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authorTerje Bergstrom <tbergstrom@nvidia.com>2013-03-22 16:34:03 +0200
committerThierry Reding <thierry.reding@avionic-design.de>2013-04-22 12:32:43 +0200
commit6579324a41cc414009a601738b70a53d6376325c (patch)
tree61b3491351217d07ff75851c6d989bf02b213383 /drivers/gpu/host1x/cdma.c
parent7ede0b0bf3e2595d40d6195b6fe4c4dcef438830 (diff)
gpu: host1x: Add channel support
Add support for host1x client modules, and host1x channels to submit work to the clients. Signed-off-by: Arto Merilainen <amerilainen@nvidia.com> Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com> Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de> Tested-by: Thierry Reding <thierry.reding@avionic-design.de> Tested-by: Erik Faye-Lund <kusmabite@gmail.com> Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Diffstat (limited to 'drivers/gpu/host1x/cdma.c')
-rw-r--r--drivers/gpu/host1x/cdma.c487
1 files changed, 487 insertions, 0 deletions
diff --git a/drivers/gpu/host1x/cdma.c b/drivers/gpu/host1x/cdma.c
new file mode 100644
index 000000000000..33935de91bb1
--- /dev/null
+++ b/drivers/gpu/host1x/cdma.c
@@ -0,0 +1,487 @@
+/*
+ * Tegra host1x Command DMA
+ *
+ * Copyright (c) 2010-2013, NVIDIA Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include <asm/cacheflush.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/kfifo.h>
+#include <linux/slab.h>
+#include <trace/events/host1x.h>
+
+#include "cdma.h"
+#include "channel.h"
+#include "dev.h"
+#include "debug.h"
+#include "host1x_bo.h"
+#include "job.h"
+
+/*
+ * push_buffer
+ *
+ * The push buffer is a circular array of words to be fetched by command DMA.
+ * Note that it works slightly differently to the sync queue; fence == pos
+ * means that the push buffer is full, not empty.
+ */
+
+#define HOST1X_PUSHBUFFER_SLOTS 512
+
+/*
+ * Clean up push buffer resources
+ */
+static void host1x_pushbuffer_destroy(struct push_buffer *pb)
+{
+ struct host1x_cdma *cdma = pb_to_cdma(pb);
+ struct host1x *host1x = cdma_to_host1x(cdma);
+
+ if (pb->phys != 0)
+ dma_free_writecombine(host1x->dev, pb->size_bytes + 4,
+ pb->mapped, pb->phys);
+
+ pb->mapped = NULL;
+ pb->phys = 0;
+}
+
+/*
+ * Init push buffer resources
+ */
+static int host1x_pushbuffer_init(struct push_buffer *pb)
+{
+ struct host1x_cdma *cdma = pb_to_cdma(pb);
+ struct host1x *host1x = cdma_to_host1x(cdma);
+
+ pb->mapped = NULL;
+ pb->phys = 0;
+ pb->size_bytes = HOST1X_PUSHBUFFER_SLOTS * 8;
+
+ /* initialize buffer pointers */
+ pb->fence = pb->size_bytes - 8;
+ pb->pos = 0;
+
+ /* allocate and map pushbuffer memory */
+ pb->mapped = dma_alloc_writecombine(host1x->dev, pb->size_bytes + 4,
+ &pb->phys, GFP_KERNEL);
+ if (!pb->mapped)
+ goto fail;
+
+ host1x_hw_pushbuffer_init(host1x, pb);
+
+ return 0;
+
+fail:
+ host1x_pushbuffer_destroy(pb);
+ return -ENOMEM;
+}
+
+/*
+ * Push two words to the push buffer
+ * Caller must ensure push buffer is not full
+ */
+static void host1x_pushbuffer_push(struct push_buffer *pb, u32 op1, u32 op2)
+{
+ u32 pos = pb->pos;
+ u32 *p = (u32 *)((u32)pb->mapped + pos);
+ WARN_ON(pos == pb->fence);
+ *(p++) = op1;
+ *(p++) = op2;
+ pb->pos = (pos + 8) & (pb->size_bytes - 1);
+}
+
+/*
+ * Pop a number of two word slots from the push buffer
+ * Caller must ensure push buffer is not empty
+ */
+static void host1x_pushbuffer_pop(struct push_buffer *pb, unsigned int slots)
+{
+ /* Advance the next write position */
+ pb->fence = (pb->fence + slots * 8) & (pb->size_bytes - 1);
+}
+
+/*
+ * Return the number of two word slots free in the push buffer
+ */
+static u32 host1x_pushbuffer_space(struct push_buffer *pb)
+{
+ return ((pb->fence - pb->pos) & (pb->size_bytes - 1)) / 8;
+}
+
+/*
+ * Sleep (if necessary) until the requested event happens
+ * - CDMA_EVENT_SYNC_QUEUE_EMPTY : sync queue is completely empty.
