text: /*
   * Copyright (C) 2016 Marek Vasut <marex@denx.de>
   *
   * This code is based on drivers/video/fbdev/mxsfb.c :
   * Copyright (C) 2010 Juergen Beisert, Pengutronix
   * Copyright (C) 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved.
   * Copyright (C) 2008 Embedded Alley Solutions, Inc All Rights Reserved.
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version 2
   * of the License, or (at your option) any later version.
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   */
  
  #include <linux/module.h>
  #include <linux/spinlock.h>
  #include <linux/clk.h>
  #include <linux/component.h>
  #include <linux/list.h>
  #include <linux/of_device.h>
  #include <linux/of_graph.h>
  #include <linux/of_reserved_mem.h>
  #include <linux/pm_runtime.h>
  #include <linux/reservation.h>
  
  #include <drm/drmP.h>
  #include <drm/drm_atomic.h>
  #include <drm/drm_atomic_helper.h>
  #include <drm/drm_crtc.h>
  #include <drm/drm_crtc_helper.h>
  #include <drm/drm_fb_helper.h>
  #include <drm/drm_fb_cma_helper.h>
  #include <drm/drm_gem_cma_helper.h>
  #include <drm/drm_of.h>
  #include <drm/drm_panel.h>
  #include <drm/drm_simple_kms_helper.h>
  
  #include "mxsfb_drv.h"
  #include "mxsfb_regs.h"
  
  enum mxsfb_devtype {
  	MXSFB_V3,
  	MXSFB_V4,
  };
  
  static const struct mxsfb_devdata mxsfb_devdata[] = {
  	[MXSFB_V3] = {
  		.transfer_count	= LCDC_V3_TRANSFER_COUNT,
  		.cur_buf	= LCDC_V3_CUR_BUF,
  		.next_buf	= LCDC_V3_NEXT_BUF,
  		.debug0		= LCDC_V3_DEBUG0,
  		.hs_wdth_mask	= 0xff,
  		.hs_wdth_shift	= 24,
  		.ipversion	= 3,
  	},
  	[MXSFB_V4] = {
  		.transfer_count	= LCDC_V4_TRANSFER_COUNT,
  		.cur_buf	= LCDC_V4_CUR_BUF,
  		.next_buf	= LCDC_V4_NEXT_BUF,
  		.debug0		= LCDC_V4_DEBUG0,
  		.hs_wdth_mask	= 0x3fff,
  		.hs_wdth_shift	= 18,
  		.ipversion	= 4,
  	},
  };
  
  static const uint32_t mxsfb_formats[] = {
  	DRM_FORMAT_XRGB8888,
  	DRM_FORMAT_RGB565
  };
  
  static struct mxsfb_drm_private *
  drm_pipe_to_mxsfb_drm_private(struct drm_simple_display_pipe *pipe)
  {
  	return container_of(pipe, struct mxsfb_drm_private, pipe);
  }
  
  void mxsfb_enable_axi_clk(struct mxsfb_drm_private *mxsfb)
  {
  	if (mxsfb->clk_axi)
  		clk_prepare_enable(mxsfb->clk_axi);
  }
  
  void mxsfb_disable_axi_clk(struct mxsfb_drm_private *mxsfb)
  {
  	if (mxsfb->clk_axi)
  		clk_disable_unprepare(mxsfb->clk_axi);
  }
  
  static const struct drm_mode_config_funcs mxsfb_mode_config_funcs = {
  	.fb_create		= drm_fb_cma_create,
  	.atomic_check		= drm_atomic_helper_check,
  	.atomic_commit		= drm_atomic_helper_commit,
  };
  
  static void mxsfb_pipe_enable(struct drm_simple_display_pipe *pipe,
  			      struct drm_crtc_state *crtc_state)
  {
  	struct mxsfb_drm_private *mxsfb = drm_pipe_to_mxsfb_drm_private(pipe);
  
  	drm_panel_prepare(mxsfb->panel);
  	mxsfb_crtc_enable(mxsfb);
  	drm_panel_enable(mxsfb->panel);
  }
  
