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path: root/drivers/net/wireless/mediatek/mt76/mt76x0/dma.c
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Diffstat (limited to 'drivers/net/wireless/mediatek/mt76/mt76x0/dma.c')
-rw-r--r--drivers/net/wireless/mediatek/mt76/mt76x0/dma.c528
1 files changed, 528 insertions, 0 deletions
diff --git a/drivers/net/wireless/mediatek/mt76/mt76x0/dma.c b/drivers/net/wireless/mediatek/mt76/mt76x0/dma.c
new file mode 100644
index 0000000..4877f4d
--- /dev/null
+++ b/drivers/net/wireless/mediatek/mt76/mt76x0/dma.c
@@ -0,0 +1,528 @@
+/*
+ * Copyright (C) 2015 Jakub Kicinski <kubakici@wp.pl>
+ * Copyright (C) 2018 Stanislaw Gruszka <stf_xl@wp.pl>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include "mt76x0.h"
+#include "dma.h"
+#include "usb.h"
+#include "trace.h"
+
+static int mt76x0_submit_rx_buf(struct mt76x0_dev *dev,
+ struct mt76x0_dma_buf_rx *e, gfp_t gfp);
+
+static unsigned int ieee80211_get_hdrlen_from_buf(const u8 *data, unsigned len)
+{
+ const struct ieee80211_hdr *hdr = (const struct ieee80211_hdr *)data;
+ unsigned int hdrlen;
+
+ if (unlikely(len < 10))
+ return 0;
+ hdrlen = ieee80211_hdrlen(hdr->frame_control);
+ if (unlikely(hdrlen > len))
+ return 0;
+ return hdrlen;
+}
+
+static struct sk_buff *
+mt76x0_rx_skb_from_seg(struct mt76x0_dev *dev, struct mt76x0_rxwi *rxwi,
+ void *data, u32 seg_len, u32 truesize, struct page *p)
+{
+ struct sk_buff *skb;
+ u32 true_len, hdr_len = 0, copy, frag;
+
+ skb = alloc_skb(p ? 128 : seg_len, GFP_ATOMIC);
+ if (!skb)
+ return NULL;
+
+ true_len = mt76x0_mac_process_rx(dev, skb, data, rxwi);
+ if (!true_len || true_len > seg_len)
+ goto bad_frame;
+
+ hdr_len = ieee80211_get_hdrlen_from_buf(data, true_len);
+ if (!hdr_len)
+ goto bad_frame;
+
+ if (rxwi->rxinfo & cpu_to_le32(MT_RXINFO_L2PAD)) {
+ memcpy(skb_put(skb, hdr_len), data, hdr_len);
+
+ data += hdr_len + 2;
+ true_len -= hdr_len;
+ hdr_len = 0;
+ }
+
+ /* If not doing paged RX allocated skb will always have enough space */
+ copy = (true_len <= skb_tailroom(skb)) ? true_len : hdr_len + 8;
+ frag = true_len - copy;
+
+ memcpy(skb_put(skb, copy), data, copy);
+ data += copy;
+
+ if (frag) {
+ skb_add_rx_frag(skb, 0, p, data - page_address(p),
+ frag, truesize);
+ get_page(p);
+ }
+
+ return skb;
+
+bad_frame:
+ dev_err_ratelimited(dev->mt76.dev, "Error: incorrect frame len:%u hdr:%u\n",
+ true_len, hdr_len);
+ dev_kfree_skb(skb);
+ return NULL;
+}
+
+static void mt76x0_rx_process_seg(struct mt76x0_dev *dev, u8 *data,
+ u32 seg_len, struct page *p)
+{
+ struct sk_buff *skb;
+ struct mt76x0_rxwi *rxwi;
+ u32 fce_info, truesize = seg_len;
+
+ /* DMA_INFO field at the beginning of the segment contains only some of
+ * the information, we need to read the FCE descriptor from the end.
