Re: [RFC v2 7/8] drm/mediatek: Add DRM-based framebuffer device

Hi Ulrich,

On Mon, 2017-10-16 at 17:31 +0200, Ulrich Hecht wrote:

Add fbdev support to the Mediatek DRM driver.

Signed-off-by: CK Hu ck.hu@mediatek.com Signed-off-by: YT Shen yt.shen@mediatek.com Signed-off-by: Philipp Zabel p.zabel@pengutronix.de Signed-off-by: Daniel Kurtz djkurtz@chromium.org [uli: Forward-ported from chromeos-3.18 vendor kernel.] Signed-off-by: Ulrich Hecht ulrich.hecht+renesas@gmail.com

---

drivers/gpu/drm/mediatek/Makefile | 2 + drivers/gpu/drm/mediatek/mtk_drm_drv.c | 8 ++ drivers/gpu/drm/mediatek/mtk_drm_drv.h | 4 +- drivers/gpu/drm/mediatek/mtk_drm_fb.c | 13 +++ drivers/gpu/drm/mediatek/mtk_drm_fb.h | 3 + drivers/gpu/drm/mediatek/mtk_drm_fbdev.c | 181 +++++++++++++++++++++++++++++++ drivers/gpu/drm/mediatek/mtk_drm_fbdev.h | 32 ++++++ 7 files changed, 242 insertions(+), 1 deletion(-) create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_fbdev.c create mode 100644 drivers/gpu/drm/mediatek/mtk_drm_fbdev.h

diff --git a/drivers/gpu/drm/mediatek/Makefile b/drivers/gpu/drm/mediatek/Makefile index e37b55a..8306fb5 100644 --- a/drivers/gpu/drm/mediatek/Makefile +++ b/drivers/gpu/drm/mediatek/Makefile @@ -12,6 +12,8 @@ mediatek-drm-y := mtk_disp_color.o \ mtk_mipi_tx.o \ mtk_dpi.o

+mediatek-drm-$(CONFIG_DRM_FBDEV_EMULATION) += mtk_drm_fbdev.o

obj-$(CONFIG_DRM_MEDIATEK) += mediatek-drm.o

mediatek-drm-hdmi-objs := mtk_cec.o \ diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c index ce99921..636b8db 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c @@ -30,6 +30,7 @@ #include "mtk_drm_ddp_comp.h" #include "mtk_drm_drv.h" #include "mtk_drm_fb.h" +#include "mtk_drm_fbdev.h" #include "mtk_drm_gem.h"

#define DRIVER_NAME "mediatek" @@ -257,8 +258,14 @@ static int mtk_drm_kms_init(struct drm_device *drm) drm_kms_helper_poll_init(drm); drm_mode_config_reset(drm);

• ret = mtk_fbdev_init(drm);
• if (ret)

• goto err_kms_helper_poll_fini;
  

• return 0;

+err_kms_helper_poll_fini:

• drm_kms_helper_poll_fini(drm);

err_component_unbind: component_unbind_all(drm->dev, drm); err_config_cleanup: @@ -269,6 +276,7 @@ static int mtk_drm_kms_init(struct drm_device *drm)

static void mtk_drm_kms_deinit(struct drm_device *drm) {

• mtk_fbdev_fini(drm); drm_kms_helper_poll_fini(drm);

  component_unbind_all(drm->dev, drm);

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.h b/drivers/gpu/drm/mediatek/mtk_drm_drv.h index c3378c4..4edc002 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.h +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.h @@ -14,6 +14,7 @@ #ifndef MTK_DRM_DRV_H #define MTK_DRM_DRV_H

+#include <drm/drm_fb_helper.h> #include <linux/io.h> #include "mtk_drm_ddp_comp.h"

@@ -24,7 +25,6 @@ struct device; struct device_node; struct drm_crtc; struct drm_device; -struct drm_fb_helper; struct drm_property; struct regmap;

@@ -56,6 +56,8 @@ struct mtk_drm_private { } commit;

struct drm_atomic_state *suspend_state;

• struct drm_fb_helper fb_helper;
• struct drm_gem_object *fbdev_bo;

};

extern struct platform_driver mtk_ddp_driver; diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fb.c b/drivers/gpu/drm/mediatek/mtk_drm_fb.c index 0d8d506..ac8561d 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_fb.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_fb.c @@ -96,6 +96,19 @@ static struct mtk_drm_fb *mtk_drm_framebuffer_init(struct drm_device *dev, return mtk_fb; }