  static void mxsfb_pipe_disable(struct drm_simple_display_pipe *pipe)
  {
  	struct mxsfb_drm_private *mxsfb = drm_pipe_to_mxsfb_drm_private(pipe);
  
  	drm_panel_disable(mxsfb->panel);
  	mxsfb_crtc_disable(mxsfb);
  	drm_panel_unprepare(mxsfb->panel);
  }
  
  static void mxsfb_pipe_update(struct drm_simple_display_pipe *pipe,
  			      struct drm_plane_state *plane_state)
  {
  	struct mxsfb_drm_private *mxsfb = drm_pipe_to_mxsfb_drm_private(pipe);
  
  	mxsfb_plane_atomic_update(mxsfb, plane_state);
  }
  
  static int mxsfb_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
  				 struct drm_plane_state *plane_state)
  {
  	return drm_fb_cma_prepare_fb(&pipe->plane, plane_state);
  }
  
  static struct drm_simple_display_pipe_funcs mxsfb_funcs = {
  	.enable		= mxsfb_pipe_enable,
  	.disable	= mxsfb_pipe_disable,
  	.update		= mxsfb_pipe_update,
  	.prepare_fb	= mxsfb_pipe_prepare_fb,
  };
  
  static int mxsfb_load(struct drm_device *drm, unsigned long flags)
  {
  	struct platform_device *pdev = to_platform_device(drm->dev);
  	struct mxsfb_drm_private *mxsfb;
  	struct resource *res;
  	int ret;
  
  	mxsfb = devm_kzalloc(&pdev->dev, sizeof(*mxsfb), GFP_KERNEL);
  	if (!mxsfb)
  		return -ENOMEM;
  
  	drm->dev_private = mxsfb;
  	mxsfb->devdata = &mxsfb_devdata[pdev->id_entry->driver_data];
  
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	mxsfb->base = devm_ioremap_resource(drm->dev, res);
  	if (IS_ERR(mxsfb->base))
  		return PTR_ERR(mxsfb->base);
  
  	mxsfb->clk = devm_clk_get(drm->dev, NULL);
  	if (IS_ERR(mxsfb->clk))
  		return PTR_ERR(mxsfb->clk);
  
  	mxsfb->clk_axi = devm_clk_get(drm->dev, "axi");
  	if (IS_ERR(mxsfb->clk_axi))
  		mxsfb->clk_axi = NULL;
  
  	mxsfb->clk_disp_axi = devm_clk_get(drm->dev, "disp_axi");
  	if (IS_ERR(mxsfb->clk_disp_axi))
  		mxsfb->clk_disp_axi = NULL;
  
  	ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
  	if (ret)
  		return ret;
  
  	pm_runtime_enable(drm->dev);
  
  	ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
  	if (ret < 0) {
  		dev_err(drm->dev, "Failed to initialise vblank\n");
  		goto err_vblank;
  	}
  
  	/* Modeset init */
  	drm_mode_config_init(drm);
  
  	ret = mxsfb_create_output(drm);
  	if (ret < 0) {
  		dev_err(drm->dev, "Failed to create outputs\n");
  		goto err_vblank;
  	}
  
  	ret = drm_simple_display_pipe_init(drm, &mxsfb->pipe, &mxsfb_funcs,
  			mxsfb_formats, ARRAY_SIZE(mxsfb_formats),
  			&mxsfb->connector);
  	if (ret < 0) {
  		dev_err(drm->dev, "Cannot setup simple display pipe\n");
  		goto err_vblank;
  	}
  
  	ret = drm_panel_attach(mxsfb->panel, &mxsfb->connector);
  	if (ret) {
  		dev_err(drm->dev, "Cannot connect panel\n");
  		goto err_vblank;
  	}
  
  	drm->mode_config.min_width	= MXSFB_MIN_XRES;
  	drm->mode_config.min_height	= MXSFB_MIN_YRES;
  	drm->mode_config.max_width	= MXSFB_MAX_XRES;
  	drm->mode_config.max_height	= MXSFB_MAX_YRES;
  	drm->mode_config.funcs		= &mxsfb_mode_config_funcs;
  