+ * - Returns 1
+ * - CDMA_EVENT_PUSH_BUFFER_SPACE : there is space in the push buffer
+ * - Return the amount of space (> 0)
+ * Must be called with the cdma lock held.
+ */
+unsigned int host1x_cdma_wait_locked(struct host1x_cdma *cdma,
+ enum cdma_event event)
+{
+ for (;;) {
+ unsigned int space;
+
+ if (event == CDMA_EVENT_SYNC_QUEUE_EMPTY)
+ space = list_empty(&cdma->sync_queue) ? 1 : 0;
+ else if (event == CDMA_EVENT_PUSH_BUFFER_SPACE) {
+ struct push_buffer *pb = &cdma->push_buffer;
+ space = host1x_pushbuffer_space(pb);
+ } else {
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
+ if (space)
+ return space;
+
+ trace_host1x_wait_cdma(dev_name(cdma_to_channel(cdma)->dev),
+ event);
+
+ /* If somebody has managed to already start waiting, yield */
+ if (cdma->event != CDMA_EVENT_NONE) {
+ mutex_unlock(&cdma->lock);
+ schedule();
+ mutex_lock(&cdma->lock);
+ continue;
+ }
+ cdma->event = event;
+
+ mutex_unlock(&cdma->lock);
+ down(&cdma->sem);
+ mutex_lock(&cdma->lock);
+ }
+ return 0;
+}
+
+/*
+ * Start timer that tracks the time spent by the job.
+ * Must be called with the cdma lock held.
+ */
+static void cdma_start_timer_locked(struct host1x_cdma *cdma,
+ struct host1x_job *job)
+{
+ struct host1x *host = cdma_to_host1x(cdma);
+
+ if (cdma->timeout.client) {
+ /* timer already started */
+ return;
+ }
+
+ cdma->timeout.client = job->client;
+ cdma->timeout.syncpt = host1x_syncpt_get(host, job->syncpt_id);
+ cdma->timeout.syncpt_val = job->syncpt_end;
+ cdma->timeout.start_ktime = ktime_get();
+
+ schedule_delayed_work(&cdma->timeout.wq,
+ msecs_to_jiffies(job->timeout));
+}
+
+/*
+ * Stop timer when a buffer submission completes.
+ * Must be called with the cdma lock held.
+ */
+static void stop_cdma_timer_locked(struct host1x_cdma *cdma)
+{
+ cancel_delayed_work(&cdma->timeout.wq);
+ cdma->timeout.client = 0;
+}
+
+/*
+ * For all sync queue entries that have already finished according to the
+ * current sync point registers:
+ * - unpin & unref their mems
+ * - pop their push buffer slots
+ * - remove them from the sync queue
+ * This is normally called from the host code's worker thread, but can be
+ * called manually if necessary.
+ * Must be called with the cdma lock held.
