libkms++/dumbframebuffer.cpp

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