+ */
+ fce_info = get_unaligned_le32(data + seg_len - MT_FCE_INFO_LEN);
+ seg_len -= MT_FCE_INFO_LEN;
+
+ data += MT_DMA_HDR_LEN;
+ seg_len -= MT_DMA_HDR_LEN;
+
+ rxwi = (struct mt76x0_rxwi *) data;
+ data += sizeof(struct mt76x0_rxwi);
+ seg_len -= sizeof(struct mt76x0_rxwi);
+
+ if (unlikely(FIELD_GET(MT_RXD_INFO_TYPE, fce_info)))
+ dev_err_once(dev->mt76.dev, "Error: RX path seen a non-pkt urb\n");
+#if LINUX_VERSION_IS_GEQ(3,12,0)
+ trace_mt76x0_rx(&dev->mt76, rxwi, fce_info);
+#endif
+
+ skb = mt76x0_rx_skb_from_seg(dev, rxwi, data, seg_len, truesize, p);
+ if (!skb)
+ return;
+
+ spin_lock(&dev->mac_lock);
+ ieee80211_rx(dev->mt76.hw, skb);
+ spin_unlock(&dev->mac_lock);
+}
+
+static u16 mt76x0_rx_next_seg_len(u8 *data, u32 data_len)
+{
+ u32 min_seg_len = MT_DMA_HDR_LEN + MT_RX_INFO_LEN +
+ sizeof(struct mt76x0_rxwi) + MT_FCE_INFO_LEN;
+ u16 dma_len = get_unaligned_le16(data);
+
+ if (data_len < min_seg_len ||
+ WARN_ON(!dma_len) ||
+ WARN_ON(dma_len + MT_DMA_HDRS > data_len) ||
+ WARN_ON(dma_len & 0x3))
+ return 0;
+
+ return MT_DMA_HDRS + dma_len;
+}
+
+static void
+mt76x0_rx_process_entry(struct mt76x0_dev *dev, struct mt76x0_dma_buf_rx *e)
+{
+ u32 seg_len, data_len = e->urb->actual_length;
+ u8 *data = page_address(e->p);
+ struct page *new_p = NULL;
+ int cnt = 0;
+
+ if (!test_bit(MT76_STATE_INITIALIZED, &dev->mt76.state))
+ return;
+
+ /* Copy if there is very little data in the buffer. */
+ if (data_len > 512)
+ new_p = dev_alloc_pages(MT_RX_ORDER);
+
+ while ((seg_len = mt76x0_rx_next_seg_len(data, data_len))) {
+ mt76x0_rx_process_seg(dev, data, seg_len, new_p ? e->p : NULL);
+
+ data_len -= seg_len;
+ data += seg_len;
+ cnt++;
+ }
+
+#if LINUX_VERSION_IS_GEQ(3,12,0)
+ if (cnt > 1)
+ trace_mt76x0_rx_dma_aggr(&dev->mt76, cnt, !!new_p);
+#endif
+
+ if (new_p) {
+ /* we have one extra ref from the allocator */
+ __free_pages(e->p, MT_RX_ORDER);
+
+ e->p = new_p;
+ }
+}
+
+static struct mt76x0_dma_buf_rx *
+mt76x0_rx_get_pending_entry(struct mt76x0_dev *dev)
+{
+ struct mt76x0_rx_queue *q = &dev->rx_q;
+ struct mt76x0_dma_buf_rx *buf = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->rx_lock, flags);
+
+ if (!q->pending)
+ goto out;
+
+ buf = &q->e[q->start];
+ q->pending--;
+ q->start = (q->start + 1) % q->entries;
+out:
+ spin_unlock_irqrestore(&dev->rx_lock, flags);
+
+ return buf;
+}
+
+static void mt76x0_complete_rx(struct urb *urb)
+{
+ struct mt76x0_dev *dev = urb->context;
+ struct mt76x0_rx_queue *q = &dev->rx_q;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->rx_lock, flags);
+
+ if (mt76x0_urb_has_error(urb))
+ dev_err(dev->mt76.dev, "Error: RX urb failed:%d\n", urb->status);
+ if (WARN_ONCE(q->e[q->end].urb != urb, "RX urb mismatch"))
+ goto out;
+
+ q->end = (q->end + 1) % q->entries;
+ q->pending++;
+ tasklet_schedule(&dev->rx_tasklet);
+out:
+ spin_unlock_irqrestore(&dev->rx_lock, flags);
+}
+
+static void mt76x0_rx_tasklet(unsigned long data)
+{
+ struct mt76x0_dev *dev = (struct mt76x0_dev *) data;
+ struct mt76x0_dma_buf_rx *e;
+
+ while ((e = mt76x0_rx_get_pending_entry(dev))) {
+ if (e->urb->status)
+ continue;
+
+ mt76x0_rx_process_entry(dev, e);
+ mt76x0_submit_rx_buf(dev, e, GFP_ATOMIC);
+ }
+}
+
+static void mt76x0_complete_tx(struct urb *urb)
+{
+ struct mt76x0_tx_queue *q = urb->context;
+ struct mt76x0_dev *dev = q->dev;
