xref: /openbmc/linux/drivers/gpu/drm/etnaviv/etnaviv_iommu_v2.c (revision e33bbe69149b802c0c77bfb822685772f85388ca)
1 /*
2  * Copyright (C) 2016 Etnaviv Project
3   *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License version 2 as published by
6  * the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program.  If not, see <http://www.gnu.org/licenses/>.
15  */
16 
17 #include <linux/platform_device.h>
18 #include <linux/sizes.h>
19 #include <linux/slab.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/bitops.h>
22 
23 #include "etnaviv_cmdbuf.h"
24 #include "etnaviv_gpu.h"
25 #include "etnaviv_mmu.h"
26 #include "etnaviv_iommu.h"
27 #include "state.xml.h"
28 #include "state_hi.xml.h"
29 
30 #define MMUv2_PTE_PRESENT		BIT(0)
31 #define MMUv2_PTE_EXCEPTION		BIT(1)
32 #define MMUv2_PTE_WRITEABLE		BIT(2)
33 
34 #define MMUv2_MTLB_MASK			0xffc00000
35 #define MMUv2_MTLB_SHIFT		22
36 #define MMUv2_STLB_MASK			0x003ff000
37 #define MMUv2_STLB_SHIFT		12
38 
39 #define MMUv2_MAX_STLB_ENTRIES		1024
40 
41 struct etnaviv_iommuv2_domain {
42 	struct etnaviv_iommu_domain base;
43 	/* P(age) T(able) A(rray) */
44 	u64 *pta_cpu;
45 	dma_addr_t pta_dma;
46 	/* M(aster) TLB aka first level pagetable */
47 	u32 *mtlb_cpu;
48 	dma_addr_t mtlb_dma;
49 	/* S(lave) TLB aka second level pagetable */
50 	u32 *stlb_cpu[1024];
51 	dma_addr_t stlb_dma[1024];
52 };
53 
54 static struct etnaviv_iommuv2_domain *
55 to_etnaviv_domain(struct etnaviv_iommu_domain *domain)
56 {
57 	return container_of(domain, struct etnaviv_iommuv2_domain, base);
58 }
59 
60 static int etnaviv_iommuv2_map(struct etnaviv_iommu_domain *domain,
61 			       unsigned long iova, phys_addr_t paddr,
62 			       size_t size, int prot)
63 {
64 	struct etnaviv_iommuv2_domain *etnaviv_domain =
65 			to_etnaviv_domain(domain);
66 	int mtlb_entry, stlb_entry;
67 	u32 entry = (u32)paddr | MMUv2_PTE_PRESENT;
68 
69 	if (size != SZ_4K)
70 		return -EINVAL;
71 
72 	if (prot & ETNAVIV_PROT_WRITE)
73 		entry |= MMUv2_PTE_WRITEABLE;
74 
75 	mtlb_entry = (iova & MMUv2_MTLB_MASK) >> MMUv2_MTLB_SHIFT;
76 	stlb_entry = (iova & MMUv2_STLB_MASK) >> MMUv2_STLB_SHIFT;
77 
78 	etnaviv_domain->stlb_cpu[mtlb_entry][stlb_entry] = entry;
79 
80 	return 0;
81 }
82 
83 static size_t etnaviv_iommuv2_unmap(struct etnaviv_iommu_domain *domain,
84 				    unsigned long iova, size_t size)
85 {
86 	struct etnaviv_iommuv2_domain *etnaviv_domain =
87 			to_etnaviv_domain(domain);
88 	int mtlb_entry, stlb_entry;
89 
90 	if (size != SZ_4K)
91 		return -EINVAL;
92 
93 	mtlb_entry = (iova & MMUv2_MTLB_MASK) >> MMUv2_MTLB_SHIFT;
94 	stlb_entry = (iova & MMUv2_STLB_MASK) >> MMUv2_STLB_SHIFT;
95 
