/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#define LOG_TAG "hwc-platform-nv"

#include "drmresources.h"
#include "platform.h"
#include "platformnv.h"

#include <cinttypes>
#include <stdatomic.h>
#include <drm/drm_fourcc.h>
#include <xf86drm.h>
#include <xf86drmMode.h>

#include <cutils/log.h>
#include <hardware/gralloc.h>

namespace android {

#ifdef USE_NVIDIA_IMPORTER
// static
Importer *Importer::CreateInstance(DrmResources *drm) {
  NvImporter *importer = new NvImporter(drm);
  if (!importer)
    return NULL;

  int ret = importer->Init();
  if (ret) {
    ALOGE("Failed to initialize the nv importer %d", ret);
    delete importer;
    return NULL;
  }
  return importer;
}
#endif

NvImporter::NvImporter(DrmResources *drm) : drm_(drm) {
}

NvImporter::~NvImporter() {
}

int NvImporter::Init() {
  int ret = hw_get_module(GRALLOC_HARDWARE_MODULE_ID,
                          (const hw_module_t **)&gralloc_);
  if (ret) {
    ALOGE("Failed to open gralloc module %d", ret);
    return ret;
  }

  if (strcasecmp(gralloc_->common.author, "NVIDIA"))
    ALOGW("Using non-NVIDIA gralloc module: %s/%s\n", gralloc_->common.name,
          gralloc_->common.author);

  return 0;
}

int NvImporter::ImportBuffer(buffer_handle_t handle, hwc_drm_bo_t *bo) {
  memset(bo, 0, sizeof(hwc_drm_bo_t));
  NvBuffer_t *buf = GrallocGetNvBuffer(handle);
  if (buf) {
    atomic_fetch_add(&buf->ref, 1);
    *bo = buf->bo;
    return 0;
  }

  buf = new NvBuffer_t();
  if (!buf) {
    ALOGE("Failed to allocate new NvBuffer_t");
    return -ENOMEM;
  }
  buf->bo.priv = buf;
  buf->importer = this;

  // We initialize the reference count to 2 since NvGralloc is still using this
  // buffer (will be cleared in the NvGrallocRelease), and the other
  // reference is for HWC (this ImportBuffer call).
  atomic_init(&buf->ref, 2);

  int ret = gralloc_->perform(gralloc_, GRALLOC_MODULE_PERFORM_DRM_IMPORT,
                              drm_->fd(), handle, &buf->bo);
  if (ret) {
    ALOGE("GRALLOC_MODULE_PERFORM_DRM_IMPORT failed %d", ret);
    delete buf;
    return ret;
  }

  ret = drmModeAddFB2(drm_->fd(), buf->bo.width, buf->bo.height, buf->bo.format,
                      buf->bo.gem_handles, buf->bo.pitches, buf->bo.offsets,
                      &buf->bo.fb_id, 0);
  if (ret) {
    ALOGE("Failed to add fb %d", ret);
    ReleaseBufferImpl(&buf->bo);
    delete buf;
    return ret;
  }

  ret = GrallocSetNvBuffer(handle, buf);
  if (ret) {
    /* This will happen is persist.tegra.gpu_mapping_cache is 0/off,
     * or if NV gralloc runs out of "priv slots" (currently 3 per buffer,
     * only one of which should be used by drm_hwcomposer). */
    ALOGE("Failed to register free callback for imported buffer %d", ret);
    ReleaseBufferImpl(&buf->bo);
    delete buf;
    return ret;
  }
  *bo = buf->bo;
  return 0;
}

int NvImporter::ReleaseBuffer(hwc_drm_bo_t *bo) {
  NvBuffer_t *buf = (NvBuffer_t *)bo->priv;
  if (!buf) {
    ALOGE("Freeing bo %" PRIu32 ", buf is NULL!", bo->fb_id);
    return 0;
  }
  if (atomic_fetch_sub(&buf->ref, 1) > 1)
    return 0;

  ReleaseBufferImpl(bo);
  delete buf;
  return 0;
}

// static
void NvImporter::NvGrallocRelease(void *nv_buffer) {
  NvBuffer_t *buf = (NvBuffer *)nv_buffer;
  buf->importer->ReleaseBuffer(&buf->bo);
}

void NvImporter::ReleaseBufferImpl(hwc_drm_bo_t *bo) {
  if (bo->fb_id) {
    int ret = drmModeRmFB(drm_->fd(), bo->fb_id);
    if (ret)
      ALOGE("Failed to rm fb %d", ret);
  }

  struct drm_gem_close gem_close;
  memset(&gem_close, 0, sizeof(gem_close));
  int num_gem_handles = sizeof(bo->gem_handles) / sizeof(bo->gem_handles[0]);
  for (int i = 0; i < num_gem_handles; i++) {
    if (!bo->gem_handles[i])
      continue;

    gem_close.handle = bo->gem_handles[i];
    int ret = drmIoctl(drm_->fd(), DRM_IOCTL_GEM_CLOSE, &gem_close);
    if (ret) {
      ALOGE("Failed to close gem handle %d %d", i, ret);
    } else {
      /* Clear any duplicate gem handle as well but don't close again */
      for (int j = i + 1; j < num_gem_handles; j++)
        if (bo->gem_handles[j] == bo->gem_handles[i])
          bo->gem_handles[j] = 0;
      bo->gem_handles[i] = 0;
    }
  }
}

