Adding upstream version 6.8.9.upstream/6.8.9

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 166 insertions, 96 deletions

diff --git a/drivers/bus/mhi/ep/main.c b/drivers/bus/mhi/ep/main.c
index 934cdbca08..65f1f6b9b5 100644
--- a/drivers/bus/mhi/ep/main.c
+++ b/drivers/bus/mhi/ep/main.c
@@ -54,11 +54,27 @@ static int mhi_ep_send_event(struct mhi_ep_cntrl *mhi_cntrl, u32 ring_idx,
 	mutex_unlock(&mhi_cntrl->event_lock);
 
 	/*
-	 * Raise IRQ to host only if the BEI flag is not set in TRE. Host might
-	 * set this flag for interrupt moderation as per MHI protocol.
+	 * As per the MHI specification, section 4.3, Interrupt moderation:
+	 *
+	 * 1. If BEI flag is not set, cancel any pending intmodt work if started
+	 * for the event ring and raise IRQ immediately.
+	 *
+	 * 2. If both BEI and intmodt are set, and if no IRQ is pending for the
+	 * same event ring, start the IRQ delayed work as per the value of
+	 * intmodt. If previous IRQ is pending, then do nothing as the pending
+	 * IRQ is enough for the host to process the current event ring element.
+	 *
+	 * 3. If BEI is set and intmodt is not set, no need to raise IRQ.
 	 */
-	if (!bei)
+	if (!bei) {
+		if (READ_ONCE(ring->irq_pending))
+			cancel_delayed_work(&ring->intmodt_work);
+
 		mhi_cntrl->raise_irq(mhi_cntrl, ring->irq_vector);
+	} else if (ring->intmodt && !READ_ONCE(ring->irq_pending)) {
+		WRITE_ONCE(ring->irq_pending, true);
+		schedule_delayed_work(&ring->intmodt_work, msecs_to_jiffies(ring->intmodt));
+	}
 
 	return 0;
 
@@ -183,6 +199,8 @@ static int mhi_ep_process_cmd_ring(struct mhi_ep_ring *ring, struct mhi_ring_ele
 
 				goto err_unlock;
 			}
+
+			mhi_chan->rd_offset = ch_ring->rd_offset;
 		}
 
 		/* Set channel state to RUNNING */
@@ -312,21 +330,85 @@ bool mhi_ep_queue_is_empty(struct mhi_ep_device *mhi_dev, enum dma_data_directio
 	struct mhi_ep_cntrl *mhi_cntrl = mhi_dev->mhi_cntrl;
 	struct mhi_ep_ring *ring = &mhi_cntrl->mhi_chan[mhi_chan->chan].ring;
 
-	return !!(ring->rd_offset == ring->wr_offset);
+	return !!(mhi_chan->rd_offset == ring->wr_offset);
 }
 EXPORT_SYMBOL_GPL(mhi_ep_queue_is_empty);
 
