crypto: caam - add power management support

Add support for suspend and resume operation for PM in CAAM driver.

When the CAAM goes in suspend, the hardware is considered to do nothing.

On some platforms, the power of the CAAM is not turned off so it keeps
its configuration.
On other platforms, it doesn't so it is necessary to save the state of
the CAAM:
 - JRs MID
 - Address of input and output rings

Signed-off-by: Horia Geanta <horia.geanta@nxp.com>
Signed-off-by: Victoria Milhoan <vicki.milhoan@freescale.com>
Signed-off-by: Dan Douglass <dan.douglass@nxp.com>
Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
Signed-off-by: Franck LENORMAND <franck.lenormand@nxp.com>
Signed-off-by: Meenakshi Aggarwal <meenakshi.aggarwal@nxp.com>
Reviewed-by: Gaurav Jain <gaurav.jain@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 175 insertions, 18 deletions

diff --git a/drivers/crypto/caam/jr.c b/drivers/crypto/caam/jr.c
index 96dea5304d22..316180d26f8a 100644
--- a/drivers/crypto/caam/jr.c
+++ b/drivers/crypto/caam/jr.c
@@ -117,6 +117,23 @@ static int caam_jr_flush(struct device *dev)
 	return caam_jr_stop_processing(dev, JRCR_RESET);
 }
 
+/* The resume can be used after a park or a flush if CAAM has not been reset */
+static int caam_jr_restart_processing(struct device *dev)
+{
+	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
+	u32 halt_status = rd_reg32(&jrp->rregs->jrintstatus) &
+			  JRINT_ERR_HALT_MASK;
+
+	/* Check that the flush/park is completed */
+	if (halt_status != JRINT_ERR_HALT_COMPLETE)
+		return -1;
+
+	/* Resume processing of jobs */
+	clrsetbits_32(&jrp->rregs->jrintstatus, 0, JRINT_ERR_HALT_COMPLETE);
+
+	return 0;
+}
+
 static int caam_reset_hw_jr(struct device *dev)
 {
 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
@@ -245,7 +262,8 @@ static irqreturn_t caam_jr_interrupt(int irq, void *st_dev)
 static void caam_jr_dequeue(unsigned long devarg)
 {
 	int hw_idx, sw_idx, i, head, tail;
-	struct device *dev = (struct device *)devarg;
+	struct caam_jr_dequeue_params *params = (void *)devarg;
+	struct device *dev = params->dev;
 	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
 	void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg);
 	u32 *userdesc, userstatus;
@@ -319,8 +337,9 @@ static void caam_jr_dequeue(unsigned long devarg)
 		outring_used--;
 	}
 
-	/* reenable / unmask IRQs */
-	clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
+	if (params->enable_itr)
+		/* reenable / unmask IRQs */
+		clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0);
 }
 
 /**
@@ -470,6 +489,29 @@ int caam_jr_enqueue(struct device *dev, u32 *desc,
 }
 EXPORT_SYMBOL(caam_jr_enqueue);
 
+static void caam_jr_init_hw(struct device *dev, dma_addr_t inpbusaddr,
+			    dma_addr_t outbusaddr)
+{
+	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
+
+	wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
+	wr_reg64(&jrp->rregs->outring_base, outbusaddr);
+	wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
+	wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
+
+	/* Select interrupt coalescing parameters */
+	clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JOBR_INTC |
+		      (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
+		      (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
+}
+
+static void caam_jr_reset_index(struct caam_drv_private_jr *jrp)
+{
+	jrp->out_ring_read_index = 0;
+	jrp->head = 0;
+	jrp->tail = 0;
+}
+
 /*
  * Init JobR independent of platform property detection
  */
@@ -506,25 +548,16 @@ static int caam_jr_init(struct device *dev)
 		jrp->entinfo[i].desc_addr_dma = !0;
 
 	/* Setup rings */
-	jrp->out_ring_read_index = 0;
-	jrp->head = 0;
-	jrp->tail = 0;
-
-	wr_reg64(&jrp->rregs->inpring_base, inpbusaddr);
-	wr_reg64(&jrp->rregs->outring_base, outbusaddr);
-	wr_reg32(&jrp->rregs->inpring_size, JOBR_DEPTH);
-	wr_reg32(&jrp->rregs->outring_size, JOBR_DEPTH);
-
+	caam_jr_reset_index(jrp);
 	jrp->inpring_avail = JOBR_DEPTH;
+	caam_jr_init_hw(dev, inpbusaddr, outbusaddr);
 
 	spin_lock_init(&jrp->inplock);
 
-	/* Select interrupt coalescing parameters */
-	clrsetbits_32(&jrp->rregs->rconfig_lo, 0, JOBR_INTC |
-		      (JOBR_INTC_COUNT_THLD << JRCFG_ICDCT_SHIFT) |
-		      (JOBR_INTC_TIME_THLD << JRCFG_ICTT_SHIFT));
-
-	tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev);
+	jrp->tasklet_params.dev = dev;
+	jrp->tasklet_params.enable_itr = 1;
+	tasklet_init(&jrp->irqtask, caam_jr_dequeue,
+		     (unsigned long)&jrp->tasklet_params);
 
