On 28/06/2021 08:42, Boris Brezillon wrote:
> From: Steven Price <steven.pr...@arm.com>
>
> The hardware has a set of '_NEXT' registers that can hold a second job
> while the first is executing. Make use of these registers to enqueue a
> second job per slot.
>
> v3:
> * Fix the done/err job dequeuing logic to get a valid active state
> * Only enable the second slot on GPUs supporting jobchain disambiguation
> * Split interrupt handling in sub-functions
>
> Signed-off-by: Steven Price <steven.pr...@arm.com>
> Signed-off-by: Boris Brezillon <boris.brezil...@collabora.com>
One nit below...
> ---
> drivers/gpu/drm/panfrost/panfrost_device.h | 2 +-
> drivers/gpu/drm/panfrost/panfrost_job.c | 468 +++++++++++++++------
> 2 files changed, 351 insertions(+), 119 deletions(-)
>
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h
> b/drivers/gpu/drm/panfrost/panfrost_device.h
> index d91f71366214..81f81fc8650e 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_device.h
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.h
> @@ -101,7 +101,7 @@ struct panfrost_device {
>
> struct panfrost_job_slot *js;
>
> - struct panfrost_job *jobs[NUM_JOB_SLOTS];
> + struct panfrost_job *jobs[NUM_JOB_SLOTS][2];
> struct list_head scheduled_jobs;
>
> struct panfrost_perfcnt *perfcnt;
> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c
> b/drivers/gpu/drm/panfrost/panfrost_job.c
> index 979108dbc323..b965669a1fed 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_job.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_job.c
> @@ -4,6 +4,7 @@
> #include <linux/delay.h>
> #include <linux/interrupt.h>
> #include <linux/io.h>
> +#include <linux/iopoll.h>
> #include <linux/platform_device.h>
> #include <linux/pm_runtime.h>
> #include <linux/dma-resv.h>
> @@ -140,9 +141,52 @@ static void panfrost_job_write_affinity(struct
> panfrost_device *pfdev,
> job_write(pfdev, JS_AFFINITY_NEXT_HI(js), affinity >> 32);
> }
>
> +static u32
> +panfrost_get_job_chain_flag(const struct panfrost_job *job)
> +{
> + struct panfrost_fence *f = to_panfrost_fence(job->done_fence);
> +
> + if (!panfrost_has_hw_feature(job->pfdev,
> HW_FEATURE_JOBCHAIN_DISAMBIGUATION))
> + return 0;
> +
> + return (f->seqno & 1) ? JS_CONFIG_JOB_CHAIN_FLAG : 0;
> +}
> +
> +static struct panfrost_job *
> +panfrost_dequeue_job(struct panfrost_device *pfdev, int slot)
> +{
> + struct panfrost_job *job = pfdev->jobs[slot][0];
> +
> + WARN_ON(!job);
> + pfdev->jobs[slot][0] = pfdev->jobs[slot][1];
> + pfdev->jobs[slot][1] = NULL;
> +
> + return job;
> +}
> +
> +static unsigned int
> +panfrost_enqueue_job(struct panfrost_device *pfdev, int slot,
> + struct panfrost_job *job)
> +{
> + if (WARN_ON(!job))
> + return 0;
> +
> + if (!pfdev->jobs[slot][0]) {
> + pfdev->jobs[slot][0] = job;
> + return 0;
> + }
> +
> + WARN_ON(pfdev->jobs[slot][1]);
> + pfdev->jobs[slot][1] = job;
> + WARN_ON(panfrost_get_job_chain_flag(job) ==
> + panfrost_get_job_chain_flag(pfdev->jobs[slot][0]));
> + return 1;
> +}
> +
> static void panfrost_job_hw_submit(struct panfrost_job *job, int js)
> {
> struct panfrost_device *pfdev = job->pfdev;
> + unsigned int subslot;
> u32 cfg;
> u64 jc_head = job->jc;
> int ret;
> @@ -168,7 +212,8 @@ static void panfrost_job_hw_submit(struct panfrost_job
> *job, int js)