+static void mhi_ep_read_completion(struct mhi_ep_buf_info *buf_info)
+{
+	struct mhi_ep_device *mhi_dev = buf_info->mhi_dev;
+	struct mhi_ep_cntrl *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct mhi_ep_chan *mhi_chan = mhi_dev->ul_chan;
+	struct mhi_ep_ring *ring = &mhi_cntrl->mhi_chan[mhi_chan->chan].ring;
+	struct mhi_ring_element *el = &ring->ring_cache[ring->rd_offset];
+	struct mhi_result result = {};
+	int ret;
+
+	if (mhi_chan->xfer_cb) {
+		result.buf_addr = buf_info->cb_buf;
+		result.dir = mhi_chan->dir;
+		result.bytes_xferd = buf_info->size;
+
+		mhi_chan->xfer_cb(mhi_dev, &result);
+	}
+
+	/*
+	 * The host will split the data packet into multiple TREs if it can't fit
+	 * the packet in a single TRE. In that case, CHAIN flag will be set by the
+	 * host for all TREs except the last one.
+	 */
+	if (buf_info->code != MHI_EV_CC_OVERFLOW) {
+		if (MHI_TRE_DATA_GET_CHAIN(el)) {
+			/*
+			 * IEOB (Interrupt on End of Block) flag will be set by the host if
+			 * it expects the completion event for all TREs of a TD.
+			 */
+			if (MHI_TRE_DATA_GET_IEOB(el)) {
+				ret = mhi_ep_send_completion_event(mhi_cntrl, ring, el,
+							     MHI_TRE_DATA_GET_LEN(el),
+							     MHI_EV_CC_EOB);
+				if (ret < 0) {
+					dev_err(&mhi_chan->mhi_dev->dev,
+						"Error sending transfer compl. event\n");
+					goto err_free_tre_buf;
+				}
+			}
+		} else {
+			/*
+			 * IEOT (Interrupt on End of Transfer) flag will be set by the host
+			 * for the last TRE of the TD and expects the completion event for
+			 * the same.
+			 */
+			if (MHI_TRE_DATA_GET_IEOT(el)) {
+				ret = mhi_ep_send_completion_event(mhi_cntrl, ring, el,
+							     MHI_TRE_DATA_GET_LEN(el),
+							     MHI_EV_CC_EOT);
+				if (ret < 0) {
+					dev_err(&mhi_chan->mhi_dev->dev,
+						"Error sending transfer compl. event\n");
+					goto err_free_tre_buf;
+				}
+			}
+		}
+	}
+
+	mhi_ep_ring_inc_index(ring);
+
+err_free_tre_buf:
+	kmem_cache_free(mhi_cntrl->tre_buf_cache, buf_info->cb_buf);
+}
+
 static int mhi_ep_read_channel(struct mhi_ep_cntrl *mhi_cntrl,
-				struct mhi_ep_ring *ring,
-				struct mhi_result *result,
-				u32 len)
+			       struct mhi_ep_ring *ring)
 {
 	struct mhi_ep_chan *mhi_chan = &mhi_cntrl->mhi_chan[ring->ch_id];
 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
 	size_t tr_len, read_offset, write_offset;
 	struct mhi_ep_buf_info buf_info = {};
+	u32 len = MHI_EP_DEFAULT_MTU;
 	struct mhi_ring_element *el;
 	bool tr_done = false;
+	void *buf_addr;
 	u32 buf_left;
 	int ret;
 
@@ -339,7 +421,7 @@ static int mhi_ep_read_channel(struct mhi_ep_cntrl *mhi_cntrl,
 			return -ENODEV;
 		}
 
-		el = &ring->ring_cache[ring->rd_offset];
+		el = &ring->ring_cache[mhi_chan->rd_offset];
 
 		/* Check if there is data pending to be read from previous read operation */
 		if (mhi_chan->tre_bytes_left) {
@@ -356,82 +438,50 @@ static int mhi_ep_read_channel(struct mhi_ep_cntrl *mhi_cntrl,
 		read_offset = mhi_chan->tre_size - mhi_chan->tre_bytes_left;
 		write_offset = len - buf_left;
 
+		buf_addr = kmem_cache_zalloc(mhi_cntrl->tre_buf_cache, GFP_KERNEL | GFP_DMA);
+		if (!buf_addr)
+			return -ENOMEM;
+
 		buf_info.host_addr = mhi_chan->tre_loc + read_offset;
-		buf_info.dev_addr = result->buf_addr + write_offset;
+		buf_info.dev_addr = buf_addr + write_offset;
 		buf_info.size = tr_len;
+		buf_info.cb = mhi_ep_read_completion;
+		buf_info.cb_buf = buf_addr;
+		buf_info.mhi_dev = mhi_chan->mhi_dev;
+
+		if (mhi_chan->tre_bytes_left - tr_len)
+			buf_info.code = MHI_EV_CC_OVERFLOW;
 
 		dev_dbg(dev, "Reading %zd bytes from channel (%u)\n", tr_len, ring->ch_id);
-		ret = mhi_cntrl->read_from_host(mhi_cntrl, &buf_info);
+		ret = mhi_cntrl->read_async(mhi_cntrl, &buf_info);
 		if (ret < 0) {
 			dev_err(&mhi_chan->mhi_dev->dev, "Error reading from channel\n");
-			return ret;
+			goto err_free_buf_addr;
 		}
 
 		buf_left -= tr_len;
 		mhi_chan->tre_bytes_left -= tr_len;
 
