[PATCHv7 03/10] gpu: host1x: Add syncpoint wait and interrupts
Terje Bergstrom
tbergstrom at nvidia.com
Wed Mar 13 05:36:19 PDT 2013
Add support for sync point interrupts, and sync point wait. Sync
point wait used interrupts for unblocking wait.
Signed-off-by: Arto Merilainen <amerilainen at nvidia.com>
Signed-off-by: Terje Bergstrom <tbergstrom at nvidia.com>
---
drivers/gpu/host1x/Makefile | 1 +
drivers/gpu/host1x/dev.c | 12 ++
drivers/gpu/host1x/dev.h | 51 +++++
drivers/gpu/host1x/hw/host1x01.c | 2 +
drivers/gpu/host1x/hw/hw_host1x01_sync.h | 42 ++++
drivers/gpu/host1x/hw/intr_hw.c | 143 +++++++++++++
drivers/gpu/host1x/intr.c | 328 ++++++++++++++++++++++++++++++
drivers/gpu/host1x/intr.h | 96 +++++++++
drivers/gpu/host1x/syncpt.c | 159 +++++++++++++++
drivers/gpu/host1x/syncpt.h | 14 +-
10 files changed, 847 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/host1x/hw/intr_hw.c
create mode 100644 drivers/gpu/host1x/intr.c
create mode 100644 drivers/gpu/host1x/intr.h
diff --git a/drivers/gpu/host1x/Makefile b/drivers/gpu/host1x/Makefile
index 363e6ab..5ef47ff 100644
--- a/drivers/gpu/host1x/Makefile
+++ b/drivers/gpu/host1x/Makefile
@@ -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
diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c
index d95a9b2..4421e28 100644
--- a/drivers/gpu/host1x/dev.c
+++ b/drivers/gpu/host1x/dev.c
@@ -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)
@@ -127,12 +128,23 @@ static int host1x_probe(struct platform_device *pdev)
return err;
}
+ err = host1x_intr_init(host, syncpt_irq);
+ if (err) {
+ dev_err(dev, "failed to init irq");
+ 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);
return 0;
diff --git a/drivers/gpu/host1x/dev.h b/drivers/gpu/host1x/dev.h
index 750daa3..fb5f842 100644
--- a/drivers/gpu/host1x/dev.h
+++ b/drivers/gpu/host1x/dev.h
@@ -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;
+
};
static inline struct host1x *host1x_get_host(struct device *dev)
@@ -101,4 +119,37 @@ 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
diff --git a/drivers/gpu/host1x/hw/host1x01.c b/drivers/gpu/host1x/hw/host1x01.c
index 612b457..f5c35fa 100644
--- a/drivers/gpu/host1x/hw/host1x01.c
+++ b/drivers/gpu/host1x/hw/host1x01.c
@@ -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;
}
diff --git a/drivers/gpu/host1x/hw/hw_host1x01_sync.h b/drivers/gpu/host1x/hw/hw_host1x01_sync.h
index 3af258b..eea0bb0 100644
--- a/drivers/gpu/host1x/hw/hw_host1x01_sync.h
+++ b/drivers/gpu/host1x/hw/hw_host1x01_sync.h
@@ -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;
diff --git a/drivers/gpu/host1x/hw/intr_hw.c b/drivers/gpu/host1x/hw/intr_hw.c
new file mode 100644
index 0000000..b592eef
--- /dev/null
+++ b/drivers/gpu/host1x/hw/intr_hw.c
@@ -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, ®, 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,
+};
diff --git a/drivers/gpu/host1x/intr.c b/drivers/gpu/host1x/intr.c
new file mode 100644
index 0000000..b1b5a80
--- /dev/null
+++ b/drivers/gpu/host1x/intr.c
@@ -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);
+}
diff --git a/drivers/gpu/host1x/intr.h b/drivers/gpu/host1x/intr.h
new file mode 100644
index 0000000..a3f06ab
--- /dev/null
+++ b/drivers/gpu/host1x/intr.h
@@ -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
diff --git a/drivers/gpu/host1x/syncpt.c b/drivers/gpu/host1x/syncpt.c
index 9df962c..a8613eb 100644
--- a/drivers/gpu/host1x/syncpt.c
+++ b/drivers/gpu/host1x/syncpt.c
@@ -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;
diff --git a/drivers/gpu/host1x/syncpt.h b/drivers/gpu/host1x/syncpt.h
index 119ccd5..17c1616 100644
--- a/drivers/gpu/host1x/syncpt.h
+++ b/drivers/gpu/host1x/syncpt.h
@@ -19,9 +19,11 @@
#ifndef __HOST1X_SYNCPT_H
#define __HOST1X_SYNCPT_H
+#include <linux/atomic.h>
#include <linux/kernel.h>
#include <linux/sched.h>
-#include <linux/atomic.h>
+
+#include "intr.h"
struct host1x;
@@ -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)
{
--
1.7.9.5
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