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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpu/host1x/cdma.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/host1x/cdma.c')
-rw-r--r--drivers/gpu/host1x/cdma.c685
1 files changed, 685 insertions, 0 deletions
diff --git a/drivers/gpu/host1x/cdma.c b/drivers/gpu/host1x/cdma.c
new file mode 100644
index 000000000..103fda055
--- /dev/null
+++ b/drivers/gpu/host1x/cdma.c
@@ -0,0 +1,685 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Tegra host1x Command DMA
+ *
+ * Copyright (c) 2010-2013, NVIDIA Corporation.
+ */
+
+
+#include <asm/cacheflush.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/host1x.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 "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.
+ */
+
+/*
+ * Typically the commands written into the push buffer are a pair of words. We
+ * use slots to represent each of these pairs and to simplify things. Note the
+ * strange number of slots allocated here. 512 slots will fit exactly within a
+ * single memory page. We also need one additional word at the end of the push
+ * buffer for the RESTART opcode that will instruct the CDMA to jump back to
+ * the beginning of the push buffer. With 512 slots, this means that we'll use
+ * 2 memory pages and waste 4092 bytes of the second page that will never be
+ * used.
+ */
+#define HOST1X_PUSHBUFFER_SLOTS 511
+
+/*
+ * 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->mapped)
+ return;
+
+ if (host1x->domain) {
+ iommu_unmap(host1x->domain, pb->dma, pb->alloc_size);
+ free_iova(&host1x->iova, iova_pfn(&host1x->iova, pb->dma));
+ }
+
+ dma_free_wc(host1x->dev, pb->alloc_size, 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);
+ struct iova *alloc;
+ u32 size;
+ int err;
+
+ pb->mapped = NULL;
+ pb->phys = 0;
+ pb->size = HOST1X_PUSHBUFFER_SLOTS * 8;
+
+ size = pb->size + 4;
+
+ /* initialize buffer pointers */
+ pb->fence = pb->size - 8;
+ pb->pos = 0;
+
+ if (host1x->domain) {
+ unsigned long shift;
+
+ size = iova_align(&host1x->iova, size);
+
+ pb->mapped = dma_alloc_wc(host1x->dev, size, &pb->phys,
+ GFP_KERNEL);
+ if (!pb->mapped)
+ return -ENOMEM;
+
+ shift = iova_shift(&host1x->iova);
+ alloc = alloc_iova(&host1x->iova, size >> shift,
+ host1x->iova_end >> shift, true);
+ if (!alloc) {
+ err = -ENOMEM;
+ goto iommu_free_mem;
+ }
+
+ pb->dma = iova_dma_addr(&host1x->iova, alloc);
+ err = iommu_map(host1x->domain, pb->dma, pb->phys, size,
+ IOMMU_READ);
+ if (err)
+ goto iommu_free_iova;
+ } else {
+ pb->mapped = dma_alloc_wc(host1x->dev, size, &pb->phys,
+ GFP_KERNEL);
+ if (!pb->mapped)
+ return -ENOMEM;
+
+ pb->dma = pb->phys;
+ }
+
+ pb->alloc_size = size;
+
+ host1x_hw_pushbuffer_init(host1x, pb);
+
+ return 0;
+
+iommu_free_iova:
+ __free_iova(&host1x->iova, alloc);
+iommu_free_mem:
+ dma_free_wc(host1x->dev, size, pb->mapped, pb->phys);
+
+ return err;
+}
+
+/*
+ * 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 *p = (u32 *)((void *)pb->mapped + pb->pos);
+
+ WARN_ON(pb->pos == pb->fence);
+ *(p++) = op1;
+ *(p++) = op2;
+ pb->pos += 8;
+
+ if (pb->pos >= pb->size)
+ pb->pos -= pb->size;
+}
+
+/*
+ * 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 += slots * 8;
+
+ if (pb->fence >= pb->size)
+ pb->fence -= pb->size;
+}
+
+/*
+ * Return the number of two word slots free in the push buffer
+ */
+static u32 host1x_pushbuffer_space(struct push_buffer *pb)
+{
+ unsigned int fence = pb->fence;
+
+ if (pb->fence < pb->pos)
+ fence += pb->size;
+
+ return (fence - pb->pos) / 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 (;;) {
+ struct push_buffer *pb = &cdma->push_buffer;
+ unsigned int space;
+
+ switch (event) {
+ case CDMA_EVENT_SYNC_QUEUE_EMPTY:
+ space = list_empty(&cdma->sync_queue) ? 1 : 0;
+ break;
+
+ case CDMA_EVENT_PUSH_BUFFER_SPACE:
+ space = host1x_pushbuffer_space(pb);
+ break;
+
+ default:
+ 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);
+ wait_for_completion(&cdma->complete);
+ mutex_lock(&cdma->lock);
+ }
+
+ return 0;
+}
+
+/*
+ * Sleep (if necessary) until the push buffer has enough free space.
