From: Mikko Perttunen mperttunen@nvidia.com
This is largely a rewrite of the Host1x channel allocation code, bringing several changes:
- The previous code could deadlock due to an interaction between the 'reflock' mutex and CDMA timeout handling. This gets rid of the mutex. - Support for more than 32 channels, required for Tegra186 - General refactoring, including better encapsulation of channel ownership handling into channel.c
Signed-off-by: Mikko Perttunen mperttunen@nvidia.com Reviewed-by: Dmitry Osipenko digetx@gmail.com Tested-by: Dmitry Osipenko digetx@gmail.com --- drivers/gpu/drm/tegra/gr2d.c | 4 +- drivers/gpu/drm/tegra/gr3d.c | 4 +- drivers/gpu/drm/tegra/vic.c | 4 +- drivers/gpu/host1x/channel.c | 147 +++++++++++++++++++++++-------------- drivers/gpu/host1x/channel.h | 21 ++++-- drivers/gpu/host1x/debug.c | 47 +++++------- drivers/gpu/host1x/dev.c | 7 +- drivers/gpu/host1x/dev.h | 6 +- drivers/gpu/host1x/hw/channel_hw.c | 4 - include/linux/host1x.h | 1 - 10 files changed, 135 insertions(+), 110 deletions(-)
diff --git a/drivers/gpu/drm/tegra/gr2d.c b/drivers/gpu/drm/tegra/gr2d.c index 782231c41a1a..693fd2b3aef6 100644 --- a/drivers/gpu/drm/tegra/gr2d.c +++ b/drivers/gpu/drm/tegra/gr2d.c @@ -38,7 +38,7 @@ static int gr2d_init(struct host1x_client *client)
client->syncpts[0] = host1x_syncpt_request(client->dev, flags); if (!client->syncpts[0]) { - host1x_channel_free(gr2d->channel); + host1x_channel_put(gr2d->channel); return -ENOMEM; }
@@ -57,7 +57,7 @@ static int gr2d_exit(struct host1x_client *client) return err;
host1x_syncpt_free(client->syncpts[0]); - host1x_channel_free(gr2d->channel); + host1x_channel_put(gr2d->channel);
return 0; } diff --git a/drivers/gpu/drm/tegra/gr3d.c b/drivers/gpu/drm/tegra/gr3d.c index 13f0d1b7cd98..cee2ab645cde 100644 --- a/drivers/gpu/drm/tegra/gr3d.c +++ b/drivers/gpu/drm/tegra/gr3d.c @@ -48,7 +48,7 @@ static int gr3d_init(struct host1x_client *client)
client->syncpts[0] = host1x_syncpt_request(client->dev, flags); if (!client->syncpts[0]) { - host1x_channel_free(gr3d->channel); + host1x_channel_put(gr3d->channel); return -ENOMEM; }
@@ -67,7 +67,7 @@ static int gr3d_exit(struct host1x_client *client) return err;
host1x_syncpt_free(client->syncpts[0]); - host1x_channel_free(gr3d->channel); + host1x_channel_put(gr3d->channel);
return 0; } diff --git a/drivers/gpu/drm/tegra/vic.c b/drivers/gpu/drm/tegra/vic.c index cd804e404a11..47cb1aaa58b1 100644 --- a/drivers/gpu/drm/tegra/vic.c +++ b/drivers/gpu/drm/tegra/vic.c @@ -182,7 +182,7 @@ static int vic_init(struct host1x_client *client) free_syncpt: host1x_syncpt_free(client->syncpts[0]); free_channel: - host1x_channel_free(vic->channel); + host1x_channel_put(vic->channel); detach_device: if (tegra->domain) iommu_detach_device(tegra->domain, vic->dev); @@ -203,7 +203,7 @@ static int vic_exit(struct host1x_client *client) return err;
host1x_syncpt_free(client->syncpts[0]); - host1x_channel_free(vic->channel); + host1x_channel_put(vic->channel);
