sdm: add support for windowed display

- window display feature is displaying framebuffer
  content in a given rectangle on panel.
- fill remaining area with default color i.e. black.
- inform SF with reduced display size but SDM
  will see the mixer resolution is equal to panel.
- window rectangle can be set using below property
     vendor.display.window_rect = 250,250,250,250

CRs-Fixed: 2200594
Change-Id: Ib4cd4ccd6839370b568dbcdbadcdd81cfae88af9

composer/hwc_display.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2019, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2014-2020, The Linux Foundation. All rights reserved.
  * Not a Contribution.
  *
  * Copyright 2015 The Android Open Source Project
@@ -464,6 +464,12 @@ HWCDisplay::HWCDisplay(CoreInterface *core_intf, BufferAllocator *buffer_allocat
 int HWCDisplay::Init() {
   DisplayError error = kErrorNone;
 
+  Debug::GetWindowRect(&window_rect_.left, &window_rect_.top,
+                                 &window_rect_.right, &window_rect_.bottom);
+
+  DLOGI("Window rect : [%f %f %f %f]", window_rect_.left, window_rect_.top,
+         window_rect_.right, window_rect_.bottom);
+
   HWCDebugHandler::Get()->GetProperty(ENABLE_NULL_DISPLAY_PROP, &null_display_mode_);
   HWCDebugHandler::Get()->GetProperty(ENABLE_ASYNC_POWERMODE, &async_power_mode_);
 
@@ -1065,6 +1071,14 @@ HWC2::Error HWCDisplay::GetDisplayAttribute(hwc2_config_t config, HWC2::Attribut
   }
 
   DisplayConfigVariableInfo variable_config = variable_config_map_.at(config);
+
+  variable_config.x_pixels -= UINT32(window_rect_.right + window_rect_.left);
+  variable_config.y_pixels -= UINT32(window_rect_.bottom + window_rect_.top);
+  if (variable_config.x_pixels <= 0 || variable_config.y_pixels <= 0) {
+    DLOGE("window rects are not within the supported range");
+    return HWC2::Error::BadDisplay;
+  }
+
   switch (attribute) {
     case HWC2::Attribute::VsyncPeriod:
       *out_value = INT32(variable_config.vsync_period_ns);
@@ -1873,6 +1887,19 @@ int HWCDisplay::SetFrameBufferConfig(uint32_t x_pixels, uint32_t y_pixels) {
     return -EINVAL;
   }
 
+  // Reduce the src_rect and dst_rect as per FBT config.
+  // SF sending reduced FBT but here the src_rect is equal to mixer which is
+  // higher than allocated buffer of FBT.
+  if (windowed_display_) {
+    x_pixels -= UINT32(window_rect_.right + window_rect_.left);
+    y_pixels -= UINT32(window_rect_.bottom + window_rect_.top);
+  }
+
+  if (x_pixels <= 0 || y_pixels <= 0) {
+    DLOGE("window rects are not within the supported range");
+    return -EINVAL;
+  }
+
   // Create rects to represent the new source and destination crops
   LayerRect crop = LayerRect(0, 0, FLOAT(x_pixels), FLOAT(y_pixels));
   hwc_rect_t scaled_display_frame = {0, 0, INT(x_pixels), INT(y_pixels)};
@@ -1894,6 +1921,11 @@ int HWCDisplay::SetFrameBufferResolution(uint32_t x_pixels, uint32_t y_pixels) {
     return error;
   }
 
+  if (windowed_display_) {
+    x_pixels -= UINT32(window_rect_.right + window_rect_.left);
+    y_pixels -= UINT32(window_rect_.bottom + window_rect_.top);
+    windowed_display_ = false;
+  }
   auto client_target_layer = client_target_->GetSDMLayer();
 
   int aligned_width;

composer/hwc_display.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2019, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2014-2020, The Linux Foundation. All rights reserved.
  * Not a Contribution.
  *
  * Copyright 2015 The Android Open Source Project
@@ -484,6 +484,8 @@ class HWCDisplay : public DisplayEventHandler {
   bool pending_config_ = false;
   bool has_client_composition_ = false;
   HWCBufferSyncHandler buffer_sync_handler_ = {};
+  LayerRect window_rect_ = {};
+  bool windowed_display_ = true;
 
  private:
   void DumpInputBuffers(void);

include/display_properties.h

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2018-2019, The Linux Foundation. All rights reserved.
+* Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
@@ -129,6 +129,7 @@
 // Add all persist.vendor.display.properties above
 
 #define ZERO_SWAP_INTERVAL                   "vendor.debug.egl.swapinterval"
+#define WINDOW_RECT_PROP                     DISPLAY_PROP("window_rect")
 
 // Add all other.properties above
 // End of property

sdm/include/utils/debug.h

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2014 - 2018, The Linux Foundation. All rights reserved.
+* Copyright (c) 2014 - 2018, 2020 The Linux Foundation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
@@ -60,6 +60,7 @@ class Debug {
   static bool IsPartialSplitDisabled();
   static bool IsSrcSplitPreferred();
   static DisplayError GetMixerResolution(uint32_t *width, uint32_t *height);
+  static DisplayError GetWindowRect(float *left, float *top, float *right, float *bottom);
   static DisplayError GetReducedConfig(uint32_t *num_vig_pipes, uint32_t *num_dma_pipes);
   static int GetExtMaxlayers();
   static DisplayError GetProperty(const char *property_name, char *value);

sdm/libs/utils/debug.cpp

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2014 - 2018, The Linux Foundation. All rights reserved.
+* Copyright (c) 2014 - 2018, 2020 The Linux Foundation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
@@ -183,6 +183,30 @@ DisplayError Debug::GetMixerResolution(uint32_t *width, uint32_t *height) {
   return kErrorNone;
 }
 
+DisplayError Debug::GetWindowRect(float *left, float *top, float *right, float *bottom) {
+  char value[64] = {};
+
+  int error = DebugHandler::Get()->GetProperty(WINDOW_RECT_PROP, value);
+  if (error != 0) {
+    return kErrorUndefined;
+  }
+
+  std::string str(value);
+  *left = FLOAT(stof(str));
+  str = (str.substr(str.find(',') + 1));
+  *top = FLOAT(stof(str));
+  str = (str.substr(str.find(',') + 1));
+  *right = FLOAT(stof(str));
+  str = (str.substr(str.find(',') + 1));
+  *bottom = FLOAT(stof(str));
+
+  if (*left < 0 || *top < 0 || *right < 0 || *bottom < 0) {
+    *left = *top = *right = *bottom = 0;
+  }
+
+  return kErrorNone;
+}
+
 DisplayError Debug::GetReducedConfig(uint32_t *num_vig_pipes, uint32_t *num_dma_pipes) {
   char value[64] = {};