[PATCH v6 20/30] soc: fsl: cpm1: qmc: Handle timeslot entries at channel start() and stop()

From: Herve Codina
Date: Fri Sep 22 2023 - 04:02:43 EST


In order to support runtime timeslot route changes, enable the
channel timeslot entries at channel start() and disable them at
channel stop().

Signed-off-by: Herve Codina <herve.codina@xxxxxxxxxxx>
Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
drivers/soc/fsl/qe/qmc.c | 175 ++++++++++++++++++++++++++++++++++++---
1 file changed, 163 insertions(+), 12 deletions(-)

diff --git a/drivers/soc/fsl/qe/qmc.c b/drivers/soc/fsl/qe/qmc.c
index 19acfcded9bc..185e6e87a83f 100644
--- a/drivers/soc/fsl/qe/qmc.c
+++ b/drivers/soc/fsl/qe/qmc.c
@@ -177,6 +177,7 @@ struct qmc_chan {
struct qmc *qmc;
void __iomem *s_param;
enum qmc_mode mode;
+ spinlock_t ts_lock; /* Protect timeslots */
u64 tx_ts_mask_avail;
u64 tx_ts_mask;
u64 rx_ts_mask_avail;
@@ -265,6 +266,7 @@ static void qmc_setbits32(void __iomem *addr, u32 set)
int qmc_chan_get_info(struct qmc_chan *chan, struct qmc_chan_info *info)
{
struct tsa_serial_info tsa_info;
+ unsigned long flags;
int ret;

/* Retrieve info from the TSA related serial */
@@ -272,6 +274,8 @@ int qmc_chan_get_info(struct qmc_chan *chan, struct qmc_chan_info *info)
if (ret)
return ret;

+ spin_lock_irqsave(&chan->ts_lock, flags);
+
info->mode = chan->mode;
info->rx_fs_rate = tsa_info.rx_fs_rate;
info->rx_bit_rate = tsa_info.rx_bit_rate;
@@ -280,6 +284,8 @@ int qmc_chan_get_info(struct qmc_chan *chan, struct qmc_chan_info *info)
info->tx_bit_rate = tsa_info.tx_bit_rate;
info->nb_rx_ts = hweight64(chan->rx_ts_mask);

+ spin_unlock_irqrestore(&chan->ts_lock, flags);
+
return 0;
}
EXPORT_SYMBOL(qmc_chan_get_info);
@@ -683,6 +689,40 @@ static int qmc_chan_setup_tsa_32tx(struct qmc_chan *chan, const struct tsa_seria
return 0;
}

+static int qmc_chan_setup_tsa_tx(struct qmc_chan *chan, bool enable)
+{
+ struct tsa_serial_info info;
+ int ret;
+
+ /* Retrieve info from the TSA related serial */
+ ret = tsa_serial_get_info(chan->qmc->tsa_serial, &info);
+ if (ret)
+ return ret;
+
+ /* Setup entries */
+ if (chan->qmc->is_tsa_64rxtx)
+ return qmc_chan_setup_tsa_64rxtx(chan, &info, enable);
+
+ return qmc_chan_setup_tsa_32tx(chan, &info, enable);
+}
+
+static int qmc_chan_setup_tsa_rx(struct qmc_chan *chan, bool enable)
+{
+ struct tsa_serial_info info;
+ int ret;
+
+ /* Retrieve info from the TSA related serial */
+ ret = tsa_serial_get_info(chan->qmc->tsa_serial, &info);
+ if (ret)
+ return ret;
+
+ /* Setup entries */
+ if (chan->qmc->is_tsa_64rxtx)
+ return qmc_chan_setup_tsa_64rxtx(chan, &info, enable);
+
+ return qmc_chan_setup_tsa_32rx(chan, &info, enable);
+}
+
static int qmc_chan_setup_tsa(struct qmc_chan *chan, bool enable)
{
struct tsa_serial_info info;
@@ -719,6 +759,12 @@ static int qmc_chan_stop_rx(struct qmc_chan *chan)

spin_lock_irqsave(&chan->rx_lock, flags);

+ if (chan->is_rx_stopped) {
+ /* The channel is already stopped -> simply return ok */
+ ret = 0;
+ goto end;
+ }
+
/* Send STOP RECEIVE command */
ret = qmc_chan_command(chan, 0x0);
if (ret) {
@@ -729,6 +775,15 @@ static int qmc_chan_stop_rx(struct qmc_chan *chan)

chan->is_rx_stopped = true;

+ if (!chan->qmc->is_tsa_64rxtx || chan->is_tx_stopped) {
+ ret = qmc_chan_setup_tsa_rx(chan, false);
+ if (ret) {
+ dev_err(chan->qmc->dev, "chan %u: Disable tsa entries failed (%d)\n",
+ chan->id, ret);
+ goto end;
+ }
+ }
+
end:
spin_unlock_irqrestore(&chan->rx_lock, flags);
return ret;
@@ -741,6 +796,12 @@ static int qmc_chan_stop_tx(struct qmc_chan *chan)

spin_lock_irqsave(&chan->tx_lock, flags);

+ if (chan->is_tx_stopped) {
+ /* The channel is already stopped -> simply return ok */
+ ret = 0;
+ goto end;
+ }
+
/* Send STOP TRANSMIT command */
ret = qmc_chan_command(chan, 0x1);
if (ret) {
@@ -751,37 +812,82 @@ static int qmc_chan_stop_tx(struct qmc_chan *chan)

chan->is_tx_stopped = true;