> * start */
> cfg |= JS_CONFIG_THREAD_PRI(8) |
> JS_CONFIG_START_FLUSH_CLEAN_INVALIDATE |
> - JS_CONFIG_END_FLUSH_CLEAN_INVALIDATE;
> + JS_CONFIG_END_FLUSH_CLEAN_INVALIDATE |
> + panfrost_get_job_chain_flag(job);
>
> if (panfrost_has_hw_feature(pfdev, HW_FEATURE_FLUSH_REDUCTION))
> cfg |= JS_CONFIG_ENABLE_FLUSH_REDUCTION;
> @@ -182,10 +227,17 @@ static void panfrost_job_hw_submit(struct panfrost_job
> *job, int js)
> job_write(pfdev, JS_FLUSH_ID_NEXT(js), job->flush_id);
>
> /* GO ! */
> - dev_dbg(pfdev->dev, "JS: Submitting atom %p to js[%d] with head=0x%llx",
> - job, js, jc_head);
>
> - job_write(pfdev, JS_COMMAND_NEXT(js), JS_COMMAND_START);
> + spin_lock(&pfdev->js->job_lock);
> + subslot = panfrost_enqueue_job(pfdev, js, job);
> + /* Don't queue the job if a reset is in progress */
> + if (!atomic_read(&pfdev->reset.pending)) {
> + job_write(pfdev, JS_COMMAND_NEXT(js), JS_COMMAND_START);
> + dev_dbg(pfdev->dev,
> + "JS: Submitting atom %p to js[%d][%d] with head=0x%llx
> AS %d",
> + job, js, subslot, jc_head, cfg & 0xf);
> + }
> + spin_unlock(&pfdev->js->job_lock);
> }
>
> static void panfrost_acquire_object_fences(struct drm_gem_object **bos,
> @@ -343,7 +395,11 @@ static struct dma_fence *panfrost_job_run(struct
> drm_sched_job *sched_job)
> if (unlikely(job->base.s_fence->finished.error))
> return NULL;
>
> - pfdev->jobs[slot] = job;
> + /* Nothing to execute: can happen if the job has finished while
> + * we were resetting the GPU.
> + */
> + if (!job->jc)
> + return NULL;
>
> fence = panfrost_fence_create(pfdev, slot);
> if (IS_ERR(fence))
> @@ -371,11 +427,218 @@ void panfrost_job_enable_interrupts(struct
> panfrost_device *pfdev)
> job_write(pfdev, JOB_INT_MASK, irq_mask);
> }
>
> -static void panfrost_reset(struct panfrost_device *pfdev,
> - struct drm_sched_job *bad)
> +static void panfrost_job_handle_err(struct panfrost_device *pfdev,
> + struct panfrost_job *job,
> + unsigned int js)
> {
> - unsigned int i;
> + u32 js_status = job_read(pfdev, JS_STATUS(js));
> + const char *exception_name = panfrost_exception_name(js_status);
> + bool signal_fence = true;
> +
> + if (js_status < DRM_PANFROST_EXCEPTION_JOB_CONFIG_FAULT) {
> + dev_dbg(pfdev->dev, "js event, js=%d, status=%s, head=0x%x,
> tail=0x%x",
> + js, exception_name,
> + job_read(pfdev, JS_HEAD_LO(js)),
> + job_read(pfdev, JS_TAIL_LO(js)));
> + } else {
> + dev_err(pfdev->dev, "js fault, js=%d, status=%s, head=0x%x,
> tail=0x%x",
> + js, exception_name,
> + job_read(pfdev, JS_HEAD_LO(js)),
> + job_read(pfdev, JS_TAIL_LO(js)));
> + }
> +
> + if (js_status == DRM_PANFROST_EXCEPTION_STOPPED) {
> + /* Update the job head so we can resume */
> + job->jc = job_read(pfdev, JS_TAIL_LO(js)) |
> + ((u64)job_read(pfdev, JS_TAIL_HI(js)) << 32);
> +
> + /* The job will be resumed, don't signal the fence */
> + signal_fence = false;
> + } else if (js_status == DRM_PANFROST_EXCEPTION_TERMINATED) {
> + /* Job has been hard-stopped, flag it as canceled */
> + dma_fence_set_error(job->done_fence, -ECANCELED);
> + job->jc = 0;
> + } else if (js_status >= DRM_PANFROST_EXCEPTION_JOB_CONFIG_FAULT) {
> + /* We might want to provide finer-grained error code based on
> + * the exception type, but unconditionally setting to EINVAL
> + * is good enough for now.
