linux/drivers/gpu/host1x/cdma.c
Thierry Reding 0169b93f44 gpu: host1x: Make mapped field of push buffers void *
This reduces the amount of casting that needs to be done to get rid of
annoying warnings on 64-bit builds.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-11-13 16:11:35 +01:00

492 lines
12 KiB
C

/*
* 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/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.
*/
#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 *)((void *)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 (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);
}
/*
* 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);
}