3 files changed, 71 insertions, 3 deletions

diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index e7cc54268f2f..baee2bc1e8a8 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -686,6 +686,8 @@ struct dwc2_hregs_backup {
  * @frame_list:         Frame list
  * @frame_list_dma:     Frame list DMA address
  * @frame_list_sz:      Frame list size
+ * @desc_gen_cache:     Kmem cache for generic descriptors
+ * @desc_hsisoc_cache:  Kmem cache for hs isochronous descriptors
  *
  * These are for peripheral mode:
  *
@@ -806,6 +808,8 @@ struct dwc2_hsotg {
 	u32 *frame_list;
 	dma_addr_t frame_list_dma;
 	u32 frame_list_sz;
+	struct kmem_cache *desc_gen_cache;
+	struct kmem_cache *desc_hsisoc_cache;
 
 #ifdef DEBUG
 	u32 frrem_samples;
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index 7fd4f41e12a7..b2afe913d559 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -3146,6 +3146,47 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg, int irq)
 	if (!hsotg->status_buf)
 		goto error3;
 
+	/*
+	 * Create kmem caches to handle descriptor buffers in descriptor
+	 * DMA mode.
+	 * Alignment must be set to 512 bytes.
+	 */
+	if (hsotg->core_params->dma_desc_enable ||
+	    hsotg->core_params->dma_desc_fs_enable) {
+		hsotg->desc_gen_cache = kmem_cache_create("dwc2-gen-desc",
+				sizeof(struct dwc2_hcd_dma_desc) *
+				MAX_DMA_DESC_NUM_GENERIC, 512, SLAB_CACHE_DMA,
+				NULL);
+		if (!hsotg->desc_gen_cache) {
+			dev_err(hsotg->dev,
+				"unable to create dwc2 generic desc cache\n");
+
+			/*
+			 * Disable descriptor dma mode since it will not be
+			 * usable.
+			 */
+			hsotg->core_params->dma_desc_enable = 0;
+			hsotg->core_params->dma_desc_fs_enable = 0;
+		}
+
+		hsotg->desc_hsisoc_cache = kmem_cache_create("dwc2-hsisoc-desc",
+				sizeof(struct dwc2_hcd_dma_desc) *
+				MAX_DMA_DESC_NUM_HS_ISOC, 512, 0, NULL);
+		if (!hsotg->desc_hsisoc_cache) {
+			dev_err(hsotg->dev,
+				"unable to create dwc2 hs isoc desc cache\n");
+
+			kmem_cache_destroy(hsotg->desc_gen_cache);
+
+			/*
+			 * Disable descriptor dma mode since it will not be
+			 * usable.
+			 */
+			hsotg->core_params->dma_desc_enable = 0;
+			hsotg->core_params->dma_desc_fs_enable = 0;
+		}
+	}
+
 	hsotg->otg_port = 1;
 	hsotg->frame_list = NULL;
 	hsotg->frame_list_dma = 0;
@@ -3169,7 +3210,7 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg, int irq)
 	 */
 	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 	if (retval < 0)
-		goto error3;
+		goto error4;
 
 	device_wakeup_enable(hcd->self.controller);
 
@@ -3179,6 +3220,9 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg, int irq)
 
 	return 0;
 
+error4:
+	kmem_cache_destroy(hsotg->desc_gen_cache);
+	kmem_cache_destroy(hsotg->desc_hsisoc_cache);
 error3:
 	dwc2_hcd_release(hsotg);
 error2:
@@ -3219,6 +3263,10 @@ void dwc2_hcd_remove(struct dwc2_hsotg *hsotg)
 
 	usb_remove_hcd(hcd);
 	hsotg->priv = NULL;
+
+	kmem_cache_destroy(hsotg->desc_gen_cache);
+	kmem_cache_destroy(hsotg->desc_hsisoc_cache);
+
 	dwc2_hcd_release(hsotg);
 	usb_put_hcd(hcd);
 
diff --git a/drivers/usb/dwc2/hcd_ddma.c b/drivers/usb/dwc2/hcd_ddma.c
index 85d7816d29f1..36606fc33c0d 100644
--- a/drivers/usb/dwc2/hcd_ddma.c
+++ b/drivers/usb/dwc2/hcd_ddma.c
@@ -87,10 +87,18 @@ static u16 dwc2_frame_incr_val(struct dwc2_qh *qh)
 static int dwc2_desc_list_alloc(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
 				gfp_t flags)
 {
+	struct kmem_cache *desc_cache;
+
+	if (qh->ep_type == USB_ENDPOINT_XFER_ISOC
+	    && qh->dev_speed == USB_SPEED_HIGH)
+		desc_cache = hsotg->desc_hsisoc_cache;
+	else
+		desc_cache = hsotg->desc_gen_cache;
+
 	qh->desc_list_sz = sizeof(struct dwc2_hcd_dma_desc) *
 						dwc2_max_desc_num(qh);
 
-	qh->desc_list = kzalloc(qh->desc_list_sz, flags | GFP_DMA);
+	qh->desc_list = kmem_cache_zalloc(desc_cache, flags | GFP_DMA);
 	if (!qh->desc_list)
 		return -ENOMEM;
 
@@ -113,10 +121,18 @@ static int dwc2_desc_list_alloc(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
 
 static void dwc2_desc_list_free(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
 {
+	struct kmem_cache *desc_cache;
+
+	if (qh->ep_type == USB_ENDPOINT_XFER_ISOC
+	    && qh->dev_speed == USB_SPEED_HIGH)
+		desc_cache = hsotg->desc_hsisoc_cache;
+	else
+		desc_cache = hsotg->desc_gen_cache;
+
 	if (qh->desc_list) {
 		dma_unmap_single(hsotg->dev, qh->desc_list_dma,
 				 qh->desc_list_sz, DMA_FROM_DEVICE);
-		kfree(qh->desc_list);
+		kmem_cache_free(desc_cache, qh->desc_list);
 		qh->desc_list = NULL;
 	}