xref: /linux/drivers/gpu/drm/etnaviv/etnaviv_iommu_v2.c (revision 2993c9b04e616df0848b655d7202a707a70fc876)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2016-2018 Etnaviv Project
4  */
5 
6 #include <linux/bitops.h>
7 #include <linux/dma-mapping.h>
8 #include <linux/platform_device.h>
9 #include <linux/sizes.h>
10 #include <linux/slab.h>
11 #include <linux/vmalloc.h>
12 
13 #include "etnaviv_cmdbuf.h"
14 #include "etnaviv_gpu.h"
15 #include "etnaviv_mmu.h"
16 #include "state.xml.h"
17 #include "state_hi.xml.h"
18 
19 #define MMUv2_PTE_PRESENT		BIT(0)
20 #define MMUv2_PTE_EXCEPTION		BIT(1)
21 #define MMUv2_PTE_WRITEABLE		BIT(2)
22 
23 #define MMUv2_MTLB_MASK			0xffc00000
24 #define MMUv2_MTLB_SHIFT		22
25 #define MMUv2_STLB_MASK			0x003ff000
26 #define MMUv2_STLB_SHIFT		12
27 
28 #define MMUv2_MAX_STLB_ENTRIES		1024
29 
30 struct etnaviv_iommuv2_context {
31 	struct etnaviv_iommu_context base;
32 	unsigned short id;
33 	/* M(aster) TLB aka first level pagetable */
34 	u32 *mtlb_cpu;
35 	dma_addr_t mtlb_dma;
36 	/* S(lave) TLB aka second level pagetable */
37 	u32 *stlb_cpu[MMUv2_MAX_STLB_ENTRIES];
38 	dma_addr_t stlb_dma[MMUv2_MAX_STLB_ENTRIES];
39 };
40 
41 static struct etnaviv_iommuv2_context *
42 to_v2_context(struct etnaviv_iommu_context *context)
43 {
44 	return container_of(context, struct etnaviv_iommuv2_context, base);
45 }
46 
47 static void etnaviv_iommuv2_free(struct etnaviv_iommu_context *context)
48 {
49 	struct etnaviv_iommuv2_context *v2_context = to_v2_context(context);
50 	int i;
51 
52 	drm_mm_takedown(&context->mm);
53 
54 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++) {
55 		if (v2_context->stlb_cpu[i])
56 			dma_free_wc(context->global->dev, SZ_4K,
57 				    v2_context->stlb_cpu[i],
58 				    v2_context->stlb_dma[i]);
59 	}
60 
61 	dma_free_wc(context->global->dev, SZ_4K, v2_context->mtlb_cpu,
62 		    v2_context->mtlb_dma);
63 
64 	clear_bit(v2_context->id, context->global->v2.pta_alloc);
65 
66 	vfree(v2_context);
67 }
68 static int
69 etnaviv_iommuv2_ensure_stlb(struct etnaviv_iommuv2_context *v2_context,
70 			    int stlb)
71 {
72 	if (v2_context->stlb_cpu[stlb])
73 		return 0;
74 
75 	v2_context->stlb_cpu[stlb] =
76 			dma_alloc_wc(v2_context->base.global->dev, SZ_4K,
77 				     &v2_context->stlb_dma[stlb],
78 				     GFP_KERNEL);
79 
80 	if (!v2_context->stlb_cpu[stlb])
81 		return -ENOMEM;
82 
83 	memset32(v2_context->stlb_cpu[stlb], MMUv2_PTE_EXCEPTION,
84 		 SZ_4K / sizeof(u32));
85 
86 	v2_context->mtlb_cpu[stlb] =
87 			v2_context->stlb_dma[stlb] | MMUv2_PTE_PRESENT;
88 
89 	return 0;
90 }
91 
92 static int etnaviv_iommuv2_map(struct etnaviv_iommu_context *context,
93 			       unsigned long iova, phys_addr_t paddr,
94 			       size_t size, int prot)
95 {
96 	struct etnaviv_iommuv2_context *v2_context = to_v2_context(context);
97 	int mtlb_entry, stlb_entry, ret;
98 	u32 entry = lower_32_bits(paddr) | MMUv2_PTE_PRESENT;
99 
100 	if (size != SZ_4K)
101 		return -EINVAL;
102 
103 	if (IS_ENABLED(CONFIG_PHYS_ADDR_T_64BIT))
104 		entry |= (upper_32_bits(paddr) & 0xff) << 4;
105 
106 	if (prot & ETNAVIV_PROT_WRITE)
107 		entry |= MMUv2_PTE_WRITEABLE;
108 
109 	mtlb_entry = (iova & MMUv2_MTLB_MASK) >> MMUv2_MTLB_SHIFT;
