Commit 893b838e authored by Alex Elder's avatar Alex Elder Committed by Jakub Kicinski
Browse files

net: ipa: introduce __gsi_channel_start() 



Create a new function that does most of the work of starting a
channel.  What's different is that it takes a flag indicating
whether the channel should really be started or not.  Create
another new function __gsi_channel_stop() that behaves similarly.

IPA v3.5.1 implements suspend using a special SUSPEND endpoint
setting.  If the endpoint is suspended when an I/O completes on the
underlying GSI channel, a SUSPEND interrupt is generated.

Newer versions of IPA do not implement the SUSPEND endpoint mode.
Instead, endpoint suspend is implemented by simply stopping the
underlying GSI channel.  In this case, a completing I/O on a
*stopped* channel causes the SUSPEND interrupt condition.

These new functions put all activity related to starting or stopping
a channel (including "thawing/freezing" the channel) in one place,
whether or not the channel is actually started or stopped.

Signed-off-by: default avatarAlex Elder <elder@linaro.org>
Acked-by: default avatarWillem de Bruijn <willemb@google.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 697e834e

drivers/net/ipa/gsi.c

+23 −20
Original line number Diff line number Diff line
@@ -873,15 +873,14 @@ static void gsi_channel_deprogram(struct gsi_channel *channel) 
	/* Nothing to do */

}



/* Start an allocated GSI channel */

int gsi_channel_start(struct gsi *gsi, u32 channel_id)

static int __gsi_channel_start(struct gsi_channel *channel, bool start)

{

	struct gsi_channel *channel = &gsi->channel[channel_id];

	struct gsi *gsi = channel->gsi;

	int ret;



	mutex_lock(&gsi->mutex);



	ret = gsi_channel_start_command(channel);

	ret = start ? gsi_channel_start_command(channel) : 0;



	mutex_unlock(&gsi->mutex);
@@ -892,6 +891,14 @@ int gsi_channel_start(struct gsi *gsi, u32 channel_id) 
	return ret;

}



/* Start an allocated GSI channel */

int gsi_channel_start(struct gsi *gsi, u32 channel_id)

{

	struct gsi_channel *channel = &gsi->channel[channel_id];



	return __gsi_channel_start(channel, true);

}



static int gsi_channel_stop_retry(struct gsi_channel *channel)

{

	u32 retries = GSI_CHANNEL_STOP_RETRIES;
@@ -912,15 +919,13 @@ static int gsi_channel_stop_retry(struct gsi_channel *channel) 
	return ret;

}



/* Stop a started channel */

int gsi_channel_stop(struct gsi *gsi, u32 channel_id)

static int __gsi_channel_stop(struct gsi_channel *channel, bool stop)

{

	struct gsi_channel *channel = &gsi->channel[channel_id];

	int ret;



	gsi_channel_freeze(channel);



	ret = gsi_channel_stop_retry(channel);

	ret = stop ? gsi_channel_stop_retry(channel) : 0;



	/* Re-thaw the channel if an error occurred while stopping */

	if (ret)
@@ -929,6 +934,14 @@ int gsi_channel_stop(struct gsi *gsi, u32 channel_id) 
	return ret;

}



/* Stop a started channel */

int gsi_channel_stop(struct gsi *gsi, u32 channel_id)

{

	struct gsi_channel *channel = &gsi->channel[channel_id];



	return __gsi_channel_stop(channel, true);

}



/* Reset and reconfigure a channel, (possibly) enabling the doorbell engine */

void gsi_channel_reset(struct gsi *gsi, u32 channel_id, bool doorbell)

{
@@ -952,12 +965,7 @@ int gsi_channel_suspend(struct gsi *gsi, u32 channel_id, bool stop) 
{

	struct gsi_channel *channel = &gsi->channel[channel_id];



	if (stop)

		return gsi_channel_stop(gsi, channel_id);



	gsi_channel_freeze(channel);



	return 0;

	return __gsi_channel_stop(channel, stop);

}



/* Resume a suspended channel (starting will be requested if STOPPED) */
@@ -965,12 +973,7 @@ int gsi_channel_resume(struct gsi *gsi, u32 channel_id, bool start) 
{

	struct gsi_channel *channel = &gsi->channel[channel_id];



	if (start)

		return gsi_channel_start(gsi, channel_id);



	gsi_channel_thaw(channel);



	return 0;

	return __gsi_channel_start(channel, start);

}



/**