+ struct sk_buff *skb;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->tx_lock, flags);
+
+ if (mt76x0_urb_has_error(urb))
+ dev_err(dev->mt76.dev, "Error: TX urb failed:%d\n", urb->status);
+ if (WARN_ONCE(q->e[q->start].urb != urb, "TX urb mismatch"))
+ goto out;
+
+ skb = q->e[q->start].skb;
+#if LINUX_VERSION_IS_GEQ(3,12,0)
+ trace_mt76x0_tx_dma_done(&dev->mt76, skb);
+#endif
+
+ __skb_queue_tail(&dev->tx_skb_done, skb);
+ tasklet_schedule(&dev->tx_tasklet);
+
+ if (q->used == q->entries - q->entries / 8)
+ ieee80211_wake_queue(dev->mt76.hw, skb_get_queue_mapping(skb));
+
+ q->start = (q->start + 1) % q->entries;
+ q->used--;
+out:
+ spin_unlock_irqrestore(&dev->tx_lock, flags);
+}
+
+static void mt76x0_tx_tasklet(unsigned long data)
+{
+ struct mt76x0_dev *dev = (struct mt76x0_dev *) data;
+ struct sk_buff_head skbs;
+ unsigned long flags;
+
+ __skb_queue_head_init(&skbs);
+
+ spin_lock_irqsave(&dev->tx_lock, flags);
+
+ set_bit(MT76_MORE_STATS, &dev->mt76.state);
+ if (!test_and_set_bit(MT76_READING_STATS, &dev->mt76.state))
+ queue_delayed_work(dev->stat_wq, &dev->stat_work,
+ msecs_to_jiffies(10));
+
+ skb_queue_splice_init(&dev->tx_skb_done, &skbs);
+
+ spin_unlock_irqrestore(&dev->tx_lock, flags);
+
+ while (!skb_queue_empty(&skbs)) {
+ struct sk_buff *skb = __skb_dequeue(&skbs);
+
+ mt76x0_tx_status(dev, skb);
+ }
+}
+
+static int mt76x0_dma_submit_tx(struct mt76x0_dev *dev,
+ struct sk_buff *skb, u8 ep)
+{
+ struct usb_device *usb_dev = mt76x0_to_usb_dev(dev);
+ unsigned snd_pipe = usb_sndbulkpipe(usb_dev, dev->out_ep[ep]);
+ struct mt76x0_dma_buf_tx *e;
+ struct mt76x0_tx_queue *q = &dev->tx_q[ep];
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&dev->tx_lock, flags);
+
+ if (WARN_ON_ONCE(q->entries <= q->used)) {
+ ret = -ENOSPC;
+ goto out;
+ }
+
+ e = &q->e[q->end];
+ e->skb = skb;
+ usb_fill_bulk_urb(e->urb, usb_dev, snd_pipe, skb->data, skb->len,
+ mt76x0_complete_tx, q);
+ ret = usb_submit_urb(e->urb, GFP_ATOMIC);
+ if (ret) {
+ /* Special-handle ENODEV from TX urb submission because it will
+ * often be the first ENODEV we see after device is removed.
+ */
+ if (ret == -ENODEV)
+ set_bit(MT76_REMOVED, &dev->mt76.state);
+ else
+ dev_err(dev->mt76.dev, "Error: TX urb submit failed:%d\n",
+ ret);
+ goto out;
+ }
+
+ q->end = (q->end + 1) % q->entries;
+ q->used++;
+
+ if (q->used >= q->entries)
+ ieee80211_stop_queue(dev->mt76.hw, skb_get_queue_mapping(skb));
+out:
+ spin_unlock_irqrestore(&dev->tx_lock, flags);
+
+ return ret;
+}
+
+/* Map USB endpoint number to Q id in the DMA engine */
+static enum mt76_qsel ep2dmaq(u8 ep)
+{
+ if (ep == 5)
+ return MT_QSEL_MGMT;
+ return MT_QSEL_EDCA;
+}
+
+int mt76x0_dma_enqueue_tx(struct mt76x0_dev *dev, struct sk_buff *skb,
+ struct mt76_wcid *wcid, int hw_q)
+{
+ u8 ep = q2ep(hw_q);
+ u32 dma_flags;
+ int ret;
+
+ dma_flags = MT_TXD_PKT_INFO_80211;
+ if (wcid->hw_key_idx == 0xff)
+ dma_flags |= MT_TXD_PKT_INFO_WIV;
+
+ ret = mt76x0_dma_skb_wrap_pkt(skb, ep2dmaq(ep), dma_flags);
+ if (ret)
+ return ret;
+
+ ret = mt76x0_dma_submit_tx(dev, skb, ep);
+
+ if (ret) {
+ ieee80211_free_txskb(dev->mt76.hw, skb);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void mt76x0_kill_rx(struct mt76x0_dev *dev)
+{
+ int i;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->rx_lock, flags);