110 	stlb_entry = (iova & MMUv2_STLB_MASK) >> MMUv2_STLB_SHIFT;
111 
112 	ret = etnaviv_iommuv2_ensure_stlb(v2_context, mtlb_entry);
113 	if (ret)
114 		return ret;
115 
116 	v2_context->stlb_cpu[mtlb_entry][stlb_entry] = entry;
117 
118 	return 0;
119 }
120 
121 static size_t etnaviv_iommuv2_unmap(struct etnaviv_iommu_context *context,
122 				    unsigned long iova, size_t size)
123 {
124 	struct etnaviv_iommuv2_context *etnaviv_domain = to_v2_context(context);
125 	int mtlb_entry, stlb_entry;
126 
127 	if (size != SZ_4K)
128 		return -EINVAL;
129 
130 	mtlb_entry = (iova & MMUv2_MTLB_MASK) >> MMUv2_MTLB_SHIFT;
131 	stlb_entry = (iova & MMUv2_STLB_MASK) >> MMUv2_STLB_SHIFT;
132 
133 	etnaviv_domain->stlb_cpu[mtlb_entry][stlb_entry] = MMUv2_PTE_EXCEPTION;
134 
135 	return SZ_4K;
136 }
137 
138 static size_t etnaviv_iommuv2_dump_size(struct etnaviv_iommu_context *context)
139 {
140 	struct etnaviv_iommuv2_context *v2_context = to_v2_context(context);
141 	size_t dump_size = SZ_4K;
142 	int i;
143 
144 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++)
145 		if (v2_context->mtlb_cpu[i] & MMUv2_PTE_PRESENT)
146 			dump_size += SZ_4K;
147 
148 	return dump_size;
149 }
150 
151 static void etnaviv_iommuv2_dump(struct etnaviv_iommu_context *context, void *buf)
152 {
153 	struct etnaviv_iommuv2_context *v2_context = to_v2_context(context);
154 	int i;
155 
156 	memcpy(buf, v2_context->mtlb_cpu, SZ_4K);
157 	buf += SZ_4K;
158 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++, buf += SZ_4K)
159 		if (v2_context->mtlb_cpu[i] & MMUv2_PTE_PRESENT)
160 			memcpy(buf, v2_context->stlb_cpu[i], SZ_4K);
161 }
162 
163 static void etnaviv_iommuv2_restore_nonsec(struct etnaviv_gpu *gpu,
164 	struct etnaviv_iommu_context *context)
165 {
166 	struct etnaviv_iommuv2_context *v2_context = to_v2_context(context);
167 	u16 prefetch;
168 
169 	/* If the MMU is already enabled the state is still there. */
170 	if (gpu_read(gpu, VIVS_MMUv2_CONTROL) & VIVS_MMUv2_CONTROL_ENABLE)
171 		return;
172 
173 	prefetch = etnaviv_buffer_config_mmuv2(gpu,
174 				(u32)v2_context->mtlb_dma,
175 				(u32)context->global->bad_page_dma);
176 	etnaviv_gpu_start_fe(gpu, (u32)etnaviv_cmdbuf_get_pa(&gpu->buffer),
177 			     prefetch);
178 	etnaviv_gpu_wait_idle(gpu, 100);
179 
180 	gpu_write(gpu, VIVS_MMUv2_CONTROL, VIVS_MMUv2_CONTROL_ENABLE);
181 }
182 
183 static void etnaviv_iommuv2_restore_sec(struct etnaviv_gpu *gpu,
184 	struct etnaviv_iommu_context *context)
185 {
186 	struct etnaviv_iommuv2_context *v2_context = to_v2_context(context);
187 	u16 prefetch;
188 
189 	/* If the MMU is already enabled the state is still there. */
190 	if (gpu_read(gpu, VIVS_MMUv2_SEC_CONTROL) & VIVS_MMUv2_SEC_CONTROL_ENABLE)
191 		return;
192 
193 	gpu_write(gpu, VIVS_MMUv2_PTA_ADDRESS_LOW,
194 		  lower_32_bits(context->global->v2.pta_dma));
195 	gpu_write(gpu, VIVS_MMUv2_PTA_ADDRESS_HIGH,
196 		  upper_32_bits(context->global->v2.pta_dma));
197 	gpu_write(gpu, VIVS_MMUv2_PTA_CONTROL, VIVS_MMUv2_PTA_CONTROL_ENABLE);
198 
199 	gpu_write(gpu, VIVS_MMUv2_NONSEC_SAFE_ADDR_LOW,
200 		  lower_32_bits(context->global->bad_page_dma));
201 	gpu_write(gpu, VIVS_MMUv2_SEC_SAFE_ADDR_LOW,
202 		  lower_32_bits(context->global->bad_page_dma));
203 	gpu_write(gpu, VIVS_MMUv2_SAFE_ADDRESS_CONFIG,
