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 	/* set base addresses */
96 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_RA, context->global->memory_base);
97 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_FE, context->global->memory_base);
98 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_TX, context->global->memory_base);
99 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_PEZ, context->global->memory_base);
100 	gpu_write(gpu, VIVS_MC_MEMORY_BASE_ADDR_PE, context->global->memory_base);
101 
102 	/* set page table address in MC */
103 	pgtable = (u32)v1_context->pgtable_dma;
104 
105 	gpu_write(gpu, VIVS_MC_MMU_FE_PAGE_TABLE, pgtable);
106 	gpu_write(gpu, VIVS_MC_MMU_TX_PAGE_TABLE, pgtable);
107 	gpu_write(gpu, VIVS_MC_MMU_PE_PAGE_TABLE, pgtable);
108 	gpu_write(gpu, VIVS_MC_MMU_PEZ_PAGE_TABLE, pgtable);
109 	gpu_write(gpu, VIVS_MC_MMU_RA_PAGE_TABLE, pgtable);
110 }
111 
112 
113 const struct etnaviv_iommu_ops etnaviv_iommuv1_ops = {
114 	.free = etnaviv_iommuv1_free,
115 	.map = etnaviv_iommuv1_map,
116 	.unmap = etnaviv_iommuv1_unmap,
117 	.dump_size = etnaviv_iommuv1_dump_size,
118 	.dump = etnaviv_iommuv1_dump,
119 	.restore = etnaviv_iommuv1_restore,
120 };
121 
122 struct etnaviv_iommu_context *
123 etnaviv_iommuv1_context_alloc(struct etnaviv_iommu_global *global)
124 {
125 	struct etnaviv_iommuv1_context *v1_context;
126 	struct etnaviv_iommu_context *context;
127 
128 	mutex_lock(&global->lock);
129 
130 	/*
131 	 * MMUv1 does not support switching between different contexts without
132 	 * a stop the world operation, so we only support a single shared
133 	 * context with this version.
134 	 */
135 	if (global->v1.shared_context) {
136 		context = global->v1.shared_context;
137 		etnaviv_iommu_context_get(context);
138 		mutex_unlock(&global->lock);
139 		return context;
140 	}
141 
142 	v1_context = kzalloc(sizeof(*v1_context), GFP_KERNEL);
143 	if (!v1_context) {
144 		mutex_unlock(&global->lock);
145 		return NULL;
146 	}
147 
148 	v1_context->pgtable_cpu = dma_alloc_wc(global->dev, PT_SIZE,
149 					       &v1_context->pgtable_dma,
150 					       GFP_KERNEL);
151 	if (!v1_context->pgtable_cpu)
152 		goto out_free;
153 
154 	memset32(v1_context->pgtable_cpu, global->bad_page_dma, PT_ENTRIES);
155 
156 	context = &v1_context->base;
157 	context->global = global;
158 	kref_init(&context->refcount);
159 	mutex_init(&context->lock);
160 	INIT_LIST_HEAD(&context->mappings);
161 	drm_mm_init(&context->mm, GPU_MEM_START, PT_ENTRIES * SZ_4K);
162 	context->global->v1.shared_context = context;
163 
164 	mutex_unlock(&global->lock);
165 
166 	return context;
167 
168 out_free:
169 	mutex_unlock(&global->lock);
170 	kfree(v1_context);
171 	return NULL;
172 }
173