-		/*
-		 * Once the TRE (Transfer Ring Element) of a TD (Transfer Descriptor) has been
-		 * read completely:
-		 *
-		 * 1. Send completion event to the host based on the flags set in TRE.
-		 * 2. Increment the local read offset of the transfer ring.
-		 */
 		if (!mhi_chan->tre_bytes_left) {
-			/*
-			 * The host will split the data packet into multiple TREs if it can't fit
-			 * the packet in a single TRE. In that case, CHAIN flag will be set by the
-			 * host for all TREs except the last one.
-			 */
-			if (MHI_TRE_DATA_GET_CHAIN(el)) {
-				/*
-				 * IEOB (Interrupt on End of Block) flag will be set by the host if
-				 * it expects the completion event for all TREs of a TD.
-				 */
-				if (MHI_TRE_DATA_GET_IEOB(el)) {
-					ret = mhi_ep_send_completion_event(mhi_cntrl, ring, el,
-								     MHI_TRE_DATA_GET_LEN(el),
-								     MHI_EV_CC_EOB);
-					if (ret < 0) {
-						dev_err(&mhi_chan->mhi_dev->dev,
-							"Error sending transfer compl. event\n");
-						return ret;
-					}
-				}
-			} else {
-				/*
-				 * IEOT (Interrupt on End of Transfer) flag will be set by the host
-				 * for the last TRE of the TD and expects the completion event for
-				 * the same.
-				 */
-				if (MHI_TRE_DATA_GET_IEOT(el)) {
-					ret = mhi_ep_send_completion_event(mhi_cntrl, ring, el,
-								     MHI_TRE_DATA_GET_LEN(el),
-								     MHI_EV_CC_EOT);
-					if (ret < 0) {
-						dev_err(&mhi_chan->mhi_dev->dev,
-							"Error sending transfer compl. event\n");
-						return ret;
-					}
-				}
-
+			if (MHI_TRE_DATA_GET_IEOT(el))
 				tr_done = true;
-			}
 
-			mhi_ep_ring_inc_index(ring);
+			mhi_chan->rd_offset = (mhi_chan->rd_offset + 1) % ring->ring_size;
 		}
-
-		result->bytes_xferd += tr_len;
 	} while (buf_left && !tr_done);
 
 	return 0;
+
+err_free_buf_addr:
+	kmem_cache_free(mhi_cntrl->tre_buf_cache, buf_addr);
+
+	return ret;
 }
 
-static int mhi_ep_process_ch_ring(struct mhi_ep_ring *ring, struct mhi_ring_element *el)
+static int mhi_ep_process_ch_ring(struct mhi_ep_ring *ring)
 {
 	struct mhi_ep_cntrl *mhi_cntrl = ring->mhi_cntrl;
 	struct mhi_result result = {};
-	u32 len = MHI_EP_DEFAULT_MTU;
 	struct mhi_ep_chan *mhi_chan;
 	int ret;
 
@@ -452,32 +502,49 @@ static int mhi_ep_process_ch_ring(struct mhi_ep_ring *ring, struct mhi_ring_elem
 		mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result);
 	} else {
 		/* UL channel */
-		result.buf_addr = kmem_cache_zalloc(mhi_cntrl->tre_buf_cache, GFP_KERNEL | GFP_DMA);
-		if (!result.buf_addr)
-			return -ENOMEM;
-
 		do {
-			ret = mhi_ep_read_channel(mhi_cntrl, ring, &result, len);
+			ret = mhi_ep_read_channel(mhi_cntrl, ring);
 			if (ret < 0) {
 				dev_err(&mhi_chan->mhi_dev->dev, "Failed to read channel\n");
-				kmem_cache_free(mhi_cntrl->tre_buf_cache, result.buf_addr);
 				return ret;
 			}
 
