[PATCH v2 16/16] mt76: mt7921s: add reset support

sean.wang
2021-09-18T00:10:23Z

Introduce wifi chip reset support for mt7921 device to recover
mcu hangs or abnormal wifi system.

Tested-by: Deren Wu <deren.wu@mediatek.com>
Co-developed-by: Deren Wu <deren.wu@mediatek.com>
Signed-off-by: Deren Wu <deren.wu@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
drivers/net/wireless/mediatek/mt76/mt76.h | 2 +
.../net/wireless/mediatek/mt76/mt7921/init.c | 2 +
.../net/wireless/mediatek/mt76/mt7921/mcu.c | 1 +
.../wireless/mediatek/mt76/mt7921/mt7921.h | 4 +
.../net/wireless/mediatek/mt76/mt7921/sdio.c | 3 +
.../wireless/mediatek/mt76/mt7921/sdio_mac.c | 133 ++++++++++++++++++
.../wireless/mediatek/mt76/mt7921/sdio_mcu.c | 8 ++
.../net/wireless/mediatek/mt76/sdio_txrx.c | 32 ++++-
8 files changed, 184 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
index 50743a2bb6a2..cebb4dd29640 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76.h
@@ -507,6 +507,7 @@ struct mt76_sdio {
void *intr_data;
int intr_size;
u8 hw_ver;
+ wait_queue_head_t wait;

struct {
int pse_data_quota;
@@ -1251,6 +1252,7 @@ int mt76s_alloc_queues(struct mt76_dev *dev);
void mt76s_deinit(struct mt76_dev *dev);
void mt76s_sdio_irq(struct sdio_func *func);
void mt76s_txrx_worker(struct mt76_sdio *sdio);
+bool mt76s_txqs_empty(struct mt76_dev *dev);
int mt76s_hw_init(struct mt76_dev *dev, struct sdio_func *func,
int hw_ver);
u32 mt76s_rr(struct mt76_dev *dev, u32 offset);
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/init.c b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
index 2b7260be224f..87265045e2dd 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/init.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/init.c
@@ -217,6 +217,8 @@ int mt7921_register_device(struct mt7921_dev *dev)
spin_lock_init(&dev->pm.wake.lock);
mutex_init(&dev->pm.mutex);
init_waitqueue_head(&dev->pm.wait);
+ if (mt76_is_sdio(&dev->mt76))
+ init_waitqueue_head(&dev->mt76.sdio.wait);
spin_lock_init(&dev->pm.txq_lock);
INIT_DELAYED_WORK(&dev->mphy.mac_work, mt7921_mac_work);
INIT_DELAYED_WORK(&dev->phy.scan_work, mt7921_scan_work);
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c
index 11f4df918fdb..1ae988a7de76 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/mcu.c
@@ -439,6 +439,7 @@ mt7921_mcu_rx_unsolicited_event(struct mt7921_dev *dev, struct sk_buff *skb)
mt7921_mcu_debug_msg_event(dev, skb);
break;
case MCU_EVENT_COREDUMP:
+ dev->fw_assert = true;
mt76_connac_mcu_coredump_event(&dev->mt76, skb,
&dev->coredump);
return;
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h b/drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h
index 6d0edb8ce1d6..c96d4e841e12 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/mt7921.h
@@ -169,6 +169,7 @@ struct mt7921_dev {
struct work_struct reset_work;
bool hw_full_reset:1;
bool hw_init_done:1;
+ bool fw_assert:1;

struct list_head sta_poll_list;
spinlock_t sta_poll_lock;
@@ -412,6 +413,9 @@ void mt7921e_queue_rx_skb(struct mt76_dev *mdev, enum mt76_rxq_id q,
struct sk_buff *skb);
int mt7921e_mac_reset(struct mt7921_dev *dev);
int mt7921e_mcu_init(struct mt7921_dev *dev);
+int mt7921s_wfsys_reset(struct mt7921_dev *dev);
+int mt7921s_mac_reset(struct mt7921_dev *dev);
+int mt7921s_init_reset(struct mt7921_dev *dev);
int mt7921e_mcu_drv_pmctrl(struct mt7921_dev *dev);
int mt7921e_mcu_fw_pmctrl(struct mt7921_dev *dev);

diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/sdio.c b/drivers/net/wireless/mediatek/mt76/mt7921/sdio.c
index 87d0954a7989..d6aa4c07cc99 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/sdio.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/sdio.c
@@ -46,6 +46,7 @@ static void mt7921s_unregister_device(struct mt7921_dev *dev)
cancel_work_sync(&pm->wake_work);

mt76s_deinit(&dev->mt76);
+ mt7921s_wfsys_reset(dev);
mt7921_mcu_exit(dev);

