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gpu: host1x: Add syncpoint wait and interrupts

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Add support for sync point interrupts, and sync point wait. Sync
point wait used interrupts for unblocking wait.

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>
This commit is contained in:
Terje Bergstrom 2013-03-22 16:34:02 +02:00 committed by Thierry Reding
parent 7547168743
commit 7ede0b0bf3
10 changed files with 846 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
drivers/gpu/host1x/Makefile
View File

@ -3,6 +3,7 @@ ccflags-y = -Idrivers/gpu/host1x
host1x-y = \
syncpt.o \
dev.o \
intr.o \
hw/host1x01.o
obj-$(CONFIG_TEGRA_HOST1X) += host1x.o

12
drivers/gpu/host1x/dev.c
View File

@ -28,6 +28,7 @@
#include <trace/events/host1x.h>
#include "dev.h"
#include "intr.h"
#include "hw/host1x01.h"
void host1x_sync_writel(struct host1x *host1x, u32 v, u32 r)
@ -123,13 +124,24 @@ static int host1x_probe(struct platform_device *pdev)
return err;
}
err = host1x_intr_init(host, syncpt_irq);
if (err) {
dev_err(&pdev->dev, "failed to initialize interrupts\n");
goto fail_deinit_syncpt;
}
return 0;
fail_deinit_syncpt:
host1x_syncpt_deinit(host);
return err;
}
static int __exit host1x_remove(struct platform_device *pdev)
{
struct host1x *host = platform_get_drvdata(pdev);
host1x_intr_deinit(host);
host1x_syncpt_deinit(host);
clk_disable_unprepare(host->clk);

51
drivers/gpu/host1x/dev.h
View File

@ -21,6 +21,7 @@
#include <linux/device.h>
#include "syncpt.h"
#include "intr.h"
struct host1x_syncpt;
@ -33,6 +34,17 @@ struct host1x_syncpt_ops {
int (*patch_wait)(struct host1x_syncpt *syncpt, void *patch_addr);
};
struct host1x_intr_ops {
int (*init_host_sync)(struct host1x *host, u32 cpm,
void (*syncpt_thresh_work)(struct work_struct *work));
void (*set_syncpt_threshold)(
struct host1x *host, u32 id, u32 thresh);
void (*enable_syncpt_intr)(struct host1x *host, u32 id);
void (*disable_syncpt_intr)(struct host1x *host, u32 id);
void (*disable_all_syncpt_intrs)(struct host1x *host);
int (*free_syncpt_irq)(struct host1x *host);
};
struct host1x_info {
int nb_channels; /* host1x: num channels supported */
int nb_pts; /* host1x: num syncpoints supported */
@ -50,7 +62,13 @@ struct host1x {
struct device *dev;
struct clk *clk;
struct mutex intr_mutex;
struct workqueue_struct *intr_wq;
int intr_syncpt_irq;
const struct host1x_syncpt_ops *syncpt_op;
const struct host1x_intr_ops *intr_op;
};
void host1x_sync_writel(struct host1x *host1x, u32 r, u32 v);
@ -93,4 +111,37 @@ static inline int host1x_hw_syncpt_patch_wait(struct host1x *host,
return host->syncpt_op->patch_wait(sp, patch_addr);
}
static inline int host1x_hw_intr_init_host_sync(struct host1x *host, u32 cpm,
void (*syncpt_thresh_work)(struct work_struct *))
{
return host->intr_op->init_host_sync(host, cpm, syncpt_thresh_work);
}
static inline void host1x_hw_intr_set_syncpt_threshold(struct host1x *host,
u32 id, u32 thresh)
{
host->intr_op->set_syncpt_threshold(host, id, thresh);
}
static inline void host1x_hw_intr_enable_syncpt_intr(struct host1x *host,
u32 id)
{
host->intr_op->enable_syncpt_intr(host, id);
}
static inline void host1x_hw_intr_disable_syncpt_intr(struct host1x *host,
u32 id)
{
host->intr_op->disable_syncpt_intr(host, id);
}
static inline void host1x_hw_intr_disable_all_syncpt_intrs(struct host1x *host)
{
host->intr_op->disable_all_syncpt_intrs(host);
}
static inline int host1x_hw_intr_free_syncpt_irq(struct host1x *host)
{
return host->intr_op->free_syncpt_irq(host);
}
#endif