204 		  VIVS_MMUv2_SAFE_ADDRESS_CONFIG_NON_SEC_SAFE_ADDR_HIGH(
205 		  upper_32_bits(context->global->bad_page_dma)) |
206 		  VIVS_MMUv2_SAFE_ADDRESS_CONFIG_SEC_SAFE_ADDR_HIGH(
207 		  upper_32_bits(context->global->bad_page_dma)));
208 
209 	context->global->v2.pta_cpu[v2_context->id] = v2_context->mtlb_dma |
210 				 	 VIVS_MMUv2_CONFIGURATION_MODE_MODE4_K;
211 
212 	/* trigger a PTA load through the FE */
213 	prefetch = etnaviv_buffer_config_pta(gpu, v2_context->id);
214 	etnaviv_gpu_start_fe(gpu, (u32)etnaviv_cmdbuf_get_pa(&gpu->buffer),
215 			     prefetch);
216 	etnaviv_gpu_wait_idle(gpu, 100);
217 
218 	gpu_write(gpu, VIVS_MMUv2_SEC_CONTROL, VIVS_MMUv2_SEC_CONTROL_ENABLE);
219 }
220 
221 u32 etnaviv_iommuv2_get_mtlb_addr(struct etnaviv_iommu_context *context)
222 {
223 	struct etnaviv_iommuv2_context *v2_context = to_v2_context(context);
224 
225 	return v2_context->mtlb_dma;
226 }
227 
228 unsigned short etnaviv_iommuv2_get_pta_id(struct etnaviv_iommu_context *context)
229 {
230 	struct etnaviv_iommuv2_context *v2_context = to_v2_context(context);
231 
232 	return v2_context->id;
233 }
234 static void etnaviv_iommuv2_restore(struct etnaviv_gpu *gpu,
235 				    struct etnaviv_iommu_context *context)
236 {
237 	switch (gpu->sec_mode) {
238 	case ETNA_SEC_NONE:
239 		etnaviv_iommuv2_restore_nonsec(gpu, context);
240 		break;
241 	case ETNA_SEC_KERNEL:
242 		etnaviv_iommuv2_restore_sec(gpu, context);
243 		break;
244 	default:
245 		WARN(1, "unhandled GPU security mode\n");
246 		break;
247 	}
248 }
249 
250 const struct etnaviv_iommu_ops etnaviv_iommuv2_ops = {
251 	.free = etnaviv_iommuv2_free,
252 	.map = etnaviv_iommuv2_map,
253 	.unmap = etnaviv_iommuv2_unmap,
254 	.dump_size = etnaviv_iommuv2_dump_size,
255 	.dump = etnaviv_iommuv2_dump,
256 	.restore = etnaviv_iommuv2_restore,
257 };
258 
259 struct etnaviv_iommu_context *
260 etnaviv_iommuv2_context_alloc(struct etnaviv_iommu_global *global)
261 {
262 	struct etnaviv_iommuv2_context *v2_context;
263 	struct etnaviv_iommu_context *context;
264 
265 	v2_context = vzalloc(sizeof(*v2_context));
266 	if (!v2_context)
267 		return NULL;
268 
269 	mutex_lock(&global->lock);
270 	v2_context->id = find_first_zero_bit(global->v2.pta_alloc,
271 					     ETNAVIV_PTA_ENTRIES);
272 	if (v2_context->id < ETNAVIV_PTA_ENTRIES) {
273 		set_bit(v2_context->id, global->v2.pta_alloc);
274 	} else {
275 		mutex_unlock(&global->lock);
276 		goto out_free;
277 	}
278 	mutex_unlock(&global->lock);
279 
280 	v2_context->mtlb_cpu = dma_alloc_wc(global->dev, SZ_4K,
281 					    &v2_context->mtlb_dma, GFP_KERNEL);
282 	if (!v2_context->mtlb_cpu)
283 		goto out_free_id;
284 
285 	memset32(v2_context->mtlb_cpu, MMUv2_PTE_EXCEPTION,
286 		 MMUv2_MAX_STLB_ENTRIES);
287 
288 	global->v2.pta_cpu[v2_context->id] = v2_context->mtlb_dma;
289 
290 	context = &v2_context->base;
291 	context->global = global;
292 	kref_init(&context->refcount);
293 	mutex_init(&context->lock);
294 	INIT_LIST_HEAD(&context->mappings);
295 	drm_mm_init(&context->mm, SZ_4K, (u64)SZ_1G * 4 - SZ_4K);
296 
297 	return context;
298 
299 out_free_id:
300 	clear_bit(v2_context->id, global->v2.pta_alloc);
301 out_free:
302 	vfree(v2_context);
303 	return NULL;
304 }
305