kms++/src/dumbframebuffer.cpp

   1
   2 #include <cstring>
   3 #include <cerrno>
   4 #include <stdexcept>
   5 #include <sys/mman.h>
   6 #include <xf86drm.h>
   7 #include <xf86drmMode.h>
   8 #include <fcntl.h>
   9 #include <unistd.h>
  10 #include <drm_fourcc.h>
  11 #include <drm.h>
  12 #include <drm_mode.h>
  13
  14 #include <kms++/kms++.h>
  15
  16 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
  17
  18 using namespace std;
  19
  20 namespace kms
  21 {
  22
  23 DumbFramebuffer::DumbFramebuffer(Card &card, uint32_t width, uint32_t height, const string& fourcc)
  24         :DumbFramebuffer(card, width, height, FourCCToPixelFormat(fourcc))
  25 {
  26 }
  27
  28 DumbFramebuffer::DumbFramebuffer(Card& card, uint32_t width, uint32_t height, PixelFormat format)
  29         :Framebuffer(card, width, height), m_format(format)
  30 {
  31         Create();
  32 }
  33
  34 DumbFramebuffer::~DumbFramebuffer()
  35 {
  36         Destroy();
  37 }
  38
  39 void DumbFramebuffer::Create()
  40 {
  41         int r;
  42
  43         const PixelFormatInfo& format_info = get_pixel_format_info(m_format);
  44
  45         m_num_planes = format_info.num_planes;
  46
  47         for (int i = 0; i < format_info.num_planes; ++i) {
  48                 const PixelFormatPlaneInfo& pi = format_info.planes[i];
  49                 FramebufferPlane& plane = m_planes[i];
  50
  51                 /* create dumb buffer */
  52                 struct drm_mode_create_dumb creq = drm_mode_create_dumb();
  53                 creq.width = width();
  54                 creq.height = height() / pi.ysub;
  55                 creq.bpp = pi.bitspp;
  56                 r = drmIoctl(card().fd(), DRM_IOCTL_MODE_CREATE_DUMB, &creq);
  57                 if (r)
  58                         throw invalid_argument(string("DRM_IOCTL_MODE_CREATE_DUMB failed: ") + strerror(errno));
  59
  60                 plane.handle = creq.handle;
  61                 plane.stride = creq.pitch;
  62                 plane.size = creq.height * creq.pitch;
  63                 plane.offset = 0;
  64                 plane.map = 0;
  65                 plane.prime_fd = -1;
  66         }
  67
  68         /* create framebuffer object for the dumb-buffer */
  69         uint32_t bo_handles[4] = { m_planes[0].handle, m_planes[1].handle };
  70         uint32_t pitches[4] = { m_planes[0].stride, m_planes[1].stride };
  71         uint32_t offsets[4] = {  m_planes[0].offset, m_planes[1].offset };
  72         uint32_t id;
  73         r = drmModeAddFB2(card().fd(), width(), height(), (uint32_t)format(),
  74                           bo_handles, pitches, offsets, &id, 0);
  75         if (r)
  76                 throw invalid_argument(string("drmModeAddFB2 failed: ") + strerror(errno));
  77
  78         set_id(id);
  79 }
  80
  81 void DumbFramebuffer::Destroy()
  82 {
  83         /* delete framebuffer */
  84         drmModeRmFB(card().fd(), id());
  85
  86         for (uint i = 0; i < m_num_planes; ++i) {
  87                 FramebufferPlane& plane = m_planes[i];
  88
  89                 /* unmap buffer */
  90                 if (plane.map)
  91                         munmap(plane.map, plane.size);
  92
  93                 /* delete dumb buffer */
  94                 struct drm_mode_destroy_dumb dreq = drm_mode_destroy_dumb();
  95                 dreq.handle = plane.handle;
  96                 drmIoctl(card().fd(), DRM_IOCTL_MODE_DESTROY_DUMB, &dreq);
  97                 if (plane.prime_fd >= 0)
  98                         ::close(plane.prime_fd);
  99         }
 100 }
 101
 102 uint8_t* DumbFramebuffer::map(unsigned plane)
 103 {
 104         FramebufferPlane& p = m_planes[plane];
 105
 106         if (p.map)
 107                 return p.map;
 108
 109         /* prepare buffer for memory mapping */
 110         struct drm_mode_map_dumb mreq = drm_mode_map_dumb();
 111         mreq.handle = p.handle;
 112         int r = drmIoctl(card().fd(), DRM_IOCTL_MODE_MAP_DUMB, &mreq);
 113         if (r)
 114                 throw invalid_argument(string("DRM_IOCTL_MODE_MAP_DUMB failed: ") + strerror(errno));
 115
 116         /* perform actual memory mapping */
 117         p.map = (uint8_t *)mmap(0, p.size, PROT_READ | PROT_WRITE, MAP_SHARED,
 118                                           card().fd(), mreq.offset);
 119         if (p.map == MAP_FAILED)
 120                 throw invalid_argument(string("mmap failed: ") + strerror(errno));
 121
 122         return p.map;
 123 }
 124
 125 int DumbFramebuffer::prime_fd(unsigned int plane)
 126 {
 127         if (m_planes[plane].prime_fd >= 0)
 128                 return m_planes[plane].prime_fd;
 129
 130         int r = drmPrimeHandleToFD(card().fd(), m_planes[plane].handle,
 131                                    DRM_CLOEXEC | O_RDWR, &m_planes[plane].prime_fd);
 132         if (r)
 133                 throw std::runtime_error("drmPrimeHandleToFD failed");
 134
 135         return m_planes[plane].prime_fd;
 136 }
 137
 138 }