2
drivers/gpu/host1x/hw/host1x01.c
View File

@ -21,6 +21,7 @@
#include "hw/host1x01_hardware.h"
/* include code */
#include "hw/intr_hw.c"
#include "hw/syncpt_hw.c"
#include "dev.h"
@ -28,6 +29,7 @@
int host1x01_init(struct host1x *host)
{
host->syncpt_op = &host1x_syncpt_ops;
host->intr_op = &host1x_intr_ops;
return 0;
}

42
drivers/gpu/host1x/hw/hw_host1x01_sync.h
View File

@ -59,6 +59,48 @@ static inline u32 host1x_sync_syncpt_r(unsigned int id)
}
#define HOST1X_SYNC_SYNCPT(id) \
host1x_sync_syncpt_r(id)
static inline u32 host1x_sync_syncpt_thresh_cpu0_int_status_r(unsigned int id)
{
return 0x40 + id * REGISTER_STRIDE;
}
#define HOST1X_SYNC_SYNCPT_THRESH_CPU0_INT_STATUS(id) \
host1x_sync_syncpt_thresh_cpu0_int_status_r(id)
static inline u32 host1x_sync_syncpt_thresh_int_disable_r(unsigned int id)
{
return 0x60 + id * REGISTER_STRIDE;
}
#define HOST1X_SYNC_SYNCPT_THRESH_INT_DISABLE(id) \
host1x_sync_syncpt_thresh_int_disable_r(id)
static inline u32 host1x_sync_syncpt_thresh_int_enable_cpu0_r(unsigned int id)
{
return 0x68 + id * REGISTER_STRIDE;
}
#define HOST1X_SYNC_SYNCPT_THRESH_INT_ENABLE_CPU0(id) \
host1x_sync_syncpt_thresh_int_enable_cpu0_r(id)
static inline u32 host1x_sync_usec_clk_r(void)
{
return 0x1a4;
}
#define HOST1X_SYNC_USEC_CLK \
host1x_sync_usec_clk_r()
static inline u32 host1x_sync_ctxsw_timeout_cfg_r(void)
{
return 0x1a8;
}
#define HOST1X_SYNC_CTXSW_TIMEOUT_CFG \
host1x_sync_ctxsw_timeout_cfg_r()
static inline u32 host1x_sync_ip_busy_timeout_r(void)
{
return 0x1bc;
}
#define HOST1X_SYNC_IP_BUSY_TIMEOUT \
host1x_sync_ip_busy_timeout_r()
static inline u32 host1x_sync_syncpt_int_thresh_r(unsigned int id)
{
return 0x500 + id * REGISTER_STRIDE;
}
#define HOST1X_SYNC_SYNCPT_INT_THRESH(id) \
host1x_sync_syncpt_int_thresh_r(id)
static inline u32 host1x_sync_syncpt_base_r(unsigned int id)
{
return 0x600 + id * REGISTER_STRIDE;

