1/*
  2 * Tegra host1x Syncpoints
  3 *
  4 * Copyright (c) 2010-2013, NVIDIA Corporation.
  5 *
  6 * This program is free software; you can redistribute it and/or modify it
  7 * under the terms and conditions of the GNU General Public License,
  8 * version 2, as published by the Free Software Foundation.
  9 *
 10 * This program is distributed in the hope it will be useful, but WITHOUT
 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 13 * more details.
 14 *
 15 * You should have received a copy of the GNU General Public License
 16 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 17 */
 18
 19#include <linux/io.h>
 20
 21#include "../dev.h"
 22#include "../syncpt.h"
 23
 24/*
 25 * Write the current syncpoint value back to hw.
 26 */
 27static void syncpt_restore(struct host1x_syncpt *sp)
 28{
 29	struct host1x *host = sp->host;
 30	int min = host1x_syncpt_read_min(sp);
 31	host1x_sync_writel(host, min, HOST1X_SYNC_SYNCPT(sp->id));
 32}
 33
 34/*
 35 * Write the current waitbase value back to hw.
 36 */
 37static void syncpt_restore_wait_base(struct host1x_syncpt *sp)
 38{
 39	struct host1x *host = sp->host;
 40	host1x_sync_writel(host, sp->base_val,
 41			   HOST1X_SYNC_SYNCPT_BASE(sp->id));
 42}
 43
 44/*
 45 * Read waitbase value from hw.
 46 */
 47static void syncpt_read_wait_base(struct host1x_syncpt *sp)
 48{
 49	struct host1x *host = sp->host;
 50	sp->base_val =
 51		host1x_sync_readl(host, HOST1X_SYNC_SYNCPT_BASE(sp->id));
 52}
 53
 54/*
 55 * Updates the last value read from hardware.
 56 */
 57static u32 syncpt_load(struct host1x_syncpt *sp)
 58{
 59	struct host1x *host = sp->host;
 60	u32 old, live;
 61
 62	/* Loop in case there's a race writing to min_val */
 63	do {
 64		old = host1x_syncpt_read_min(sp);
 65		live = host1x_sync_readl(host, HOST1X_SYNC_SYNCPT(sp->id));
 66	} while ((u32)atomic_cmpxchg(&sp->min_val, old, live) != old);
 67
 68	if (!host1x_syncpt_check_max(sp, live))
 69		dev_err(host->dev, "%s failed: id=%u, min=%d, max=%d\n",
 70			__func__, sp->id, host1x_syncpt_read_min(sp),
 71			host1x_syncpt_read_max(sp));
 72
 73	return live;
 74}
 75
 76/*
 77 * Write a cpu syncpoint increment to the hardware, without touching
 78 * the cache.
 79 */
 80static int syncpt_cpu_incr(struct host1x_syncpt *sp)
 81{
 82	struct host1x *host = sp->host;
 83	u32 reg_offset = sp->id / 32;
 84
 85	if (!host1x_syncpt_client_managed(sp) &&
 86	    host1x_syncpt_idle(sp))
 87		return -EINVAL;
 88	host1x_sync_writel(host, BIT_MASK(sp->id),
 89			   HOST1X_SYNC_SYNCPT_CPU_INCR(reg_offset));
 90	wmb();
 91
 92	return 0;
 93}
 94
 95/* remove a wait pointed to by patch_addr */
 96static int syncpt_patch_wait(struct host1x_syncpt *sp, void *patch_addr)
 97{
 98	u32 override = host1x_class_host_wait_syncpt(
 99		HOST1X_SYNCPT_RESERVED, 0);
100
101	*((u32 *)patch_addr) = override;
102	return 0;
103}
104
105static const struct host1x_syncpt_ops host1x_syncpt_ops = {
106	.restore = syncpt_restore,
107	.restore_wait_base = syncpt_restore_wait_base,
108	.load_wait_base = syncpt_read_wait_base,
109	.load = syncpt_load,
110	.cpu_incr = syncpt_cpu_incr,
111	.patch_wait = syncpt_patch_wait,
112};