mt76: introduce mt76_sdio module

Introduce mt76_sdio module as common layer to add mt7663s support

Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

1 files changed, 363 insertions, 0 deletions

diff --git a/drivers/net/wireless/mediatek/mt76/sdio.c b/drivers/net/wireless/mediatek/mt76/sdio.c
new file mode 100644
index 000000000000..a6f3255c4d84
--- /dev/null
+++ b/drivers/net/wireless/mediatek/mt76/sdio.c
@@ -0,0 +1,363 @@
+// SPDX-License-Identifier: ISC
+/* Copyright (C) 2020 MediaTek Inc.
+ *
+ * This file is written based on mt76/usb.c.
+ *
+ * Author: Felix Fietkau <nbd@nbd.name>
+ *	   Lorenzo Bianconi <lorenzo@kernel.org>
+ *	   Sean Wang <sean.wang@mediatek.com>
+ */
+
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mmc/sdio_func.h>
+#include <linux/sched.h>
+#include <linux/kthread.h>
+
+#include "mt76.h"
+
+static int
+mt76s_alloc_rx_queue(struct mt76_dev *dev, enum mt76_rxq_id qid)
+{
+	struct mt76_queue *q = &dev->q_rx[qid];
+
+	spin_lock_init(&q->lock);
+	q->entry = devm_kcalloc(dev->dev,
+				MT_NUM_RX_ENTRIES, sizeof(*q->entry),
+				GFP_KERNEL);
+	if (!q->entry)
+		return -ENOMEM;
+
+	q->ndesc = MT_NUM_RX_ENTRIES;
+	q->head = q->tail = 0;
+	q->queued = 0;
+
+	return 0;
+}
+
+static int mt76s_alloc_tx(struct mt76_dev *dev)
+{
+	struct mt76_queue *q;
+	int i;
+
+	for (i = 0; i < MT_TXQ_MCU_WA; i++) {
+		INIT_LIST_HEAD(&dev->q_tx[i].swq);
+
+		q = devm_kzalloc(dev->dev, sizeof(*q), GFP_KERNEL);
+		if (!q)
+			return -ENOMEM;
+
+		spin_lock_init(&q->lock);
+		q->hw_idx = i;
+		dev->q_tx[i].q = q;
+
+		q->entry = devm_kcalloc(dev->dev,
+					MT_NUM_TX_ENTRIES, sizeof(*q->entry),
+					GFP_KERNEL);
+		if (!q->entry)
+			return -ENOMEM;
+
+		q->ndesc = MT_NUM_TX_ENTRIES;
+	}
+
+	return 0;
+}
+
+void mt76s_stop_txrx(struct mt76_dev *dev)
+{
+	struct mt76_sdio *sdio = &dev->sdio;
+
+	cancel_work_sync(&sdio->stat_work);
+	clear_bit(MT76_READING_STATS, &dev->phy.state);
+
+	mt76_tx_status_check(dev, NULL, true);
+}
+EXPORT_SYMBOL_GPL(mt76s_stop_txrx);
+
+int mt76s_alloc_queues(struct mt76_dev *dev)
+{
+	int err;
+
+	err = mt76s_alloc_rx_queue(dev, MT_RXQ_MAIN);
+	if (err < 0)
+		return err;
+
+	return mt76s_alloc_tx(dev);
+}
+EXPORT_SYMBOL_GPL(mt76s_alloc_queues);
+
+static struct mt76_queue_entry *
+mt76s_get_next_rx_entry(struct mt76_queue *q)
+{
+	struct mt76_queue_entry *e = NULL;
+
+	spin_lock_bh(&q->lock);
+	if (q->queued > 0) {
+		e = &q->entry[q->head];
+		q->head = (q->head + 1) % q->ndesc;
+		q->queued--;
+	}
+	spin_unlock_bh(&q->lock);
+
+	return e;
+}
+
+static int
+mt76s_process_rx_queue(struct mt76_dev *dev, struct mt76_queue *q)
+{
+	int qid = q - &dev->q_rx[MT_RXQ_MAIN];
+	int nframes = 0;
+
+	while (true) {
+		struct mt76_queue_entry *e;
+