143
drivers/gpu/host1x/hw/intr_hw.c Normal file
View File

@ -0,0 +1,143 @@
/*
* Tegra host1x Interrupt Management
*
* Copyright (C) 2010 Google, Inc.
* 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 <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <asm/mach/irq.h>
#include "intr.h"
#include "dev.h"
/*
* Sync point threshold interrupt service function
* Handles sync point threshold triggers, in interrupt context
*/
static void host1x_intr_syncpt_handle(struct host1x_syncpt *syncpt)
{
unsigned int id = syncpt->id;
struct host1x *host = syncpt->host;
host1x_sync_writel(host, BIT_MASK(id),
HOST1X_SYNC_SYNCPT_THRESH_INT_DISABLE(BIT_WORD(id)));
host1x_sync_writel(host, BIT_MASK(id),
HOST1X_SYNC_SYNCPT_THRESH_CPU0_INT_STATUS(BIT_WORD(id)));
queue_work(host->intr_wq, &syncpt->intr.work);
}
static irqreturn_t syncpt_thresh_isr(int irq, void *dev_id)
{
struct host1x *host = dev_id;
unsigned long reg;
int i, id;
for (i = 0; i <= BIT_WORD(host->info->nb_pts); i++) {
reg = host1x_sync_readl(host,
HOST1X_SYNC_SYNCPT_THRESH_CPU0_INT_STATUS(i));
for_each_set_bit(id, &reg, BITS_PER_LONG) {
struct host1x_syncpt *syncpt =
host->syncpt + (i * BITS_PER_LONG + id);
host1x_intr_syncpt_handle(syncpt);
}
}
return IRQ_HANDLED;
}
static void _host1x_intr_disable_all_syncpt_intrs(struct host1x *host)
{
u32 i;
for (i = 0; i <= BIT_WORD(host->info->nb_pts); ++i) {
host1x_sync_writel(host, 0xffffffffu,
HOST1X_SYNC_SYNCPT_THRESH_INT_DISABLE(i));
host1x_sync_writel(host, 0xffffffffu,
HOST1X_SYNC_SYNCPT_THRESH_CPU0_INT_STATUS(i));
}
}
static int _host1x_intr_init_host_sync(struct host1x *host, u32 cpm,
void (*syncpt_thresh_work)(struct work_struct *))
{
int i, err;
host1x_hw_intr_disable_all_syncpt_intrs(host);
for (i = 0; i < host->info->nb_pts; i++)
INIT_WORK(&host->syncpt[i].intr.work, syncpt_thresh_work);
err = devm_request_irq(host->dev, host->intr_syncpt_irq,
syncpt_thresh_isr, IRQF_SHARED,
"host1x_syncpt", host);
if (IS_ERR_VALUE(err)) {
WARN_ON(1);
return err;
}
/* disable the ip_busy_timeout. this prevents write drops */
host1x_sync_writel(host, 0, HOST1X_SYNC_IP_BUSY_TIMEOUT);
/*
* increase the auto-ack timout to the maximum value. 2d will hang
* otherwise on Tegra2.
*/
host1x_sync_writel(host, 0xff, HOST1X_SYNC_CTXSW_TIMEOUT_CFG);
/* update host clocks per usec */
host1x_sync_writel(host, cpm, HOST1X_SYNC_USEC_CLK);
return 0;
}
static void _host1x_intr_set_syncpt_threshold(struct host1x *host,
u32 id, u32 thresh)
{
host1x_sync_writel(host, thresh, HOST1X_SYNC_SYNCPT_INT_THRESH(id));
}
static void _host1x_intr_enable_syncpt_intr(struct host1x *host, u32 id)
{
host1x_sync_writel(host, BIT_MASK(id),
HOST1X_SYNC_SYNCPT_THRESH_INT_ENABLE_CPU0(BIT_WORD(id)));
}
static void _host1x_intr_disable_syncpt_intr(struct host1x *host, u32 id)
{
host1x_sync_writel(host, BIT_MASK(id),
HOST1X_SYNC_SYNCPT_THRESH_INT_DISABLE(BIT_WORD(id)));
host1x_sync_writel(host, BIT_MASK(id),
HOST1X_SYNC_SYNCPT_THRESH_CPU0_INT_STATUS(BIT_WORD(id)));
}
static int _host1x_free_syncpt_irq(struct host1x *host)
{
devm_free_irq(host->dev, host->intr_syncpt_irq, host);
flush_workqueue(host->intr_wq);
return 0;
}
static const struct host1x_intr_ops host1x_intr_ops = {
.init_host_sync = _host1x_intr_init_host_sync,
.set_syncpt_threshold = _host1x_intr_set_syncpt_threshold,
.enable_syncpt_intr = _host1x_intr_enable_syncpt_intr,
.disable_syncpt_intr = _host1x_intr_disable_syncpt_intr,
.disable_all_syncpt_intrs = _host1x_intr_disable_all_syncpt_intrs,
.free_syncpt_irq = _host1x_free_syncpt_irq,
};