> + */
> + dma_fence_set_error(job->done_fence, -EINVAL);
> + job->jc = 0;
> + }
> +
> + panfrost_mmu_as_put(pfdev, job->file_priv->mmu);
> + panfrost_devfreq_record_idle(&pfdev->pfdevfreq);
> +
> + if (signal_fence)
> + dma_fence_signal_locked(job->done_fence);
> +
> + pm_runtime_put_autosuspend(pfdev->dev);
> +
> + if (panfrost_exception_needs_reset(pfdev, js_status)) {
> + atomic_set(&pfdev->reset.pending, 1);
> + drm_sched_fault(&pfdev->js->queue[js].sched);
> + }
> +}
> +
> +static void panfrost_job_handle_done(struct panfrost_device *pfdev,
> + struct panfrost_job *job)
> +{
> + /* Set ->jc to 0 to avoid re-submitting an already finished job (can
> + * happen when we receive the DONE interrupt while doing a GPU reset).
> + */
> + job->jc = 0;
> + panfrost_mmu_as_put(pfdev, job->file_priv->mmu);
> + panfrost_devfreq_record_idle(&pfdev->pfdevfreq);
> +
> + dma_fence_signal_locked(job->done_fence);
> + pm_runtime_put_autosuspend(pfdev->dev);
> +}
> +
> +static void panfrost_job_handle_irq(struct panfrost_device *pfdev, u32
> status)
> +{
> + struct panfrost_job *done[NUM_JOB_SLOTS][2] = {};
> + struct panfrost_job *failed[NUM_JOB_SLOTS] = {};
> + u32 js_state = 0, js_events = 0;
> + unsigned int i, j;
> +
> + /* First we collect all failed/done jobs. */
> + while (status) {
> + u32 js_state_mask = 0;
> +
> + for (j = 0; j < NUM_JOB_SLOTS; j++) {
> + if (status & MK_JS_MASK(j))
> + js_state_mask |= MK_JS_MASK(j);
> +
> + if (status & JOB_INT_MASK_DONE(j)) {
> + if (done[j][0])
> + done[j][1] =
> panfrost_dequeue_job(pfdev, j);
> + else
> + done[j][0] =
> panfrost_dequeue_job(pfdev, j);
> + }
> +
> + if (status & JOB_INT_MASK_ERR(j)) {
> + /* Cancel the next submission. Will be submitted
> + * after we're done handling this failure if
> + * there's no reset pending.
> + */
> + job_write(pfdev, JS_COMMAND_NEXT(j),
> JS_COMMAND_NOP);
> + failed[j] = panfrost_dequeue_job(pfdev, j);
> + }
> + }
> +
> + /* JS_STATE is sampled when JOB_INT_CLEAR is written.
> + * For each BIT(slot) or BIT(slot + 16) bit written to
> + * JOB_INT_CLEAR, the corresponding bits in JS_STATE
> + * (BIT(slot) and BIT(slot + 16)) are updated, but this
> + * is racy. If we only have one job done at the time we
> + * read JOB_INT_RAWSTAT but the second job fails before we
> + * clear the status, we end up with a status containing
> + * only the DONE bit and consider both jobs as DONE since
> + * JS_STATE reports both NEXT and CURRENT as inactive.
> + * To prevent that, let's repeat this clear+read steps
> + * until status is 0.