+
+ for (i = 0; i < dev->rx_q.entries; i++) {
+ int next = dev->rx_q.end;
+
+ spin_unlock_irqrestore(&dev->rx_lock, flags);
+ usb_poison_urb(dev->rx_q.e[next].urb);
+ spin_lock_irqsave(&dev->rx_lock, flags);
+ }
+
+ spin_unlock_irqrestore(&dev->rx_lock, flags);
+}
+
+static int mt76x0_submit_rx_buf(struct mt76x0_dev *dev,
+ struct mt76x0_dma_buf_rx *e, gfp_t gfp)
+{
+ struct usb_device *usb_dev = mt76x0_to_usb_dev(dev);
+ u8 *buf = page_address(e->p);
+ unsigned pipe;
+ int ret;
+
+ pipe = usb_rcvbulkpipe(usb_dev, dev->in_ep[MT_EP_IN_PKT_RX]);
+
+ usb_fill_bulk_urb(e->urb, usb_dev, pipe, buf, MT_RX_URB_SIZE,
+ mt76x0_complete_rx, dev);
+#if LINUX_VERSION_IS_GEQ(3,12,0)
+ trace_mt76x0_submit_urb(&dev->mt76, e->urb);
+#endif
+ ret = usb_submit_urb(e->urb, gfp);
+ if (ret)
+ dev_err(dev->mt76.dev, "Error: submit RX URB failed:%d\n", ret);
+
+ return ret;
+}
+
+static int mt76x0_submit_rx(struct mt76x0_dev *dev)
+{
+ int i, ret;
+
+ for (i = 0; i < dev->rx_q.entries; i++) {
+ ret = mt76x0_submit_rx_buf(dev, &dev->rx_q.e[i], GFP_KERNEL);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static void mt76x0_free_rx(struct mt76x0_dev *dev)
+{
+ int i;
+
+ for (i = 0; i < dev->rx_q.entries; i++) {
+ __free_pages(dev->rx_q.e[i].p, MT_RX_ORDER);
+ usb_free_urb(dev->rx_q.e[i].urb);
+ }
+}
+
+static int mt76x0_alloc_rx(struct mt76x0_dev *dev)
+{
+ int i;
+
+ memset(&dev->rx_q, 0, sizeof(dev->rx_q));
+ dev->rx_q.dev = dev;
+ dev->rx_q.entries = N_RX_ENTRIES;
+
+ for (i = 0; i < N_RX_ENTRIES; i++) {
+ dev->rx_q.e[i].urb = usb_alloc_urb(0, GFP_KERNEL);
+ dev->rx_q.e[i].p = dev_alloc_pages(MT_RX_ORDER);
+
+ if (!dev->rx_q.e[i].urb || !dev->rx_q.e[i].p)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void mt76x0_free_tx_queue(struct mt76x0_tx_queue *q)
+{
+ int i;
+
+ WARN_ON(q->used);
+
+ for (i = 0; i < q->entries; i++) {
+ usb_poison_urb(q->e[i].urb);
+ usb_free_urb(q->e[i].urb);
+ }
+}
+
+static void mt76x0_free_tx(struct mt76x0_dev *dev)
+{
+ int i;
+
+ for (i = 0; i < __MT_EP_OUT_MAX; i++)
+ mt76x0_free_tx_queue(&dev->tx_q[i]);
+}
+
+static int mt76x0_alloc_tx_queue(struct mt76x0_dev *dev,
+ struct mt76x0_tx_queue *q)
+{
+ int i;
+
+ q->dev = dev;
+ q->entries = N_TX_ENTRIES;
+
+ for (i = 0; i < N_TX_ENTRIES; i++) {
+ q->e[i].urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!q->e[i].urb)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int mt76x0_alloc_tx(struct mt76x0_dev *dev)
+{
+ int i;
+
+ dev->tx_q = devm_kcalloc(dev->mt76.dev, __MT_EP_OUT_MAX,
+ sizeof(*dev->tx_q), GFP_KERNEL);
+
+ for (i = 0; i < __MT_EP_OUT_MAX; i++)
+ if (mt76x0_alloc_tx_queue(dev, &dev->tx_q[i]))
+ return -ENOMEM;
+
+ return 0;
+}
+
+int mt76x0_dma_init(struct mt76x0_dev *dev)
+{
+ int ret = -ENOMEM;
+
+ tasklet_init(&dev->tx_tasklet, mt76x0_tx_tasklet, (unsigned long) dev);
+ tasklet_init(&dev->rx_tasklet, mt76x0_rx_tasklet, (unsigned long) dev);
+
+ ret = mt76x0_alloc_tx(dev);
+ if (ret)
+ goto err;
+ ret = mt76x0_alloc_rx(dev);
+ if (ret)
+ goto err;
+
+ ret = mt76x0_submit_rx(dev);
+ if (ret)
+ goto err;
+
+ return 0;
+err:
+ mt76x0_dma_cleanup(dev);
+ return ret;
+}
+
+void mt76x0_dma_cleanup(struct mt76x0_dev *dev)
+{
+ mt76x0_kill_rx(dev);
+
+ tasklet_kill(&dev->rx_tasklet);
+
+ mt76x0_free_rx(dev);
+ mt76x0_free_tx(dev);
+
+ tasklet_kill(&dev->tx_tasklet);
+}