328
drivers/gpu/host1x/intr.c Normal file
View File

@ -0,0 +1,328 @@
/*
* Tegra host1x Interrupt Management
*
* 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 <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/irq.h>
#include "dev.h"
#include "intr.h"
/* Wait list management */
enum waitlist_state {
WLS_PENDING,
WLS_REMOVED,
WLS_CANCELLED,
WLS_HANDLED
};
static void waiter_release(struct kref *kref)
{
kfree(container_of(kref, struct host1x_waitlist, refcount));
}
/*
* add a waiter to a waiter queue, sorted by threshold
* returns true if it was added at the head of the queue
*/
static bool add_waiter_to_queue(struct host1x_waitlist *waiter,
struct list_head *queue)
{
struct host1x_waitlist *pos;
u32 thresh = waiter->thresh;
list_for_each_entry_reverse(pos, queue, list)
if ((s32)(pos->thresh - thresh) <= 0) {
list_add(&waiter->list, &pos->list);
return false;
}
list_add(&waiter->list, queue);
return true;
}
/*
* run through a waiter queue for a single sync point ID
* and gather all completed waiters into lists by actions
*/
static void remove_completed_waiters(struct list_head *head, u32 sync,
struct list_head completed[HOST1X_INTR_ACTION_COUNT])
{
struct list_head *dest;
struct host1x_waitlist *waiter, *next;
list_for_each_entry_safe(waiter, next, head, list) {
if ((s32)(waiter->thresh - sync) > 0)
break;
dest = completed + waiter->action;
/* PENDING->REMOVED or CANCELLED->HANDLED */
if (atomic_inc_return(&waiter->state) == WLS_HANDLED || !dest) {
list_del(&waiter->list);
kref_put(&waiter->refcount, waiter_release);
} else
list_move_tail(&waiter->list, dest);
}
}
static void reset_threshold_interrupt(struct host1x *host,
struct list_head *head,
unsigned int id)
{
u32 thresh =
list_first_entry(head, struct host1x_waitlist, list)->thresh;
host1x_hw_intr_set_syncpt_threshold(host, id, thresh);
host1x_hw_intr_enable_syncpt_intr(host, id);
}
static void action_wakeup(struct host1x_waitlist *waiter)
{
wait_queue_head_t *wq = waiter->data;
wake_up(wq);
}
static void action_wakeup_interruptible(struct host1x_waitlist *waiter)
{
wait_queue_head_t *wq = waiter->data;
wake_up_interruptible(wq);
}
typedef void (*action_handler)(struct host1x_waitlist *waiter);
static action_handler action_handlers[HOST1X_INTR_ACTION_COUNT] = {
action_wakeup,
action_wakeup_interruptible,
};
static void run_handlers(struct list_head completed[HOST1X_INTR_ACTION_COUNT])
{
struct list_head *head = completed;
int i;
for (i = 0; i < HOST1X_INTR_ACTION_COUNT; ++i, ++head) {
action_handler handler = action_handlers[i];
struct host1x_waitlist *waiter, *next;
list_for_each_entry_safe(waiter, next, head, list) {
list_del(&waiter->list);
handler(waiter);
WARN_ON(atomic_xchg(&waiter->state, WLS_HANDLED) !=
WLS_REMOVED);
kref_put(&waiter->refcount, waiter_release);
}
}
}
/*
* Remove & handle all waiters that have completed for the given syncpt
*/
static int process_wait_list(struct host1x *host,
struct host1x_syncpt *syncpt,
u32 threshold)
{
struct list_head completed[HOST1X_INTR_ACTION_COUNT];
unsigned int i;
int empty;
for (i = 0; i < HOST1X_INTR_ACTION_COUNT; ++i)
INIT_LIST_HEAD(completed + i);
spin_lock(&syncpt->intr.lock);
remove_completed_waiters(&syncpt->intr.wait_head, threshold,
completed);
empty = list_empty(&syncpt->intr.wait_head);
if (empty)
host1x_hw_intr_disable_syncpt_intr(host, syncpt->id);
else
reset_threshold_interrupt(host, &syncpt->intr.wait_head,
syncpt->id);
spin_unlock(&syncpt->intr.lock);
run_handlers(completed);
return empty;
}
/*
* Sync point threshold interrupt service thread function