+ if (!chan->qmc->is_tsa_64rxtx || chan->is_rx_stopped) {
+ ret = qmc_chan_setup_tsa_tx(chan, false);
+ if (ret) {
+ dev_err(chan->qmc->dev, "chan %u: Disable tsa entries failed (%d)\n",
+ chan->id, ret);
+ goto end;
+ }
+ }
+
end:
spin_unlock_irqrestore(&chan->tx_lock, flags);
return ret;
}

+static int qmc_chan_start_rx(struct qmc_chan *chan);
+
int qmc_chan_stop(struct qmc_chan *chan, int direction)
{
- int ret;
+ bool is_rx_rollback_needed = false;
+ unsigned long flags;
+ int ret = 0;
+
+ spin_lock_irqsave(&chan->ts_lock, flags);

if (direction & QMC_CHAN_READ) {
+ is_rx_rollback_needed = !chan->is_rx_stopped;
ret = qmc_chan_stop_rx(chan);
if (ret)
- return ret;
+ goto end;
}

if (direction & QMC_CHAN_WRITE) {
ret = qmc_chan_stop_tx(chan);
- if (ret)
- return ret;
+ if (ret) {
+ /* Restart rx if needed */
+ if (is_rx_rollback_needed)
+ qmc_chan_start_rx(chan);
+ goto end;
+ }
}

- return 0;
+end:
+ spin_unlock_irqrestore(&chan->ts_lock, flags);
+ return ret;
}
EXPORT_SYMBOL(qmc_chan_stop);

-static void qmc_chan_start_rx(struct qmc_chan *chan)
+static int qmc_setup_chan_trnsync(struct qmc *qmc, struct qmc_chan *chan);
+
+static int qmc_chan_start_rx(struct qmc_chan *chan)
{
unsigned long flags;
+ int ret;

spin_lock_irqsave(&chan->rx_lock, flags);

+ if (!chan->is_rx_stopped) {
+ /* The channel is already started -> simply return ok */
+ ret = 0;
+ goto end;
+ }
+
+ ret = qmc_chan_setup_tsa_rx(chan, true);
+ if (ret) {
+ dev_err(chan->qmc->dev, "chan %u: Enable tsa entries failed (%d)\n",
+ chan->id, ret);
+ goto end;
+ }
+
+ ret = qmc_setup_chan_trnsync(chan->qmc, chan);
+ if (ret) {
+ dev_err(chan->qmc->dev, "chan %u: setup TRNSYNC failed (%d)\n",
+ chan->id, ret);
+ goto end;
+ }
+
/* Restart the receiver */
if (chan->mode == QMC_TRANSPARENT)
qmc_write32(chan->s_param + QMC_SPE_ZDSTATE, 0x18000080);
@@ -792,15 +898,38 @@ static void qmc_chan_start_rx(struct qmc_chan *chan)

chan->is_rx_stopped = false;

+end:
spin_unlock_irqrestore(&chan->rx_lock, flags);
+ return ret;
}

-static void qmc_chan_start_tx(struct qmc_chan *chan)
+static int qmc_chan_start_tx(struct qmc_chan *chan)
{
unsigned long flags;
+ int ret;

spin_lock_irqsave(&chan->tx_lock, flags);

+ if (!chan->is_tx_stopped) {
+ /* The channel is already started -> simply return ok */
+ ret = 0;
+ goto end;
+ }
+
+ ret = qmc_chan_setup_tsa_tx(chan, true);
+ if (ret) {
+ dev_err(chan->qmc->dev, "chan %u: Enable tsa entries failed (%d)\n",
+ chan->id, ret);
+ goto end;
+ }
+
+ ret = qmc_setup_chan_trnsync(chan->qmc, chan);
+ if (ret) {
+ dev_err(chan->qmc->dev, "chan %u: setup TRNSYNC failed (%d)\n",
+ chan->id, ret);
+ goto end;
+ }
+
/*
* Enable channel transmitter as it could be disabled if
* qmc_chan_reset() was called.
@@ -812,18 +941,39 @@ static void qmc_chan_start_tx(struct qmc_chan *chan)

chan->is_tx_stopped = false;

+end:
spin_unlock_irqrestore(&chan->tx_lock, flags);
+ return ret;
}

int qmc_chan_start(struct qmc_chan *chan, int direction)
{
- if (direction & QMC_CHAN_READ)
- qmc_chan_start_rx(chan);
+ bool is_rx_rollback_needed = false;
+ unsigned long flags;
+ int ret = 0;

- if (direction & QMC_CHAN_WRITE)
- qmc_chan_start_tx(chan);
+ spin_lock_irqsave(&chan->ts_lock, flags);

- return 0;
+ if (direction & QMC_CHAN_READ) {
+ is_rx_rollback_needed = chan->is_rx_stopped;
+ ret = qmc_chan_start_rx(chan);
+ if (ret)
+ goto end;
+ }
+
+ if (direction & QMC_CHAN_WRITE) {
+ ret = qmc_chan_start_tx(chan);
+ if (ret) {
+ /* Restop rx if needed */
+ if (is_rx_rollback_needed)
+ qmc_chan_stop_rx(chan);
+ goto end;
+ }
+ }
+
+end:
+ spin_unlock_irqrestore(&chan->ts_lock, flags);
+ return ret;
}
EXPORT_SYMBOL(qmc_chan_start);

@@ -992,6 +1142,7 @@ static int qmc_of_parse_chans(struct qmc *qmc, struct device_node *np)
}

chan->id = chan_id;
+ spin_lock_init(&chan->ts_lock);
spin_lock_init(&chan->rx_lock);
spin_lock_init(&chan->tx_lock);

--
2.41.0