drivers/gpu/drm/etnaviv/etnaviv_iommu.c

   1 /*
   2  * Copyright (C) 2014 Christian Gmeiner <christian.gmeiner@gmail.com>
   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/iommu.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/sizes.h>
  20 #include <linux/slab.h>
  21 #include <linux/dma-mapping.h>
  22 #include <linux/bitops.h>
  23
  24 #include "etnaviv_gpu.h"
  25 #include "etnaviv_mmu.h"
  26 #include "etnaviv_iommu.h"
  27 #include "state_hi.xml.h"
  28
  29 #define PT_SIZE         SZ_2M
  30 #define PT_ENTRIES      (PT_SIZE / sizeof(u32))
  31
  32 #define GPU_MEM_START   0x80000000
  33
  34 struct etnaviv_iommu_domain_pgtable {
  35         u32 *pgtable;
  36         dma_addr_t paddr;
  37 };
  38
  39 struct etnaviv_iommu_domain {
  40         struct iommu_domain domain;
  41         struct device *dev;
  42         void *bad_page_cpu;
  43         dma_addr_t bad_page_dma;
  44         struct etnaviv_iommu_domain_pgtable pgtable;
  45         spinlock_t map_lock;
  46 };
  47
  48 static struct etnaviv_iommu_domain *to_etnaviv_domain(struct iommu_domain *domain)
  49 {
  50         return container_of(domain, struct etnaviv_iommu_domain, domain);
  51 }
  52
  53 static int pgtable_alloc(struct etnaviv_iommu_domain_pgtable *pgtable,
  54                          size_t size)
  55 {
  56         pgtable->pgtable = dma_alloc_coherent(NULL, size, &pgtable->paddr, GFP_KERNEL);
  57         if (!pgtable->pgtable)
  58                 return -ENOMEM;
  59
  60         return 0;
  61 }
  62
  63 static void pgtable_free(struct etnaviv_iommu_domain_pgtable *pgtable,
  64                          size_t size)
  65 {
  66         dma_free_coherent(NULL, size, pgtable->pgtable, pgtable->paddr);
  67 }
  68
  69 static u32 pgtable_read(struct etnaviv_iommu_domain_pgtable *pgtable,
  70                            unsigned long iova)
  71 {
  72         /* calcuate index into page table */
  73         unsigned int index = (iova - GPU_MEM_START) / SZ_4K;
  74         phys_addr_t paddr;
  75
  76         paddr = pgtable->pgtable[index];
  77
  78         return paddr;
  79 }
  80
  81 static void pgtable_write(struct etnaviv_iommu_domain_pgtable *pgtable,
  82                           unsigned long iova, phys_addr_t paddr)
  83 {
  84         /* calcuate index into page table */
  85         unsigned int index = (iova - GPU_MEM_START) / SZ_4K;
  86
  87         pgtable->pgtable[index] = paddr;
  88 }
  89
  90 static int __etnaviv_iommu_init(struct etnaviv_iommu_domain *etnaviv_domain)
  91 {
  92         u32 *p;
  93         int ret, i;
  94
  95         etnaviv_domain->bad_page_cpu = dma_alloc_coherent(etnaviv_domain->dev,
  96                                                   SZ_4K,
  97                                                   &etnaviv_domain->bad_page_dma,
  98                                                   GFP_KERNEL);
  99         if (!etnaviv_domain->bad_page_cpu)
 100                 return -ENOMEM;
 101
 102         p = etnaviv_domain->bad_page_cpu;
 103         for (i = 0; i < SZ_4K / 4; i++)
 104                 *p++ = 0xdead55aa;
 105
 106         ret = pgtable_alloc(&etnaviv_domain->pgtable, PT_SIZE);
 107         if (ret < 0) {
 108                 dma_free_coherent(etnaviv_domain->dev, SZ_4K,
 109                                   etnaviv_domain->bad_page_cpu,
 110                                   etnaviv_domain->bad_page_dma);
 111                 return ret;
 112         }
 113
 114         for (i = 0; i < PT_ENTRIES; i++)
 115                 etnaviv_domain->pgtable.pgtable[i] =
 116                         etnaviv_domain->bad_page_dma;
 117
 118         spin_lock_init(&etnaviv_domain->map_lock);
 119
 120         return 0;
 121 }
 122
 123 static void etnaviv_domain_free(struct iommu_domain *domain)
 124 {
 125         struct etnaviv_iommu_domain *etnaviv_domain = to_etnaviv_domain(domain);
 126
 127         pgtable_free(&etnaviv_domain->pgtable, PT_SIZE);
 128
 129         dma_free_coherent(etnaviv_domain->dev, SZ_4K,
