text: // SPDX-License-Identifier: GPL-2.0-or-later
  /*
   */
  
  #include "bochs.h"
  #include <drm/drm_atomic_helper.h>
  #include <drm/drm_plane_helper.h>
  #include <drm/drm_atomic_uapi.h>
  #include <drm/drm_gem_framebuffer_helper.h>
  #include <drm/drm_probe_helper.h>
  
  static int defx = 1024;
  static int defy = 768;
  
  module_param(defx, int, 0444);
  module_param(defy, int, 0444);
  MODULE_PARM_DESC(defx, "default x resolution");
  MODULE_PARM_DESC(defy, "default y resolution");
  
  /* ---------------------------------------------------------------------- */
  
  static const uint32_t bochs_formats[] = {
  	DRM_FORMAT_XRGB8888,
  	DRM_FORMAT_BGRX8888,
  };
  
  static void bochs_plane_update(struct bochs_device *bochs,
  			       struct drm_plane_state *state)
  {
  	struct drm_gem_vram_object *gbo;
  
  	if (!state->fb || !bochs->stride)
  		return;
  
  	gbo = drm_gem_vram_of_gem(state->fb->obj[0]);
  	bochs_hw_setbase(bochs,
  			 state->crtc_x,
  			 state->crtc_y,
  			 state->fb->pitches[0],
  			 state->fb->offsets[0] + gbo->bo.offset);
  	bochs_hw_setformat(bochs, state->fb->format);
  }
  
  static void bochs_pipe_enable(struct drm_simple_display_pipe *pipe,
  			      struct drm_crtc_state *crtc_state,
  			      struct drm_plane_state *plane_state)
  {
  	struct bochs_device *bochs = pipe->crtc.dev->dev_private;
  
  	bochs_hw_setmode(bochs, &crtc_state->mode);
  	bochs_plane_update(bochs, plane_state);
  }
  
  static void bochs_pipe_update(struct drm_simple_display_pipe *pipe,
  			      struct drm_plane_state *old_state)
  {
  	struct bochs_device *bochs = pipe->crtc.dev->dev_private;
  	struct drm_crtc *crtc = &pipe->crtc;
  
  	bochs_plane_update(bochs, pipe->plane.state);
  
  	if (crtc->state->event) {
  		spin_lock_irq(&crtc->dev->event_lock);
  		drm_crtc_send_vblank_event(crtc, crtc->state->event);
  		crtc->state->event = NULL;
  		spin_unlock_irq(&crtc->dev->event_lock);
  	}
  }
  
  static int bochs_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
  				 struct drm_plane_state *new_state)
  {
  	struct drm_gem_vram_object *gbo;
  
  	if (!new_state->fb)
  		return 0;
  	gbo = drm_gem_vram_of_gem(new_state->fb->obj[0]);
  	return drm_gem_vram_pin(gbo, DRM_GEM_VRAM_PL_FLAG_VRAM);
  }
  
  static void bochs_pipe_cleanup_fb(struct drm_simple_display_pipe *pipe,
  				  struct drm_plane_state *old_state)
  {
  	struct drm_gem_vram_object *gbo;
  
  	if (!old_state->fb)
  		return;
  	gbo = drm_gem_vram_of_gem(old_state->fb->obj[0]);
  	drm_gem_vram_unpin(gbo);
  }
  
  static const struct drm_simple_display_pipe_funcs bochs_pipe_funcs = {
  	.enable	    = bochs_pipe_enable,
  	.update	    = bochs_pipe_update,
  	.prepare_fb = bochs_pipe_prepare_fb,
  	.cleanup_fb = bochs_pipe_cleanup_fb,
  };
  
  static int bochs_connector_get_modes(struct drm_connector *connector)
  {
  	struct bochs_device *bochs =
  		container_of(connector, struct bochs_device, connector);
  	int count = 0;
  
  	if (bochs->edid)
  		count = drm_add_edid_modes(connector, bochs->edid);
  
  	if (!count) {
  		count = drm_add_modes_noedid(connector, 8192, 8192);
  		drm_set_preferred_mode(connector, defx, defy);
  	}
  	return count;
  }
  
  static enum drm_mode_status bochs_connector_mode_valid(struct drm_connector *connector,
  				      struct drm_display_mode *mode)
  {
  	struct bochs_device *bochs =
  		container_of(connector, struct bochs_device, connector);
  	unsigned long size = mode->hdisplay * mode->vdisplay * 4;
  
