crypto: caam - Add API's to allocate/free Job Rings

With each of the Job Ring available as a platform device, the
Job Ring driver needs to take care of allocation/deallocation
of the Job Rings to the above interface layers. Added APIs
in Job Ring Driver to allocate/free Job rings

Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Reviewed-by: Garg Vakul-B16394 <vakul@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/caam/intern.h b/drivers/crypto/caam/intern.h
index bff4acd3882d17ef12d7049f8c5ecbe8f2348f25..b781445d2fcca267704aef26e94623b2690301c5 100644 (file)
--- a/drivers/crypto/caam/intern.h
+++ b/drivers/crypto/caam/intern.h
@@ -44,6 +44,9 @@ struct caam_drv_private_jr {
        struct tasklet_struct irqtask;
        int irq;                        /* One per queue */
 
+       /* Number of scatterlist crypt transforms active on the JobR */
+       atomic_t tfm_count ____cacheline_aligned;
+
        /* Job ring info */
        int ringsize;   /* Size of rings (assume input = output) */
        struct caam_jrentry_info *entinfo;      /* Alloc'ed 1 per ring entry */

diff --git a/drivers/crypto/caam/jr.c b/drivers/crypto/caam/jr.c
index cdeaf2519b485d4ad2723d274eb93f5978ac4d8e..636bb53125abb4ec9b2db615dd130c02cec3ada7 100644 (file)
--- a/drivers/crypto/caam/jr.c
+++ b/drivers/crypto/caam/jr.c
@@ -97,10 +97,9 @@ static int caam_jr_remove(struct platform_device *pdev)
        jrpriv = dev_get_drvdata(jrdev);
 
        /*
-        * Make sure ring is empty before release
+        * Return EBUSY if job ring already allocated.
         */
-       if (rd_reg32(&jrpriv->rregs->outring_used) ||
-           (rd_reg32(&jrpriv->rregs->inpring_avail) != JOBR_DEPTH)) {
+       if (atomic_read(&jrpriv->tfm_count)) {
                dev_err(jrdev, "Device is busy\n");
                return -EBUSY;
        }
@@ -233,6 +232,59 @@ static void caam_jr_dequeue(unsigned long devarg)
        clrbits32(&jrp->rregs->rconfig_lo, JRCFG_IMSK);
 }
 
+/**
+ * caam_jr_alloc() - Alloc a job ring for someone to use as needed.
+ *
+ * returns :  pointer to the newly allocated physical
+ *           JobR dev can be written to if successful.
+ **/
+struct device *caam_jr_alloc(void)
+{
+       struct caam_drv_private_jr *jrpriv, *min_jrpriv = NULL;
+       struct device *dev = NULL;
+       int min_tfm_cnt = INT_MAX;
+       int tfm_cnt;
+
+       spin_lock(&driver_data.jr_alloc_lock);
+
+       if (list_empty(&driver_data.jr_list)) {
+               spin_unlock(&driver_data.jr_alloc_lock);
+               return ERR_PTR(-ENODEV);
+       }
+
+       list_for_each_entry(jrpriv, &driver_data.jr_list, list_node) {
+               tfm_cnt = atomic_read(&jrpriv->tfm_count);
+               if (tfm_cnt < min_tfm_cnt) {
+                       min_tfm_cnt = tfm_cnt;
+                       min_jrpriv = jrpriv;
+               }
+               if (!min_tfm_cnt)
+                       break;
+       }
+
+       if (min_jrpriv) {
+               atomic_inc(&min_jrpriv->tfm_count);
+               dev = min_jrpriv->dev;
+       }
+       spin_unlock(&driver_data.jr_alloc_lock);
+
+       return dev;
+}
+EXPORT_SYMBOL(caam_jr_alloc);
+
+/**
+ * caam_jr_free() - Free the Job Ring
+ * @rdev     - points to the dev that identifies the Job ring to
+ *             be released.
+ **/
+void caam_jr_free(struct device *rdev)
+{
+       struct caam_drv_private_jr *jrpriv = dev_get_drvdata(rdev);
+
+       atomic_dec(&jrpriv->tfm_count);
+}
+EXPORT_SYMBOL(caam_jr_free);
+
 /**
  * caam_jr_enqueue() - Enqueue a job descriptor head. Returns 0 if OK,
  * -EBUSY if the queue is full, -EIO if it cannot map the caller's
@@ -442,6 +494,8 @@ static int caam_jr_probe(struct platform_device *pdev)
        list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
        spin_unlock(&driver_data.jr_alloc_lock);
 
+       atomic_set(&jrpriv->tfm_count, 0);
+
        return 0;
 }
 

diff --git a/drivers/crypto/caam/jr.h b/drivers/crypto/caam/jr.h
index 02f69bbbab084c796bd2ccd6fc9f789fdf700381..97113a6d6c58f500cd7aeb64a4d506ebfc0ca688 100644 (file)
--- a/drivers/crypto/caam/jr.h
+++ b/drivers/crypto/caam/jr.h
@@ -8,6 +8,8 @@
 #define JR_H
 
 /* Prototypes for backend-level services exposed to APIs */
+struct device *caam_jr_alloc(void);
+void caam_jr_free(struct device *rdev);
 int caam_jr_enqueue(struct device *dev, u32 *desc,
                    void (*cbk)(struct device *dev, u32 *desc, u32 status,
                                void *areq),