-			result.dir = mhi_chan->dir;
-			mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result);
-			result.bytes_xferd = 0;
-			memset(result.buf_addr, 0, len);
-
 			/* Read until the ring becomes empty */
 		} while (!mhi_ep_queue_is_empty(mhi_chan->mhi_dev, DMA_TO_DEVICE));
-
-		kmem_cache_free(mhi_cntrl->tre_buf_cache, result.buf_addr);
 	}
 
 	return 0;
 }
 
+static void mhi_ep_skb_completion(struct mhi_ep_buf_info *buf_info)
+{
+	struct mhi_ep_device *mhi_dev = buf_info->mhi_dev;
+	struct mhi_ep_cntrl *mhi_cntrl = mhi_dev->mhi_cntrl;
+	struct mhi_ep_chan *mhi_chan = mhi_dev->dl_chan;
+	struct mhi_ep_ring *ring = &mhi_cntrl->mhi_chan[mhi_chan->chan].ring;
+	struct mhi_ring_element *el = &ring->ring_cache[ring->rd_offset];
+	struct device *dev = &mhi_dev->dev;
+	struct mhi_result result = {};
+	int ret;
+
+	if (mhi_chan->xfer_cb) {
+		result.buf_addr = buf_info->cb_buf;
+		result.dir = mhi_chan->dir;
+		result.bytes_xferd = buf_info->size;
+
+		mhi_chan->xfer_cb(mhi_dev, &result);
+	}
+
+	ret = mhi_ep_send_completion_event(mhi_cntrl, ring, el, buf_info->size,
+					   buf_info->code);
+	if (ret) {
+		dev_err(dev, "Error sending transfer completion event\n");
+		return;
+	}
+
+	mhi_ep_ring_inc_index(ring);
+}
+
 /* TODO: Handle partially formed TDs */
 int mhi_ep_queue_skb(struct mhi_ep_device *mhi_dev, struct sk_buff *skb)
 {
@@ -488,7 +555,6 @@ int mhi_ep_queue_skb(struct mhi_ep_device *mhi_dev, struct sk_buff *skb)
 	struct mhi_ring_element *el;
 	u32 buf_left, read_offset;
 	struct mhi_ep_ring *ring;
-	enum mhi_ev_ccs code;
 	size_t tr_len;
 	u32 tre_len;
 	int ret;
@@ -512,7 +578,7 @@ int mhi_ep_queue_skb(struct mhi_ep_device *mhi_dev, struct sk_buff *skb)
 			goto err_exit;
 		}
 
-		el = &ring->ring_cache[ring->rd_offset];
+		el = &ring->ring_cache[mhi_chan->rd_offset];
 		tre_len = MHI_TRE_DATA_GET_LEN(el);
 
 		tr_len = min(buf_left, tre_len);
@@ -521,33 +587,35 @@ int mhi_ep_queue_skb(struct mhi_ep_device *mhi_dev, struct sk_buff *skb)
 		buf_info.dev_addr = skb->data + read_offset;
 		buf_info.host_addr = MHI_TRE_DATA_GET_PTR(el);
 		buf_info.size = tr_len;
+		buf_info.cb = mhi_ep_skb_completion;
+		buf_info.cb_buf = skb;
+		buf_info.mhi_dev = mhi_dev;
 
