diff options
Diffstat (limited to 'drivers/gpu/host1x/syncpt.c')
| -rw-r--r-- | drivers/gpu/host1x/syncpt.c | 580 |
1 files changed, 580 insertions, 0 deletions
diff --git a/drivers/gpu/host1x/syncpt.c b/drivers/gpu/host1x/syncpt.c new file mode 100644 index 000000000..f87a8705f --- /dev/null +++ b/drivers/gpu/host1x/syncpt.c @@ -0,0 +1,580 @@ +// 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; +} + +/** + * host1x_syncpt_alloc() - allocate a syncpoint + * @host: host1x device data + * @flags: bitfield of HOST1X_SYNCPT_* flags + * @name: name for the syncpoint for use in debug prints + * + * Allocates a hardware syncpoint for the caller's use. The caller then has + * the sole authority to mutate the syncpoint's value until it is freed again. + * + * If no free syncpoints are available, or a NULL name was specified, returns + * NULL. + */ +struct host1x_syncpt *host1x_syncpt_alloc(struct host1x *host, + unsigned long flags, + const char *name) +{ + struct host1x_syncpt *sp = host->syncpt; + char *full_name; + unsigned int i; + + if (!name) + return NULL; + + mutex_lock(&host->syncpt_mutex); + + for (i = 0; i < host->info->nb_pts && kref_read(&sp->ref); 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; + } + + full_name = kasprintf(GFP_KERNEL, "%u-%s", sp->id, name); + if (!full_name) + goto free_base; + + sp->name = full_name; + + if (flags & HOST1X_SYNCPT_CLIENT_MANAGED) + sp->client_managed = true; + else + sp->client_managed = false; + + kref_init(&sp->ref); + + 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; +} +EXPORT_SYMBOL(host1x_syncpt_alloc); + +/** + * 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++) { + /* + * 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, sp_base + i, NULL); + 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); + + host1x_hw_syncpt_enable_protection(host); + + 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; + + if (value) + *value = host1x_syncpt_load(sp); + + if (host1x_syncpt_is_expired(sp, thresh)) + return 0; + + 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, true); + +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; + + smp_rmb(); + + current_val = (u32)atomic_read(&sp->min_val); + + return ((current_val - thresh) & 0x80000000U) == 0U; +} + +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; + } + + for (i = 0; i < host->info->nb_bases; i++) + bases[i].id = i; + + mutex_init(&host->syncpt_mutex); + host->syncpt = syncpt; + host->bases = bases; + + /* Allocate sync point to use for clearing waits for expired fences */ + host->nop_sp = host1x_syncpt_alloc(host, 0, "reserved-nop"); + if (!host->nop_sp) + return -ENOMEM; + + if (host->info->reserve_vblank_syncpts) { + kref_init(&host->syncpt[26].ref); + kref_init(&host->syncpt[27].ref); + } + + 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_put(). + */ +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, flags, dev_name(client->dev)); +} +EXPORT_SYMBOL(host1x_syncpt_request); + +static void syncpt_release(struct kref *ref) +{ + struct host1x_syncpt *sp = container_of(ref, struct host1x_syncpt, ref); + + atomic_set(&sp->max_val, host1x_syncpt_read(sp)); + + sp->locked = false; + + mutex_lock(&sp->host->syncpt_mutex); + + host1x_syncpt_base_free(sp->base); + kfree(sp->name); + sp->base = NULL; + sp->name = NULL; + sp->client_managed = false; + + mutex_unlock(&sp->host->syncpt_mutex); +} + +/** + * host1x_syncpt_put() - 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. + */ +void host1x_syncpt_put(struct host1x_syncpt *sp) +{ + if (!sp) + return; + + kref_put(&sp->ref, syncpt_release); +} +EXPORT_SYMBOL(host1x_syncpt_put); + +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_by_id() - obtain a syncpoint by ID + * @host: host1x controller + * @id: syncpoint ID + */ +struct host1x_syncpt *host1x_syncpt_get_by_id(struct host1x *host, + unsigned int id) +{ + if (id >= host->info->nb_pts) + return NULL; + + if (kref_get_unless_zero(&host->syncpt[id].ref)) + return &host->syncpt[id]; + else + return NULL; +} +EXPORT_SYMBOL(host1x_syncpt_get_by_id); + +/** + * host1x_syncpt_get_by_id_noref() - obtain a syncpoint by ID but don't + * increase the refcount. + * @host: host1x controller + * @id: syncpoint ID + */ +struct host1x_syncpt *host1x_syncpt_get_by_id_noref(struct host1x *host, + unsigned int id) +{ + if (id >= host->info->nb_pts) + return NULL; + + return &host->syncpt[id]; +} +EXPORT_SYMBOL(host1x_syncpt_get_by_id_noref); + +/** + * host1x_syncpt_get() - increment syncpoint refcount + * @sp: syncpoint + */ +struct host1x_syncpt *host1x_syncpt_get(struct host1x_syncpt *sp) +{ + kref_get(&sp->ref); + + return sp; +} +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); + +static void do_nothing(struct kref *ref) +{ +} + +/** + * host1x_syncpt_release_vblank_reservation() - Make VBLANK syncpoint + * available for allocation + * + * @client: host1x bus client + * @syncpt_id: syncpoint ID to make available + * + * Makes VBLANK<i> syncpoint available for allocatation if it was + * reserved at initialization time. This should be called by the display + * driver after it has ensured that any VBLANK increment programming configured + * by the boot chain has been disabled. + */ +void host1x_syncpt_release_vblank_reservation(struct host1x_client *client, + u32 syncpt_id) +{ + struct host1x *host = dev_get_drvdata(client->host->parent); + + if (!host->info->reserve_vblank_syncpts) + return; + + kref_put(&host->syncpt[syncpt_id].ref, do_nothing); +} +EXPORT_SYMBOL(host1x_syncpt_release_vblank_reservation); |