+ *
+ * Must be called with the cdma lock held.
+ */
+static int host1x_cdma_wait_pushbuffer_space(struct host1x *host1x,
+ struct host1x_cdma *cdma,
+ unsigned int needed)
+{
+ while (true) {
+ struct push_buffer *pb = &cdma->push_buffer;
+ unsigned int space;
+
+ space = host1x_pushbuffer_space(pb);
+ if (space >= needed)
+ break;
+
+ trace_host1x_wait_cdma(dev_name(cdma_to_channel(cdma)->dev),
+ CDMA_EVENT_PUSH_BUFFER_SPACE);
+
+ host1x_hw_cdma_flush(host1x, cdma);
+
+ /* 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 = CDMA_EVENT_PUSH_BUFFER_SPACE;
+
+ mutex_unlock(&cdma->lock);
+ wait_for_completion(&cdma->complete);
+ 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)
+{
+ if (cdma->timeout.client) {
+ /* timer already started */
+ return;
+ }
+
+ cdma->timeout.client = job->client;
+ cdma->timeout.syncpt = job->syncpt;
+ 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 = NULL;
+}
+
+/*
+ * 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_job *job, *n;
+
+ /*
+ * 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 = job->syncpt;
+
+ /* Check whether this syncpt has completed, and bail if not */
+ if (!host1x_syncpt_is_expired(sp, job->syncpt_end) &&
+ !job->cancelled) {
+ /* 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;
+ complete(&cdma->complete);
+ }
+}
+
+void host1x_cdma_update_sync_queue(struct host1x_cdma *cdma,
+ struct device *dev)
+{
+ struct host1x *host1x = cdma_to_host1x(cdma);
+ u32 restart_addr, syncpt_incrs, syncpt_val;
+ struct host1x_job *job, *next_job = NULL;
+
+ 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) {
+
+ if (!list_is_last(&job->list, &cdma->sync_queue))
+ next_job = list_next_entry(job, list);
+
+ goto syncpt_incr;
+ }
+
+ host1x_job_dump(dev, job);
+ }
+
+ /* all jobs have been completed */
+ job = NULL;
+
+syncpt_incr:
+
+ /*
+ * Increment with CPU the remaining syncpts of a partially executed job.
+ *
+ * CDMA will continue execution starting with the next job or will get
+ * into idle state.
+ */
+ if (next_job)
+ restart_addr = next_job->first_get;
+ else
+ restart_addr = cdma->last_pos;
+
+ if (!job)
+ goto resume;
+
+ /* do CPU increments for the remaining syncpts */
+ if (job->syncpt_recovery) {
+ dev_dbg(dev, "%s: perform CPU incr on pending buffers\n",
+ __func__);
+
+ /* 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);
+
+ dev_dbg(dev, "%s: finished sync_queue modification\n",
+ __func__);
+ } else {
+ struct host1x_job *failed_job = job;
+
+ host1x_job_dump(dev, job);
+
+ host1x_syncpt_set_locked(job->syncpt);
+ failed_job->cancelled = true;
+
+ list_for_each_entry_continue(job, &cdma->sync_queue, list) {
+ unsigned int i;
+
+ if (job->syncpt != failed_job->syncpt)
+ continue;
+
+ for (i = 0; i < job->num_slots; i++) {
+ unsigned int slot = (job->first_get/8 + i) %
+ HOST1X_PUSHBUFFER_SLOTS;
+ u32 *mapped = cdma->push_buffer.mapped;
+
+ /*
+ * Overwrite opcodes with 0 word writes
+ * to offset 0xbad. This does nothing but
+ * has a easily detected signature in debug
+ * traces.