-		dev_dbg(dev, "Writing %zd bytes to channel (%u)\n", tr_len, ring->ch_id);
-		ret = mhi_cntrl->write_to_host(mhi_cntrl, &buf_info);
-		if (ret < 0) {
-			dev_err(dev, "Error writing to the channel\n");
-			goto err_exit;
-		}
-
-		buf_left -= tr_len;
 		/*
 		 * For all TREs queued by the host for DL channel, only the EOT flag will be set.
 		 * If the packet doesn't fit into a single TRE, send the OVERFLOW event to
 		 * the host so that the host can adjust the packet boundary to next TREs. Else send
 		 * the EOT event to the host indicating the packet boundary.
 		 */
-		if (buf_left)
-			code = MHI_EV_CC_OVERFLOW;
+		if (buf_left - tr_len)
+			buf_info.code = MHI_EV_CC_OVERFLOW;
 		else
-			code = MHI_EV_CC_EOT;
+			buf_info.code = MHI_EV_CC_EOT;
 
-		ret = mhi_ep_send_completion_event(mhi_cntrl, ring, el, tr_len, code);
-		if (ret) {
-			dev_err(dev, "Error sending transfer completion event\n");
+		dev_dbg(dev, "Writing %zd bytes to channel (%u)\n", tr_len, ring->ch_id);
+		ret = mhi_cntrl->write_async(mhi_cntrl, &buf_info);
+		if (ret < 0) {
+			dev_err(dev, "Error writing to the channel\n");
 			goto err_exit;
 		}
 
-		mhi_ep_ring_inc_index(ring);
+		buf_left -= tr_len;
+
+		/*
+		 * Update the read offset cached in mhi_chan. Actual read offset
+		 * will be updated by the completion handler.
+		 */
+		mhi_chan->rd_offset = (mhi_chan->rd_offset + 1) % ring->ring_size;
 	} while (buf_left);
 
 	mutex_unlock(&mhi_chan->lock);
@@ -748,7 +816,6 @@ static void mhi_ep_ch_ring_worker(struct work_struct *work)
 	struct mhi_ep_cntrl *mhi_cntrl = container_of(work, struct mhi_ep_cntrl, ch_ring_work);
 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
 	struct mhi_ep_ring_item *itr, *tmp;
-	struct mhi_ring_element *el;
 	struct mhi_ep_ring *ring;
 	struct mhi_ep_chan *chan;
 	unsigned long flags;
@@ -787,16 +854,14 @@ static void mhi_ep_ch_ring_worker(struct work_struct *work)
 		}
 
 		/* Sanity check to make sure there are elements in the ring */
-		if (ring->rd_offset == ring->wr_offset) {
+		if (chan->rd_offset == ring->wr_offset) {
 			mutex_unlock(&chan->lock);
 			kmem_cache_free(mhi_cntrl->ring_item_cache, itr);
 			continue;
 		}
 
-		el = &ring->ring_cache[ring->rd_offset];
-
 		dev_dbg(dev, "Processing the ring for channel (%u)\n", ring->ch_id);
-		ret = mhi_ep_process_ch_ring(ring, el);
+		ret = mhi_ep_process_ch_ring(ring);
 		if (ret) {
 			dev_err(dev, "Error processing ring for channel (%u): %d\n",
 				ring->ch_id, ret);
@@ -1399,6 +1464,10 @@ int mhi_ep_register_controller(struct mhi_ep_cntrl *mhi_cntrl,
 	if (!mhi_cntrl || !mhi_cntrl->cntrl_dev || !mhi_cntrl->mmio || !mhi_cntrl->irq)
 		return -EINVAL;
 
+	if (!mhi_cntrl->read_sync || !mhi_cntrl->write_sync ||
+	    !mhi_cntrl->read_async || !mhi_cntrl->write_async)
+		return -EINVAL;
+
 	ret = mhi_ep_chan_init(mhi_cntrl, config);
 	if (ret)
 		return ret;
@@ -1431,6 +1500,7 @@ int mhi_ep_register_controller(struct mhi_ep_cntrl *mhi_cntrl,
 		ret = -ENOMEM;
 		goto err_destroy_tre_buf_cache;
 	}
+
 	INIT_WORK(&mhi_cntrl->state_work, mhi_ep_state_worker);
 	INIT_WORK(&mhi_cntrl->reset_work, mhi_ep_reset_worker);
 	INIT_WORK(&mhi_cntrl->cmd_ring_work, mhi_ep_cmd_ring_worker);