NvImporter::NvBuffer_t *NvImporter::GrallocGetNvBuffer(buffer_handle_t handle) {
  void *priv = NULL;
  int ret =
      gralloc_->perform(gralloc_, GRALLOC_MODULE_PERFORM_GET_IMPORTER_PRIVATE,
                        handle, NvGrallocRelease, &priv);
  return ret ? NULL : (NvBuffer_t *)priv;
}

int NvImporter::GrallocSetNvBuffer(buffer_handle_t handle, NvBuffer_t *buf) {
  return gralloc_->perform(gralloc_,
                           GRALLOC_MODULE_PERFORM_SET_IMPORTER_PRIVATE, handle,
                           NvGrallocRelease, buf);
}

#ifdef USE_NVIDIA_IMPORTER
// static
std::unique_ptr<Planner> Planner::CreateInstance(DrmResources *) {
  std::unique_ptr<Planner> planner(new Planner);
  planner->AddStage<PlanStageNvLimits>();
  planner->AddStage<PlanStageProtectedRotated>();
  planner->AddStage<PlanStageProtected>();
  planner->AddStage<PlanStagePrecomp>();
  planner->AddStage<PlanStageGreedy>();
  return planner;
}
#endif

static DrmPlane *GetCrtcPrimaryPlane(DrmCrtc *crtc,
                                     std::vector<DrmPlane *> *planes) {
  for (auto i = planes->begin(); i != planes->end(); ++i) {
    if ((*i)->GetCrtcSupported(*crtc)) {
      DrmPlane *plane = *i;
      planes->erase(i);
      return plane;
    }
  }
  return NULL;
}

int PlanStageProtectedRotated::ProvisionPlanes(
    std::vector<DrmCompositionPlane> *composition,
    std::map<size_t, DrmHwcLayer *> &layers, DrmCrtc *crtc,
    std::vector<DrmPlane *> *planes) {
  int ret;
  int protected_zorder = -1;
  for (auto i = layers.begin(); i != layers.end();) {
    if (!i->second->protected_usage() || !i->second->transform) {
      ++i;
      continue;
    }

    auto primary_iter = planes->begin();
    for (; primary_iter != planes->end(); ++primary_iter) {
      if ((*primary_iter)->type() == DRM_PLANE_TYPE_PRIMARY)
        break;
    }

    // We cheat a little here. Since there can only be one primary plane per
    // crtc, we know we'll only hit this case once. So we blindly insert the
    // protected content at the beginning of the composition, knowing this path
    // won't be taken a second time during the loop.
    if (primary_iter != planes->end()) {
      composition->emplace(composition->begin(),
                           DrmCompositionPlane::Type::kLayer, *primary_iter,
                           crtc, i->first);
      planes->erase(primary_iter);
      protected_zorder = i->first;
    } else {
      ALOGE("Could not provision primary plane for protected/rotated layer");
    }
    i = layers.erase(i);
  }

  if (protected_zorder == -1)
    return 0;

  // Add any layers below the protected content to the precomposition since we
  // need to punch a hole through them.
  for (auto i = layers.begin(); i != layers.end();) {
    // Skip layers above the z-order of the protected content
    if (i->first > static_cast<size_t>(protected_zorder)) {
      ++i;
      continue;
    }

    // If there's no precomp layer already queued, queue one now.
    DrmCompositionPlane *precomp = GetPrecomp(composition);
    if (precomp) {
      precomp->source_layers().emplace_back(i->first);
    } else {
      if (planes->size()) {
        DrmPlane *precomp_plane = planes->back();
        planes->pop_back();
        composition->emplace_back(DrmCompositionPlane::Type::kPrecomp,
                                  precomp_plane, crtc, i->first);
      } else {
        ALOGE("Not enough planes to reserve for precomp fb");
      }
    }
    i = layers.erase(i);
  }
  return 0;
}

bool PlanStageNvLimits::CheckLayer(DrmHwcLayer *layer) {
    auto src_w = layer->source_crop.width();
    auto src_h = layer->source_crop.height();
    auto dst_w = layer->display_frame.width();
    auto dst_h = layer->display_frame.height();
    int h_limit = 4;
    int v_limit;

    switch (layer->buffer->format) {
      case DRM_FORMAT_YVU420:
      case DRM_FORMAT_BGR565:
        v_limit = 4;
        break;
      default:
        v_limit = 2;
        break;
    }

    if (layer->transform &
        (DrmHwcTransform::kRotate90 | DrmHwcTransform::kRotate270))
      std::swap(dst_w, dst_h);

    // check for max supported down scaling
    if (((src_w / dst_w) > h_limit) || ((src_h / dst_h) > v_limit))
      return false;

    return true;
}

int PlanStageNvLimits::ProvisionPlanes(
    std::vector<DrmCompositionPlane> *composition,
    std::map<size_t, DrmHwcLayer *> &layers, DrmCrtc *crtc,
    std::vector<DrmPlane *> *planes) {
  int ret;

  for (auto i = layers.begin(); i != layers.end();) {
    // Skip layer if supported
    if (CheckLayer(i->second)) {
      i++;
      continue;
    }

    if (i->second->protected_usage()) {
      // Drop the layer if unsupported and protected, this will just display
      // black in the area of this layer but it's better than failing miserably
      i = layers.erase(i);
      continue;
    }

    // If there's no precomp layer already queued, queue one now.
    DrmCompositionPlane *precomp = GetPrecomp(composition);
    if (precomp) {
      precomp->source_layers().emplace_back(i->first);
    } else if (!planes->empty()) {
      DrmPlane *precomp_plane = planes->back();
      planes->pop_back();
      composition->emplace_back(DrmCompositionPlane::Type::kPrecomp,
                                precomp_plane, crtc, i->first);
    } else {
      ALOGE("Not enough planes to reserve for precomp fb");
    }
    i = layers.erase(i);
  }

  return 0;
}
}