  	drm_mode_config_reset(drm);
  
  	pm_runtime_get_sync(drm->dev);
  	ret = drm_irq_install(drm, platform_get_irq(pdev, 0));
  	pm_runtime_put_sync(drm->dev);
  
  	if (ret < 0) {
  		dev_err(drm->dev, "Failed to install IRQ handler\n");
  		goto err_irq;
  	}
  
  	drm_kms_helper_poll_init(drm);
  
  	mxsfb->fbdev = drm_fbdev_cma_init(drm, 32,
  					  drm->mode_config.num_connector);
  	if (IS_ERR(mxsfb->fbdev)) {
  		ret = PTR_ERR(mxsfb->fbdev);
  		mxsfb->fbdev = NULL;
  		dev_err(drm->dev, "Failed to init FB CMA area\n");
  		goto err_cma;
  	}
  
  	platform_set_drvdata(pdev, drm);
  
  	drm_helper_hpd_irq_event(drm);
  
  	return 0;
  
  err_cma:
  	drm_irq_uninstall(drm);
  err_irq:
  	drm_panel_detach(mxsfb->panel);
  err_vblank:
  	pm_runtime_disable(drm->dev);
  
  	return ret;
  }
  
  static void mxsfb_unload(struct drm_device *drm)
  {
  	struct mxsfb_drm_private *mxsfb = drm->dev_private;
  
  	if (mxsfb->fbdev)
  		drm_fbdev_cma_fini(mxsfb->fbdev);
  
  	drm_kms_helper_poll_fini(drm);
  	drm_mode_config_cleanup(drm);
  	drm_vblank_cleanup(drm);
  
  	pm_runtime_get_sync(drm->dev);
  	drm_irq_uninstall(drm);
  	pm_runtime_put_sync(drm->dev);
  
  	drm->dev_private = NULL;
  
  	pm_runtime_disable(drm->dev);
  }
  
  static void mxsfb_lastclose(struct drm_device *drm)
  {
  	struct mxsfb_drm_private *mxsfb = drm->dev_private;
  
  	drm_fbdev_cma_restore_mode(mxsfb->fbdev);
  }
  
  static int mxsfb_enable_vblank(struct drm_device *drm, unsigned int crtc)
  {
  	struct mxsfb_drm_private *mxsfb = drm->dev_private;
  
  	/* Clear and enable VBLANK IRQ */
  	mxsfb_enable_axi_clk(mxsfb);
  	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
  	writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_SET);
  	mxsfb_disable_axi_clk(mxsfb);
  
  	return 0;
  }
  
  static void mxsfb_disable_vblank(struct drm_device *drm, unsigned int crtc)
  {
  	struct mxsfb_drm_private *mxsfb = drm->dev_private;
  
  	/* Disable and clear VBLANK IRQ */
  	mxsfb_enable_axi_clk(mxsfb);
  	writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_CLR);
  	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
  	mxsfb_disable_axi_clk(mxsfb);
  }
  
  static void mxsfb_irq_preinstall(struct drm_device *drm)
  {
  	mxsfb_disable_vblank(drm, 0);
  }
  
  static irqreturn_t mxsfb_irq_handler(int irq, void *data)
  {
  	struct drm_device *drm = data;
  	struct mxsfb_drm_private *mxsfb = drm->dev_private;
  	u32 reg;
  
  	mxsfb_enable_axi_clk(mxsfb);
  
  	reg = readl(mxsfb->base + LCDC_CTRL1);
  
  	if (reg & CTRL1_CUR_FRAME_DONE_IRQ)
  		drm_crtc_handle_vblank(&mxsfb->pipe.crtc);
  
