xref: /openbmc/linux/drivers/gpu/drm/etnaviv/etnaviv_iommu_v2.c (revision 7a846d3c43b0b6d04300be9ba666b102b57a391a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2016-2018 Etnaviv Project
4  */
5 
6 #include <linux/platform_device.h>
7 #include <linux/sizes.h>
8 #include <linux/slab.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/bitops.h>
11 
12 #include "etnaviv_cmdbuf.h"
13 #include "etnaviv_gpu.h"
14 #include "etnaviv_mmu.h"
15 #include "etnaviv_iommu.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_domain {
31 	struct etnaviv_iommu_domain base;
32 	/* P(age) T(able) A(rray) */
33 	u64 *pta_cpu;
34 	dma_addr_t pta_dma;
35 	/* M(aster) TLB aka first level pagetable */
36 	u32 *mtlb_cpu;
37 	dma_addr_t mtlb_dma;
38 	/* S(lave) TLB aka second level pagetable */
39 	u32 *stlb_cpu[MMUv2_MAX_STLB_ENTRIES];
40 	dma_addr_t stlb_dma[MMUv2_MAX_STLB_ENTRIES];
41 };
42 
43 static struct etnaviv_iommuv2_domain *
44 to_etnaviv_domain(struct etnaviv_iommu_domain *domain)
45 {
46 	return container_of(domain, struct etnaviv_iommuv2_domain, base);
47 }
48 
49 static int
50 etnaviv_iommuv2_ensure_stlb(struct etnaviv_iommuv2_domain *etnaviv_domain,
51 			    int stlb)
52 {
53 	if (etnaviv_domain->stlb_cpu[stlb])
54 		return 0;
55 
56 	etnaviv_domain->stlb_cpu[stlb] =
57 			dma_alloc_wc(etnaviv_domain->base.dev, SZ_4K,
58 				     &etnaviv_domain->stlb_dma[stlb],
59 				     GFP_KERNEL);
60 
61 	if (!etnaviv_domain->stlb_cpu[stlb])
62 		return -ENOMEM;
63 
64 	memset32(etnaviv_domain->stlb_cpu[stlb], MMUv2_PTE_EXCEPTION,
65 		 SZ_4K / sizeof(u32));
66 
67 	etnaviv_domain->mtlb_cpu[stlb] = etnaviv_domain->stlb_dma[stlb] |
68 						      MMUv2_PTE_PRESENT;
69 	return 0;
70 }
71 
72 static int etnaviv_iommuv2_map(struct etnaviv_iommu_domain *domain,
73 			       unsigned long iova, phys_addr_t paddr,
74 			       size_t size, int prot)
75 {
76 	struct etnaviv_iommuv2_domain *etnaviv_domain =
77 			to_etnaviv_domain(domain);
78 	int mtlb_entry, stlb_entry, ret;
79 	u32 entry = lower_32_bits(paddr) | MMUv2_PTE_PRESENT;
80 
81 	if (size != SZ_4K)
82 		return -EINVAL;
83 
84 	if (IS_ENABLED(CONFIG_PHYS_ADDR_T_64BIT))
85 		entry |= (upper_32_bits(paddr) & 0xff) << 4;
86 
87 	if (prot & ETNAVIV_PROT_WRITE)
88 		entry |= MMUv2_PTE_WRITEABLE;
89 
90 	mtlb_entry = (iova & MMUv2_MTLB_MASK) >> MMUv2_MTLB_SHIFT;
91 	stlb_entry = (iova & MMUv2_STLB_MASK) >> MMUv2_STLB_SHIFT;
92 
93 	ret = etnaviv_iommuv2_ensure_stlb(etnaviv_domain, mtlb_entry);
94 	if (ret)
95 		return ret;
96 
97 	etnaviv_domain->stlb_cpu[mtlb_entry][stlb_entry] = entry;
98 
99 	return 0;
100 }
101 
102 static size_t etnaviv_iommuv2_unmap(struct etnaviv_iommu_domain *domain,
103 				    unsigned long iova, size_t size)
104 {
105 	struct etnaviv_iommuv2_domain *etnaviv_domain =
106 			to_etnaviv_domain(domain);
107 	int mtlb_entry, stlb_entry;
108 
109 	if (size != SZ_4K)
110 		return -EINVAL;
111 
112 	mtlb_entry = (iova & MMUv2_MTLB_MASK) >> MMUv2_MTLB_SHIFT;
113 	stlb_entry = (iova & MMUv2_STLB_MASK) >> MMUv2_STLB_SHIFT;
114 
115 	etnaviv_domain->stlb_cpu[mtlb_entry][stlb_entry] = MMUv2_PTE_EXCEPTION;
116 
117 	return SZ_4K;
118 }
119 
120 static int etnaviv_iommuv2_init(struct etnaviv_iommuv2_domain *etnaviv_domain)
121 {
122 	u32 *p;
123 	int ret, i;
124 
125 	/* allocate scratch page */
126 	etnaviv_domain->base.bad_page_cpu =