+ *
+ * On systems with MLOCK enforcement enabled,
+ * the above 0 word writes would fall foul of
+ * the enforcement. As such, in the first slot
+ * put a RESTART_W opcode to the beginning
+ * of the next job. We don't use this for older
+ * chips since those only support the RESTART
+ * opcode with inconvenient alignment requirements.
+ */
+ if (i == 0 && host1x->info->has_wide_gather) {
+ unsigned int next_job = (job->first_get/8 + job->num_slots)
+ % HOST1X_PUSHBUFFER_SLOTS;
+ mapped[2*slot+0] = (0xd << 28) | (next_job * 2);
+ mapped[2*slot+1] = 0x0;
+ } else {
+ mapped[2*slot+0] = 0x1bad0000;
+ mapped[2*slot+1] = 0x1bad0000;
+ }
+ }
+
+ job->cancelled = true;
+ }
+
+ wmb();
+
+ update_cdma_locked(cdma);
+ }
+
+resume:
+ /* 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);
+ init_completion(&cdma->complete);
+
+ 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);
+
+ /*
+ * Check if syncpoint was locked due to previous job timeout.
+ * This needs to be done within the cdma lock to avoid a race
+ * with the timeout handler.
+ */
+ if (job->syncpt->locked) {
+ mutex_unlock(&cdma->lock);
+ return -EPERM;
+ }
+
+ 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);
+ 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 (host1x_debug_trace_cmdbuf)
+ trace_host1x_cdma_push(dev_name(cdma_to_channel(cdma)->dev),
+ op1, op2);
+
+ 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);
+}
+
+/*
+ * Push four words into two consecutive push buffer slots. Note that extra
+ * care needs to be taken not to split the two slots across the end of the
+ * push buffer. Otherwise the RESTART opcode at the end of the push buffer
+ * that ensures processing will restart at the beginning will break up the
+ * four words.
+ *
+ * Blocks as necessary if the push buffer is full.
+ */
+void host1x_cdma_push_wide(struct host1x_cdma *cdma, u32 op1, u32 op2,
+ u32 op3, u32 op4)
+{
+ struct host1x_channel *channel = cdma_to_channel(cdma);
+ struct host1x *host1x = cdma_to_host1x(cdma);
+ struct push_buffer *pb = &cdma->push_buffer;
+ unsigned int space = cdma->slots_free;
+ unsigned int needed = 2, extra = 0;
+
+ if (host1x_debug_trace_cmdbuf)
+ trace_host1x_cdma_push_wide(dev_name(channel->dev), op1, op2,
+ op3, op4);
+
+ /* compute number of extra slots needed for padding */
+ if (pb->pos + 16 > pb->size) {
+ extra = (pb->size - pb->pos) / 8;
+ needed += extra;
+ }
+
+ host1x_cdma_wait_pushbuffer_space(host1x, cdma, needed);
+ space = host1x_pushbuffer_space(pb);
+
+ cdma->slots_free = space - needed;
+ cdma->slots_used += needed;
+
+ if (extra > 0) {
+ /*
+ * If there isn't enough space at the tail of the pushbuffer,
+ * insert a RESTART(0) here to go back to the beginning.
+ * The code above adjusted the indexes appropriately.
+ */
+ host1x_pushbuffer_push(pb, (0x5 << 28), 0xdead0000);
+ }
+
+ host1x_pushbuffer_push(pb, op1, op2);
+ host1x_pushbuffer_push(pb, op3, op4);
+}
+
+/*
+ * 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);
+}