  	/*
  	 * Make sure we can fit two framebuffers into video memory.
  	 * This allows up to 1600x1200 with 16 MB (default size).
  	 * If you want more try this:
  	 *     'qemu -vga std -global VGA.vgamem_mb=32 $otherargs'
  	 */
  	if (size * 2 > bochs->fb_size)
  		return MODE_BAD;
  
  	return MODE_OK;
  }
  
  static const struct drm_connector_helper_funcs bochs_connector_connector_helper_funcs = {
  	.get_modes = bochs_connector_get_modes,
  	.mode_valid = bochs_connector_mode_valid,
  };
  
  static const struct drm_connector_funcs bochs_connector_connector_funcs = {
  	.dpms = drm_helper_connector_dpms,
  	.fill_modes = drm_helper_probe_single_connector_modes,
  	.destroy = drm_connector_cleanup,
  	.reset = drm_atomic_helper_connector_reset,
  	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
  	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
  };
  
  static void bochs_connector_init(struct drm_device *dev)
  {
  	struct bochs_device *bochs = dev->dev_private;
  	struct drm_connector *connector = &bochs->connector;
  
  	drm_connector_init(dev, connector, &bochs_connector_connector_funcs,
  			   DRM_MODE_CONNECTOR_VIRTUAL);
  	drm_connector_helper_add(connector,
  				 &bochs_connector_connector_helper_funcs);
  	drm_connector_register(connector);
  
  	bochs_hw_load_edid(bochs);
  	if (bochs->edid) {
  		DRM_INFO("Found EDID data blob.\n");
  		drm_connector_attach_edid_property(connector);
  		drm_connector_update_edid_property(connector, bochs->edid);
  	}
  }
  
  static struct drm_framebuffer *
  bochs_gem_fb_create(struct drm_device *dev, struct drm_file *file,
  		    const struct drm_mode_fb_cmd2 *mode_cmd)
  {
  	if (mode_cmd->pixel_format != DRM_FORMAT_XRGB8888 &&
  	    mode_cmd->pixel_format != DRM_FORMAT_BGRX8888)
  		return ERR_PTR(-EINVAL);
  
  	return drm_gem_fb_create(dev, file, mode_cmd);
  }
  
  const struct drm_mode_config_funcs bochs_mode_funcs = {
  	.fb_create = bochs_gem_fb_create,
  	.atomic_check = drm_atomic_helper_check,
  	.atomic_commit = drm_atomic_helper_commit,
  };
  
  int bochs_kms_init(struct bochs_device *bochs)
  {
  	drm_mode_config_init(bochs->dev);
  
  	bochs->dev->mode_config.max_width = 8192;
  	bochs->dev->mode_config.max_height = 8192;
  
  	bochs->dev->mode_config.fb_base = bochs->fb_base;
  	bochs->dev->mode_config.preferred_depth = 24;
  	bochs->dev->mode_config.prefer_shadow = 0;
  	bochs->dev->mode_config.prefer_shadow_fbdev = 1;
  	bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = true;
  
  	bochs->dev->mode_config.funcs = &bochs_mode_funcs;
  
  	bochs_connector_init(bochs->dev);
  	drm_simple_display_pipe_init(bochs->dev,
  				     &bochs->pipe,
  				     &bochs_pipe_funcs,
  				     bochs_formats,
  				     ARRAY_SIZE(bochs_formats),
  				     NULL,
  				     &bochs->connector);
  
  	drm_mode_config_reset(bochs->dev);
  
  	return 0;
  }
  
  void bochs_kms_fini(struct bochs_device *bochs)
  {
  	drm_atomic_helper_shutdown(bochs->dev);
  	drm_mode_config_cleanup(bochs->dev);
  }
  