> + */
> + job_write(pfdev, JOB_INT_CLEAR, status);
> + js_state &= ~js_state_mask;
> + js_state |= job_read(pfdev, JOB_INT_JS_STATE) & js_state_mask;
> + js_events |= status;
> + status = job_read(pfdev, JOB_INT_RAWSTAT);
> + }
> +
> + /* Then we handle the dequeued jobs. */
> + for (j = 0; j < NUM_JOB_SLOTS; j++) {
> + if (!(js_events & MK_JS_MASK(j)))
> + continue;
> +
> + if (failed[j]) {
> + panfrost_job_handle_err(pfdev, failed[j], j);
> + } else if (pfdev->jobs[j][0] && !(js_state & MK_JS_MASK(j))) {
> + /* When the current job doesn't fail, the JM dequeues
> + * the next job without waiting for an ACK, this means
> + * we can have 2 jobs dequeued and only catch the
> + * interrupt when the second one is done. If both slots
> + * are inactive, but one job remains in pfdev->jobs[j],
> + * consider it done. Of course that doesn't apply if a
> + * failure happened since we cancelled execution of the
> + * job in _NEXT (see above).
> + */
> + if (WARN_ON(!done[j][0]))
> + done[j][0] = panfrost_dequeue_job(pfdev, j);
> + else
> + done[j][1] = panfrost_dequeue_job(pfdev, j);
> + }
> +
> + for (i = 0; i < ARRAY_SIZE(done[0]) && done[j][i]; i++)
> + panfrost_job_handle_done(pfdev, done[j][i]);
> + }
> +
> + /* And finally we requeue jobs that were waiting in the second slot
> + * and have been stopped if we detected a failure on the first slot.
> + */
> + for (j = 0; j < NUM_JOB_SLOTS; j++) {
> + if (!(js_events & MK_JS_MASK(j)))
> + continue;
> +
> + if (!failed[j] || !pfdev->jobs[j][0])
> + continue;
> +
> + if (pfdev->jobs[j][0]->jc == 0) {
> + /* The job was cancelled, signal the fence now */
> + struct panfrost_job *canceled =
> panfrost_dequeue_job(pfdev, j);
> +
> + dma_fence_set_error(canceled->done_fence, -ECANCELED);
> + panfrost_job_handle_done(pfdev, canceled);
> + } else if (!atomic_read(&pfdev->reset.pending)) {
> + /* Requeue the job we removed if no reset is pending */
> + job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_START);
> + }
> + }
> +}
> +
> +static void panfrost_job_handle_irqs(struct panfrost_device *pfdev)
> +{
> + u32 status = job_read(pfdev, JOB_INT_RAWSTAT);
> +
> + while (status) {
> + pm_runtime_mark_last_busy(pfdev->dev);
> +
> + spin_lock(&pfdev->js->job_lock);
> + panfrost_job_handle_irq(pfdev, status);
> + spin_unlock(&pfdev->js->job_lock);
> + status = job_read(pfdev, JOB_INT_RAWSTAT);
> + }
> +}
> +
> +static u32 panfrost_active_slots(struct panfrost_device *pfdev,
> + u32 *js_state_mask, u32 js_state)
> +{
> + u32 rawstat;
> +
> + if (!(js_state & *js_state_mask))
> + return 0;
> +
> + rawstat = job_read(pfdev, JOB_INT_RAWSTAT);
> + if (rawstat) {
> + unsigned int i;
> +
> + for (i = 0; i < NUM_JOB_SLOTS; i++) {
> + if (rawstat & MK_JS_MASK(i))
> + *js_state_mask &= ~MK_JS_MASK(i);
> + }
> + }
> +
> + return js_state & *js_state_mask;
> +}
> +
> +static void
> +panfrost_reset(struct panfrost_device *pfdev,
> + struct drm_sched_job *bad)
> +{
> + u32 js_state, js_state_mask = 0xffffffff;
> + unsigned int i, j;
> bool cookie;
> + int ret;
>
> if (!atomic_read(&pfdev->reset.pending))
> return;
> @@ -407,21 +670,46 @@ static void panfrost_reset(struct panfrost_device
> *pfdev,
> job_write(pfdev, JOB_INT_MASK, 0);
> synchronize_irq(pfdev->js->irq);
>
> - /* Schedulers are stopped and interrupts are masked+flushed, we don't
> - * need to protect the 'evict unfinished jobs' lock with the job_lock.
