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-rw-r--r--drivers/gpu/host1x/syncpt.c387
1 files changed, 387 insertions, 0 deletions
diff --git a/drivers/gpu/host1x/syncpt.c b/drivers/gpu/host1x/syncpt.c
new file mode 100644
index 00000000000..4b493453e80
--- /dev/null
+++ b/drivers/gpu/host1x/syncpt.c
@@ -0,0 +1,387 @@
+/*
+ * Tegra host1x Syncpoints
+ *
+ * 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/module.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+
+#include <trace/events/host1x.h>
+
+#include "syncpt.h"
+#include "dev.h"
+#include "intr.h"
+#include "debug.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,
+ int client_managed)
+{
+ int i;
+ struct host1x_syncpt *sp = host->syncpt;
+ char *name;
+
+ for (i = 0; i < host->info->nb_pts && sp->name; i++, sp++)
+ ;
+ if (sp->dev)
+ return NULL;
+
+ name = kasprintf(GFP_KERNEL, "%02d-%s", sp->id,
+ dev ? dev_name(dev) : NULL);
+ if (!name)
+ return NULL;
+
+ sp->dev = dev;
+ sp->name = name;
+ sp->client_managed = client_managed;
+
+ return sp;
+}
+
+u32 host1x_syncpt_id(struct host1x_syncpt *sp)
+{
+ return sp->id;
+}
+
+/*
+ * Updates the value sent to hardware.
+ */
+u32 host1x_syncpt_incr_max(struct host1x_syncpt *sp, u32 incrs)
+{
+ return (u32)atomic_add_return(incrs, &sp->max_val);
+}
+
+ /*
+ * Write cached syncpoint and waitbase values to hardware.
+ */
+void host1x_syncpt_restore(struct host1x *host)
+{
+ struct host1x_syncpt *sp_base = host->syncpt;
+ u32 i;
+
+ for (i = 0; i < host1x_syncpt_nb_pts(host); i++)
+ host1x_hw_syncpt_restore(host, sp_base + i);
+ for (i = 0; i < host1x_syncpt_nb_bases(host); i++)
+ host1x_hw_syncpt_restore_wait_base(host, sp_base + i);
+ wmb();
+}
+
+/*
+ * Update the cached syncpoint and waitbase values by reading them
+ * from the registers.
+ */
+void host1x_syncpt_save(struct host1x *host)
+{
+ struct host1x_syncpt *sp_base = host->syncpt;
+ u32 i;
+
+ for (i = 0; i < host1x_syncpt_nb_pts(host); i++) {
+ if (host1x_syncpt_client_managed(sp_base + i))
+ host1x_hw_syncpt_load(host, sp_base + i);
+ else
+ WARN_ON(!host1x_syncpt_idle(sp_base + i));
+ }
+
+ for (i = 0; i < host1x_syncpt_nb_bases(host); i++)
+ host1x_hw_syncpt_load_wait_base(host, sp_base + i);
+}
+
+/*
+ * Updates the cached syncpoint value by reading a new value from the hardware
+ * register
+ */
+u32 host1x_syncpt_load(struct host1x_syncpt *sp)
+{
+ u32 val;
+ val = host1x_hw_syncpt_load(sp->host, sp);
+ trace_host1x_syncpt_load_min(sp->id, val);
+
+ return val;
+}
+
+/*
+ * Get the current syncpoint base
+ */
+u32 host1x_syncpt_load_wait_base(struct host1x_syncpt *sp)
+{
+ u32 val;
+ host1x_hw_syncpt_load_wait_base(sp->host, sp);
+ val = sp->base_val;
+ return val;
+}
+
+/*
+ * Write a cpu syncpoint increment to the hardware, without touching
+ * the cache. Caller is responsible for host being powered.
+ */
+void host1x_syncpt_cpu_incr(struct host1x_syncpt *sp)
+{
+ host1x_hw_syncpt_cpu_incr(sp->host, sp);
+}
+
+/*
+ * Increment syncpoint value from cpu, updating cache
+ */
+void host1x_syncpt_incr(struct host1x_syncpt *sp)
+{
+ if (host1x_syncpt_client_managed(sp))
+ host1x_syncpt_incr_max(sp, 1);
+ 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);
+
+ host1x_debug_dump_syncpts(sp->host);
+ if (check_count == MAX_STUCK_CHECK_COUNT)
+ host1x_debug_dump(sp->host);
+ 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;
+}
+
+/* remove a wait pointed to by patch_addr */
+int host1x_syncpt_patch_wait(struct host1x_syncpt *sp, void *patch_addr)
+{
+ return host1x_hw_syncpt_patch_wait(sp->host, sp, patch_addr);
+}
+
+int host1x_syncpt_init(struct host1x *host)
+{
+ struct host1x_syncpt *syncpt;
+ int i;
+
+ syncpt = devm_kzalloc(host->dev, sizeof(*syncpt) * host->info->nb_pts,
+ GFP_KERNEL);
+ if (!syncpt)
+ return -ENOMEM;
+
+ for (i = 0; i < host->info->nb_pts; ++i) {
+ syncpt[i].id = i;
+ syncpt[i].host = host;
+ }
+
+ host->syncpt = syncpt;
+
+ host1x_syncpt_restore(host);
+
+ /* Allocate sync point to use for clearing waits for expired fences */
+ host->nop_sp = _host1x_syncpt_alloc(host, NULL, 0);
+ if (!host->nop_sp)
+ return -ENOMEM;
+
+ return 0;
+}
+
+struct host1x_syncpt *host1x_syncpt_request(struct device *dev,
+ int client_managed)
+{
+ struct host1x *host = dev_get_drvdata(dev->parent);
+ return _host1x_syncpt_alloc(host, dev, client_managed);
+}
+
+void host1x_syncpt_free(struct host1x_syncpt *sp)
+{
+ if (!sp)
+ return;
+
+ kfree(sp->name);
+ sp->dev = NULL;
+ sp->name = NULL;
+ sp->client_managed = 0;
+}
+
+void host1x_syncpt_deinit(struct host1x *host)
+{
+ int i;
+ struct host1x_syncpt *sp = host->syncpt;
+ for (i = 0; i < host->info->nb_pts; i++, sp++)
+ kfree(sp->name);
+}
+
+int host1x_syncpt_nb_pts(struct host1x *host)
+{
+ return host->info->nb_pts;
+}
+
+int host1x_syncpt_nb_bases(struct host1x *host)
+{
+ return host->info->nb_bases;
+}
+
+int host1x_syncpt_nb_mlocks(struct host1x *host)
+{
+ return host->info->nb_mlocks;
+}
+
+struct host1x_syncpt *host1x_syncpt_get(struct host1x *host, u32 id)
+{
+ if (host->info->nb_pts < id)
+ return NULL;
+ return host->syncpt + id;
+}