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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/gpu/host1x/syncpt.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/host1x/syncpt.c')
-rw-r--r--drivers/gpu/host1x/syncpt.c554
1 files changed, 554 insertions, 0 deletions
diff --git a/drivers/gpu/host1x/syncpt.c b/drivers/gpu/host1x/syncpt.c
new file mode 100644
index 000000000..fce7892d5
--- /dev/null
+++ b/drivers/gpu/host1x/syncpt.c
@@ -0,0 +1,554 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Tegra host1x Syncpoints
+ *
+ * Copyright (c) 2010-2015, NVIDIA Corporation.
+ */
+
+#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_base *
+host1x_syncpt_base_request(struct host1x *host)
+{
+ struct host1x_syncpt_base *bases = host->bases;
+ unsigned int i;
+
+ for (i = 0; i < host->info->nb_bases; i++)
+ if (!bases[i].requested)
+ break;
+
+ if (i >= host->info->nb_bases)
+ return NULL;
+
+ bases[i].requested = true;
+ return &bases[i];
+}
+
+static void host1x_syncpt_base_free(struct host1x_syncpt_base *base)
+{
+ if (base)
+ base->requested = false;
+}
+
+static struct host1x_syncpt *host1x_syncpt_alloc(struct host1x *host,
+ struct host1x_client *client,
+ unsigned long flags)
+{
+ struct host1x_syncpt *sp = host->syncpt;
+ unsigned int i;
+ char *name;
+
+ mutex_lock(&host->syncpt_mutex);
+
+ for (i = 0; i < host->info->nb_pts && sp->name; i++, sp++)
+ ;
+
+ if (i >= host->info->nb_pts)
+ goto unlock;
+
+ if (flags & HOST1X_SYNCPT_HAS_BASE) {
+ sp->base = host1x_syncpt_base_request(host);
+ if (!sp->base)
+ goto unlock;
+ }
+
+ name = kasprintf(GFP_KERNEL, "%02u-%s", sp->id,
+ client ? dev_name(client->dev) : NULL);
+ if (!name)
+ goto free_base;
+
+ sp->client = client;
+ sp->name = name;
+
+ if (flags & HOST1X_SYNCPT_CLIENT_MANAGED)
+ sp->client_managed = true;
+ else
+ sp->client_managed = false;
+
+ mutex_unlock(&host->syncpt_mutex);
+ return sp;
+
+free_base:
+ host1x_syncpt_base_free(sp->base);
+ sp->base = NULL;
+unlock:
+ mutex_unlock(&host->syncpt_mutex);
+ return NULL;
+}
+
+/**
+ * host1x_syncpt_id() - retrieve syncpoint ID
+ * @sp: host1x syncpoint
+ *
+ * Given a pointer to a struct host1x_syncpt, retrieves its ID. This ID is
+ * often used as a value to program into registers that control how hardware
+ * blocks interact with syncpoints.
+ */
+u32 host1x_syncpt_id(struct host1x_syncpt *sp)
+{
+ return sp->id;
+}
+EXPORT_SYMBOL(host1x_syncpt_id);
+
+/**
+ * host1x_syncpt_incr_max() - update the value sent to hardware
+ * @sp: host1x syncpoint
+ * @incrs: number of increments
+ */
+u32 host1x_syncpt_incr_max(struct host1x_syncpt *sp, u32 incrs)
+{
+ return (u32)atomic_add_return(incrs, &sp->max_val);
+}
+EXPORT_SYMBOL(host1x_syncpt_incr_max);
+
+ /*
+ * Write cached syncpoint and waitbase values to hardware.
+ */
+void host1x_syncpt_restore(struct host1x *host)
+{
+ struct host1x_syncpt *sp_base = host->syncpt;
+ unsigned int 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;
+ unsigned int 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)
+{
+ host1x_hw_syncpt_load_wait_base(sp->host, sp);
+
+ return sp->base_val;
+}
+
+/**
+ * host1x_syncpt_incr() - increment syncpoint value from CPU, updating cache
+ * @sp: host1x syncpoint
+ */
+int host1x_syncpt_incr(struct host1x_syncpt *sp)
+{
+ return host1x_hw_syncpt_cpu_incr(sp->host, sp);
+}
+EXPORT_SYMBOL(host1x_syncpt_incr);
+
+/*
+ * 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);
+}
+
+/**
+ * host1x_syncpt_wait() - wait for a syncpoint to reach a given value
+ * @sp: host1x syncpoint
+ * @thresh: threshold
+ * @timeout: maximum time to wait for the syncpoint to reach the given value
+ * @value: return location for the syncpoint value
+ */
+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, 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;
+
+ 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 %u (%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;
+}
+
+int host1x_syncpt_init(struct host1x *host)
+{
+ struct host1x_syncpt_base *bases;
+ struct host1x_syncpt *syncpt;
+ unsigned int i;
+
+ syncpt = devm_kcalloc(host->dev, host->info->nb_pts, sizeof(*syncpt),
+ GFP_KERNEL);
+ if (!syncpt)
+ return -ENOMEM;
+
+ bases = devm_kcalloc(host->dev, host->info->nb_bases, sizeof(*bases),
+ GFP_KERNEL);
+ if (!bases)
+ return -ENOMEM;
+
+ for (i = 0; i < host->info->nb_pts; i++) {
+ syncpt[i].id = i;
+ syncpt[i].host = host;
+
+ /*
+ * Unassign syncpt from channels for purposes of Tegra186
+ * syncpoint protection. This prevents any channel from
+ * accessing it until it is reassigned.
