drivers/gpu/drm/exynos/exynos_drm_buf.c

   1 /* exynos_drm_buf.c
   2  *
   3  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
   4  * Author: Inki Dae <inki.dae@samsung.com>
   5  *
   6  * This program is free software; you can redistribute  it and/or modify it
   7  * under  the terms of  the GNU General  Public License as published by the
   8  * Free Software Foundation;  either version 2 of the  License, or (at your
   9  * option) any later version.
  10  */
  11
  12 #include <drm/drmP.h>
  13 #include <drm/exynos_drm.h>
  14
  15 #include "exynos_drm_drv.h"
  16 #include "exynos_drm_gem.h"
  17 #include "exynos_drm_buf.h"
  18 #include "exynos_drm_iommu.h"
  19
  20 static int lowlevel_buffer_allocate(struct drm_device *dev,
  21                 unsigned int flags, struct exynos_drm_gem_buf *buf)
  22 {
  23         int ret = 0;
  24         enum dma_attr attr;
  25         unsigned int nr_pages;
  26
  27         DRM_DEBUG_KMS("%s\n", __FILE__);
  28
  29         if (buf->dma_addr) {
  30                 DRM_DEBUG_KMS("already allocated.\n");
  31                 return 0;
  32         }
  33
  34         init_dma_attrs(&buf->dma_attrs);
  35
  36         /*
  37          * if EXYNOS_BO_CONTIG, fully physically contiguous memory
  38          * region will be allocated else physically contiguous
  39          * as possible.
  40          */
  41         if (!(flags & EXYNOS_BO_NONCONTIG))
  42                 dma_set_attr(DMA_ATTR_FORCE_CONTIGUOUS, &buf->dma_attrs);
  43
  44         /*
  45          * if EXYNOS_BO_WC or EXYNOS_BO_NONCACHABLE, writecombine mapping
  46          * else cachable mapping.
  47          */
  48         if (flags & EXYNOS_BO_WC || !(flags & EXYNOS_BO_CACHABLE))
  49                 attr = DMA_ATTR_WRITE_COMBINE;
  50         else
  51                 attr = DMA_ATTR_NON_CONSISTENT;
  52
  53         dma_set_attr(attr, &buf->dma_attrs);
  54         dma_set_attr(DMA_ATTR_NO_KERNEL_MAPPING, &buf->dma_attrs);
  55
  56         nr_pages = buf->size >> PAGE_SHIFT;
  57
  58         if (!is_drm_iommu_supported(dev)) {
  59                 dma_addr_t start_addr;
  60                 unsigned int i = 0;
  61
  62                 buf->pages = kzalloc(sizeof(struct page) * nr_pages,
  63                                         GFP_KERNEL);
  64                 if (!buf->pages) {
  65                         DRM_ERROR("failed to allocate pages.\n");
  66                         return -ENOMEM;
  67                 }
  68
  69                 buf->kvaddr = dma_alloc_attrs(dev->dev, buf->size,
  70                                         &buf->dma_addr, GFP_KERNEL,
  71                                         &buf->dma_attrs);
  72                 if (!buf->kvaddr) {
  73                         DRM_ERROR("failed to allocate buffer.\n");
  74                         kfree(buf->pages);
  75                         return -ENOMEM;
  76                 }
  77
  78                 start_addr = buf->dma_addr;
  79                 while (i < nr_pages) {
  80                         buf->pages[i] = phys_to_page(start_addr);
  81                         start_addr += PAGE_SIZE;
  82                         i++;
  83                 }
  84         } else {
  85
  86                 buf->pages = dma_alloc_attrs(dev->dev, buf->size,
  87                                         &buf->dma_addr, GFP_KERNEL,
  88                                         &buf->dma_attrs);
  89                 if (!buf->pages) {
  90                         DRM_ERROR("failed to allocate buffer.\n");
  91                         return -ENOMEM;
  92                 }
  93         }
  94
  95         buf->sgt = drm_prime_pages_to_sg(buf->pages, nr_pages);
  96         if (!buf->sgt) {
  97                 DRM_ERROR("failed to get sg table.\n");
  98                 ret = -ENOMEM;
  99                 goto err_free_attrs;
 100         }
 101
 102         DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
 103                         (unsigned long)buf->dma_addr,
 104                         buf->size);
 105
 106         return ret;
 107
 108 err_free_attrs:
 109         dma_free_attrs(dev->dev, buf->size, buf->pages,
 110                         (dma_addr_t)buf->dma_addr, &buf->dma_attrs);
 111         buf->dma_addr = (dma_addr_t)NULL;
 112
 113         if (!is_drm_iommu_supported(dev))
 114                 kfree(buf->pages);
 115
 116         return ret;
 117 }
 118
 119 static void lowlevel_buffer_deallocate(struct drm_device *dev,
 120                 unsigned int flags, struct exynos_drm_gem_buf *buf)
 121 {
 122         DRM_DEBUG_KMS("%s.\n", __FILE__);
 123
 124         if (!buf->dma_addr) {
 125                 DRM_DEBUG_KMS("dma_addr is invalid.\n");
 126                 return;
 127         }
 128
 129         DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
 130                         (unsigned long)buf->dma_addr,
 131                         buf->size);
 132
 133         sg_free_table(buf->sgt);
 134
 135         kfree(buf->sgt);
 136         buf->sgt = NULL;
 137
 138         if (!is_drm_iommu_supported(dev)) {
 139                 dma_free_attrs(dev->dev, buf->size, buf->kvaddr,
 140                                 (dma_addr_t)buf->dma_addr, &buf->dma_attrs);
 141                 kfree(buf->pages);
 142         } else
 143                 dma_free_attrs(dev->dev, buf->size, buf->pages,
 144                                 (dma_addr_t)buf->dma_addr, &buf->dma_attrs);
 145
 146         buf->dma_addr = (dma_addr_t)NULL;
 147 }
 148
 149 struct exynos_drm_gem_buf *exynos_drm_init_buf(struct drm_device *dev,
 150                                                 unsigned int size)
 151 {
 152         struct exynos_drm_gem_buf *buffer;
 153
 154         DRM_DEBUG_KMS("%s.\n", __FILE__);
 155         DRM_DEBUG_KMS("desired size = 0x%x\n", size);
 156
 157         buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
 158         if (!buffer) {
 159                 DRM_ERROR("failed to allocate exynos_drm_gem_buf.\n");
 160                 return NULL;
 161         }
 162
 163         buffer->size = size;
 164         return buffer;
 165 }
 166
 167 void exynos_drm_fini_buf(struct drm_device *dev,
 168                                 struct exynos_drm_gem_buf *buffer)
 169 {
 170         DRM_DEBUG_KMS("%s.\n", __FILE__);
 171
 172         if (!buffer) {
 173                 DRM_DEBUG_KMS("buffer is null.\n");
 174                 return;
 175         }
 176
 177         kfree(buffer);
 178         buffer = NULL;
 179 }
 180
 181 int exynos_drm_alloc_buf(struct drm_device *dev,
 182                 struct exynos_drm_gem_buf *buf, unsigned int flags)
 183 {
 184
 185         /*
 186          * allocate memory region and set the memory information
 187          * to vaddr and dma_addr of a buffer object.
 188          */
 189         if (lowlevel_buffer_allocate(dev, flags, buf) < 0)
 190                 return -ENOMEM;
 191
 192         return 0;
 193 }
 194
 195 void exynos_drm_free_buf(struct drm_device *dev,
 196                 unsigned int flags, struct exynos_drm_gem_buf *buffer)
 197 {
 198
 199         lowlevel_buffer_deallocate(dev, flags, buffer);
 200 }