*/
#include <linux/debugfs.h>
#include <linux/delay.h>
+#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/export.h>
module_param(max_num_clients, byte, 0644);
MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients");
+static unsigned int copy_bytes = 1024;
+module_param(copy_bytes, uint, 0644);
+MODULE_PARM_DESC(copy_bytes, "Threshold under which NTB will use the CPU to copy instead of DMA");
+
struct ntb_queue_entry {
/* ntb_queue list reference */
struct list_head entry;
void *buf;
unsigned int len;
unsigned int flags;
+
+ struct ntb_transport_qp *qp;
+ union {
+ struct ntb_payload_header __iomem *tx_hdr;
+ struct ntb_payload_header *rx_hdr;
+ };
+ unsigned int index;
};
struct ntb_rx_info {
struct ntb_transport *transport;
struct ntb_device *ndev;
void *cb_data;
+ struct dma_chan *dma_chan;
bool client_ready;
bool qp_link;
struct list_head tx_free_q;
spinlock_t ntb_tx_free_q_lock;
void __iomem *tx_mw;
+ dma_addr_t tx_mw_phys;
unsigned int tx_index;
unsigned int tx_max_entry;
unsigned int tx_max_frame;
unsigned int rx_index;
unsigned int rx_max_entry;
unsigned int rx_max_frame;
+ dma_cookie_t last_cookie;
void (*event_handler) (void *data, int status);
struct delayed_work link_work;
u64 rx_err_no_buf;
u64 rx_err_oflow;
u64 rx_err_ver;
+ u64 rx_memcpy;
+ u64 rx_async;
u64 tx_bytes;
u64 tx_pkts;
u64 tx_ring_full;
+ u64 tx_err_no_buf;
+ u64 tx_memcpy;
+ u64 tx_async;
};
struct ntb_transport_mw {
char *buf;
ssize_t ret, out_offset, out_count;
- out_count = 600;
+ out_count = 1000;
buf = kmalloc(out_count, GFP_KERNEL);
if (!buf)
"rx_bytes - \t%llu\n", qp->rx_bytes);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
"rx_pkts - \t%llu\n", qp->rx_pkts);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_memcpy - \t%llu\n", qp->rx_memcpy);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_async - \t%llu\n", qp->rx_async);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
"rx_ring_empty - %llu\n", qp->rx_ring_empty);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
"tx_bytes - \t%llu\n", qp->tx_bytes);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
"tx_pkts - \t%llu\n", qp->tx_pkts);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_memcpy - \t%llu\n", qp->tx_memcpy);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_async - \t%llu\n", qp->tx_async);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
"tx_ring_full - \t%llu\n", qp->tx_ring_full);
+ 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);
out_offset += snprintf(buf + out_offset, out_count - out_offset,
num_qps_mw = nt->max_qps / mw_max;
rx_size = (unsigned int) nt->mw[mw_num].size / num_qps_mw;
- qp->remote_rx_info = nt->mw[mw_num].virt_addr +
- (qp_num / mw_max * rx_size);
+ qp->rx_buff = nt->mw[mw_num].virt_addr + qp_num / mw_max * rx_size;
rx_size -= sizeof(struct ntb_rx_info);
- qp->rx_buff = qp->remote_rx_info + 1;
+ qp->remote_rx_info = qp->rx_buff + rx_size;
+
/* Due to housekeeping, there must be atleast 2 buffs */
qp->rx_max_frame = min(transport_mtu, rx_size / 2);
qp->rx_max_entry = rx_size / qp->rx_max_frame;
msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
}
-static void ntb_transport_init_queue(struct ntb_transport *nt,
+static int ntb_transport_init_queue(struct ntb_transport *nt,
unsigned int qp_num)
{
struct ntb_transport_qp *qp;
unsigned int num_qps_mw, tx_size;