* Handles sync point threshold triggers, in thread context
*/
static void syncpt_thresh_work(struct work_struct *work)
{
struct host1x_syncpt_intr *syncpt_intr =
container_of(work, struct host1x_syncpt_intr, work);
struct host1x_syncpt *syncpt =
container_of(syncpt_intr, struct host1x_syncpt, intr);
unsigned int id = syncpt->id;
struct host1x *host = syncpt->host;
(void)process_wait_list(host, syncpt,
host1x_syncpt_load(host->syncpt + id));
}
int host1x_intr_add_action(struct host1x *host, u32 id, u32 thresh,
enum host1x_intr_action action, void *data,
struct host1x_waitlist *waiter, void **ref)
{
struct host1x_syncpt *syncpt;
int queue_was_empty;
if (waiter == NULL) {
pr_warn("%s: NULL waiter\n", __func__);
return -EINVAL;
}
/* initialize a new waiter */
INIT_LIST_HEAD(&waiter->list);
kref_init(&waiter->refcount);
if (ref)
kref_get(&waiter->refcount);
waiter->thresh = thresh;
waiter->action = action;
atomic_set(&waiter->state, WLS_PENDING);
waiter->data = data;
waiter->count = 1;
syncpt = host->syncpt + id;
spin_lock(&syncpt->intr.lock);
queue_was_empty = list_empty(&syncpt->intr.wait_head);
if (add_waiter_to_queue(waiter, &syncpt->intr.wait_head)) {
/* added at head of list - new threshold value */
host1x_hw_intr_set_syncpt_threshold(host, id, thresh);
/* added as first waiter - enable interrupt */
if (queue_was_empty)
host1x_hw_intr_enable_syncpt_intr(host, id);
}
spin_unlock(&syncpt->intr.lock);
if (ref)
*ref = waiter;
return 0;
}
void host1x_intr_put_ref(struct host1x *host, u32 id, void *ref)
{
struct host1x_waitlist *waiter = ref;
struct host1x_syncpt *syncpt;
while (atomic_cmpxchg(&waiter->state, WLS_PENDING, WLS_CANCELLED) ==
WLS_REMOVED)
schedule();
syncpt = host->syncpt + id;
(void)process_wait_list(host, syncpt,
host1x_syncpt_load(host->syncpt + id));
kref_put(&waiter->refcount, waiter_release);
}
int host1x_intr_init(struct host1x *host, unsigned int irq_sync)
{
unsigned int id;
u32 nb_pts = host1x_syncpt_nb_pts(host);
mutex_init(&host->intr_mutex);
host->intr_syncpt_irq = irq_sync;
host->intr_wq = create_workqueue("host_syncpt");
if (!host->intr_wq)
return -ENOMEM;
for (id = 0; id < nb_pts; ++id) {
struct host1x_syncpt *syncpt = host->syncpt + id;
spin_lock_init(&syncpt->intr.lock);
INIT_LIST_HEAD(&syncpt->intr.wait_head);
snprintf(syncpt->intr.thresh_irq_name,
sizeof(syncpt->intr.thresh_irq_name),
"host1x_sp_%02d", id);
}
host1x_intr_start(host);
return 0;
}
void host1x_intr_deinit(struct host1x *host)
{
host1x_intr_stop(host);
destroy_workqueue(host->intr_wq);
}
void host1x_intr_start(struct host1x *host)
{
u32 hz = clk_get_rate(host->clk);
int err;
mutex_lock(&host->intr_mutex);
err = host1x_hw_intr_init_host_sync(host, DIV_ROUND_UP(hz, 1000000),
syncpt_thresh_work);
if (err) {
mutex_unlock(&host->intr_mutex);
return;
}
mutex_unlock(&host->intr_mutex);
}
void host1x_intr_stop(struct host1x *host)
{
unsigned int id;
struct host1x_syncpt *syncpt = host->syncpt;
u32 nb_pts = host1x_syncpt_nb_pts(host);
mutex_lock(&host->intr_mutex);
host1x_hw_intr_disable_all_syncpt_intrs(host);
for (id = 0; id < nb_pts; ++id) {
struct host1x_waitlist *waiter, *next;
list_for_each_entry_safe(waiter, next,
&syncpt[id].intr.wait_head, list) {
if (atomic_cmpxchg(&waiter->state,
WLS_CANCELLED, WLS_HANDLED) == WLS_CANCELLED) {
list_del(&waiter->list);
kref_put(&waiter->refcount, waiter_release);
}
}
if (!list_empty(&syncpt[id].intr.wait_head)) {
/* output diagnostics */
mutex_unlock(&host->intr_mutex);
pr_warn("%s cannot stop syncpt intr id=%d\n",
__func__, id);
return;
}
}
host1x_hw_intr_free_syncpt_irq(host);
mutex_unlock(&host->intr_mutex);
}