96 	etnaviv_domain->stlb_cpu[mtlb_entry][stlb_entry] = MMUv2_PTE_EXCEPTION;
97 
98 	return SZ_4K;
99 }
100 
101 static int etnaviv_iommuv2_init(struct etnaviv_iommuv2_domain *etnaviv_domain)
102 {
103 	u32 *p;
104 	int ret, i, j;
105 
106 	/* allocate scratch page */
107 	etnaviv_domain->base.bad_page_cpu = dma_alloc_coherent(
108 						etnaviv_domain->base.dev,
109 						SZ_4K,
110 						&etnaviv_domain->base.bad_page_dma,
111 						GFP_KERNEL);
112 	if (!etnaviv_domain->base.bad_page_cpu) {
113 		ret = -ENOMEM;
114 		goto fail_mem;
115 	}
116 	p = etnaviv_domain->base.bad_page_cpu;
117 	for (i = 0; i < SZ_4K / 4; i++)
118 		*p++ = 0xdead55aa;
119 
120 	etnaviv_domain->pta_cpu = dma_alloc_coherent(etnaviv_domain->base.dev,
121 						     SZ_4K,
122 						     &etnaviv_domain->pta_dma,
123 						     GFP_KERNEL);
124 	if (!etnaviv_domain->pta_cpu) {
125 		ret = -ENOMEM;
126 		goto fail_mem;
127 	}
128 
129 	etnaviv_domain->mtlb_cpu = dma_alloc_coherent(etnaviv_domain->base.dev,
130 						  SZ_4K,
131 						  &etnaviv_domain->mtlb_dma,
132 						  GFP_KERNEL);
133 	if (!etnaviv_domain->mtlb_cpu) {
134 		ret = -ENOMEM;
135 		goto fail_mem;
136 	}
137 
138 	/* pre-populate STLB pages (may want to switch to on-demand later) */
139 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++) {
140 		etnaviv_domain->stlb_cpu[i] =
141 				dma_alloc_coherent(etnaviv_domain->base.dev,
142 						   SZ_4K,
143 						   &etnaviv_domain->stlb_dma[i],
144 						   GFP_KERNEL);
145 		if (!etnaviv_domain->stlb_cpu[i]) {
146 			ret = -ENOMEM;
147 			goto fail_mem;
148 		}
149 		p = etnaviv_domain->stlb_cpu[i];
150 		for (j = 0; j < SZ_4K / 4; j++)
151 			*p++ = MMUv2_PTE_EXCEPTION;
152 
153 		etnaviv_domain->mtlb_cpu[i] = etnaviv_domain->stlb_dma[i] |
154 					      MMUv2_PTE_PRESENT;
155 	}
156 
157 	return 0;
158 
159 fail_mem:
160 	if (etnaviv_domain->base.bad_page_cpu)
161 		dma_free_coherent(etnaviv_domain->base.dev, SZ_4K,
162 				  etnaviv_domain->base.bad_page_cpu,
163 				  etnaviv_domain->base.bad_page_dma);
164 
165 	if (etnaviv_domain->pta_cpu)
166 		dma_free_coherent(etnaviv_domain->base.dev, SZ_4K,
167 				  etnaviv_domain->pta_cpu,
168 				  etnaviv_domain->pta_dma);
169 
170 	if (etnaviv_domain->mtlb_cpu)
171 		dma_free_coherent(etnaviv_domain->base.dev, SZ_4K,
172 				  etnaviv_domain->mtlb_cpu,
173 				  etnaviv_domain->mtlb_dma);
174 
175 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++) {
176 		if (etnaviv_domain->stlb_cpu[i])
177 			dma_free_coherent(etnaviv_domain->base.dev, SZ_4K,
178 					  etnaviv_domain->stlb_cpu[i],
179 					  etnaviv_domain->stlb_dma[i]);
180 	}
181 
182 	return ret;
183 }
184 