mt76_free_device(&dev->mt76);
@@ -80,6 +81,8 @@ static int mt7921s_probe(struct sdio_func *func,
.type = MT76_BUS_SDIO,
};
static const struct mt7921_hif_ops mt7921_sdio_ops = {
+ .init_reset = mt7921s_init_reset,
+ .reset = mt7921s_mac_reset,
.mcu_init = mt7921s_mcu_init,
.drv_own = mt7921s_mcu_drv_pmctrl,
.fw_own = mt7921s_mcu_fw_pmctrl,
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mac.c b/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mac.c
index 91a7acd49ee4..137f86a6dbf8 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mac.c
@@ -5,6 +5,139 @@
#include <linux/mmc/sdio_func.h>
#include "mt7921.h"
#include "mac.h"
+#include "../sdio.h"
+
+static void mt7921s_enable_irq(struct mt76_dev *dev)
+{
+ struct mt76_sdio *sdio = &dev->sdio;
+
+ sdio_claim_host(sdio->func);
+ sdio_writel(sdio->func, WHLPCR_INT_EN_SET, MCR_WHLPCR, NULL);
+ sdio_release_host(sdio->func);
+}
+
+static void mt7921s_disable_irq(struct mt76_dev *dev)
+{
+ struct mt76_sdio *sdio = &dev->sdio;
+
+ sdio_claim_host(sdio->func);
+ sdio_writel(sdio->func, WHLPCR_INT_EN_CLR, MCR_WHLPCR, NULL);
+ sdio_release_host(sdio->func);
+}
+
+static u32 mt7921s_read_whcr(struct mt76_dev *dev)
+{
+ return sdio_readl(dev->sdio.func, MCR_WHCR, NULL);
+}
+
+int mt7921s_wfsys_reset(struct mt7921_dev *dev)
+{
+ struct mt76_sdio *sdio = &dev->mt76.sdio;
+ u32 val, status;
+
+ mt7921s_mcu_drv_pmctrl(dev);
+
+ sdio_claim_host(sdio->func);
+
+ val = sdio_readl(sdio->func, MCR_WHCR, NULL);
+ val &= ~WF_WHOLE_PATH_RSTB;
+ sdio_writel(sdio->func, val, MCR_WHCR, NULL);
+
+ msleep(50);
+
+ val = sdio_readl(sdio->func, MCR_WHCR, NULL);
+ val &= ~WF_SDIO_WF_PATH_RSTB;
+ sdio_writel(sdio->func, val, MCR_WHCR, NULL);
+
+ usleep_range(1000, 2000);
+
+ val = sdio_readl(sdio->func, MCR_WHCR, NULL);
+ val |= WF_WHOLE_PATH_RSTB;
+ sdio_writel(sdio->func, val, MCR_WHCR, NULL);
+
+ readx_poll_timeout(mt7921s_read_whcr, &dev->mt76, status,
+ status & WF_RST_DONE, 50000, 2000000);
+
+ sdio_release_host(sdio->func);
+
+ /* activate mt7921s again */
+ mt7921s_mcu_fw_pmctrl(dev);
+ mt7921s_mcu_drv_pmctrl(dev);
+
+ return 0;
+}
+
+int mt7921s_init_reset(struct mt7921_dev *dev)
+{
+ set_bit(MT76_MCU_RESET, &dev->mphy.state);
+
+ wake_up(&dev->mt76.mcu.wait);
+ skb_queue_purge(&dev->mt76.mcu.res_q);
+ wait_event_timeout(dev->mt76.sdio.wait,
+ mt76s_txqs_empty(&dev->mt76), 5 * HZ);
+ mt76_worker_disable(&dev->mt76.sdio.txrx_worker);
+
+ mt7921s_disable_irq(&dev->mt76);
+ mt7921s_wfsys_reset(dev);
+
+ mt76_worker_enable(&dev->mt76.sdio.txrx_worker);
+ clear_bit(MT76_STATE_MCU_RUNNING, &dev->mphy.state);
+ clear_bit(MT76_MCU_RESET, &dev->mphy.state);
+ mt7921s_enable_irq(&dev->mt76);
+
+ return 0;
+}
+
+int mt7921s_mac_reset(struct mt7921_dev *dev)
+{
+ int err;
+
+ mt76_connac_free_pending_tx_skbs(&dev->pm, NULL);
+ mt76_txq_schedule_all(&dev->mphy);
+ mt76_worker_disable(&dev->mt76.tx_worker);
+ set_bit(MT76_RESET, &dev->mphy.state);
+ set_bit(MT76_MCU_RESET, &dev->mphy.state);
+ wake_up(&dev->mt76.mcu.wait);
+ skb_queue_purge(&dev->mt76.mcu.res_q);
+ wait_event_timeout(dev->mt76.sdio.wait,
+ mt76s_txqs_empty(&dev->mt76), 5 * HZ);
+ mt76_worker_disable(&dev->mt76.sdio.txrx_worker);
+ mt76_worker_disable(&dev->mt76.sdio.status_worker);
+ mt76_worker_disable(&dev->mt76.sdio.net_worker);
+ cancel_work_sync(&dev->mt76.sdio.stat_work);
+
+ mt7921s_disable_irq(&dev->mt76);
+ mt7921s_wfsys_reset(dev);
+
+ mt76_worker_enable(&dev->mt76.sdio.txrx_worker);
+ mt76_worker_enable(&dev->mt76.sdio.status_worker);
+ mt76_worker_enable(&dev->mt76.sdio.net_worker);
+
+ dev->fw_assert = false;
+ clear_bit(MT76_STATE_MCU_RUNNING, &dev->mphy.state);
+ clear_bit(MT76_MCU_RESET, &dev->mphy.state);
+ mt7921s_enable_irq(&dev->mt76);
+
+ err = mt7921_run_firmware(dev);
+ if (err)
+ goto out;
+
+ err = mt7921_mcu_set_eeprom(dev);
+ if (err)
+ goto out;
+
+ err = mt7921_mac_init(dev);
+ if (err)
+ goto out;
+
+ err = __mt7921_start(&dev->phy);
+out:
+ clear_bit(MT76_RESET, &dev->mphy.state);
+
+ mt76_worker_enable(&dev->mt76.tx_worker);
+
+ return err;
+}