if (vic->domain) { iommu_detach_device(vic->domain, vic->dev); 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); diff --git a/drivers/gpu/host1x/channel.h b/drivers/gpu/host1x/channel.h index df767cf90d51..7068e42d42df 100644 --- a/drivers/gpu/host1x/channel.h +++ b/drivers/gpu/host1x/channel.h @@ -20,17 +20,21 @@ #define __HOST1X_CHANNEL_H
#include <linux/io.h> +#include <linux/kref.h>
#include "cdma.h"
struct host1x; +struct host1x_channel;
-struct host1x_channel { - struct list_head list; +struct host1x_channel_list { + struct host1x_channel *channels; + unsigned long *allocated_channels; +};
- unsigned int refcount; +struct host1x_channel { + struct kref refcount; unsigned int id; - struct mutex reflock; struct mutex submitlock; void __iomem *regs; struct device *dev; @@ -38,9 +42,10 @@ struct host1x_channel { };
/* channel list operations */ -int host1x_channel_list_init(struct host1x *host); - -#define host1x_for_each_channel(host, channel) \ - list_for_each_entry(channel, &host->chlist.list, list) +int host1x_channel_list_init(struct host1x_channel_list *chlist, + unsigned int num_channels); +void host1x_channel_list_free(struct host1x_channel_list *chlist); +struct host1x_channel *host1x_channel_get_index(struct host1x *host, + unsigned int index);
#endif diff --git a/drivers/gpu/host1x/debug.c b/drivers/gpu/host1x/debug.c index d9330fcc62ad..2aae0e63214c 100644 --- a/drivers/gpu/host1x/debug.c +++ b/drivers/gpu/host1x/debug.c @@ -43,24 +43,19 @@ void host1x_debug_output(struct output *o, const char *fmt, ...) o->fn(o->ctx, o->buf, len); }
-static int show_channels(struct host1x_channel *ch, void *data, bool show_fifo) +static int show_channel(struct host1x_channel *ch, void *data, bool show_fifo) { struct host1x *m = dev_get_drvdata(ch->dev->parent); struct output *o = data;
- mutex_lock(&ch->reflock); + mutex_lock(&ch->cdma.lock);
- if (ch->refcount) { - mutex_lock(&ch->cdma.lock); + if (show_fifo) + host1x_hw_show_channel_fifo(m, ch, o);
- if (show_fifo) - host1x_hw_show_channel_fifo(m, ch, o); + host1x_hw_show_channel_cdma(m, ch, o);
- host1x_hw_show_channel_cdma(m, ch, o); - mutex_unlock(&ch->cdma.lock); - } - - mutex_unlock(&ch->reflock); + mutex_unlock(&ch->cdma.lock);
return 0; } @@ -94,28 +89,22 @@ static void show_syncpts(struct host1x *m, struct output *o) host1x_debug_output(o, "\n"); }
-static void show_all(struct host1x *m, struct output *o) +static void show_all(struct host1x *m, struct output *o, bool show_fifo) { - struct host1x_channel *ch; + int i;
host1x_hw_show_mlocks(m, o); show_syncpts(m, o); host1x_debug_output(o, "---- channels ----\n");
- host1x_for_each_channel(m, ch) - show_channels(ch, o, true); -} - -static void show_all_no_fifo(struct host1x *host1x, struct output *o) -{ - struct host1x_channel *ch; - - host1x_hw_show_mlocks(host1x, o); - show_syncpts(host1x, o); - host1x_debug_output(o, "---- channels ----\n"); + for (i = 0; i < m->info->nb_channels; ++i) { + struct host1x_channel *ch = host1x_channel_get_index(m, i);
- host1x_for_each_channel(host1x, ch) - show_channels(ch, o, false); + if (ch) { + show_channel(ch, o, show_fifo); + host1x_channel_put(ch); + } + } }
