drivers/tty: make pty.c slightly more explicitly non-modular
[firefly-linux-kernel-4.4.55.git] / drivers / ntb / ntb_transport.c
index 1c6386d5f79c742737e4ee1a8a2b99df686ffaa0..6e3ee907d18613be26c2f23d759637de60282a17 100644 (file)
@@ -119,7 +119,8 @@ struct ntb_transport_qp {
        struct ntb_transport_ctx *transport;
        struct ntb_dev *ndev;
        void *cb_data;
-       struct dma_chan *dma_chan;
+       struct dma_chan *tx_dma_chan;
+       struct dma_chan *rx_dma_chan;
 
        bool client_ready;
        bool link_is_up;
@@ -297,7 +298,7 @@ static LIST_HEAD(ntb_transport_list);
 
 static int ntb_bus_init(struct ntb_transport_ctx *nt)
 {
-       list_add(&nt->entry, &ntb_transport_list);
+       list_add_tail(&nt->entry, &ntb_transport_list);
        return 0;
 }
 
@@ -452,7 +453,7 @@ static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count,
 
        out_offset = 0;
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "NTB QP stats\n");
+                              "\nNTB QP stats:\n\n");
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
                               "rx_bytes - \t%llu\n", qp->rx_bytes);
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
@@ -470,11 +471,11 @@ static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count,
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
                               "rx_err_ver - \t%llu\n", qp->rx_err_ver);
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "rx_buff - \t%p\n", qp->rx_buff);
+                              "rx_buff - \t0x%p\n", qp->rx_buff);
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
                               "rx_index - \t%u\n", qp->rx_index);
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "rx_max_entry - \t%u\n", qp->rx_max_entry);
+                              "rx_max_entry - \t%u\n\n", qp->rx_max_entry);
 
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
                               "tx_bytes - \t%llu\n", qp->tx_bytes);
@@ -489,15 +490,32 @@ static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count,
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
                               "tx_err_no_buf - %llu\n", qp->tx_err_no_buf);
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "tx_mw - \t%p\n", qp->tx_mw);
+                              "tx_mw - \t0x%p\n", qp->tx_mw);
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "tx_index - \t%u\n", qp->tx_index);
+                              "tx_index (H) - \t%u\n", qp->tx_index);
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "RRI (T) - \t%u\n",
+                              qp->remote_rx_info->entry);
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
                               "tx_max_entry - \t%u\n", qp->tx_max_entry);
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "free tx - \t%u\n",
+                              ntb_transport_tx_free_entry(qp));
 
        out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "\nQP Link %s\n",
+                              "\n");
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "Using TX DMA - \t%s\n",
+                              qp->tx_dma_chan ? "Yes" : "No");
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "Using RX DMA - \t%s\n",
+                              qp->rx_dma_chan ? "Yes" : "No");
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "QP Link - \t%s\n",
                               qp->link_is_up ? "Up" : "Down");
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "\n");
+
        if (out_offset > out_count)
                out_offset = out_count;
 
@@ -535,6 +553,7 @@ static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock,
        }
        entry = list_first_entry(list, struct ntb_queue_entry, entry);
        list_del(&entry->entry);
+
 out:
        spin_unlock_irqrestore(lock, flags);
 
@@ -1206,7 +1225,7 @@ static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset)
 {
        struct dma_async_tx_descriptor *txd;
        struct ntb_transport_qp *qp = entry->qp;
-       struct dma_chan *chan = qp->dma_chan;
+       struct dma_chan *chan = qp->rx_dma_chan;
        struct dma_device *device;
        size_t pay_off, buff_off, len;
        struct dmaengine_unmap_data *unmap;
@@ -1219,18 +1238,18 @@ static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset)
                goto err;
 
        if (len < copy_bytes)
-               goto err_wait;
+               goto err;
 
        device = chan->device;
        pay_off = (size_t)offset & ~PAGE_MASK;
        buff_off = (size_t)buf & ~PAGE_MASK;
 
        if (!is_dma_copy_aligned(device, pay_off, buff_off, len))
-               goto err_wait;
+               goto err;
 
        unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT);
        if (!unmap)
-               goto err_wait;
+               goto err;
 
        unmap->len = len;
        unmap->addr[0] = dma_map_page(device->dev, virt_to_page(offset),
@@ -1273,12 +1292,6 @@ err_set_unmap:
        dmaengine_unmap_put(unmap);
 err_get_unmap:
        dmaengine_unmap_put(unmap);
-err_wait:
-       /* If the callbacks come out of order, the writing of the index to the
-        * last completed will be out of order.  This may result in the
-        * receive stalling forever.
-        */
-       dma_sync_wait(chan, qp->last_cookie);
 err:
        ntb_memcpy_rx(entry, offset);
        qp->rx_memcpy++;
@@ -1373,8 +1386,8 @@ static void ntb_transport_rxc_db(unsigned long data)
                        break;
        }
 