127 			dma_alloc_wc(etnaviv_domain->base.dev, SZ_4K,
128 				     &etnaviv_domain->base.bad_page_dma,
129 				     GFP_KERNEL);
130 	if (!etnaviv_domain->base.bad_page_cpu) {
131 		ret = -ENOMEM;
132 		goto fail_mem;
133 	}
134 	p = etnaviv_domain->base.bad_page_cpu;
135 	for (i = 0; i < SZ_4K / 4; i++)
136 		*p++ = 0xdead55aa;
137 
138 	etnaviv_domain->pta_cpu = dma_alloc_wc(etnaviv_domain->base.dev,
139 					       SZ_4K, &etnaviv_domain->pta_dma,
140 					       GFP_KERNEL);
141 	if (!etnaviv_domain->pta_cpu) {
142 		ret = -ENOMEM;
143 		goto fail_mem;
144 	}
145 
146 	etnaviv_domain->mtlb_cpu = dma_alloc_wc(etnaviv_domain->base.dev,
147 						SZ_4K, &etnaviv_domain->mtlb_dma,
148 						GFP_KERNEL);
149 	if (!etnaviv_domain->mtlb_cpu) {
150 		ret = -ENOMEM;
151 		goto fail_mem;
152 	}
153 
154 	memset32(etnaviv_domain->mtlb_cpu, MMUv2_PTE_EXCEPTION,
155 		 MMUv2_MAX_STLB_ENTRIES);
156 
157 	return 0;
158 
159 fail_mem:
160 	if (etnaviv_domain->base.bad_page_cpu)
161 		dma_free_wc(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_wc(etnaviv_domain->base.dev, SZ_4K,
167 			    etnaviv_domain->pta_cpu, etnaviv_domain->pta_dma);
168 
169 	if (etnaviv_domain->mtlb_cpu)
170 		dma_free_wc(etnaviv_domain->base.dev, SZ_4K,
171 			    etnaviv_domain->mtlb_cpu, etnaviv_domain->mtlb_dma);
172 
173 	return ret;
174 }
175 
176 static void etnaviv_iommuv2_domain_free(struct etnaviv_iommu_domain *domain)
177 {
178 	struct etnaviv_iommuv2_domain *etnaviv_domain =
179 			to_etnaviv_domain(domain);
180 	int i;
181 
182 	dma_free_wc(etnaviv_domain->base.dev, SZ_4K,
183 		    etnaviv_domain->base.bad_page_cpu,
184 		    etnaviv_domain->base.bad_page_dma);
185 
186 	dma_free_wc(etnaviv_domain->base.dev, SZ_4K,
187 		    etnaviv_domain->pta_cpu, etnaviv_domain->pta_dma);
188 
189 	dma_free_wc(etnaviv_domain->base.dev, SZ_4K,
190 		    etnaviv_domain->mtlb_cpu, etnaviv_domain->mtlb_dma);
191 
192 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++) {
193 		if (etnaviv_domain->stlb_cpu[i])
194 			dma_free_wc(etnaviv_domain->base.dev, SZ_4K,
195 				    etnaviv_domain->stlb_cpu[i],
196 				    etnaviv_domain->stlb_dma[i]);
197 	}
198 
199 	vfree(etnaviv_domain);
200 }
201 
202 static size_t etnaviv_iommuv2_dump_size(struct etnaviv_iommu_domain *domain)
203 {
204 	struct etnaviv_iommuv2_domain *etnaviv_domain =
205 			to_etnaviv_domain(domain);
206 	size_t dump_size = SZ_4K;
207 	int i;
208 
209 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++)
210 		if (etnaviv_domain->mtlb_cpu[i] & MMUv2_PTE_PRESENT)
211 			dump_size += SZ_4K;
212 
213 	return dump_size;
214 }
215 
216 static void etnaviv_iommuv2_dump(struct etnaviv_iommu_domain *domain, void *buf)
217 {
218 	struct etnaviv_iommuv2_domain *etnaviv_domain =
219 			to_etnaviv_domain(domain);
220 	int i;
221 
222 	memcpy(buf, etnaviv_domain->mtlb_cpu, SZ_4K);
223 	buf += SZ_4K;
224 	for (i = 0; i < MMUv2_MAX_STLB_ENTRIES; i++, buf += SZ_4K)
225 		if (etnaviv_domain->mtlb_cpu[i] & MMUv2_PTE_PRESENT)
226 			memcpy(buf, etnaviv_domain->stlb_cpu[i], SZ_4K);
227 }
228 
229 static void etnaviv_iommuv2_restore_nonsec(struct etnaviv_gpu *gpu)
230 {
231 	struct etnaviv_iommuv2_domain *etnaviv_domain =
232 			to_etnaviv_domain(gpu->mmu->domain);
233 	u16 prefetch;
234 
235 	/* If the MMU is already enabled the state is still there. */