static int host1x_debug_show_all(struct seq_file *s, void *unused) @@ -125,7 +114,7 @@ static int host1x_debug_show_all(struct seq_file *s, void *unused) .ctx = s };
- show_all(s->private, &o); + show_all(s->private, &o, true);
return 0; } @@ -137,7 +126,7 @@ static int host1x_debug_show(struct seq_file *s, void *unused) .ctx = s };
- show_all_no_fifo(s->private, &o); + show_all(s->private, &o, false);
return 0; } @@ -216,7 +205,7 @@ void host1x_debug_dump(struct host1x *host1x) .fn = write_to_printk };
- show_all(host1x, &o); + show_all(host1x, &o, true); }
void host1x_debug_dump_syncpts(struct host1x *host1x) diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c index f05ebb14fa63..5c1c711a21af 100644 --- a/drivers/gpu/host1x/dev.c +++ b/drivers/gpu/host1x/dev.c @@ -198,7 +198,8 @@ static int host1x_probe(struct platform_device *pdev) host->iova_end = geometry->aperture_end; }
- err = host1x_channel_list_init(host); + err = host1x_channel_list_init(&host->channel_list, + host->info->nb_channels); if (err) { dev_err(&pdev->dev, "failed to initialize channel list\n"); goto fail_detach_device; @@ -207,7 +208,7 @@ static int host1x_probe(struct platform_device *pdev) err = clk_prepare_enable(host->clk); if (err < 0) { dev_err(&pdev->dev, "failed to enable clock\n"); - goto fail_detach_device; + goto fail_free_channels; }
err = reset_control_deassert(host->rst); @@ -244,6 +245,8 @@ static int host1x_probe(struct platform_device *pdev) reset_control_assert(host->rst); fail_unprepare_disable: clk_disable_unprepare(host->clk); +fail_free_channels: + host1x_channel_list_free(&host->channel_list); fail_detach_device: if (host->domain) { put_iova_domain(&host->iova); diff --git a/drivers/gpu/host1x/dev.h b/drivers/gpu/host1x/dev.h index 229d08b6a45e..ffdbc15b749b 100644 --- a/drivers/gpu/host1x/dev.h +++ b/drivers/gpu/host1x/dev.h @@ -129,10 +129,8 @@ struct host1x { struct host1x_syncpt *nop_sp;
struct mutex syncpt_mutex; - struct mutex chlist_mutex; - struct host1x_channel chlist; - unsigned long allocated_channels; - unsigned int num_allocated_channels; + + struct host1x_channel_list channel_list;
struct dentry *debugfs;
diff --git a/drivers/gpu/host1x/hw/channel_hw.c b/drivers/gpu/host1x/hw/channel_hw.c index 5e8df78b7acd..8447a56c41ca 100644 --- a/drivers/gpu/host1x/hw/channel_hw.c +++ b/drivers/gpu/host1x/hw/channel_hw.c @@ -181,10 +181,6 @@ static int channel_submit(struct host1x_job *job) static int host1x_channel_init(struct host1x_channel *ch, struct host1x *dev, unsigned int index) { - ch->id = index; - mutex_init(&ch->reflock); - mutex_init(&ch->submitlock); - ch->regs = dev->regs + index * HOST1X_CHANNEL_SIZE; return 0; } diff --git a/include/linux/host1x.h b/include/linux/host1x.h index 561d6bb6580d..5dd8df2f8810 100644 --- a/include/linux/host1x.h +++ b/include/linux/host1x.h @@ -156,7 +156,6 @@ struct host1x_channel; struct host1x_job;
struct host1x_channel *host1x_channel_request(struct device *dev); -void host1x_channel_free(struct host1x_channel *channel); struct host1x_channel *host1x_channel_get(struct host1x_channel *channel); void host1x_channel_put(struct host1x_channel *channel); int host1x_job_submit(struct host1x_job *job);