185 static void etnaviv_iommuv2_domain_free(struct etnaviv_iommu_domain *domain)
186 {
187 	struct etnaviv_iommuv2_domain *etnaviv_domain =
188 			to_etnaviv_domain(domain);
189 	int i;
190 
191 	dma_free_coherent(etnaviv_domain->base.dev, SZ_4K,
192 			  etnaviv_domain->base.bad_page_cpu,
193 			  etnaviv_domain->base.bad_page_dma);
194 
195 	dma_free_coherent(etnaviv_domain->base.dev, SZ_4K,
196 			  etnaviv_domain->pta_cpu,
197 			  etnaviv_domain->pta_dma);
198 
199 	dma_free_coherent(etnaviv_domain->base.dev, SZ_4K,
200 			  etnaviv_domain->mtlb_cpu,
201 			  etnaviv_domain->mtlb_dma);
202 
203 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++) {
204 		if (etnaviv_domain->stlb_cpu[i])
205 			dma_free_coherent(etnaviv_domain->base.dev, SZ_4K,
206 					  etnaviv_domain->stlb_cpu[i],
207 					  etnaviv_domain->stlb_dma[i]);
208 	}
209 
210 	vfree(etnaviv_domain);
211 }
212 
213 static size_t etnaviv_iommuv2_dump_size(struct etnaviv_iommu_domain *domain)
214 {
215 	struct etnaviv_iommuv2_domain *etnaviv_domain =
216 			to_etnaviv_domain(domain);
217 	size_t dump_size = SZ_4K;
218 	int i;
219 
220 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++)
221 		if (etnaviv_domain->mtlb_cpu[i] & MMUv2_PTE_PRESENT)
222 			dump_size += SZ_4K;
223 
224 	return dump_size;
225 }
226 
227 static void etnaviv_iommuv2_dump(struct etnaviv_iommu_domain *domain, void *buf)
228 {
229 	struct etnaviv_iommuv2_domain *etnaviv_domain =
230 			to_etnaviv_domain(domain);
231 	int i;
232 
233 	memcpy(buf, etnaviv_domain->mtlb_cpu, SZ_4K);
234 	buf += SZ_4K;
235 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++, buf += SZ_4K)
236 		if (etnaviv_domain->mtlb_cpu[i] & MMUv2_PTE_PRESENT)
237 			memcpy(buf, etnaviv_domain->stlb_cpu[i], SZ_4K);
238 }
239 
240 static void etnaviv_iommuv2_restore_nonsec(struct etnaviv_gpu *gpu)
241 {
242 	struct etnaviv_iommuv2_domain *etnaviv_domain =
243 			to_etnaviv_domain(gpu->mmu->domain);
244 	u16 prefetch;
245 
246 	/* If the MMU is already enabled the state is still there. */
247 	if (gpu_read(gpu, VIVS_MMUv2_CONTROL) & VIVS_MMUv2_CONTROL_ENABLE)
248 		return;
249 
250 	prefetch = etnaviv_buffer_config_mmuv2(gpu,
251 				(u32)etnaviv_domain->mtlb_dma,
252 				(u32)etnaviv_domain->base.bad_page_dma);
253 	etnaviv_gpu_start_fe(gpu, (u32)etnaviv_cmdbuf_get_pa(&gpu->buffer),
254 			     prefetch);
255 	etnaviv_gpu_wait_idle(gpu, 100);
256 
257 	gpu_write(gpu, VIVS_MMUv2_CONTROL, VIVS_MMUv2_CONTROL_ENABLE);
258 }
259 
260 static void etnaviv_iommuv2_restore_sec(struct etnaviv_gpu *gpu)
261 {
262 	struct etnaviv_iommuv2_domain *etnaviv_domain =
263 				to_etnaviv_domain(gpu->mmu->domain);
264 	u16 prefetch;
265 
266 	/* If the MMU is already enabled the state is still there. */