+		if (!test_bit(MT76_STATE_INITIALIZED, &dev->phy.state))
+			break;
+
+		e = mt76s_get_next_rx_entry(q);
+		if (!e || !e->skb)
+			break;
+
+		dev->drv->rx_skb(dev, MT_RXQ_MAIN, e->skb);
+		e->skb = NULL;
+		nframes++;
+	}
+	if (qid == MT_RXQ_MAIN)
+		mt76_rx_poll_complete(dev, MT_RXQ_MAIN, NULL);
+
+	return nframes;
+}
+
+static int mt76s_process_tx_queue(struct mt76_dev *dev, enum mt76_txq_id qid)
+{
+	struct mt76_sw_queue *sq = &dev->q_tx[qid];
+	u32 n_dequeued = 0, n_sw_dequeued = 0;
+	struct mt76_queue_entry entry;
+	struct mt76_queue *q = sq->q;
+	bool wake;
+
+	while (q->queued > n_dequeued) {
+		if (q->entry[q->head].schedule) {
+			q->entry[q->head].schedule = false;
+			n_sw_dequeued++;
+		}
+
+		entry = q->entry[q->head];
+		q->entry[q->head].done = false;
+		q->head = (q->head + 1) % q->ndesc;
+		n_dequeued++;
+
+		if (qid == MT_TXQ_MCU)
+			dev_kfree_skb(entry.skb);
+		else
+			dev->drv->tx_complete_skb(dev, qid, &entry);
+	}
+
+	spin_lock_bh(&q->lock);
+
+	sq->swq_queued -= n_sw_dequeued;
+	q->queued -= n_dequeued;
+
+	wake = q->stopped && q->queued < q->ndesc - 8;
+	if (wake)
+		q->stopped = false;
+
+	if (!q->queued)
+		wake_up(&dev->tx_wait);
+
+	spin_unlock_bh(&q->lock);
+
+	if (qid == MT_TXQ_MCU)
+		goto out;
+
+	mt76_txq_schedule(&dev->phy, qid);
+
+	if (wake)
+		ieee80211_wake_queue(dev->hw, qid);
+
+	wake_up_process(dev->sdio.tx_kthread);
+out:
+	return n_dequeued;
+}
+
+static void mt76s_tx_status_data(struct work_struct *work)
+{
+	struct mt76_sdio *sdio;
+	struct mt76_dev *dev;
+	u8 update = 1;
+	u16 count = 0;
+
+	sdio = container_of(work, struct mt76_sdio, stat_work);
+	dev = container_of(sdio, struct mt76_dev, sdio);
+
+	while (true) {
+		if (test_bit(MT76_REMOVED, &dev->phy.state))
+			break;
+
+		if (!dev->drv->tx_status_data(dev, &update))
+			break;
+		count++;
+	}
+
+	if (count && test_bit(MT76_STATE_RUNNING, &dev->phy.state))
+		queue_work(dev->wq, &sdio->stat_work);
+	else
+		clear_bit(MT76_READING_STATS, &dev->phy.state);
+}
+
+static int
+mt76s_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid,
+		   struct sk_buff *skb, struct mt76_wcid *wcid,
+		   struct ieee80211_sta *sta)
+{
+	struct mt76_queue *q = dev->q_tx[qid].q;
+	struct mt76_tx_info tx_info = {
+		.skb = skb,
+	};
+	int err, len = skb->len;
+	u16 idx = q->tail;
+
+	if (q->queued == q->ndesc)
+		return -ENOSPC;
+
+	skb->prev = skb->next = NULL;
+	err = dev->drv->tx_prepare_skb(dev, NULL, qid, wcid, sta, &tx_info);
+	if (err < 0)
+		return err;
+
+	q->entry[q->tail].skb = tx_info.skb;
+	q->entry[q->tail].buf_sz = len;
+	q->tail = (q->tail + 1) % q->ndesc;
+
+	return idx;
+}
+
+static int
+mt76s_tx_queue_skb_raw(struct mt76_dev *dev, enum mt76_txq_id qid,
+		       struct sk_buff *skb, u32 tx_info)
+{
+	struct mt76_queue *q = dev->q_tx[qid].q;
