tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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 u32 min = host1x_syncpt_read_min(sp);
30 struct host1x *host = sp->host;
31
32 host1x_sync_writel(host, min, HOST1X_SYNC_SYNCPT(sp->id));
33}
34
35/*
36 * Write the current waitbase value back to hw.
37 */
38static void syncpt_restore_wait_base(struct host1x_syncpt *sp)
39{
40#if HOST1X_HW < 7
41 struct host1x *host = sp->host;
42
43 host1x_sync_writel(host, sp->base_val,
44 HOST1X_SYNC_SYNCPT_BASE(sp->id));
45#endif
46}
47
48/*
49 * Read waitbase value from hw.
50 */
51static void syncpt_read_wait_base(struct host1x_syncpt *sp)
52{
53#if HOST1X_HW < 7
54 struct host1x *host = sp->host;
55
56 sp->base_val =
57 host1x_sync_readl(host, HOST1X_SYNC_SYNCPT_BASE(sp->id));
58#endif
59}
60
61/*
62 * Updates the last value read from hardware.
63 */
64static u32 syncpt_load(struct host1x_syncpt *sp)
65{
66 struct host1x *host = sp->host;
67 u32 old, live;
68
69 /* Loop in case there's a race writing to min_val */
70 do {
71 old = host1x_syncpt_read_min(sp);
72 live = host1x_sync_readl(host, HOST1X_SYNC_SYNCPT(sp->id));
73 } while ((u32)atomic_cmpxchg(&sp->min_val, old, live) != old);
74
75 if (!host1x_syncpt_check_max(sp, live))
76 dev_err(host->dev, "%s failed: id=%u, min=%d, max=%d\n",
77 __func__, sp->id, host1x_syncpt_read_min(sp),
78 host1x_syncpt_read_max(sp));
79
80 return live;
81}
82
83/*
84 * Write a cpu syncpoint increment to the hardware, without touching
85 * the cache.
86 */
87static int syncpt_cpu_incr(struct host1x_syncpt *sp)
88{
89 struct host1x *host = sp->host;
90 u32 reg_offset = sp->id / 32;
91
92 if (!host1x_syncpt_client_managed(sp) &&
93 host1x_syncpt_idle(sp))
94 return -EINVAL;
95
96 host1x_sync_writel(host, BIT(sp->id % 32),
97 HOST1X_SYNC_SYNCPT_CPU_INCR(reg_offset));
98 wmb();
99
100 return 0;
101}
102
103/**
104 * syncpt_assign_to_channel() - Assign syncpoint to channel
105 * @sp: syncpoint
106 * @ch: channel
107 *
108 * On chips with the syncpoint protection feature (Tegra186+), assign @sp to
109 * @ch, preventing other channels from incrementing the syncpoints. If @ch is
110 * NULL, unassigns the syncpoint.
111 *
112 * On older chips, do nothing.
113 */
114static void syncpt_assign_to_channel(struct host1x_syncpt *sp,
115 struct host1x_channel *ch)
116{
117#if HOST1X_HW >= 6
118 struct host1x *host = sp->host;
119
120 if (!host->hv_regs)
121 return;
122
123 host1x_sync_writel(host,
124 HOST1X_SYNC_SYNCPT_CH_APP_CH(ch ? ch->id : 0xff),
125 HOST1X_SYNC_SYNCPT_CH_APP(sp->id));
126#endif
127}
128
129/**
130 * syncpt_enable_protection() - Enable syncpoint protection
131 * @host: host1x instance
132 *
133 * On chips with the syncpoint protection feature (Tegra186+), enable this
134 * feature. On older chips, do nothing.
135 */
136static void syncpt_enable_protection(struct host1x *host)
137{
138#if HOST1X_HW >= 6
139 if (!host->hv_regs)
140 return;
141
142 host1x_hypervisor_writel(host, HOST1X_HV_SYNCPT_PROT_EN_CH_EN,
143 HOST1X_HV_SYNCPT_PROT_EN);
144#endif
145}
146
147static const struct host1x_syncpt_ops host1x_syncpt_ops = {
148 .restore = syncpt_restore,
149 .restore_wait_base = syncpt_restore_wait_base,
150 .load_wait_base = syncpt_read_wait_base,
151 .load = syncpt_load,
152 .cpu_incr = syncpt_cpu_incr,
153 .assign_to_channel = syncpt_assign_to_channel,
154 .enable_protection = syncpt_enable_protection,
155};