static void
mt7921s_write_txwi(struct mt7921_dev *dev, struct mt76_wcid *wcid,
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mcu.c b/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mcu.c
index 049e06d7c3fb..437cddad9a90 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mcu.c
@@ -21,6 +21,14 @@ mt7921s_mcu_send_message(struct mt76_dev *mdev, struct sk_buff *skb,
enum mt76_mcuq_id txq = MT_MCUQ_WM;
int ret, pad;

+ /* We just return in case firmware assertion to avoid blocking the
+ * common workqueue to run, for example, the coredump work might be
+ * blocked by mt7921_mac_work that is excuting register access via sdio
+ * bus.
+ */
+ if (dev->fw_assert)
+ return -EBUSY;
+
ret = mt7921_mcu_fill_message(mdev, skb, cmd, seq);
if (ret)
return ret;
diff --git a/drivers/net/wireless/mediatek/mt76/sdio_txrx.c b/drivers/net/wireless/mediatek/mt76/sdio_txrx.c
index 8de84ec556a1..cdf1d7c15241 100644
--- a/drivers/net/wireless/mediatek/mt76/sdio_txrx.c
+++ b/drivers/net/wireless/mediatek/mt76/sdio_txrx.c
@@ -272,6 +272,9 @@ static int mt76s_tx_run_queue(struct mt76_dev *dev, struct mt76_queue *q)

smp_rmb();

+ if (test_bit(MT76_MCU_RESET, &dev->phy.state))
+ goto next;
+
if (!test_bit(MT76_STATE_MCU_RUNNING, &dev->phy.state)) {
__skb_put_zero(e->skb, 4);
err = __mt76s_xmit_queue(dev, e->skb->data,
@@ -350,6 +353,13 @@ void mt76s_txrx_worker(struct mt76_sdio *sdio)
ret = mt76s_rx_handler(dev);
if (ret > 0)
nframes += ret;
+
+ if (test_bit(MT76_MCU_RESET, &dev->phy.state)) {
+ if (!mt76s_txqs_empty(dev))
+ continue;
+ else
+ wake_up(&sdio->wait);
+ }
} while (nframes > 0);

/* enable interrupt */
@@ -363,9 +373,29 @@ void mt76s_sdio_irq(struct sdio_func *func)
struct mt76_dev *dev = sdio_get_drvdata(func);
struct mt76_sdio *sdio = &dev->sdio;

- if (!test_bit(MT76_STATE_INITIALIZED, &dev->phy.state))
+ if (!test_bit(MT76_STATE_INITIALIZED, &dev->phy.state) ||
+ test_bit(MT76_MCU_RESET, &dev->phy.state))
return;

mt76_worker_schedule(&sdio->txrx_worker);
}
EXPORT_SYMBOL_GPL(mt76s_sdio_irq);
+
+bool mt76s_txqs_empty(struct mt76_dev *dev)
+{
+ struct mt76_queue *q;
+ int i;
+
+ for (i = 0; i <= MT_TXQ_PSD + 1; i++) {
+ if (i <= MT_TXQ_PSD)
+ q = dev->phy.q_tx[i];
+ else
+ q = dev->q_mcu[MT_MCUQ_WM];
+
+ if (q->first != q->head)
+ return false;
+ }
+
+ return true;
+}
+EXPORT_SYMBOL_GPL(mt76s_txqs_empty);
--
2.25.1