drivers/gpu/host1x/hw/syncpt_hw.c

Source file repositories/reference/linux-study-clean/drivers/gpu/host1x/hw/syncpt_hw.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/host1x/hw/syncpt_hw.c
Extension
.c
Size
3304 bytes
Lines
142
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Tegra host1x Syncpoints
 *
 * Copyright (c) 2010-2013, NVIDIA Corporation.
 */

#include <linux/io.h>

#include "../dev.h"
#include "../syncpt.h"

/*
 * Write the current syncpoint value back to hw.
 */
static void syncpt_restore(struct host1x_syncpt *sp)
{
	u32 min = host1x_syncpt_read_min(sp);
	struct host1x *host = sp->host;

	host1x_sync_writel(host, min, HOST1X_SYNC_SYNCPT(sp->id));
}

/*
 * Write the current waitbase value back to hw.
 */
static void syncpt_restore_wait_base(struct host1x_syncpt *sp)
{
#if HOST1X_HW < 7
	struct host1x *host = sp->host;

	host1x_sync_writel(host, sp->base_val,
			   HOST1X_SYNC_SYNCPT_BASE(sp->id));
#endif
}

/*
 * Read waitbase value from hw.
 */
static void syncpt_read_wait_base(struct host1x_syncpt *sp)
{
#if HOST1X_HW < 7
	struct host1x *host = sp->host;

	sp->base_val =
		host1x_sync_readl(host, HOST1X_SYNC_SYNCPT_BASE(sp->id));
#endif
}

/*
 * Updates the last value read from hardware.
 */
static u32 syncpt_load(struct host1x_syncpt *sp)
{
	struct host1x *host = sp->host;
	u32 old, live;

	/* Loop in case there's a race writing to min_val */
	do {
		old = host1x_syncpt_read_min(sp);
		live = host1x_sync_readl(host, HOST1X_SYNC_SYNCPT(sp->id));
	} while ((u32)atomic_cmpxchg(&sp->min_val, old, live) != old);

	if (!host1x_syncpt_check_max(sp, live))
		dev_err(host->dev, "%s failed: id=%u, min=%d, max=%d\n",
			__func__, sp->id, host1x_syncpt_read_min(sp),
			host1x_syncpt_read_max(sp));

	return live;
}

/*
 * Write a cpu syncpoint increment to the hardware, without touching
 * the cache.
 */
static int syncpt_cpu_incr(struct host1x_syncpt *sp)
{
	struct host1x *host = sp->host;
	u32 reg_offset = sp->id / 32;

	if (!host1x_syncpt_client_managed(sp) &&
	    host1x_syncpt_idle(sp))
		return -EINVAL;

	host1x_sync_writel(host, BIT(sp->id % 32),
			   HOST1X_SYNC_SYNCPT_CPU_INCR(reg_offset));
	wmb();

	return 0;
}

Annotation

Implementation Notes