+ */
+static void update_cdma_locked(struct host1x_cdma *cdma)
+{
+ bool signal = false;
+ struct host1x *host1x = cdma_to_host1x(cdma);
+ struct host1x_job *job, *n;
+
+ /* If CDMA is stopped, queue is cleared and we can return */
+ if (!cdma->running)
+ return;
+
+ /*
+ * Walk the sync queue, reading the sync point registers as necessary,
+ * to consume as many sync queue entries as possible without blocking
+ */
+ list_for_each_entry_safe(job, n, &cdma->sync_queue, list) {
+ struct host1x_syncpt *sp =
+ host1x_syncpt_get(host1x, job->syncpt_id);
+
+ /* Check whether this syncpt has completed, and bail if not */
+ if (!host1x_syncpt_is_expired(sp, job->syncpt_end)) {
+ /* Start timer on next pending syncpt */
+ if (job->timeout)
+ cdma_start_timer_locked(cdma, job);
+ break;
+ }
+
+ /* Cancel timeout, when a buffer completes */
+ if (cdma->timeout.client)
+ stop_cdma_timer_locked(cdma);
+
+ /* Unpin the memory */
+ host1x_job_unpin(job);
+
+ /* Pop push buffer slots */
+ if (job->num_slots) {
+ struct push_buffer *pb = &cdma->push_buffer;
+ host1x_pushbuffer_pop(pb, job->num_slots);
+ if (cdma->event == CDMA_EVENT_PUSH_BUFFER_SPACE)
+ signal = true;
+ }
+
+ list_del(&job->list);
+ host1x_job_put(job);
+ }
+
+ if (cdma->event == CDMA_EVENT_SYNC_QUEUE_EMPTY &&
+ list_empty(&cdma->sync_queue))
+ signal = true;
+
+ if (signal) {
+ cdma->event = CDMA_EVENT_NONE;
+ up(&cdma->sem);
+ }
+}
+
+void host1x_cdma_update_sync_queue(struct host1x_cdma *cdma,
+ struct device *dev)
+{
+ u32 restart_addr;
+ u32 syncpt_incrs;
+ struct host1x_job *job = NULL;
+ u32 syncpt_val;
+ struct host1x *host1x = cdma_to_host1x(cdma);
+
+ syncpt_val = host1x_syncpt_load(cdma->timeout.syncpt);
+
+ dev_dbg(dev, "%s: starting cleanup (thresh %d)\n",
+ __func__, syncpt_val);
+
+ /*
+ * Move the sync_queue read pointer to the first entry that hasn't
+ * completed based on the current HW syncpt value. It's likely there
+ * won't be any (i.e. we're still at the head), but covers the case
+ * where a syncpt incr happens just prior/during the teardown.
+ */
+
+ dev_dbg(dev, "%s: skip completed buffers still in sync_queue\n",
+ __func__);
+
+ list_for_each_entry(job, &cdma->sync_queue, list) {
+ if (syncpt_val < job->syncpt_end)
+ break;
+
+ host1x_job_dump(dev, job);
+ }
+
+ /*
+ * Walk the sync_queue, first incrementing with the CPU syncpts that
+ * are partially executed (the first buffer) or fully skipped while
+ * still in the current context (slots are also NOP-ed).
+ *
+ * At the point contexts are interleaved, syncpt increments must be
+ * done inline with the pushbuffer from a GATHER buffer to maintain
+ * the order (slots are modified to be a GATHER of syncpt incrs).
+ *
+ * Note: save in restart_addr the location where the timed out buffer
+ * started in the PB, so we can start the refetch from there (with the
+ * modified NOP-ed PB slots). This lets things appear to have completed
+ * properly for this buffer and resources are freed.
+ */
+
+ dev_dbg(dev, "%s: perform CPU incr on pending same ctx buffers\n",
+ __func__);
+
+ if (!list_empty(&cdma->sync_queue))
+ restart_addr = job->first_get;
+ else
+ restart_addr = cdma->last_pos;
+
+ /* do CPU increments as long as this context continues */
+ list_for_each_entry_from(job, &cdma->sync_queue, list) {
+ /* different context, gets us out of this loop */
+ if (job->client != cdma->timeout.client)
+ break;
+
+ /* won't need a timeout when replayed */
+ job->timeout = 0;
+
+ syncpt_incrs = job->syncpt_end - syncpt_val;
+ dev_dbg(dev, "%s: CPU incr (%d)\n", __func__, syncpt_incrs);
+
+ host1x_job_dump(dev, job);
+
+ /* safe to use CPU to incr syncpts */