-       if (i && qp->dma_chan)
-               dma_async_issue_pending(qp->dma_chan);
+       if (i && qp->rx_dma_chan)
+               dma_async_issue_pending(qp->rx_dma_chan);
 
        if (i == qp->rx_max_entry) {
                /* there is more work to do */
@@ -1441,7 +1454,7 @@ static void ntb_async_tx(struct ntb_transport_qp *qp,
 {
        struct ntb_payload_header __iomem *hdr;
        struct dma_async_tx_descriptor *txd;
-       struct dma_chan *chan = qp->dma_chan;
+       struct dma_chan *chan = qp->tx_dma_chan;
        struct dma_device *device;
        size_t dest_off, buff_off;
        struct dmaengine_unmap_data *unmap;
@@ -1634,14 +1647,27 @@ ntb_transport_create_queue(void *data, struct device *client_dev,
        dma_cap_set(DMA_MEMCPY, dma_mask);
 
        if (use_dma) {
-               qp->dma_chan = dma_request_channel(dma_mask, ntb_dma_filter_fn,
-                                                  (void *)(unsigned long)node);
-               if (!qp->dma_chan)
-                       dev_info(&pdev->dev, "Unable to allocate DMA channel\n");
+               qp->tx_dma_chan =
+                       dma_request_channel(dma_mask, ntb_dma_filter_fn,
+                                           (void *)(unsigned long)node);
+               if (!qp->tx_dma_chan)
+                       dev_info(&pdev->dev, "Unable to allocate TX DMA channel\n");
+
+               qp->rx_dma_chan =
+                       dma_request_channel(dma_mask, ntb_dma_filter_fn,
+                                           (void *)(unsigned long)node);
+               if (!qp->rx_dma_chan)
+                       dev_info(&pdev->dev, "Unable to allocate RX DMA channel\n");
        } else {
-               qp->dma_chan = NULL;
+               qp->tx_dma_chan = NULL;
+               qp->rx_dma_chan = NULL;
        }
-       dev_dbg(&pdev->dev, "Using %s memcpy\n", qp->dma_chan ? "DMA" : "CPU");
+
+       dev_dbg(&pdev->dev, "Using %s memcpy for TX\n",
+               qp->tx_dma_chan ? "DMA" : "CPU");
+
+       dev_dbg(&pdev->dev, "Using %s memcpy for RX\n",
+               qp->rx_dma_chan ? "DMA" : "CPU");
 
        for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
                entry = kzalloc_node(sizeof(*entry), GFP_ATOMIC, node);
@@ -1676,8 +1702,10 @@ err2:
 err1:
        while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q)))
                kfree(entry);
-       if (qp->dma_chan)
-               dma_release_channel(qp->dma_chan);
+       if (qp->tx_dma_chan)
+               dma_release_channel(qp->tx_dma_chan);
+       if (qp->rx_dma_chan)
+               dma_release_channel(qp->rx_dma_chan);
        nt->qp_bitmap_free |= qp_bit;
 err:
        return NULL;
@@ -1701,12 +1729,27 @@ void ntb_transport_free_queue(struct ntb_transport_qp *qp)
 
        pdev = qp->ndev->pdev;
 
-       if (qp->dma_chan) {
-               struct dma_chan *chan = qp->dma_chan;
+       if (qp->tx_dma_chan) {
+               struct dma_chan *chan = qp->tx_dma_chan;
+               /* Putting the dma_chan to NULL will force any new traffic to be
+                * processed by the CPU instead of the DAM engine
+                */
+               qp->tx_dma_chan = NULL;
+
+               /* Try to be nice and wait for any queued DMA engine
+                * transactions to process before smashing it with a rock
+                */
+               dma_sync_wait(chan, qp->last_cookie);
+               dmaengine_terminate_all(chan);
+               dma_release_channel(chan);
+       }
+
+       if (qp->rx_dma_chan) {
+               struct dma_chan *chan = qp->rx_dma_chan;
                /* Putting the dma_chan to NULL will force any new traffic to be
                 * processed by the CPU instead of the DAM engine
                 */
-               qp->dma_chan = NULL;
+               qp->rx_dma_chan = NULL;
 
                /* Try to be nice and wait for any queued DMA engine
                 * transactions to process before smashing it with a rock
@@ -1843,7 +1886,7 @@ int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data,
        entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q);
        if (!entry) {
                qp->tx_err_no_buf++;
-               return -ENOMEM;
+               return -EBUSY;
        }
 
        entry->cb_data = cb;
@@ -1954,21 +1997,34 @@ EXPORT_SYMBOL_GPL(ntb_transport_qp_num);
 unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp)
 {
        unsigned int max;
+       unsigned int copy_align;
 
        if (!qp)
                return 0;
 
-       if (!qp->dma_chan)
+       if (!qp->tx_dma_chan && !qp->rx_dma_chan)
                return qp->tx_max_frame - sizeof(struct ntb_payload_header);
 
+       copy_align = max(qp->tx_dma_chan->device->copy_align,
+                        qp->rx_dma_chan->device->copy_align);
+
        /* If DMA engine usage is possible, try to find the max size for that */
        max = qp->tx_max_frame - sizeof(struct ntb_payload_header);
-       max -= max % (1 << qp->dma_chan->device->copy_align);
+       max -= max % (1 << copy_align);
 
        return max;
 }
 EXPORT_SYMBOL_GPL(ntb_transport_max_size);
 
+unsigned int ntb_transport_tx_free_entry(struct ntb_transport_qp *qp)
+{
+       unsigned int head = qp->tx_index;
+       unsigned int tail = qp->remote_rx_info->entry;
+
+       return tail > head ? tail - head : qp->tx_max_entry + tail - head;
+}
+EXPORT_SYMBOL_GPL(ntb_transport_tx_free_entry);
+
 static void ntb_transport_doorbell_callback(void *data, int vector)
 {
        struct ntb_transport_ctx *nt = data;