u8 mw_num, mw_max;
+ u64 qp_offset;
mw_max = ntb_max_mw(nt->ndev);
mw_num = QP_TO_MW(nt->ndev, qp_num);
num_qps_mw = nt->max_qps / mw_max;
tx_size = (unsigned int) ntb_get_mw_size(qp->ndev, mw_num) / num_qps_mw;
- qp->rx_info = ntb_get_mw_vbase(nt->ndev, mw_num) +
- (qp_num / mw_max * tx_size);
+ qp_offset = qp_num / mw_max * tx_size;
+ qp->tx_mw = ntb_get_mw_vbase(nt->ndev, mw_num) + qp_offset;
+ if (!qp->tx_mw)
+ return -EINVAL;
+
+ qp->tx_mw_phys = ntb_get_mw_base(qp->ndev, mw_num) + qp_offset;
+ if (!qp->tx_mw_phys)
+ return -EINVAL;
+
tx_size -= sizeof(struct ntb_rx_info);
+ qp->rx_info = qp->tx_mw + tx_size;
- qp->tx_mw = qp->rx_info + 1;
/* Due to housekeeping, there must be atleast 2 buffs */
qp->tx_max_frame = min(transport_mtu, tx_size / 2);
qp->tx_max_entry = tx_size / qp->tx_max_frame;
INIT_LIST_HEAD(&qp->rx_pend_q);
INIT_LIST_HEAD(&qp->rx_free_q);
INIT_LIST_HEAD(&qp->tx_free_q);
+
+ return 0;
}
int ntb_transport_init(struct pci_dev *pdev)
nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1;
- for (i = 0; i < nt->max_qps; i++)
- ntb_transport_init_queue(nt, i);
+ for (i = 0; i < nt->max_qps; i++) {
+ rc = ntb_transport_init_queue(nt, i);
+ if (rc)
+ goto err3;
+ }
INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work);
INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup);
kfree(nt);
}
-static void ntb_rx_copy_task(struct ntb_transport_qp *qp,
- struct ntb_queue_entry *entry, void *offset)
+static void ntb_rx_copy_callback(void *data)
{
+ struct ntb_queue_entry *entry = data;
+ struct ntb_transport_qp *qp = entry->qp;
void *cb_data = entry->cb_data;
unsigned int len = entry->len;
+ struct ntb_payload_header *hdr = entry->rx_hdr;
+
+ /* Ensure that the data is fully copied out before clearing the flag */
+ wmb();
+ hdr->flags = 0;
- memcpy(entry->buf, offset, entry->len);
+ iowrite32(entry->index, &qp->rx_info->entry);
ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q);
qp->rx_handler(qp, qp->cb_data, cb_data, len);
}
+static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset)
+{
+ void *buf = entry->buf;
+ size_t len = entry->len;
+
+ memcpy(buf, offset, len);
+
+ ntb_rx_copy_callback(entry);
+}
+
+static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset,
+ size_t len)
+{
+ struct dma_async_tx_descriptor *txd;
+ struct ntb_transport_qp *qp = entry->qp;
+ struct dma_chan *chan = qp->dma_chan;
+ struct dma_device *device;
+ size_t pay_off, buff_off;
+ dma_addr_t src, dest;
+ dma_cookie_t cookie;
+ void *buf = entry->buf;
+ unsigned long flags;
+
+ entry->len = len;
+
+ if (!chan)
+ goto err;
+
+ if (len < copy_bytes)
+ goto err1;
+
+ 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 err1;
+
+ dest = dma_map_single(device->dev, buf, len, DMA_FROM_DEVICE);
+ if (dma_mapping_error(device->dev, dest))
+ goto err1;
+
+ src = dma_map_single(device->dev, offset, len, DMA_TO_DEVICE);
+ if (dma_mapping_error(device->dev, src))
+ goto err2;
+
+ flags = DMA_COMPL_DEST_UNMAP_SINGLE | DMA_COMPL_SRC_UNMAP_SINGLE |
+ DMA_PREP_INTERRUPT;
+ txd = device->device_prep_dma_memcpy(chan, dest, src, len, flags);
+ if (!txd)
+ goto err3;
+
+ txd->callback = ntb_rx_copy_callback;
+ txd->callback_param = entry;
+
+ cookie = dmaengine_submit(txd);
+ if (dma_submit_error(cookie))
+ goto err3;
+
+ qp->last_cookie = cookie;
+
+ qp->rx_async++;
+
+ return;