+ host1x_hw_cdma_timeout_cpu_incr(host1x, cdma, job->first_get,
+ syncpt_incrs, job->syncpt_end,
+ job->num_slots);
+
+ syncpt_val += syncpt_incrs;
+ }
+
+ /* The following sumbits from the same client may be dependent on the
+ * failed submit and therefore they may fail. Force a small timeout
+ * to make the queue cleanup faster */
+
+ list_for_each_entry_from(job, &cdma->sync_queue, list)
+ if (job->client == cdma->timeout.client)
+ job->timeout = min_t(unsigned int, job->timeout, 500);
+
+ dev_dbg(dev, "%s: finished sync_queue modification\n", __func__);
+
+ /* roll back DMAGET and start up channel again */
+ host1x_hw_cdma_resume(host1x, cdma, restart_addr);
+}
+
+/*
+ * Create a cdma
+ */
+int host1x_cdma_init(struct host1x_cdma *cdma)
+{
+ int err;
+
+ mutex_init(&cdma->lock);
+ sema_init(&cdma->sem, 0);
+
+ INIT_LIST_HEAD(&cdma->sync_queue);
+
+ cdma->event = CDMA_EVENT_NONE;
+ cdma->running = false;
+ cdma->torndown = false;
+
+ err = host1x_pushbuffer_init(&cdma->push_buffer);
+ if (err)
+ return err;
+ return 0;
+}
+
+/*
+ * Destroy a cdma
+ */
+int host1x_cdma_deinit(struct host1x_cdma *cdma)
+{
+ struct push_buffer *pb = &cdma->push_buffer;
+ struct host1x *host1x = cdma_to_host1x(cdma);
+
+ if (cdma->running) {
+ pr_warn("%s: CDMA still running\n", __func__);
+ return -EBUSY;
+ }
+
+ host1x_pushbuffer_destroy(pb);
+ host1x_hw_cdma_timeout_destroy(host1x, cdma);
+
+ return 0;
+}
+
+/*
+ * Begin a cdma submit
+ */
+int host1x_cdma_begin(struct host1x_cdma *cdma, struct host1x_job *job)
+{
+ struct host1x *host1x = cdma_to_host1x(cdma);
+
+ mutex_lock(&cdma->lock);
+
+ if (job->timeout) {
+ /* init state on first submit with timeout value */
+ if (!cdma->timeout.initialized) {
+ int err;
+ err = host1x_hw_cdma_timeout_init(host1x, cdma,
+ job->syncpt_id);
+ if (err) {
+ mutex_unlock(&cdma->lock);
+ return err;
+ }
+ }
+ }
+ if (!cdma->running)
+ host1x_hw_cdma_start(host1x, cdma);
+
+ cdma->slots_free = 0;
+ cdma->slots_used = 0;
+ cdma->first_get = cdma->push_buffer.pos;
+
+ trace_host1x_cdma_begin(dev_name(job->channel->dev));
+ return 0;
+}
+
+/*
+ * Push two words into a push buffer slot
+ * Blocks as necessary if the push buffer is full.
+ */
+void host1x_cdma_push(struct host1x_cdma *cdma, u32 op1, u32 op2)
+{
+ struct host1x *host1x = cdma_to_host1x(cdma);
+ struct push_buffer *pb = &cdma->push_buffer;
+ u32 slots_free = cdma->slots_free;
+
+ if (slots_free == 0) {
+ host1x_hw_cdma_flush(host1x, cdma);
+ slots_free = host1x_cdma_wait_locked(cdma,
+ CDMA_EVENT_PUSH_BUFFER_SPACE);
+ }
+ cdma->slots_free = slots_free - 1;
+ cdma->slots_used++;
+ host1x_pushbuffer_push(pb, op1, op2);
+}
+
+/*
+ * End a cdma submit
+ * Kick off DMA, add job to the sync queue, and a number of slots to be freed
+ * from the pushbuffer. The handles for a submit must all be pinned at the same
+ * time, but they can be unpinned in smaller chunks.
+ */
+void host1x_cdma_end(struct host1x_cdma *cdma,
+ struct host1x_job *job)
+{
+ struct host1x *host1x = cdma_to_host1x(cdma);
+ bool idle = list_empty(&cdma->sync_queue);
+
+ host1x_hw_cdma_flush(host1x, cdma);
+
+ job->first_get = cdma->first_get;
+ job->num_slots = cdma->slots_used;
+ host1x_job_get(job);
+ list_add_tail(&job->list, &cdma->sync_queue);
+
+ /* start timer on idle -> active transitions */
+ if (job->timeout && idle)
+ cdma_start_timer_locked(cdma, job);
+
+ trace_host1x_cdma_end(dev_name(job->channel->dev));
+ mutex_unlock(&cdma->lock);
+}
+
+/*
+ * Update cdma state according to current sync point values
+ */
+void host1x_cdma_update(struct host1x_cdma *cdma)
+{
+ mutex_lock(&cdma->lock);
+ update_cdma_locked(cdma);
+ mutex_unlock(&cdma->lock);
+}