 130                           etnaviv_domain->bad_page_cpu,
 131                           etnaviv_domain->bad_page_dma);
 132
 133         kfree(etnaviv_domain);
 134 }
 135
 136 static int etnaviv_iommuv1_map(struct iommu_domain *domain, unsigned long iova,
 137            phys_addr_t paddr, size_t size, int prot)
 138 {
 139         struct etnaviv_iommu_domain *etnaviv_domain = to_etnaviv_domain(domain);
 140
 141         if (size != SZ_4K)
 142                 return -EINVAL;
 143
 144         spin_lock(&etnaviv_domain->map_lock);
 145         pgtable_write(&etnaviv_domain->pgtable, iova, paddr);
 146         spin_unlock(&etnaviv_domain->map_lock);
 147
 148         return 0;
 149 }
 150
 151 static size_t etnaviv_iommuv1_unmap(struct iommu_domain *domain,
 152         unsigned long iova, size_t size)
 153 {
 154         struct etnaviv_iommu_domain *etnaviv_domain = to_etnaviv_domain(domain);
 155
 156         if (size != SZ_4K)
 157                 return -EINVAL;
 158
 159         spin_lock(&etnaviv_domain->map_lock);
 160         pgtable_write(&etnaviv_domain->pgtable, iova,
 161                       etnaviv_domain->bad_page_dma);
 162         spin_unlock(&etnaviv_domain->map_lock);
 163
 164         return SZ_4K;
 165 }
 166
 167 static phys_addr_t etnaviv_iommu_iova_to_phys(struct iommu_domain *domain,
 168         dma_addr_t iova)
 169 {
 170         struct etnaviv_iommu_domain *etnaviv_domain = to_etnaviv_domain(domain);
 171
 172         return pgtable_read(&etnaviv_domain->pgtable, iova);
 173 }
 174
 175 static size_t etnaviv_iommuv1_dump_size(struct iommu_domain *domain)
 176 {
 177         return PT_SIZE;
 178 }
 179
 180 static void etnaviv_iommuv1_dump(struct iommu_domain *domain, void *buf)
 181 {
 182         struct etnaviv_iommu_domain *etnaviv_domain = to_etnaviv_domain(domain);
 183
 184         memcpy(buf, etnaviv_domain->pgtable.pgtable, PT_SIZE);
 185 }
 186
 187 static struct etnaviv_iommu_ops etnaviv_iommu_ops = {
 188         .ops = {
 189                 .domain_free = etnaviv_domain_free,
 190                 .map = etnaviv_iommuv1_map,
 191                 .unmap = etnaviv_iommuv1_unmap,
 192                 .iova_to_phys = etnaviv_iommu_iova_to_phys,
 193                 .pgsize_bitmap = SZ_4K,
 194         },
 195         .dump_size = etnaviv_iommuv1_dump_size,
 196         .dump = etnaviv_iommuv1_dump,
 197 };
 198
 199 void etnaviv_iommu_domain_restore(struct etnaviv_gpu *gpu,
 200         struct iommu_domain *domain)
 201 {
 202         struct etnaviv_iommu_domain *etnaviv_domain = to_etnaviv_domain(domain);
 203         u32 pgtable;
 204
 205         /* set page table address in MC */
 206         pgtable = (u32)etnaviv_domain->pgtable.paddr;
 207
 208         gpu_write(gpu, VIVS_MC_MMU_FE_PAGE_TABLE, pgtable);
 209         gpu_write(gpu, VIVS_MC_MMU_TX_PAGE_TABLE, pgtable);
 210         gpu_write(gpu, VIVS_MC_MMU_PE_PAGE_TABLE, pgtable);
 211         gpu_write(gpu, VIVS_MC_MMU_PEZ_PAGE_TABLE, pgtable);
 212         gpu_write(gpu, VIVS_MC_MMU_RA_PAGE_TABLE, pgtable);
 213 }
 214
 215 struct iommu_domain *etnaviv_iommu_domain_alloc(struct etnaviv_gpu *gpu)
 216 {
 217         struct etnaviv_iommu_domain *etnaviv_domain;
 218         int ret;
 219
 220         etnaviv_domain = kzalloc(sizeof(*etnaviv_domain), GFP_KERNEL);
 221         if (!etnaviv_domain)
 222                 return NULL;
 223
 224         etnaviv_domain->dev = gpu->dev;
 225
 226         etnaviv_domain->domain.type = __IOMMU_DOMAIN_PAGING;
 227         etnaviv_domain->domain.ops = &etnaviv_iommu_ops.ops;
 228         etnaviv_domain->domain.geometry.aperture_start = GPU_MEM_START;
 229         etnaviv_domain->domain.geometry.aperture_end = GPU_MEM_START + PT_ENTRIES * SZ_4K - 1;
 230
 231         ret = __etnaviv_iommu_init(etnaviv_domain);
 232         if (ret)
 233                 goto out_free;
 234
 235         return &etnaviv_domain->domain;
 236
 237 out_free:
 238         kfree(etnaviv_domain);
 239         return NULL;
 240 }