+
+err3:
+ dma_unmap_single(device->dev, src, len, DMA_TO_DEVICE);
+err2:
+ dma_unmap_single(device->dev, dest, len, DMA_FROM_DEVICE);
+err1:
+ /* 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++;
+}
+
static int ntb_process_rxc(struct ntb_transport_qp *qp)
{
struct ntb_payload_header *hdr;
if (hdr->flags & LINK_DOWN_FLAG) {
ntb_qp_link_down(qp);
- ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry,
- &qp->rx_pend_q);
- goto out;
+ goto err;
}
dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
"rx offset %u, ver %u - %d payload received, buf size %d\n",
qp->rx_index, hdr->ver, hdr->len, entry->len);
- if (hdr->len <= entry->len) {
- entry->len = hdr->len;
- ntb_rx_copy_task(qp, entry, offset);
- } else {
- ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry,
- &qp->rx_pend_q);
+ qp->rx_bytes += hdr->len;
+ qp->rx_pkts++;
+ if (hdr->len > entry->len) {
qp->rx_err_oflow++;
dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
"RX overflow! Wanted %d got %d\n",
hdr->len, entry->len);
+
+ goto err;
}
- qp->rx_bytes += hdr->len;
- qp->rx_pkts++;
+ entry->index = qp->rx_index;
+ entry->rx_hdr = hdr;
+
+ ntb_async_rx(entry, offset, hdr->len);
out:
+ qp->rx_index++;
+ qp->rx_index %= qp->rx_max_entry;
+
+ return 0;
+
+err:
+ ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry,
+ &qp->rx_pend_q);
/* Ensure that the data is fully copied out before clearing the flag */
wmb();
hdr->flags = 0;
iowrite32(qp->rx_index, &qp->rx_info->entry);
- qp->rx_index++;
- qp->rx_index %= qp->rx_max_entry;
-
- return 0;
+ goto out;
}
static void ntb_transport_rx(unsigned long data)
if (rc)
break;
}
+
+ if (qp->dma_chan)
+ dma_async_issue_pending(qp->dma_chan);
}
static void ntb_transport_rxc_db(void *data, int db_num)
tasklet_schedule(&qp->rx_work);
}
-static void ntb_tx_copy_task(struct ntb_transport_qp *qp,
- struct ntb_queue_entry *entry,
- void __iomem *offset)
+static void ntb_tx_copy_callback(void *data)
{
- struct ntb_payload_header __iomem *hdr;
-
- memcpy_toio(offset, entry->buf, entry->len);
+ struct ntb_queue_entry *entry = data;
+ struct ntb_transport_qp *qp = entry->qp;
+ struct ntb_payload_header __iomem *hdr = entry->tx_hdr;
- hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header);
- iowrite32(entry->len, &hdr->len);
- iowrite32((u32) qp->tx_pkts, &hdr->ver);
-
- /* Ensure that the data is fully copied out before setting the flag */
+ /* Ensure that the data is fully copied out before setting the flags */
wmb();
iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags);
ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q);
}
-static int ntb_process_tx(struct ntb_transport_qp *qp,
- struct ntb_queue_entry *entry)
+static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset)
{
+ memcpy_toio(offset, entry->buf, entry->len);
+
+ ntb_tx_copy_callback(entry);
+}
+
+static void ntb_async_tx(struct ntb_transport_qp *qp,
+ struct ntb_queue_entry *entry)
+{
+ struct ntb_payload_header __iomem *hdr;
+ struct dma_async_tx_descriptor *txd;
+ struct dma_chan *chan = qp->dma_chan;
+ struct dma_device *device;
+ size_t dest_off, buff_off;
+ dma_addr_t src, dest;
+ dma_cookie_t cookie;
void __iomem *offset;
+ size_t len = entry->len;
+ void *buf = entry->buf;
+ unsigned long flags;
offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index;
+ hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header);
+ entry->tx_hdr = hdr;
- dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - offset %p, tx %u, entry len %d flags %x buff %p\n",
- qp->tx_pkts, offset, qp->tx_index, entry->len, entry->flags,
+ iowrite32(entry->len, &hdr->len);
+ iowrite32((u32) qp->tx_pkts, &hdr->ver);
+
+ if (!chan)
+ goto err;
+
+ if (len < copy_bytes)
+ goto err;
+
+ device = chan->device;
+ dest = qp->tx_mw_phys + qp->tx_max_frame * qp->tx_index;
+ buff_off = (size_t) buf & ~PAGE_MASK;
+ dest_off = (size_t) dest & ~PAGE_MASK;
+
+ if (!is_dma_copy_aligned(device, buff_off, dest_off, len))
+ goto err;
+
+ src = dma_map_single(device->dev, buf, len, DMA_TO_DEVICE);
+ if (dma_mapping_error(device->dev, src))
+ goto err;
+
+ flags = DMA_COMPL_SRC_UNMAP_SINGLE | DMA_PREP_INTERRUPT;
+ txd = device->device_prep_dma_memcpy(chan, dest, src, len, flags);
+ if (!txd)
+ goto err1;
+
+ txd->callback = ntb_tx_copy_callback;
+ txd->callback_param = entry;
+
+ cookie = dmaengine_submit(txd);
+ if (dma_submit_error(cookie))
+ goto err1;
+
+ dma_async_issue_pending(chan);
+ qp->tx_async++;
+
+ return;
+err1:
+ dma_unmap_single(device->dev, src, len, DMA_TO_DEVICE);
+err:
+ ntb_memcpy_tx(entry, offset);
+ qp->tx_memcpy++;
+}
+
+static int ntb_process_tx(struct ntb_transport_qp *qp,
+ struct ntb_queue_entry *entry)
+{
+ dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - tx %u, entry len %d flags %x buff %p\n",
+ qp->tx_pkts, qp->tx_index, entry->len, entry->flags,
entry->buf);
if (qp->tx_index == qp->remote_rx_info->entry) {
qp->tx_ring_full++;
return 0;
}
- ntb_tx_copy_task(qp, entry, offset);
+ ntb_async_tx(qp, entry);
qp->tx_index++;
qp->tx_index %= qp->tx_max_entry;
qp->tx_handler = handlers->tx_handler;
qp->event_handler = handlers->event_handler;
+ qp->dma_chan = dma_find_channel(DMA_MEMCPY);
+ if (!qp->dma_chan)
+ dev_info(&pdev->dev, "Unable to allocate DMA channel, using CPU instead\n");
+ else
+ dmaengine_get();
+
for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC);
if (!entry)
goto err1;
+ entry->qp = qp;
ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry,
&qp->rx_free_q);
}
if (!entry)
goto err2;
+ entry->qp = qp;
ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
&qp->tx_free_q);
}
pdev = ntb_query_pdev(qp->ndev);
- cancel_delayed_work_sync(&qp->link_work);
+ if (qp->dma_chan) {
+ struct dma_chan *chan = qp->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;
+
+ /* 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);
+ dmaengine_put();
+ }
ntb_unregister_db_callback(qp->ndev, qp->qp_num);
tasklet_disable(&qp->rx_work);
+ cancel_delayed_work_sync(&qp->link_work);
+
while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q)))
kfree(entry);
return -EINVAL;
entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q);
- if (!entry)
+ if (!entry) {
+ qp->tx_err_no_buf++;
return -ENOMEM;
+ }
entry->cb_data = cb;
entry->buf = data;
*/
unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp)
{
+ unsigned int max;
+
if (!qp)
return 0;
- return qp->tx_max_frame - sizeof(struct ntb_payload_header);
+ if (!qp->dma_chan)
+ return qp->tx_max_frame - sizeof(struct ntb_payload_header);
+
+ /* 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);
+
+ return max;
}
EXPORT_SYMBOL_GPL(ntb_transport_max_size);
projects / linux-drm-fsl-dcu.git / commitdiff