 	/* Connect job ring interrupt handler. */
 	error = devm_request_irq(dev, jrp->irq, caam_jr_interrupt, IRQF_SHARED,
@@ -635,11 +668,134 @@ static int caam_jr_probe(struct platform_device *pdev)
 
 	atomic_set(&jrpriv->tfm_count, 0);
 
+	device_init_wakeup(&pdev->dev, 1);
+	device_set_wakeup_enable(&pdev->dev, false);
+
 	register_algs(jrpriv, jrdev->parent);
 
 	return 0;
 }
 
+static void caam_jr_get_hw_state(struct device *dev)
+{
+	struct caam_drv_private_jr *jrp = dev_get_drvdata(dev);
+
+	jrp->state.inpbusaddr = rd_reg64(&jrp->rregs->inpring_base);
+	jrp->state.outbusaddr = rd_reg64(&jrp->rregs->outring_base);
+}
+
+static int caam_jr_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct caam_drv_private_jr *jrpriv = platform_get_drvdata(pdev);
+	struct caam_drv_private *ctrlpriv = dev_get_drvdata(dev->parent);
+	struct caam_jr_dequeue_params suspend_params = {
+		.dev = dev,
+		.enable_itr = 0,
+	};
+
+	/* Remove the node from Physical JobR list maintained by driver */
+	spin_lock(&driver_data.jr_alloc_lock);
+	list_del(&jrpriv->list_node);
+	spin_unlock(&driver_data.jr_alloc_lock);
+
+	if (jrpriv->hwrng)
+		caam_rng_exit(dev->parent);
+
+	if (ctrlpriv->caam_off_during_pm) {
+		int err;
+
+		tasklet_disable(&jrpriv->irqtask);
+
+		/* mask itr to call flush */
+		clrsetbits_32(&jrpriv->rregs->rconfig_lo, 0, JRCFG_IMSK);
+
+		/* Invalid job in process */
+		err = caam_jr_flush(dev);
+		if (err) {
+			dev_err(dev, "Failed to flush\n");
+			return err;
+		}
+
+		/* Dequeing jobs flushed */
+		caam_jr_dequeue((unsigned long)&suspend_params);
+
+		/* Save state */
+		caam_jr_get_hw_state(dev);
+	} else if (device_may_wakeup(&pdev->dev)) {
+		enable_irq_wake(jrpriv->irq);
+	}
+
+	return 0;
+}
+
+static int caam_jr_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct caam_drv_private_jr *jrpriv = platform_get_drvdata(pdev);
+	struct caam_drv_private *ctrlpriv = dev_get_drvdata(dev->parent);
+
+	if (ctrlpriv->caam_off_during_pm) {
+		u64 inp_addr;
+		int err;
+
+		/*
+		 * Check if the CAAM has been resetted checking the address of
+		 * the input ring
+		 */
+		inp_addr = rd_reg64(&jrpriv->rregs->inpring_base);
+		if (inp_addr != 0) {
+			/* JR still has some configuration */
+			if (inp_addr == jrpriv->state.inpbusaddr) {
+				/* JR has not been resetted */
+				err = caam_jr_restart_processing(dev);
+				if (err) {
+					dev_err(dev,
+						"Restart processing failed\n");
+					return err;
+				}
+
+				tasklet_enable(&jrpriv->irqtask);
+
+				clrsetbits_32(&jrpriv->rregs->rconfig_lo,
+					      JRCFG_IMSK, 0);
+
+				goto add_jr;
+			} else if (ctrlpriv->optee_en) {
+				/* JR has been used by OPTEE, reset it */
+				err = caam_reset_hw_jr(dev);
+				if (err) {
+					dev_err(dev, "Failed to reset JR\n");
+					return err;
+				}
+			} else {
+				/* No explanation, return error */
+				return -EIO;
+			}
+		}
+
+		caam_jr_reset_index(jrpriv);
+		caam_jr_init_hw(dev, jrpriv->state.inpbusaddr,
+				jrpriv->state.outbusaddr);
+
+		tasklet_enable(&jrpriv->irqtask);
+	} else if (device_may_wakeup(&pdev->dev)) {
+		disable_irq_wake(jrpriv->irq);
+	}
+
+add_jr:
+	spin_lock(&driver_data.jr_alloc_lock);
+	list_add_tail(&jrpriv->list_node, &driver_data.jr_list);
+	spin_unlock(&driver_data.jr_alloc_lock);
+
+	if (jrpriv->hwrng)
+		jrpriv->hwrng = !caam_rng_init(dev->parent);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(caam_jr_pm_ops, caam_jr_suspend, caam_jr_resume);
+
 static const struct of_device_id caam_jr_match[] = {
 	{
 		.compatible = "fsl,sec-v4.0-job-ring",
@@ -655,6 +811,7 @@ static struct platform_driver caam_jr_driver = {
 	.driver = {
 		.name = "caam_jr",
 		.of_match_table = caam_jr_match,
+		.pm = &caam_jr_pm_ops,
 	},
 	.probe       = caam_jr_probe,
 	.remove      = caam_jr_remove,