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path: root/drivers/gpu/host1x/channel.c
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Diffstat (limited to 'drivers/gpu/host1x/channel.c')
-rw-r--r--drivers/gpu/host1x/channel.c147
1 files changed, 91 insertions, 56 deletions
diff --git a/drivers/gpu/host1x/channel.c b/drivers/gpu/host1x/channel.c
index 8f437d924c10..db9b91d1384c 100644
--- a/drivers/gpu/host1x/channel.c
+++ b/drivers/gpu/host1x/channel.c
@@ -24,19 +24,33 @@
#include "job.h"
/* Constructor for the host1x device list */
-int host1x_channel_list_init(struct host1x *host)
+int host1x_channel_list_init(struct host1x_channel_list *chlist,
+ unsigned int num_channels)
{
- INIT_LIST_HEAD(&host->chlist.list);
- mutex_init(&host->chlist_mutex);
-
- if (host->info->nb_channels > BITS_PER_LONG) {
- WARN(1, "host1x hardware has more channels than supported by the driver\n");
- return -ENOSYS;
+ chlist->channels = kcalloc(num_channels, sizeof(struct host1x_channel),
+ GFP_KERNEL);
+ if (!chlist->channels)
+ return -ENOMEM;
+
+ chlist->allocated_channels =
+ kcalloc(BITS_TO_LONGS(num_channels), sizeof(unsigned long),
+ GFP_KERNEL);
+ if (!chlist->allocated_channels) {
+ kfree(chlist->channels);
+ return -ENOMEM;
}
+ bitmap_zero(chlist->allocated_channels, num_channels);
+
return 0;
}
+void host1x_channel_list_free(struct host1x_channel_list *chlist)
+{
+ kfree(chlist->allocated_channels);
+ kfree(chlist->channels);
+}
+
int host1x_job_submit(struct host1x_job *job)
{
struct host1x *host = dev_get_drvdata(job->channel->dev->parent);
@@ -47,86 +61,107 @@ EXPORT_SYMBOL(host1x_job_submit);
struct host1x_channel *host1x_channel_get(struct host1x_channel *channel)
{
- int err = 0;
+ kref_get(&channel->refcount);
- mutex_lock(&channel->reflock);
+ return channel;
+}
+EXPORT_SYMBOL(host1x_channel_get);
- if (channel->refcount == 0)
- err = host1x_cdma_init(&channel->cdma);
+/**
+ * host1x_channel_get_index() - Attempt to get channel reference by index
+ * @host: Host1x device object
+ * @index: Index of channel
+ *
+ * If channel number @index is currently allocated, increase its refcount
+ * and return a pointer to it. Otherwise, return NULL.
+ */
+struct host1x_channel *host1x_channel_get_index(struct host1x *host,
+ unsigned int index)
+{
+ struct host1x_channel *ch = &host->channel_list.channels[index];
- if (!err)
- channel->refcount++;
+ if (!kref_get_unless_zero(&ch->refcount))
+ return NULL;
- mutex_unlock(&channel->reflock);
+ return ch;
+}
+
+static void release_channel(struct kref *kref)
+{
+ struct host1x_channel *channel =
+ container_of(kref, struct host1x_channel, refcount);
+ struct host1x *host = dev_get_drvdata(channel->dev->parent);
+ struct host1x_channel_list *chlist = &host->channel_list;
+
+ host1x_hw_cdma_stop(host, &channel->cdma);
+ host1x_cdma_deinit(&channel->cdma);
- return err ? NULL : channel;
+ clear_bit(channel->id, chlist->allocated_channels);
}
-EXPORT_SYMBOL(host1x_channel_get);
void host1x_channel_put(struct host1x_channel *channel)
{
- mutex_lock(&channel->reflock);
+ kref_put(&channel->refcount, release_channel);
+}
+EXPORT_SYMBOL(host1x_channel_put);
- if (channel->refcount == 1) {
- struct host1x *host = dev_get_drvdata(channel->dev->parent);
+static struct host1x_channel *acquire_unused_channel(struct host1x *host)
+{
+ struct host1x_channel_list *chlist = &host->channel_list;
+ unsigned int max_channels = host->info->nb_channels;
+ unsigned int index;
- host1x_hw_cdma_stop(host, &channel->cdma);
- host1x_cdma_deinit(&channel->cdma);
+ index = find_first_zero_bit(chlist->allocated_channels, max_channels);
+ if (index >= max_channels) {
+ dev_err(host->dev, "failed to find free channel\n");
+ return NULL;
}
- channel->refcount--;
+ chlist->channels[index].id = index;
- mutex_unlock(&channel->reflock);
+ set_bit(index, chlist->allocated_channels);
+
+ return &chlist->channels[index];
}
-EXPORT_SYMBOL(host1x_channel_put);
+/**
+ * host1x_channel_request() - Allocate a channel
+ * @device: Host1x unit this channel will be used to send commands to
+ *
+ * Allocates a new host1x channel for @device. If there are no free channels,
+ * this will sleep until one becomes available. May return NULL if CDMA
+ * initialization fails.
+ */
struct host1x_channel *host1x_channel_request(struct device *dev)
{
struct host1x *host = dev_get_drvdata(dev->parent);
- unsigned int max_channels = host->info->nb_channels;
- struct host1x_channel *channel = NULL;
- unsigned long index;
+ struct host1x_channel_list *chlist = &host->channel_list;
+ struct host1x_channel *channel;
int err;
- mutex_lock(&host->chlist_mutex);
+ channel = acquire_unused_channel(host);
+ if (!channel)
+ return NULL;
- index = find_first_zero_bit(&host->allocated_channels, max_channels);
- if (index >= max_channels)
- goto fail;
+ kref_init(&channel->refcount);
+ mutex_init(&channel->submitlock);
+ channel->dev = dev;
- channel = kzalloc(sizeof(*channel), GFP_KERNEL);
- if (!channel)
+ err = host1x_hw_channel_init(host, channel, channel->id);
+ if (err < 0)
goto fail;
- err = host1x_hw_channel_init(host, channel, index);
+ err = host1x_cdma_init(&channel->cdma);
if (err < 0)
goto fail;
- /* Link device to host1x_channel */
- channel->dev = dev;
-
- /* Add to channel list */
- list_add_tail(&channel->list, &host->chlist.list);
-
- host->allocated_channels |= BIT(index);
-
- mutex_unlock(&host->chlist_mutex);
return channel;
fail:
- dev_err(dev, "failed to init channel\n");
- kfree(channel);
- mutex_unlock(&host->chlist_mutex);
- return NULL;
-}
-EXPORT_SYMBOL(host1x_channel_request);
+ clear_bit(channel->id, chlist->allocated_channels);
-void host1x_channel_free(struct host1x_channel *channel)
-{
- struct host1x *host = dev_get_drvdata(channel->dev->parent);
+ dev_err(dev, "failed to initialize channel\n");
- host->allocated_channels &= ~BIT(channel->id);
- list_del(&channel->list);
- kfree(channel);
+ return NULL;
}
-EXPORT_SYMBOL(host1x_channel_free);
+EXPORT_SYMBOL(host1x_channel_request);