Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/* Copyright 2024-2025 Tomeu Vizoso <tomeu@tomeuvizoso.net> */
3
4#include <drm/drm_device.h>
5#include <drm/drm_print.h>
6#include <drm/drm_utils.h>
7#include <drm/rocket_accel.h>
8#include <linux/dma-mapping.h>
9#include <linux/iommu.h>
10
11#include "rocket_drv.h"
12#include "rocket_gem.h"
13
14static void rocket_gem_bo_free(struct drm_gem_object *obj)
15{
16 struct rocket_gem_object *bo = to_rocket_bo(obj);
17 struct rocket_file_priv *rocket_priv = bo->driver_priv;
18 size_t unmapped;
19
20 drm_WARN_ON(obj->dev, refcount_read(&bo->base.pages_use_count) > 1);
21
22 unmapped = iommu_unmap(bo->domain->domain, bo->mm.start, bo->size);
23 drm_WARN_ON(obj->dev, unmapped != bo->size);
24
25 mutex_lock(&rocket_priv->mm_lock);
26 drm_mm_remove_node(&bo->mm);
27 mutex_unlock(&rocket_priv->mm_lock);
28
29 rocket_iommu_domain_put(bo->domain);
30 bo->domain = NULL;
31
32 drm_gem_shmem_free(&bo->base);
33}
34
35static const struct drm_gem_object_funcs rocket_gem_funcs = {
36 .free = rocket_gem_bo_free,
37 .print_info = drm_gem_shmem_object_print_info,
38 .pin = drm_gem_shmem_object_pin,
39 .unpin = drm_gem_shmem_object_unpin,
40 .get_sg_table = drm_gem_shmem_object_get_sg_table,
41 .vmap = drm_gem_shmem_object_vmap,
42 .vunmap = drm_gem_shmem_object_vunmap,
43 .mmap = drm_gem_shmem_object_mmap,
44 .vm_ops = &drm_gem_shmem_vm_ops,
45};
46
47struct drm_gem_object *rocket_gem_create_object(struct drm_device *dev, size_t size)
48{
49 struct rocket_gem_object *obj;
50
51 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
52 if (!obj)
53 return ERR_PTR(-ENOMEM);
54
55 obj->base.base.funcs = &rocket_gem_funcs;
56
57 return &obj->base.base;
58}
59
60int rocket_ioctl_create_bo(struct drm_device *dev, void *data, struct drm_file *file)
61{
62 struct rocket_file_priv *rocket_priv = file->driver_priv;
63 struct drm_rocket_create_bo *args = data;
64 struct drm_gem_shmem_object *shmem_obj;
65 struct rocket_gem_object *rkt_obj;
66 struct drm_gem_object *gem_obj;
67 struct sg_table *sgt;
68 int ret;
69
70 shmem_obj = drm_gem_shmem_create(dev, args->size);
71 if (IS_ERR(shmem_obj))
72 return PTR_ERR(shmem_obj);
73
74 gem_obj = &shmem_obj->base;
75 rkt_obj = to_rocket_bo(gem_obj);
76
77 rkt_obj->driver_priv = rocket_priv;
78 rkt_obj->domain = rocket_iommu_domain_get(rocket_priv);
79 rkt_obj->size = args->size;
80 rkt_obj->offset = 0;
81
82 ret = drm_gem_handle_create(file, gem_obj, &args->handle);
83 drm_gem_object_put(gem_obj);
84 if (ret)
85 goto err;
86
87 sgt = drm_gem_shmem_get_pages_sgt(shmem_obj);
88 if (IS_ERR(sgt)) {
89 ret = PTR_ERR(sgt);
90 goto err;
91 }
92
93 mutex_lock(&rocket_priv->mm_lock);
94 ret = drm_mm_insert_node_generic(&rocket_priv->mm, &rkt_obj->mm,
95 rkt_obj->size, PAGE_SIZE,
96 0, 0);
97 mutex_unlock(&rocket_priv->mm_lock);
98
99 ret = iommu_map_sgtable(rocket_priv->domain->domain,
100 rkt_obj->mm.start,
101 shmem_obj->sgt,
102 IOMMU_READ | IOMMU_WRITE);
103 if (ret < 0 || ret < args->size) {
104 drm_err(dev, "failed to map buffer: size=%d request_size=%u\n",
105 ret, args->size);
106 ret = -ENOMEM;
107 goto err_remove_node;
108 }
109
110 /* iommu_map_sgtable might have aligned the size */
111 rkt_obj->size = ret;
112 args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
113 args->dma_address = rkt_obj->mm.start;
114
115 return 0;
116
117err_remove_node:
118 mutex_lock(&rocket_priv->mm_lock);
119 drm_mm_remove_node(&rkt_obj->mm);
120 mutex_unlock(&rocket_priv->mm_lock);
121
122err:
123 drm_gem_shmem_object_free(gem_obj);
124
125 return ret;
126}
127
128int rocket_ioctl_prep_bo(struct drm_device *dev, void *data, struct drm_file *file)
129{
130 struct drm_rocket_prep_bo *args = data;
131 unsigned long timeout = drm_timeout_abs_to_jiffies(args->timeout_ns);
132 struct drm_gem_object *gem_obj;
133 struct drm_gem_shmem_object *shmem_obj;
134 long ret = 0;
135
136 if (args->reserved != 0) {
137 drm_dbg(dev, "Reserved field in drm_rocket_prep_bo struct should be 0.\n");
138 return -EINVAL;
139 }
140
141 gem_obj = drm_gem_object_lookup(file, args->handle);
142 if (!gem_obj)
143 return -ENOENT;
144
145 ret = dma_resv_wait_timeout(gem_obj->resv, DMA_RESV_USAGE_WRITE, true, timeout);
146 if (!ret)
147 ret = timeout ? -ETIMEDOUT : -EBUSY;
148
149 shmem_obj = &to_rocket_bo(gem_obj)->base;
150
151 dma_sync_sgtable_for_cpu(dev->dev, shmem_obj->sgt, DMA_BIDIRECTIONAL);
152
153 drm_gem_object_put(gem_obj);
154
155 return ret;
156}
157
158int rocket_ioctl_fini_bo(struct drm_device *dev, void *data, struct drm_file *file)
159{
160 struct drm_rocket_fini_bo *args = data;
161 struct drm_gem_shmem_object *shmem_obj;
162 struct rocket_gem_object *rkt_obj;
163 struct drm_gem_object *gem_obj;
164
165 if (args->reserved != 0) {
166 drm_dbg(dev, "Reserved field in drm_rocket_fini_bo struct should be 0.\n");
167 return -EINVAL;
168 }
169
170 gem_obj = drm_gem_object_lookup(file, args->handle);
171 if (!gem_obj)
172 return -ENOENT;
173
174 rkt_obj = to_rocket_bo(gem_obj);
175 shmem_obj = &rkt_obj->base;
176
177 dma_sync_sgtable_for_device(dev->dev, shmem_obj->sgt, DMA_BIDIRECTIONAL);
178
179 drm_gem_object_put(gem_obj);
180
181 return 0;
182}