1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2014-2018 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 
12 #include "etnaviv_gpu.h"
13 #include "etnaviv_mmu.h"
14 #include "state_hi.xml.h"
15 
16 #define PT_SIZE		SZ_2M
17 #define PT_ENTRIES	(PT_SIZE / sizeof(u32))
18 
19 #define GPU_MEM_START	0x80000000
20 
21 struct etnaviv_iommuv1_context {
22 	struct etnaviv_iommu_context base;
23 	u32 *pgtable_cpu;
24 	dma_addr_t pgtable_dma;
25 };
26 
27 static struct etnaviv_iommuv1_context *
28 to_v1_context(struct etnaviv_iommu_context *context)
29 {
30 	return container_of(context, struct etnaviv_iommuv1_context, base);
31 }
32 
33 static void etnaviv_iommuv1_free(struct etnaviv_iommu_context *context)
34 {
35 	struct etnaviv_iommuv1_context *v1_context = to_v1_context(context);
36 
37 	drm_mm_takedown(&context->mm);
38 
39 	dma_free_wc(context->global->dev, PT_SIZE, v1_context->pgtable_cpu,
40 		    v1_context->pgtable_dma);
41 
42 	context->global->v1.shared_context = NULL;
43 
44 	kfree(v1_context);
45 }
46 
47 static int etnaviv_iommuv1_map(struct etnaviv_iommu_context *context,
48 			       unsigned long iova, phys_addr_t paddr,
49 			       size_t size, int prot)
50 {
51 	struct etnaviv_iommuv1_context *v1_context = to_v1_context(context);
52 	unsigned int index = (iova - GPU_MEM_START) / SZ_4K;
53 
54 	if (size != SZ_4K)
55 		return -EINVAL;
56 
57 	v1_context->pgtable_cpu[index] = paddr;
58 
59 	return 0;
60 }
61 
62 static size_t etnaviv_iommuv1_unmap(struct etnaviv_iommu_context *context,
63 	unsigned long iova, size_t size)
64 {
65 	struct etnaviv_iommuv1_context *v1_context = to_v1_context(context);
66 	unsigned int index = (iova - GPU_MEM_START) / SZ_4K;
67 
68 	if (size != SZ_4K)
69 		return -EINVAL;
70 
71 	v1_context->pgtable_cpu[index] = context->global->bad_page_dma;
72 
73 	return SZ_4K;
74 }
75 
76 static size_t etnaviv_iommuv1_dump_size(struct etnaviv_iommu_context *context)
77 {
78 	return PT_SIZE;
79 }
80 
81 static void etnaviv_iommuv1_dump(struct etnaviv_iommu_context *context,
82 				 void *buf)
83 {
84 	struct etnaviv_iommuv1_context *v1_context = to_v1_context(context);
85 
86 	memcpy(buf, v1_context->pgtable_cpu, PT_SIZE);
87 }
88 
89 static void etnaviv_iommuv1_restore(struct etnaviv_gpu *gpu,
90 			     struct etnaviv_iommu_context *context)
91 {
92 	struct etnaviv_iommuv1_context *v1_context = to_v1_context(context);
93 	u32 pgtable;
94 
95 	if (gpu->mmu_context)
96 		etnaviv_iommu_context_put(gpu->mmu_context);
97 	gpu->mmu_context = etnaviv_iommu_context_get(context);
98 
99 	/* set base addresses */
100 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_RA, context->global->memory_base);
101 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_FE, context->global->memory_base);
102 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_TX, context->global->memory_base);
103 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_PEZ, context->global->memory_base);
104 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_PE, context->global->memory_base);
105 
106 	/* set page table address in MC */
107 	pgtable = (u32)v1_context->pgtable_dma;
108 
109 	gpu_write(gpu, VIVS_MC_MMU_FE_PAGE_TABLE, pgtable);
110 	gpu_write(gpu, VIVS_MC_MMU_TX_PAGE_TABLE, pgtable);
111 	gpu_write(gpu, VIVS_MC_MMU_PE_PAGE_TABLE, pgtable);
112 	gpu_write(gpu, VIVS_MC_MMU_PEZ_PAGE_TABLE, pgtable);
113 	gpu_write(gpu, VIVS_MC_MMU_RA_PAGE_TABLE, pgtable);
114 }
115 
116 
117 const struct etnaviv_iommu_ops etnaviv_iommuv1_ops = {
118 	.free = etnaviv_iommuv1_free,
119 	.map = etnaviv_iommuv1_map,
120 	.unmap = etnaviv_iommuv1_unmap,
121 	.dump_size = etnaviv_iommuv1_dump_size,
122 	.dump = etnaviv_iommuv1_dump,
123 	.restore = etnaviv_iommuv1_restore,
124 };
125 
126 struct etnaviv_iommu_context *
127 etnaviv_iommuv1_context_alloc(struct etnaviv_iommu_global *global)
128 {
129 	struct etnaviv_iommuv1_context *v1_context;
130 	struct etnaviv_iommu_context *context;
131 
132 	mutex_lock(&global->lock);
133 
134 	/*
135 	 * MMUv1 does not support switching between different contexts without
136 	 * a stop the world operation, so we only support a single shared
137 	 * context with this version.
138 	 */
139 	if (global->v1.shared_context) {
140 		context = global->v1.shared_context;
141 		etnaviv_iommu_context_get(context);
142 		mutex_unlock(&global->lock);
143 		return context;
144 	}
145 
146 	v1_context = kzalloc(sizeof(*v1_context), GFP_KERNEL);
147 	if (!v1_context) {
148 		mutex_unlock(&global->lock);
149 		return NULL;
150 	}
151 
152 	v1_context->pgtable_cpu = dma_alloc_wc(global->dev, PT_SIZE,
153 					       &v1_context->pgtable_dma,
154 					       GFP_KERNEL);
155 	if (!v1_context->pgtable_cpu)
156 		goto out_free;
157 
158 	memset32(v1_context->pgtable_cpu, global->bad_page_dma, PT_ENTRIES);
159 
160 	context = &v1_context->base;
161 	context->global = global;
162 	kref_init(&context->refcount);
163 	mutex_init(&context->lock);
164 	INIT_LIST_HEAD(&context->mappings);
165 	drm_mm_init(&context->mm, GPU_MEM_START, PT_ENTRIES * SZ_4K);
166 	context->global->v1.shared_context = context;
167 
168 	mutex_unlock(&global->lock);
169 
170 	return context;
171 
172 out_free:
173 	mutex_unlock(&global->lock);
174 	kfree(v1_context);
175 	return NULL;
176 }
177