267 	if (gpu_read(gpu, VIVS_MMUv2_SEC_CONTROL) & VIVS_MMUv2_SEC_CONTROL_ENABLE)
268 		return;
269 
270 	gpu_write(gpu, VIVS_MMUv2_PTA_ADDRESS_LOW,
271 		  lower_32_bits(etnaviv_domain->pta_dma));
272 	gpu_write(gpu, VIVS_MMUv2_PTA_ADDRESS_HIGH,
273 		  upper_32_bits(etnaviv_domain->pta_dma));
274 	gpu_write(gpu, VIVS_MMUv2_PTA_CONTROL, VIVS_MMUv2_PTA_CONTROL_ENABLE);
275 
276 	gpu_write(gpu, VIVS_MMUv2_NONSEC_SAFE_ADDR_LOW,
277 		  lower_32_bits(etnaviv_domain->base.bad_page_dma));
278 	gpu_write(gpu, VIVS_MMUv2_SEC_SAFE_ADDR_LOW,
279 		  lower_32_bits(etnaviv_domain->base.bad_page_dma));
280 	gpu_write(gpu, VIVS_MMUv2_SAFE_ADDRESS_CONFIG,
281 		  VIVS_MMUv2_SAFE_ADDRESS_CONFIG_NON_SEC_SAFE_ADDR_HIGH(
282 		  upper_32_bits(etnaviv_domain->base.bad_page_dma)) |
283 		  VIVS_MMUv2_SAFE_ADDRESS_CONFIG_SEC_SAFE_ADDR_HIGH(
284 		  upper_32_bits(etnaviv_domain->base.bad_page_dma)));
285 
286 	etnaviv_domain->pta_cpu[0] = etnaviv_domain->mtlb_dma |
287 				     VIVS_MMUv2_CONFIGURATION_MODE_MODE4_K;
288 
289 	/* trigger a PTA load through the FE */
290 	prefetch = etnaviv_buffer_config_pta(gpu);
291 	etnaviv_gpu_start_fe(gpu, (u32)etnaviv_cmdbuf_get_pa(&gpu->buffer),
292 			     prefetch);
293 	etnaviv_gpu_wait_idle(gpu, 100);
294 
295 	gpu_write(gpu, VIVS_MMUv2_SEC_CONTROL, VIVS_MMUv2_SEC_CONTROL_ENABLE);
296 }
297 
298 void etnaviv_iommuv2_restore(struct etnaviv_gpu *gpu)
299 {
300 	switch (gpu->sec_mode) {
301 	case ETNA_SEC_NONE:
302 		etnaviv_iommuv2_restore_nonsec(gpu);
303 		break;
304 	case ETNA_SEC_KERNEL:
305 		etnaviv_iommuv2_restore_sec(gpu);
306 		break;
307 	default:
308 		WARN(1, "unhandled GPU security mode\n");
309 		break;
310 	}
311 }
312 
313 static const struct etnaviv_iommu_domain_ops etnaviv_iommuv2_ops = {
314 	.free = etnaviv_iommuv2_domain_free,
315 	.map = etnaviv_iommuv2_map,
316 	.unmap = etnaviv_iommuv2_unmap,
317 	.dump_size = etnaviv_iommuv2_dump_size,
318 	.dump = etnaviv_iommuv2_dump,
319 };
320 
321 struct etnaviv_iommu_domain *
322 etnaviv_iommuv2_domain_alloc(struct etnaviv_gpu *gpu)
323 {
324 	struct etnaviv_iommuv2_domain *etnaviv_domain;
325 	struct etnaviv_iommu_domain *domain;
326 	int ret;
327 
328 	etnaviv_domain = vzalloc(sizeof(*etnaviv_domain));
329 	if (!etnaviv_domain)
330 		return NULL;
331 
332 	domain = &etnaviv_domain->base;
333 
334 	domain->dev = gpu->dev;
335 	domain->base = 0;
336 	domain->size = (u64)SZ_1G * 4;
337 	domain->ops = &etnaviv_iommuv2_ops;
338 
339 	ret = etnaviv_iommuv2_init(etnaviv_domain);
340 	if (ret)
341 		goto out_free;
342 
343 	return &etnaviv_domain->base;
344 
345 out_free:
346 	vfree(etnaviv_domain);
347 	return NULL;
348 }
349