivers/crypto/caam/regs.h
@@ -341,6 +341,8 @@ struct caam_ctrl {
 #define MCFGR_DMA_RESET         0x10000000
 #define MCFGR_LONG_PTR          0x00010000 /* Use >32-bit desc addressing */
 #define SCFGR_RDBENABLE         0x00000400
+#define DECORR_RQD0ENABLE       0x00000001 /* Enable DECO0 for direct access */
+#define DECORR_DEN0             0x00010000 /* DECO0 available for access*/
 
 /* AXI read cache control */
 #define MCFGR_ARCACHE_SHIFT     12
@@ -703,9 +705,16 @@ struct caam_deco {
         struct deco_sg_table sctr_tbl[4];       /* DxSTR - Scatter Tables */
         u32 rsvd29[48];
         u32 descbuf[64];        /* DxDESB - Descriptor buffer */
-        u32 rsvd30[320];
+        u32 rscvd30[193];
+        u32 desc_dbg;           /* DxDDR - DECO Debug Register */
+        u32 rsvd31[126];
 };
 
+/* DECO DBG Register Valid Bit*/
+#define DECO_DBG_VALID          0x80000000
+#define DECO_JQCR_WHL           0x20000000
+#define DECO_JQCR_FOUR          0x10000000
+
 /*
  * Current top-level view of memory map is:
  *
@@ -733,6 +742,7 @@ struct caam_full {
         u64 rsvd[512];
         struct caam_assurance assure;
         struct caam_queue_if qi;
+        struct caam_deco deco;
 };
 
 #endif /* REGS_H */