236 	if (gpu_read(gpu, VIVS_MMUv2_CONTROL) & VIVS_MMUv2_CONTROL_ENABLE)
237 		return;
238 
239 	prefetch = etnaviv_buffer_config_mmuv2(gpu,
240 				(u32)etnaviv_domain->mtlb_dma,
241 				(u32)etnaviv_domain->base.bad_page_dma);
242 	etnaviv_gpu_start_fe(gpu, (u32)etnaviv_cmdbuf_get_pa(&gpu->buffer),
243 			     prefetch);
244 	etnaviv_gpu_wait_idle(gpu, 100);
245 
246 	gpu_write(gpu, VIVS_MMUv2_CONTROL, VIVS_MMUv2_CONTROL_ENABLE);
247 }
248 
249 static void etnaviv_iommuv2_restore_sec(struct etnaviv_gpu *gpu)
250 {
251 	struct etnaviv_iommuv2_domain *etnaviv_domain =
252 				to_etnaviv_domain(gpu->mmu->domain);
253 	u16 prefetch;
254 
255 	/* If the MMU is already enabled the state is still there. */
256 	if (gpu_read(gpu, VIVS_MMUv2_SEC_CONTROL) & VIVS_MMUv2_SEC_CONTROL_ENABLE)
257 		return;
258 
259 	gpu_write(gpu, VIVS_MMUv2_PTA_ADDRESS_LOW,
260 		  lower_32_bits(etnaviv_domain->pta_dma));
261 	gpu_write(gpu, VIVS_MMUv2_PTA_ADDRESS_HIGH,
262 		  upper_32_bits(etnaviv_domain->pta_dma));
263 	gpu_write(gpu, VIVS_MMUv2_PTA_CONTROL, VIVS_MMUv2_PTA_CONTROL_ENABLE);
264 
265 	gpu_write(gpu, VIVS_MMUv2_NONSEC_SAFE_ADDR_LOW,
266 		  lower_32_bits(etnaviv_domain->base.bad_page_dma));
267 	gpu_write(gpu, VIVS_MMUv2_SEC_SAFE_ADDR_LOW,
268 		  lower_32_bits(etnaviv_domain->base.bad_page_dma));
269 	gpu_write(gpu, VIVS_MMUv2_SAFE_ADDRESS_CONFIG,
270 		  VIVS_MMUv2_SAFE_ADDRESS_CONFIG_NON_SEC_SAFE_ADDR_HIGH(
271 		  upper_32_bits(etnaviv_domain->base.bad_page_dma)) |
272 		  VIVS_MMUv2_SAFE_ADDRESS_CONFIG_SEC_SAFE_ADDR_HIGH(
273 		  upper_32_bits(etnaviv_domain->base.bad_page_dma)));
274 
275 	etnaviv_domain->pta_cpu[0] = etnaviv_domain->mtlb_dma |
276 				     VIVS_MMUv2_CONFIGURATION_MODE_MODE4_K;
277 
278 	/* trigger a PTA load through the FE */
279 	prefetch = etnaviv_buffer_config_pta(gpu);
280 	etnaviv_gpu_start_fe(gpu, (u32)etnaviv_cmdbuf_get_pa(&gpu->buffer),
281 			     prefetch);
282 	etnaviv_gpu_wait_idle(gpu, 100);
283 
284 	gpu_write(gpu, VIVS_MMUv2_SEC_CONTROL, VIVS_MMUv2_SEC_CONTROL_ENABLE);
285 }
286 
287 void etnaviv_iommuv2_restore(struct etnaviv_gpu *gpu)
288 {
289 	switch (gpu->sec_mode) {
290 	case ETNA_SEC_NONE:
291 		etnaviv_iommuv2_restore_nonsec(gpu);
292 		break;
293 	case ETNA_SEC_KERNEL:
294 		etnaviv_iommuv2_restore_sec(gpu);
295 		break;
296 	default:
297 		WARN(1, "unhandled GPU security mode\n");
298 		break;
299 	}
300 }
301 
302 static const struct etnaviv_iommu_domain_ops etnaviv_iommuv2_ops = {
303 	.free = etnaviv_iommuv2_domain_free,
304 	.map = etnaviv_iommuv2_map,
305 	.unmap = etnaviv_iommuv2_unmap,
306 	.dump_size = etnaviv_iommuv2_dump_size,
307 	.dump = etnaviv_iommuv2_dump,
308 };
309 
310 struct etnaviv_iommu_domain *
311 etnaviv_iommuv2_domain_alloc(struct etnaviv_gpu *gpu)
312 {
313 	struct etnaviv_iommuv2_domain *etnaviv_domain;
314 	struct etnaviv_iommu_domain *domain;
315 	int ret;
316 
317 	etnaviv_domain = vzalloc(sizeof(*etnaviv_domain));
318 	if (!etnaviv_domain)
319 		return NULL;
320 
321 	domain = &etnaviv_domain->base;
322 
323 	domain->dev = gpu->dev;
324 	domain->base = 0;
325 	domain->size = (u64)SZ_1G * 4;
326 	domain->ops = &etnaviv_iommuv2_ops;
327 
328 	ret = etnaviv_iommuv2_init(etnaviv_domain);
329 	if (ret)
330 		goto out_free;
331 
332 	return &etnaviv_domain->base;
333 
334 out_free:
335 	vfree(etnaviv_domain);
336 	return NULL;
337 }
338