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 --- 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) {