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 struct host1x *host = sp->host;
41
42 host1x_sync_writel(host, sp->base_val,
43 HOST1X_SYNC_SYNCPT_BASE(sp->id));
44}
45
46/*
47 * Read waitbase value from hw.
48 */
49static void syncpt_read_wait_base(struct host1x_syncpt *sp)
50{
51 struct host1x *host = sp->host;
52
53 sp->base_val =
54 host1x_sync_readl(host, HOST1X_SYNC_SYNCPT_BASE(sp->id));
55}
56
57/*
58 * Updates the last value read from hardware.
59 */
60static u32 syncpt_load(struct host1x_syncpt *sp)
61{
62 struct host1x *host = sp->host;
63 u32 old, live;
64
65 /* Loop in case there's a race writing to min_val */
66 do {
67 old = host1x_syncpt_read_min(sp);
68 live = host1x_sync_readl(host, HOST1X_SYNC_SYNCPT(sp->id));
69 } while ((u32)atomic_cmpxchg(&sp->min_val, old, live) != old);
70
71 if (!host1x_syncpt_check_max(sp, live))
72 dev_err(host->dev, "%s failed: id=%u, min=%d, max=%d\n",
73 __func__, sp->id, host1x_syncpt_read_min(sp),
74 host1x_syncpt_read_max(sp));
75
76 return live;
77}
78
79/*
80 * Write a cpu syncpoint increment to the hardware, without touching
81 * the cache.
82 */
83static int syncpt_cpu_incr(struct host1x_syncpt *sp)
84{
85 struct host1x *host = sp->host;
86 u32 reg_offset = sp->id / 32;
87
88 if (!host1x_syncpt_client_managed(sp) &&
89 host1x_syncpt_idle(sp))
90 return -EINVAL;
91
92 host1x_sync_writel(host, BIT(sp->id % 32),
93 HOST1X_SYNC_SYNCPT_CPU_INCR(reg_offset));
94 wmb();
95
96 return 0;
97}
98
99/* remove a wait pointed to by patch_addr */
100static int syncpt_patch_wait(struct host1x_syncpt *sp, void *patch_addr)
101{
102 u32 override = host1x_class_host_wait_syncpt(HOST1X_SYNCPT_RESERVED, 0);
103
104 *((u32 *)patch_addr) = override;
105
106 return 0;
107}
108
109/**
110 * syncpt_assign_to_channel() - Assign syncpoint to channel
111 * @sp: syncpoint
112 * @ch: channel
113 *
114 * On chips with the syncpoint protection feature (Tegra186+), assign @sp to
115 * @ch, preventing other channels from incrementing the syncpoints. If @ch is
116 * NULL, unassigns the syncpoint.
117 *
118 * On older chips, do nothing.
119 */
120static void syncpt_assign_to_channel(struct host1x_syncpt *sp,
121 struct host1x_channel *ch)
122{
123#if HOST1X_HW >= 6
124 struct host1x *host = sp->host;
125
126 if (!host->hv_regs)
127 return;
128
129 host1x_sync_writel(host,
130 HOST1X_SYNC_SYNCPT_CH_APP_CH(ch ? ch->id : 0xff),
131 HOST1X_SYNC_SYNCPT_CH_APP(sp->id));
132#endif
133}
134
135/**
136 * syncpt_enable_protection() - Enable syncpoint protection
137 * @host: host1x instance
138 *
139 * On chips with the syncpoint protection feature (Tegra186+), enable this
140 * feature. On older chips, do nothing.
141 */
142static void syncpt_enable_protection(struct host1x *host)
143{
144#if HOST1X_HW >= 6
145 if (!host->hv_regs)
146 return;
147
148 host1x_hypervisor_writel(host, HOST1X_HV_SYNCPT_PROT_EN_CH_EN,
149 HOST1X_HV_SYNCPT_PROT_EN);
150#endif
151}
152
153static const struct host1x_syncpt_ops host1x_syncpt_ops = {
154 .restore = syncpt_restore,
155 .restore_wait_base = syncpt_restore_wait_base,
156 .load_wait_base = syncpt_read_wait_base,
157 .load = syncpt_load,
158 .cpu_incr = syncpt_cpu_incr,
159 .patch_wait = syncpt_patch_wait,
160 .assign_to_channel = syncpt_assign_to_channel,
161 .enable_protection = syncpt_enable_protection,
162};