diff options
Diffstat (limited to 'drivers/net/wireless/mediatek/mt7601u/dma.c')
-rw-r--r-- | drivers/net/wireless/mediatek/mt7601u/dma.c | 551 |
1 files changed, 551 insertions, 0 deletions
diff --git a/drivers/net/wireless/mediatek/mt7601u/dma.c b/drivers/net/wireless/mediatek/mt7601u/dma.c new file mode 100644 index 000000000..773a1cc2f --- /dev/null +++ b/drivers/net/wireless/mediatek/mt7601u/dma.c @@ -0,0 +1,551 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2015 Jakub Kicinski <kubakici@wp.pl> + */ + +#include "mt7601u.h" +#include "dma.h" +#include "usb.h" +#include "trace.h" + +static int mt7601u_submit_rx_buf(struct mt7601u_dev *dev, + struct mt7601u_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 * +mt7601u_rx_skb_from_seg(struct mt7601u_dev *dev, struct mt7601u_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 = mt76_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)) { + skb_put_data(skb, 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; + + skb_put_data(skb, 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->dev, "Error: incorrect frame len:%u hdr:%u\n", + true_len, hdr_len); + dev_kfree_skb(skb); + return NULL; +} + +static void mt7601u_rx_process_seg(struct mt7601u_dev *dev, u8 *data, + u32 seg_len, struct page *p, + struct list_head *list) +{ + struct sk_buff *skb; + struct mt7601u_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 mt7601u_rxwi *) data; + data += sizeof(struct mt7601u_rxwi); + seg_len -= sizeof(struct mt7601u_rxwi); + + if (unlikely(rxwi->zero[0] || rxwi->zero[1] || rxwi->zero[2])) + dev_err_once(dev->dev, "Error: RXWI zero fields are set\n"); + if (unlikely(FIELD_GET(MT_RXD_INFO_TYPE, fce_info))) + dev_err_once(dev->dev, "Error: RX path seen a non-pkt urb\n"); + + trace_mt_rx(dev, rxwi, fce_info); + + skb = mt7601u_rx_skb_from_seg(dev, rxwi, data, seg_len, truesize, p); + if (!skb) + return; + + local_bh_disable(); + rcu_read_lock(); + + ieee80211_rx_list(dev->hw, NULL, skb, list); + + rcu_read_unlock(); + local_bh_enable(); +} + +static u16 mt7601u_rx_next_seg_len(u8 *data, u32 data_len) +{ + u32 min_seg_len = MT_DMA_HDR_LEN + MT_RX_INFO_LEN + + sizeof(struct mt7601u_rxwi) + MT_FCE_INFO_LEN; + u16 dma_len = get_unaligned_le16(data); + + if (data_len < min_seg_len || + WARN_ON_ONCE(!dma_len) || + WARN_ON_ONCE(dma_len + MT_DMA_HDRS > data_len) || + WARN_ON_ONCE(dma_len & 0x3) || + WARN_ON_ONCE(dma_len < min_seg_len)) + return 0; + + return MT_DMA_HDRS + dma_len; +} + +static void +mt7601u_rx_process_entry(struct mt7601u_dev *dev, struct mt7601u_dma_buf_rx *e) +{ + u32 seg_len, data_len = e->urb->actual_length; + u8 *data = page_address(e->p); + struct page *new_p = NULL; + LIST_HEAD(list); + int cnt = 0; + + if (!test_bit(MT7601U_STATE_INITIALIZED, &dev->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 = mt7601u_rx_next_seg_len(data, data_len))) { + mt7601u_rx_process_seg(dev, data, seg_len, + new_p ? e->p : NULL, &list); + + data_len -= seg_len; + data += seg_len; + cnt++; + } + + if (cnt > 1) + trace_mt_rx_dma_aggr(dev, cnt, !!new_p); + + netif_receive_skb_list(&list); + + if (new_p) { + /* we have one extra ref from the allocator */ + put_page(e->p); + e->p = new_p; + } +} + +static struct mt7601u_dma_buf_rx * +mt7601u_rx_get_pending_entry(struct mt7601u_dev *dev) +{ + struct mt7601u_rx_queue *q = &dev->rx_q; + struct mt7601u_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 mt7601u_complete_rx(struct urb *urb) +{ + struct mt7601u_dev *dev = urb->context; + struct mt7601u_rx_queue *q = &dev->rx_q; + unsigned long flags; + + /* do no schedule rx tasklet if urb has been unlinked + * or the device has been removed + */ + switch (urb->status) { + case -ECONNRESET: + case -ESHUTDOWN: + case -ENOENT: + case -EPROTO: + return; + default: + dev_err_ratelimited(dev->dev, "rx urb failed: %d\n", + urb->status); + fallthrough; + case 0: + break; + } + + spin_lock_irqsave(&dev->rx_lock, flags); + 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 mt7601u_rx_tasklet(struct tasklet_struct *t) +{ + struct mt7601u_dev *dev = from_tasklet(dev, t, rx_tasklet); + struct mt7601u_dma_buf_rx *e; + + while ((e = mt7601u_rx_get_pending_entry(dev))) { + if (e->urb->status) + continue; + + mt7601u_rx_process_entry(dev, e); + mt7601u_submit_rx_buf(dev, e, GFP_ATOMIC); + } +} + +static void mt7601u_complete_tx(struct urb *urb) +{ + struct mt7601u_tx_queue *q = urb->context; + struct mt7601u_dev *dev = q->dev; + struct sk_buff *skb; + unsigned long flags; + + switch (urb->status) { + case -ECONNRESET: + case -ESHUTDOWN: + case -ENOENT: + case -EPROTO: + return; + default: + dev_err_ratelimited(dev->dev, "tx urb failed: %d\n", + urb->status); + fallthrough; + case 0: + break; + } + + spin_lock_irqsave(&dev->tx_lock, flags); + if (WARN_ONCE(q->e[q->start].urb != urb, "TX urb mismatch")) + goto out; + + skb = q->e[q->start].skb; + q->e[q->start].skb = NULL; + trace_mt_tx_dma_done(dev, skb); + + __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->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 mt7601u_tx_tasklet(struct tasklet_struct *t) +{ + struct mt7601u_dev *dev = from_tasklet(dev, t, tx_tasklet); + struct sk_buff_head skbs; + unsigned long flags; + + __skb_queue_head_init(&skbs); + + spin_lock_irqsave(&dev->tx_lock, flags); + + set_bit(MT7601U_STATE_MORE_STATS, &dev->state); + if (!test_and_set_bit(MT7601U_STATE_READING_STATS, &dev->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); + + mt7601u_tx_status(dev, skb); + } +} + +static int mt7601u_dma_submit_tx(struct mt7601u_dev *dev, + struct sk_buff *skb, u8 ep) +{ + struct usb_device *usb_dev = mt7601u_to_usb_dev(dev); + unsigned snd_pipe = usb_sndbulkpipe(usb_dev, dev->out_eps[ep]); + struct mt7601u_dma_buf_tx *e; + struct mt7601u_tx_queue *q = &dev->tx_q[ep]; + unsigned long flags; + int ret; + + spin_lock_irqsave(&dev->tx_lock, flags); + + if (WARN_ON(q->entries <= q->used)) { + ret = -ENOSPC; + goto out; + } + + e = &q->e[q->end]; + usb_fill_bulk_urb(e->urb, usb_dev, snd_pipe, skb->data, skb->len, + mt7601u_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(MT7601U_STATE_REMOVED, &dev->state); + else + dev_err(dev->dev, "Error: TX urb submit failed:%d\n", + ret); + goto out; + } + + q->end = (q->end + 1) % q->entries; + q->used++; + e->skb = skb; + + if (q->used >= q->entries) + ieee80211_stop_queue(dev->hw, skb_get_queue_mapping(skb)); +out: + spin_unlock_irqrestore(&dev->tx_lock, flags); + + return ret; +} + +/* Map hardware Q to USB endpoint number */ +static u8 q2ep(u8 qid) +{ + /* TODO: take management packets to queue 5 */ + return qid + 1; +} + +/* 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 mt7601u_dma_enqueue_tx(struct mt7601u_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 = mt7601u_dma_skb_wrap_pkt(skb, ep2dmaq(ep), dma_flags); + if (ret) + return ret; + + ret = mt7601u_dma_submit_tx(dev, skb, ep); + if (ret) { + ieee80211_free_txskb(dev->hw, skb); + return ret; + } + + return 0; +} + +static void mt7601u_kill_rx(struct mt7601u_dev *dev) +{ + int i; + + for (i = 0; i < dev->rx_q.entries; i++) + usb_poison_urb(dev->rx_q.e[i].urb); +} + +static int mt7601u_submit_rx_buf(struct mt7601u_dev *dev, + struct mt7601u_dma_buf_rx *e, gfp_t gfp) +{ + struct usb_device *usb_dev = mt7601u_to_usb_dev(dev); + u8 *buf = page_address(e->p); + unsigned pipe; + int ret; + + pipe = usb_rcvbulkpipe(usb_dev, dev->in_eps[MT_EP_IN_PKT_RX]); + + usb_fill_bulk_urb(e->urb, usb_dev, pipe, buf, MT_RX_URB_SIZE, + mt7601u_complete_rx, dev); + + trace_mt_submit_urb(dev, e->urb); + ret = usb_submit_urb(e->urb, gfp); + if (ret) + dev_err(dev->dev, "Error: submit RX URB failed:%d\n", ret); + + return ret; +} + +static int mt7601u_submit_rx(struct mt7601u_dev *dev) +{ + int i, ret; + + for (i = 0; i < dev->rx_q.entries; i++) { + ret = mt7601u_submit_rx_buf(dev, &dev->rx_q.e[i], GFP_KERNEL); + if (ret) + return ret; + } + + return 0; +} + +static void mt7601u_free_rx(struct mt7601u_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 mt7601u_alloc_rx(struct mt7601u_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 mt7601u_free_tx_queue(struct mt7601u_tx_queue *q) +{ + int i; + + for (i = 0; i < q->entries; i++) { + usb_poison_urb(q->e[i].urb); + if (q->e[i].skb) + mt7601u_tx_status(q->dev, q->e[i].skb); + usb_free_urb(q->e[i].urb); + } +} + +static void mt7601u_free_tx(struct mt7601u_dev *dev) +{ + int i; + + if (!dev->tx_q) + return; + + for (i = 0; i < __MT_EP_OUT_MAX; i++) + mt7601u_free_tx_queue(&dev->tx_q[i]); +} + +static int mt7601u_alloc_tx_queue(struct mt7601u_dev *dev, + struct mt7601u_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 mt7601u_alloc_tx(struct mt7601u_dev *dev) +{ + int i; + + dev->tx_q = devm_kcalloc(dev->dev, __MT_EP_OUT_MAX, + sizeof(*dev->tx_q), GFP_KERNEL); + if (!dev->tx_q) + return -ENOMEM; + + for (i = 0; i < __MT_EP_OUT_MAX; i++) + if (mt7601u_alloc_tx_queue(dev, &dev->tx_q[i])) + return -ENOMEM; + + return 0; +} + +int mt7601u_dma_init(struct mt7601u_dev *dev) +{ + int ret; + + tasklet_setup(&dev->tx_tasklet, mt7601u_tx_tasklet); + tasklet_setup(&dev->rx_tasklet, mt7601u_rx_tasklet); + + ret = mt7601u_alloc_tx(dev); + if (ret) + goto err; + ret = mt7601u_alloc_rx(dev); + if (ret) + goto err; + + ret = mt7601u_submit_rx(dev); + if (ret) + goto err; + + return 0; +err: + mt7601u_dma_cleanup(dev); + return ret; +} + +void mt7601u_dma_cleanup(struct mt7601u_dev *dev) +{ + mt7601u_kill_rx(dev); + + tasklet_kill(&dev->rx_tasklet); + + mt7601u_free_rx(dev); + mt7601u_free_tx(dev); + + tasklet_kill(&dev->tx_tasklet); +} |