1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2021, NVIDIA Corporation.
*/
#include <linux/device.h>
#include <linux/kref.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pid.h>
#include <linux/slab.h>
#include "context.h"
#include "dev.h"
static void host1x_memory_context_release(struct device *dev)
{
/* context device is freed in host1x_memory_context_list_free() */
}
int host1x_memory_context_list_init(struct host1x *host1x)
{
struct host1x_memory_context_list *cdl = &host1x->context_list;
struct device_node *node = host1x->dev->of_node;
struct host1x_memory_context *ctx;
unsigned int i;
int err;
cdl->devs = NULL;
cdl->len = 0;
mutex_init(&cdl->lock);
err = of_property_count_u32_elems(node, "iommu-map");
if (err < 0)
return 0;
cdl->len = err / 4;
cdl->devs = kcalloc(cdl->len, sizeof(*cdl->devs), GFP_KERNEL);
if (!cdl->devs)
return -ENOMEM;
for (i = 0; i < cdl->len; i++) {
ctx = &cdl->devs[i];
ctx->host = host1x;
device_initialize(&ctx->dev);
/*
* Due to an issue with T194 NVENC, only 38 bits can be used.
* Anyway, 256GiB of IOVA ought to be enough for anyone.
*/
ctx->dma_mask = DMA_BIT_MASK(38);
ctx->dev.dma_mask = &ctx->dma_mask;
ctx->dev.coherent_dma_mask = ctx->dma_mask;
dev_set_name(&ctx->dev, "host1x-ctx.%d", i);
ctx->dev.bus = &host1x_context_device_bus_type;
ctx->dev.parent = host1x->dev;
ctx->dev.release = host1x_memory_context_release;
ctx->dev.dma_parms = &ctx->dma_parms;
dma_set_max_seg_size(&ctx->dev, UINT_MAX);
err = device_add(&ctx->dev);
if (err) {
dev_err(host1x->dev, "could not add context device %d: %d\n", i, err);
put_device(&ctx->dev);
goto unreg_devices;
}
err = of_dma_configure_id(&ctx->dev, node, true, &i);
if (err) {
dev_err(host1x->dev, "IOMMU configuration failed for context device %d: %d\n",
i, err);
device_unregister(&ctx->dev);
goto unreg_devices;
}
if (!tegra_dev_iommu_get_stream_id(&ctx->dev, &ctx->stream_id) ||
!device_iommu_mapped(&ctx->dev)) {
dev_err(host1x->dev, "Context device %d has no IOMMU!\n", i);
device_unregister(&ctx->dev);
/*
* This means that if IOMMU is disabled but context devices
* are defined in the device tree, Host1x will fail to probe.
* That's probably OK in this time and age.
*/
err = -EINVAL;
goto unreg_devices;
}
}
return 0;
unreg_devices:
while (i--)
device_unregister(&cdl->devs[i].dev);
kfree(cdl->devs);
cdl->devs = NULL;
cdl->len = 0;
return err;
}
void host1x_memory_context_list_free(struct host1x_memory_context_list *cdl)
{
unsigned int i;
for (i = 0; i < cdl->len; i++)
device_unregister(&cdl->devs[i].dev);
kfree(cdl->devs);
cdl->len = 0;
}
struct host1x_memory_context *host1x_memory_context_alloc(struct host1x *host1x,
struct device *dev,
struct pid *pid)
{
struct host1x_memory_context_list *cdl = &host1x->context_list;
struct host1x_memory_context *free = NULL;
int i;
if (!cdl->len)
return ERR_PTR(-EOPNOTSUPP);
mutex_lock(&cdl->lock);
for (i = 0; i < cdl->len; i++) {
struct host1x_memory_context *cd = &cdl->devs[i];
if (cd->dev.iommu->iommu_dev != dev->iommu->iommu_dev)
continue;
if (cd->owner == pid) {
refcount_inc(&cd->ref);
mutex_unlock(&cdl->lock);
return cd;
} else if (!cd->owner && !free) {
free = cd;
}
}
if (!free) {
mutex_unlock(&cdl->lock);
return ERR_PTR(-EBUSY);
}
refcount_set(&free->ref, 1);
free->owner = get_pid(pid);
mutex_unlock(&cdl->lock);
return free;
}
EXPORT_SYMBOL_GPL(host1x_memory_context_alloc);
void host1x_memory_context_get(struct host1x_memory_context *cd)
{
refcount_inc(&cd->ref);
}
EXPORT_SYMBOL_GPL(host1x_memory_context_get);
void host1x_memory_context_put(struct host1x_memory_context *cd)
{
struct host1x_memory_context_list *cdl = &cd->host->context_list;
if (refcount_dec_and_mutex_lock(&cd->ref, &cdl->lock)) {
put_pid(cd->owner);
cd->owner = NULL;
mutex_unlock(&cdl->lock);
}
}
EXPORT_SYMBOL_GPL(host1x_memory_context_put);
|