96
drivers/gpu/host1x/intr.h Normal file
View File

@ -0,0 +1,96 @@
/*
* Tegra host1x Interrupt Management
*
* 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/>.
*/
#ifndef __HOST1X_INTR_H
#define __HOST1X_INTR_H
#include <linux/interrupt.h>
#include <linux/workqueue.h>
struct host1x;
enum host1x_intr_action {
/*
* Wake up a task.
* 'data' points to a wait_queue_head_t
*/
HOST1X_INTR_ACTION_WAKEUP,
/*
* Wake up a interruptible task.
* 'data' points to a wait_queue_head_t
*/
HOST1X_INTR_ACTION_WAKEUP_INTERRUPTIBLE,
HOST1X_INTR_ACTION_COUNT
};
struct host1x_syncpt_intr {
spinlock_t lock;
struct list_head wait_head;
char thresh_irq_name[12];
struct work_struct work;
};
struct host1x_waitlist {
struct list_head list;
struct kref refcount;
u32 thresh;
enum host1x_intr_action action;
atomic_t state;
void *data;
int count;
};
/*
* Schedule an action to be taken when a sync point reaches the given threshold.
*
* @id the sync point
* @thresh the threshold
* @action the action to take
* @data a pointer to extra data depending on action, see above
* @waiter waiter structure - assumes ownership
* @ref must be passed if cancellation is possible, else NULL
*
* This is a non-blocking api.
*/
int host1x_intr_add_action(struct host1x *host, u32 id, u32 thresh,
enum host1x_intr_action action, void *data,
struct host1x_waitlist *waiter, void **ref);
/*
* Unreference an action submitted to host1x_intr_add_action().
* You must call this if you passed non-NULL as ref.
* @ref the ref returned from host1x_intr_add_action()
*/
void host1x_intr_put_ref(struct host1x *host, u32 id, void *ref);
/* Initialize host1x sync point interrupt */
int host1x_intr_init(struct host1x *host, unsigned int irq_sync);
/* Deinitialize host1x sync point interrupt */
void host1x_intr_deinit(struct host1x *host);
/* Enable host1x sync point interrupt */
void host1x_intr_start(struct host1x *host);
/* Disable host1x sync point interrupt */
void host1x_intr_stop(struct host1x *host);
irqreturn_t host1x_syncpt_thresh_fn(void *dev_id);
#endif