> + for (i = 0; i < NUM_JOB_SLOTS; i++) {
> + /* Cancel the next job and soft-stop the running job. */
> + job_write(pfdev, JS_COMMAND_NEXT(i), JS_COMMAND_NOP);
> + job_write(pfdev, JS_COMMAND(i), JS_COMMAND_SOFT_STOP);
> + }
> +
> + /* Wait at most 10ms for soft-stops to complete */
> + ret = readl_poll_timeout(pfdev->iomem + JOB_INT_JS_STATE, js_state,
> + !panfrost_active_slots(pfdev, &js_state_mask,
> js_state),
> + 10, 10000);
> +
> + if (ret)
> + dev_err(pfdev->dev, "Soft-stop failed\n");
> +
> + /* Handle the remaining interrupts before we reset. */
> + panfrost_job_handle_irqs(pfdev);
> +
> + /* Remaining interrupts have been handled, but we might still have
> + * stuck jobs. Let's make sure the PM counters stay balanced by
> + * manually calling pm_runtime_put_noidle() and
> + * panfrost_devfreq_record_idle() for each stuck job.
> */
> spin_lock(&pfdev->js->job_lock);
> for (i = 0; i < NUM_JOB_SLOTS; i++) {
> - if (pfdev->jobs[i]) {
> + for (j = 0; j < ARRAY_SIZE(pfdev->jobs[0]) &&
> pfdev->jobs[i][j]; j++) {
> pm_runtime_put_noidle(pfdev->dev);
> panfrost_devfreq_record_idle(&pfdev->pfdevfreq);
> - pfdev->jobs[i] = NULL;
> }
> }
> + memset(pfdev->jobs, 0, sizeof(pfdev->jobs));
> spin_unlock(&pfdev->js->job_lock);
>
> + /* Proceed with reset now. */
> panfrost_device_reset(pfdev);
>
> + /* panfrost_device_reset() unmasks job interrupts, but we want to
> + * keep them masked a bit longer.
> + */
> + job_write(pfdev, JOB_INT_MASK, 0);
> +
> /* GPU has been reset, we can cancel timeout/fault work that may have
> * been queued in the meantime and clear the reset pending bit.
> */
> @@ -429,7 +717,6 @@ static void panfrost_reset(struct panfrost_device *pfdev,
> for (i = 0; i < NUM_JOB_SLOTS; i++)
> cancel_delayed_work(&pfdev->js->queue[i].sched.work_tdr);
>
> -
> /* Now resubmit jobs that were previously queued but didn't have a
> * chance to finish.
> * FIXME: We temporarily get out of the DMA fence signalling section
> @@ -442,9 +729,15 @@ static void panfrost_reset(struct panfrost_device *pfdev,
> drm_sched_resubmit_jobs(&pfdev->js->queue[i].sched);
> cookie = dma_fence_begin_signalling();
>
> + /* Restart the schedulers */
> for (i = 0; i < NUM_JOB_SLOTS; i++)
> drm_sched_start(&pfdev->js->queue[i].sched, true);
>
> + /* Re-enable job interrupts now that everything has been restarted. */
> + job_write(pfdev, JOB_INT_MASK,
> + GENMASK(16 + NUM_JOB_SLOTS - 1, 16) |
> + GENMASK(NUM_JOB_SLOTS - 1, 0));
> +
> dma_fence_end_signalling(cookie);
> }
>
> @@ -476,6 +769,14 @@ static enum drm_gpu_sched_stat