  	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
  
  	mxsfb_disable_axi_clk(mxsfb);
  
  	return IRQ_HANDLED;
  }
  
  DEFINE_DRM_GEM_CMA_FOPS(fops);
  
  static struct drm_driver mxsfb_driver = {
  	.driver_features	= DRIVER_GEM | DRIVER_MODESET |
  				  DRIVER_PRIME | DRIVER_ATOMIC |
  				  DRIVER_HAVE_IRQ,
  	.lastclose		= mxsfb_lastclose,
  	.irq_handler		= mxsfb_irq_handler,
  	.irq_preinstall		= mxsfb_irq_preinstall,
  	.irq_uninstall		= mxsfb_irq_preinstall,
  	.enable_vblank		= mxsfb_enable_vblank,
  	.disable_vblank		= mxsfb_disable_vblank,
  	.gem_free_object	= drm_gem_cma_free_object,
  	.gem_vm_ops		= &drm_gem_cma_vm_ops,
  	.dumb_create		= drm_gem_cma_dumb_create,
  	.dumb_map_offset	= drm_gem_cma_dumb_map_offset,
  	.dumb_destroy		= drm_gem_dumb_destroy,
  	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd,
  	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle,
  	.gem_prime_export	= drm_gem_prime_export,
  	.gem_prime_import	= drm_gem_prime_import,
  	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
  	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
  	.gem_prime_vmap		= drm_gem_cma_prime_vmap,
  	.gem_prime_vunmap	= drm_gem_cma_prime_vunmap,
  	.gem_prime_mmap		= drm_gem_cma_prime_mmap,
  	.fops	= &fops,
  	.name	= "mxsfb-drm",
  	.desc	= "MXSFB Controller DRM",
  	.date	= "20160824",
  	.major	= 1,
  	.minor	= 0,
  };
  
  static const struct platform_device_id mxsfb_devtype[] = {
  	{ .name = "imx23-fb", .driver_data = MXSFB_V3, },
  	{ .name = "imx28-fb", .driver_data = MXSFB_V4, },
  	{ .name = "imx6sx-fb", .driver_data = MXSFB_V4, },
  	{ /* sentinel */ }
  };
  MODULE_DEVICE_TABLE(platform, mxsfb_devtype);
  
  static const struct of_device_id mxsfb_dt_ids[] = {
  	{ .compatible = "fsl,imx23-lcdif", .data = &mxsfb_devtype[0], },
  	{ .compatible = "fsl,imx28-lcdif", .data = &mxsfb_devtype[1], },
  	{ .compatible = "fsl,imx6sx-lcdif", .data = &mxsfb_devtype[2], },
  	{ /* sentinel */ }
  };
  MODULE_DEVICE_TABLE(of, mxsfb_dt_ids);
  
  static int mxsfb_probe(struct platform_device *pdev)
  {
  	struct drm_device *drm;
  	const struct of_device_id *of_id =
  			of_match_device(mxsfb_dt_ids, &pdev->dev);
  	int ret;
  
  	if (!pdev->dev.of_node)
  		return -ENODEV;
  
  	if (of_id)
  		pdev->id_entry = of_id->data;
  
  	drm = drm_dev_alloc(&mxsfb_driver, &pdev->dev);
  	if (IS_ERR(drm))
  		return PTR_ERR(drm);
  
  	ret = mxsfb_load(drm, 0);
  	if (ret)
  		goto err_free;
  
  	ret = drm_dev_register(drm, 0);
  	if (ret)
  		goto err_unload;
  
  	return 0;
  
  err_unload:
  	mxsfb_unload(drm);
  err_free:
  	drm_dev_unref(drm);
  
  	return ret;
  }
  
  static int mxsfb_remove(struct platform_device *pdev)
  {
  	struct drm_device *drm = platform_get_drvdata(pdev);
  
  	drm_dev_unregister(drm);
  	mxsfb_unload(drm);
  	drm_dev_unref(drm);
  
  	return 0;
  }
  
  static struct platform_driver mxsfb_platform_driver = {
  	.probe		= mxsfb_probe,
  	.remove		= mxsfb_remove,
  	.id_table	= mxsfb_devtype,
  	.driver	= {
  		.name		= "mxsfb",
  		.of_match_table	= mxsfb_dt_ids,
  	},
  };
  
  module_platform_driver(mxsfb_platform_driver);
  
  MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
  MODULE_DESCRIPTION("Freescale MXS DRM/KMS driver");
  MODULE_LICENSE("GPL");
  