+ */
+ host1x_hw_syncpt_assign_to_channel(host, &syncpt[i], NULL);
+ }
+
+ for (i = 0; i < host->info->nb_bases; i++)
+ bases[i].id = i;
+
+ mutex_init(&host->syncpt_mutex);
+ host->syncpt = syncpt;
+ host->bases = bases;
+
+ host1x_syncpt_restore(host);
+ host1x_hw_syncpt_enable_protection(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;
+}
+
+/**
+ * host1x_syncpt_request() - request a syncpoint
+ * @client: client requesting the syncpoint
+ * @flags: flags
+ *
+ * host1x client drivers can use this function to allocate a syncpoint for
+ * subsequent use. A syncpoint returned by this function will be reserved for
+ * use by the client exclusively. When no longer using a syncpoint, a host1x
+ * client driver needs to release it using host1x_syncpt_free().
+ */
+struct host1x_syncpt *host1x_syncpt_request(struct host1x_client *client,
+ unsigned long flags)
+{
+ struct host1x *host = dev_get_drvdata(client->host->parent);
+
+ return host1x_syncpt_alloc(host, client, flags);
+}
+EXPORT_SYMBOL(host1x_syncpt_request);
+
+/**
+ * host1x_syncpt_free() - free a requested syncpoint
+ * @sp: host1x syncpoint
+ *
+ * Release a syncpoint previously allocated using host1x_syncpt_request(). A
+ * host1x client driver should call this when the syncpoint is no longer in
+ * use. Note that client drivers must ensure that the syncpoint doesn't remain
+ * under the control of hardware after calling this function, otherwise two
+ * clients may end up trying to access the same syncpoint concurrently.
+ */
+void host1x_syncpt_free(struct host1x_syncpt *sp)
+{
+ if (!sp)
+ return;
+
+ mutex_lock(&sp->host->syncpt_mutex);
+
+ host1x_syncpt_base_free(sp->base);
+ kfree(sp->name);
+ sp->base = NULL;
+ sp->client = NULL;
+ sp->name = NULL;
+ sp->client_managed = false;
+
+ mutex_unlock(&sp->host->syncpt_mutex);
+}
+EXPORT_SYMBOL(host1x_syncpt_free);
+
+void host1x_syncpt_deinit(struct host1x *host)
+{
+ struct host1x_syncpt *sp = host->syncpt;
+ unsigned int i;
+
+ for (i = 0; i < host->info->nb_pts; i++, sp++)
+ kfree(sp->name);
+}
+
+/**
+ * host1x_syncpt_read_max() - read maximum syncpoint value
+ * @sp: host1x syncpoint
+ *
+ * The maximum syncpoint value indicates how many operations there are in
+ * queue, either in channel or in a software thread.
+ */
+u32 host1x_syncpt_read_max(struct host1x_syncpt *sp)
+{
+ smp_rmb();
+
+ return (u32)atomic_read(&sp->max_val);
+}
+EXPORT_SYMBOL(host1x_syncpt_read_max);
+
+/**
+ * host1x_syncpt_read_min() - read minimum syncpoint value
+ * @sp: host1x syncpoint
+ *
+ * The minimum syncpoint value is a shadow of the current sync point value in
+ * hardware.
+ */
+u32 host1x_syncpt_read_min(struct host1x_syncpt *sp)
+{
+ smp_rmb();
+
+ return (u32)atomic_read(&sp->min_val);
+}
+EXPORT_SYMBOL(host1x_syncpt_read_min);
+
+/**
+ * host1x_syncpt_read() - read the current syncpoint value
+ * @sp: host1x syncpoint
+ */
+u32 host1x_syncpt_read(struct host1x_syncpt *sp)
+{
+ return host1x_syncpt_load(sp);
+}
+EXPORT_SYMBOL(host1x_syncpt_read);
+
+unsigned int host1x_syncpt_nb_pts(struct host1x *host)
+{
+ return host->info->nb_pts;
+}
+
+unsigned int host1x_syncpt_nb_bases(struct host1x *host)
+{
+ return host->info->nb_bases;
+}
+
+unsigned int host1x_syncpt_nb_mlocks(struct host1x *host)
+{
+ return host->info->nb_mlocks;
+}
+
+/**
+ * host1x_syncpt_get() - obtain a syncpoint by ID
+ * @host: host1x controller
+ * @id: syncpoint ID
+ */
+struct host1x_syncpt *host1x_syncpt_get(struct host1x *host, unsigned int id)
+{
+ if (id >= host->info->nb_pts)
+ return NULL;
+
+ return host->syncpt + id;
+}
+EXPORT_SYMBOL(host1x_syncpt_get);
+
+/**
+ * host1x_syncpt_get_base() - obtain the wait base associated with a syncpoint
+ * @sp: host1x syncpoint
+ */
+struct host1x_syncpt_base *host1x_syncpt_get_base(struct host1x_syncpt *sp)
+{
+ return sp ? sp->base : NULL;
+}
+EXPORT_SYMBOL(host1x_syncpt_get_base);
+
+/**
+ * host1x_syncpt_base_id() - retrieve the ID of a syncpoint wait base
+ * @base: host1x syncpoint wait base
+ */
+u32 host1x_syncpt_base_id(struct host1x_syncpt_base *base)
+{
+ return base->id;
+}
+EXPORT_SYMBOL(host1x_syncpt_base_id);