> panfrost_job_timedout(struct drm_sched_job
> return DRM_GPU_SCHED_STAT_NOMINAL;
> }
>
> +static void panfrost_reset_work(struct work_struct *work)
> +{
> + struct panfrost_device *pfdev;
> +
> + pfdev = container_of(work, struct panfrost_device, reset.work);
> + panfrost_reset(pfdev, NULL);
> +}
> +
> static const struct drm_sched_backend_ops panfrost_sched_ops = {
> .dependency = panfrost_job_dependency,
> .run_job = panfrost_job_run,
> @@ -483,100 +784,11 @@ static const struct drm_sched_backend_ops
> panfrost_sched_ops = {
> .free_job = panfrost_job_free
> };
>
> -static void panfrost_job_handle_irq(struct panfrost_device *pfdev, u32
> status)
> -{
> - int j;
> -
> - dev_dbg(pfdev->dev, "jobslot irq status=%x\n", status);
> -
> - for (j = 0; status; j++) {
> - u32 mask = MK_JS_MASK(j);
> -
> - if (!(status & mask))
> - continue;
> -
> - job_write(pfdev, JOB_INT_CLEAR, mask);
> -
> - if (status & JOB_INT_MASK_ERR(j)) {
> - u32 js_status = job_read(pfdev, JS_STATUS(j));
> - const char *exception_name =
> panfrost_exception_name(js_status);
> -
> - job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_NOP);
> -
> - if (js_status <
> DRM_PANFROST_EXCEPTION_JOB_CONFIG_FAULT) {
> - dev_dbg(pfdev->dev, "js interrupt, js=%d,
> status=%s, head=0x%x, tail=0x%x",
> - j, exception_name,
> - job_read(pfdev, JS_HEAD_LO(j)),
> - job_read(pfdev, JS_TAIL_LO(j)));
> - } else {
> - dev_err(pfdev->dev, "js fault, js=%d,
> status=%s, head=0x%x, tail=0x%x",
> - j, exception_name,
> - job_read(pfdev, JS_HEAD_LO(j)),
> - job_read(pfdev, JS_TAIL_LO(j)));
> - }
> -
> - /* If we need a reset, signal it to the timeout
> - * handler, otherwise, update the fence error field and
> - * signal the job fence.
> - */
> - if (panfrost_exception_needs_reset(pfdev, js_status)) {
> - drm_sched_fault(&pfdev->js->queue[j].sched);
> - } else {
> - int error = 0;
> -
> - if (js_status ==
> DRM_PANFROST_EXCEPTION_TERMINATED)
> - error = -ECANCELED;
> - else if (js_status >=
> DRM_PANFROST_EXCEPTION_JOB_CONFIG_FAULT)
> - error = -EINVAL;
> -
> - if (error)
> -
> dma_fence_set_error(pfdev->jobs[j]->done_fence, error);
> -
> - status |= JOB_INT_MASK_DONE(j);
> - }
> - }
> -
> - if (status & JOB_INT_MASK_DONE(j)) {
> - struct panfrost_job *job;
> -
> - job = pfdev->jobs[j];
> - /* The only reason this job could be NULL is if the
> - * job IRQ handler is called just after the
> - * in-flight job eviction in the reset path, and
> - * this shouldn't happen because the job IRQ has
> - * been masked and synchronized when this eviction
> - * happens.