+	int ret = -ENOSPC, len = skb->len;
+
+	spin_lock_bh(&q->lock);
+	if (q->queued == q->ndesc)
+		goto out;
+
+	ret = mt76_skb_adjust_pad(skb);
+	if (ret)
+		goto out;
+
+	q->entry[q->tail].buf_sz = len;
+	q->entry[q->tail].skb = skb;
+	q->tail = (q->tail + 1) % q->ndesc;
+
+out:
+	spin_unlock_bh(&q->lock);
+
+	return ret;
+}
+
+static void mt76s_tx_kick(struct mt76_dev *dev, struct mt76_queue *q)
+{
+	struct mt76_sdio *sdio = &dev->sdio;
+
+	wake_up_process(sdio->tx_kthread);
+}
+
+static const struct mt76_queue_ops sdio_queue_ops = {
+	.tx_queue_skb = mt76s_tx_queue_skb,
+	.kick = mt76s_tx_kick,
+	.tx_queue_skb_raw = mt76s_tx_queue_skb_raw,
+};
+
+static int mt76s_kthread_run(void *data)
+{
+	struct mt76_dev *dev = data;
+	struct mt76_phy *mphy = &dev->phy;
+
+	while (!kthread_should_stop()) {
+		int i, nframes = 0;
+
+		cond_resched();
+
+		/* rx processing */
+		local_bh_disable();
+		rcu_read_lock();
+
+		mt76_for_each_q_rx(dev, i)
+			nframes += mt76s_process_rx_queue(dev, &dev->q_rx[i]);
+
+		rcu_read_unlock();
+		local_bh_enable();
+
+		/* tx processing */
+		for (i = 0; i < MT_TXQ_MCU_WA; i++)
+			nframes += mt76s_process_tx_queue(dev, i);
+
+		if (dev->drv->tx_status_data &&
+		    !test_and_set_bit(MT76_READING_STATS, &mphy->state))
+			queue_work(dev->wq, &dev->sdio.stat_work);
+
+		if (!nframes || !test_bit(MT76_STATE_RUNNING, &mphy->state)) {
+			set_current_state(TASK_INTERRUPTIBLE);
+			schedule();
+		}
+	}
+
+	return 0;
+}
+
+void mt76s_deinit(struct mt76_dev *dev)
+{
+	struct mt76_sdio *sdio = &dev->sdio;
+	int i;
+
+	kthread_stop(sdio->kthread);
+	kthread_stop(sdio->tx_kthread);
+	mt76s_stop_txrx(dev);
+
+	sdio_claim_host(sdio->func);
+	sdio_release_irq(sdio->func);
+	sdio_release_host(sdio->func);
+
+	mt76_for_each_q_rx(dev, i) {
+		struct mt76_queue *q = &dev->q_rx[i];
+		int j;
+
+		for (j = 0; j < q->ndesc; j++) {
+			struct mt76_queue_entry *e = &q->entry[j];
+
+			if (!e->skb)
+				continue;
+
+			dev_kfree_skb(e->skb);
+			e->skb = NULL;
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(mt76s_deinit);
+
+int mt76s_init(struct mt76_dev *dev, struct sdio_func *func,
+	       const struct mt76_bus_ops *bus_ops)
+{
+	struct mt76_sdio *sdio = &dev->sdio;
+
+	sdio->kthread = kthread_create(mt76s_kthread_run, dev, "mt76s");
+	if (IS_ERR(sdio->kthread))
+		return PTR_ERR(sdio->kthread);
+
+	INIT_WORK(&sdio->stat_work, mt76s_tx_status_data);
+
+	mutex_init(&sdio->sched.lock);
+	dev->queue_ops = &sdio_queue_ops;
+	dev->bus = bus_ops;
+	dev->sdio.func = func;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mt76s_init);
+
+MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
+MODULE_AUTHOR("Lorenzo Bianconi <lorenzo@kernel.org>");
+MODULE_LICENSE("Dual BSD/GPL");