159
drivers/gpu/host1x/syncpt.c
View File

@ -24,6 +24,10 @@
#include "syncpt.h"
#include "dev.h"
#include "intr.h"
#define SYNCPT_CHECK_PERIOD (2 * HZ)
#define MAX_STUCK_CHECK_COUNT 15
static struct host1x_syncpt *_host1x_syncpt_alloc(struct host1x *host,
struct device *dev,
@ -141,6 +145,161 @@ void host1x_syncpt_incr(struct host1x_syncpt *sp)
host1x_syncpt_cpu_incr(sp);
}
/*
* Updated sync point form hardware, and returns true if syncpoint is expired,
* false if we may need to wait
*/
static bool syncpt_load_min_is_expired(struct host1x_syncpt *sp, u32 thresh)
{
host1x_hw_syncpt_load(sp->host, sp);
return host1x_syncpt_is_expired(sp, thresh);
}
/*
* Main entrypoint for syncpoint value waits.
*/
int host1x_syncpt_wait(struct host1x_syncpt *sp, u32 thresh, long timeout,
u32 *value)
{
DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
void *ref;
struct host1x_waitlist *waiter;
int err = 0, check_count = 0;
u32 val;
if (value)
*value = 0;
/* first check cache */
if (host1x_syncpt_is_expired(sp, thresh)) {
if (value)
*value = host1x_syncpt_load(sp);
return 0;
}
/* try to read from register */
val = host1x_hw_syncpt_load(sp->host, sp);
if (host1x_syncpt_is_expired(sp, thresh)) {
if (value)
*value = val;
goto done;
}
if (!timeout) {
err = -EAGAIN;
goto done;
}
/* allocate a waiter */
waiter = kzalloc(sizeof(*waiter), GFP_KERNEL);
if (!waiter) {
err = -ENOMEM;
goto done;
}
/* schedule a wakeup when the syncpoint value is reached */
err = host1x_intr_add_action(sp->host, sp->id, thresh,
HOST1X_INTR_ACTION_WAKEUP_INTERRUPTIBLE,
&wq, waiter, &ref);
if (err)
goto done;
err = -EAGAIN;
/* Caller-specified timeout may be impractically low */
if (timeout < 0)
timeout = LONG_MAX;
/* wait for the syncpoint, or timeout, or signal */
while (timeout) {
long check = min_t(long, SYNCPT_CHECK_PERIOD, timeout);
int remain = wait_event_interruptible_timeout(wq,
syncpt_load_min_is_expired(sp, thresh),
check);
if (remain > 0 || host1x_syncpt_is_expired(sp, thresh)) {
if (value)
*value = host1x_syncpt_load(sp);
err = 0;
break;
}
if (remain < 0) {
err = remain;
break;
}
timeout -= check;
if (timeout && check_count <= MAX_STUCK_CHECK_COUNT) {
dev_warn(sp->host->dev,
"%s: syncpoint id %d (%s) stuck waiting %d, timeout=%ld\n",
current->comm, sp->id, sp->name,
thresh, timeout);
check_count++;
}
}
host1x_intr_put_ref(sp->host, sp->id, ref);
done:
return err;
}
EXPORT_SYMBOL(host1x_syncpt_wait);
/*
* Returns true if syncpoint is expired, false if we may need to wait
*/
bool host1x_syncpt_is_expired(struct host1x_syncpt *sp, u32 thresh)
{
u32 current_val;
u32 future_val;
smp_rmb();
current_val = (u32)atomic_read(&sp->min_val);
future_val = (u32)atomic_read(&sp->max_val);
/* Note the use of unsigned arithmetic here (mod 1<<32).
*
* c = current_val = min_val = the current value of the syncpoint.
* t = thresh = the value we are checking
* f = future_val = max_val = the value c will reach when all
* outstanding increments have completed.
*
* Note that c always chases f until it reaches f.
*
* Dtf = (f - t)
* Dtc = (c - t)
*
* Consider all cases:
*
* A) .....c..t..f..... Dtf < Dtc need to wait
* B) .....c.....f..t.. Dtf > Dtc expired
* C) ..t..c.....f..... Dtf > Dtc expired (Dct very large)
*
* Any case where f==c: always expired (for any t). Dtf == Dcf
* Any case where t==c: always expired (for any f). Dtf >= Dtc (because Dtc==0)
* Any case where t==f!=c: always wait. Dtf < Dtc (because Dtf==0,
* Dtc!=0)
*
* Other cases:
*
* A) .....t..f..c..... Dtf < Dtc need to wait
* A) .....f..c..t..... Dtf < Dtc need to wait
* A) .....f..t..c..... Dtf > Dtc expired
*
* So:
* Dtf >= Dtc implies EXPIRED (return true)
* Dtf < Dtc implies WAIT (return false)
*
* Note: If t is expired then we *cannot* wait on it. We would wait
* forever (hang the system).
*
* Note: do NOT get clever and remove the -thresh from both sides. It
* is NOT the same.
*
* If future valueis zero, we have a client managed sync point. In that
* case we do a direct comparison.
*/
if (!host1x_syncpt_client_managed(sp))
return future_val - thresh >= current_val - thresh;
else
return (s32)(current_val - thresh) >= 0;
}
int host1x_syncpt_init(struct host1x *host)
{
struct host1x_syncpt *syncpt;

12
drivers/gpu/host1x/syncpt.h
View File

@ -23,6 +23,8 @@
#include <linux/kernel.h>
#include <linux/sched.h>
#include "intr.h"
struct host1x;
struct host1x_syncpt {
@ -34,6 +36,9 @@ struct host1x_syncpt {
int client_managed;
struct host1x *host;
struct device *dev;
/* interrupt data */
struct host1x_syncpt_intr intr;
};
/* Initialize sync point array */
@ -113,6 +118,9 @@ void host1x_syncpt_cpu_incr(struct host1x_syncpt *sp);
/* Load current value from hardware to the shadow register. */
u32 host1x_syncpt_load(struct host1x_syncpt *sp);
/* Check if the given syncpoint value has already passed */
bool host1x_syncpt_is_expired(struct host1x_syncpt *sp, u32 thresh);
/* Save host1x sync point state into shadow registers. */
void host1x_syncpt_save(struct host1x *host);
@ -128,6 +136,10 @@ void host1x_syncpt_incr(struct host1x_syncpt *sp);
/* Indicate future operations by incrementing the sync point max. */
u32 host1x_syncpt_incr_max(struct host1x_syncpt *sp, u32 incrs);
/* Wait until sync point reaches a threshold value, or a timeout. */
int host1x_syncpt_wait(struct host1x_syncpt *sp, u32 thresh,
long timeout, u32 *value);
/* Check if sync point id is valid. */
static inline int host1x_syncpt_is_valid(struct host1x_syncpt *sp)
{