> - */
> - WARN_ON(!job);
> - if (job) {
> - pfdev->jobs[j] = NULL;
> -
> - panfrost_mmu_as_put(pfdev, job->file_priv->mmu);
> - panfrost_devfreq_record_idle(&pfdev->pfdevfreq);
> -
> - dma_fence_signal_locked(job->done_fence);
> - pm_runtime_put_autosuspend(pfdev->dev);
> - }
> - }
> -
> - status &= ~mask;
> - }
> -}
> -
> static irqreturn_t panfrost_job_irq_handler_thread(int irq, void *data)
> {
> struct panfrost_device *pfdev = data;
> - u32 status = job_read(pfdev, JOB_INT_RAWSTAT);
> -
> - while (status) {
> - pm_runtime_mark_last_busy(pfdev->dev);
> -
> - spin_lock(&pfdev->js->job_lock);
> - panfrost_job_handle_irq(pfdev, status);
> - spin_unlock(&pfdev->js->job_lock);
> - status = job_read(pfdev, JOB_INT_RAWSTAT);
> - }
>
> + panfrost_job_handle_irqs(pfdev);
> job_write(pfdev, JOB_INT_MASK,
> GENMASK(16 + NUM_JOB_SLOTS - 1, 16) |
> GENMASK(NUM_JOB_SLOTS - 1, 0));
> @@ -595,26 +807,24 @@ static irqreturn_t panfrost_job_irq_handler(int irq,
> void *data)
> return IRQ_WAKE_THREAD;
> }
>
> -static void panfrost_reset_work(struct work_struct *work)
> -{
> - struct panfrost_device *pfdev = container_of(work,
> - struct panfrost_device,
> - reset.work);
> -
> - panfrost_reset(pfdev, NULL);
> -}
> -
> int panfrost_job_init(struct panfrost_device *pfdev)
> {
> struct panfrost_job_slot *js;
> + unsigned int nslots = 2;
> int ret, j;
>
> - INIT_WORK(&pfdev->reset.work, panfrost_reset_work);
> + /* All GPUs have twnslotsueue, but without jobchain
^^^^^^^^^^^^
It's a made up word ;)
Also the use of "slot" here is confusing because it's referring to hw
submission entries in the call to drm_sched_init() and not the "job
slots" that the HW has (Mali GPUs have 3 slots).
Thanks,
Steve
> + * disambiguation stopping the right job in the close path is tricky,
> + * so let's just advertize one slot in that case.
> + */
> + if (!panfrost_has_hw_feature(pfdev, HW_FEATURE_JOBCHAIN_DISAMBIGUATION))
> + nslots = 1;
>
> pfdev->js = js = devm_kzalloc(pfdev->dev, sizeof(*js), GFP_KERNEL);
> if (!js)
> return -ENOMEM;
>
> + INIT_WORK(&pfdev->reset.work, panfrost_reset_work);
> spin_lock_init(&js->job_lock);
>
> js->irq = platform_get_irq_byname(to_platform_device(pfdev->dev),
> "job");
> @@ -640,7 +850,7 @@ int panfrost_job_init(struct panfrost_device *pfdev)
>
> ret = drm_sched_init(&js->queue[j].sched,
> &panfrost_sched_ops,
> - 1, 0,
> + nslots, 0,
> msecs_to_jiffies(JOB_TIMEOUT_MS),
> pfdev->reset.wq,
> NULL, "pan_js");
> @@ -707,12 +917,34 @@ void panfrost_job_close(struct panfrost_file_priv
> *panfrost_priv)
> spin_lock(&pfdev->js->job_lock);
> for (i = 0; i < NUM_JOB_SLOTS; i++) {
> struct drm_sched_entity *entity =
> &panfrost_priv->sched_entity[i];
> - struct panfrost_job *job = pfdev->jobs[i];
> + int j;
>
> - if (!job || job->base.entity != entity)
> - continue;
> + for (j = ARRAY_SIZE(pfdev->jobs[0]) - 1; j >= 0; j--) {
> + struct panfrost_job *job = pfdev->jobs[i][j];
> + u32 cmd;
>
> - job_write(pfdev, JS_COMMAND(i), JS_COMMAND_HARD_STOP);
> + if (!job || job->base.entity != entity)
> + continue;
> +
> + if (j == 1) {
> + /* Try to cancel the job before it starts */
> + job_write(pfdev, JS_COMMAND_NEXT(i),
> JS_COMMAND_NOP);
> + /* Reset the job head so it doesn't get
> restarted if
> + * the job in the first slot failed.
> + */
> + job->jc = 0;
> + }
> +
> + if (panfrost_has_hw_feature(pfdev,
> HW_FEATURE_JOBCHAIN_DISAMBIGUATION)) {
> + cmd = panfrost_get_job_chain_flag(job) ?
> + JS_COMMAND_HARD_STOP_1 :
> + JS_COMMAND_HARD_STOP_0;
> + } else {
> + cmd = JS_COMMAND_HARD_STOP;
> + }
> +
> + job_write(pfdev, JS_COMMAND(i), cmd);
> + }
> }
> spin_unlock(&pfdev->js->job_lock);
> }
>