+struct drm_framebuffer *mtk_drm_framebuffer_create(struct drm_device *dev,

• const struct drm_mode_fb_cmd2 *mode,
  

• struct drm_gem_object *obj)
  

+{

• struct mtk_drm_fb *mtk_fb;
• mtk_fb = mtk_drm_framebuffer_init(dev, mode, obj);
• if (IS_ERR(mtk_fb))

• return ERR_CAST(mtk_fb);
  

• return &mtk_fb->base;

+}

/*

• Wait for any exclusive fence in fb's gem object's reservation object.

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fb.h b/drivers/gpu/drm/mediatek/mtk_drm_fb.h index 9b2ae34..9ee1ac2 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_fb.h +++ b/drivers/gpu/drm/mediatek/mtk_drm_fb.h @@ -19,5 +19,8 @@ int mtk_fb_wait(struct drm_framebuffer *fb); struct drm_framebuffer *mtk_drm_mode_fb_create(struct drm_device *dev, struct drm_file *file, const struct drm_mode_fb_cmd2 *cmd); +struct drm_framebuffer *mtk_drm_framebuffer_create(struct drm_device *dev,

• const struct drm_mode_fb_cmd2 *mode,
  

• struct drm_gem_object *obj);
  
  

#endif /* MTK_DRM_FB_H */ diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fbdev.c b/drivers/gpu/drm/mediatek/mtk_drm_fbdev.c new file mode 100644 index 0000000..9193647 --- /dev/null +++ b/drivers/gpu/drm/mediatek/mtk_drm_fbdev.c @@ -0,0 +1,181 @@ +/*

• • Copyright (c) 2016 MediaTek Inc.
• • This program is free software; you can redistribute it and/or modify
• • it under the terms of the GNU General Public License version 2 as
• • published by the Free Software Foundation.
• • 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 <drm/drmP.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_fb_helper.h> +#include <drm/drm_gem.h>

+#include "mtk_drm_drv.h" +#include "mtk_drm_fb.h"

This should

#include "mtk_drm_fbdev.h"

as well, to avoid warnings (see below) and make sure the header declarations match the implementation.

+#include "mtk_drm_gem.h"

+#define to_drm_private(x) \

• container_of(x, struct mtk_drm_private, fb_helper)
  

+#if 1

This superfluous "#if 1" should be removed ...

+static int mtk_drm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma) +{

• struct drm_fb_helper *helper = info->par;
• struct mtk_drm_private *private = helper->dev->dev_private;
• return mtk_drm_gem_mmap_buf(private->fbdev_bo, vma);

+} +#endif

... together with this "#endif".

+static struct fb_ops mtk_fbdev_ops = {

• .owner = THIS_MODULE,
• .fb_fillrect = drm_fb_helper_cfb_fillrect,
• .fb_copyarea = drm_fb_helper_cfb_copyarea,
• .fb_imageblit = drm_fb_helper_cfb_imageblit,
• .fb_check_var = drm_fb_helper_check_var,
• .fb_set_par = drm_fb_helper_set_par,
• .fb_blank = drm_fb_helper_blank,
• .fb_pan_display = drm_fb_helper_pan_display,
• .fb_setcmap = drm_fb_helper_setcmap,
• .fb_mmap = mtk_drm_fbdev_mmap,

+};

+static int mtk_fbdev_probe(struct drm_fb_helper *helper,

• 	   struct drm_fb_helper_surface_size *sizes)
  

+{

• struct drm_device *dev = helper->dev;
• struct mtk_drm_private *private = helper->dev->dev_private;
• struct drm_mode_fb_cmd2 mode = { 0 };
• struct mtk_drm_gem_obj *mtk_gem;
• struct fb_info *info;
• struct drm_framebuffer *fb;
• unsigned int bytes_per_pixel;
• unsigned long offset;
• size_t size;
• int err;
• bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
• mode.width = sizes->surface_width;
• mode.height = sizes->surface_height;
• mode.pitches[0] = sizes->surface_width * bytes_per_pixel;
• mode.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,

• 				      sizes->surface_depth);
  

• size = mode.pitches[0] * mode.height;
• mtk_gem = mtk_drm_gem_create(dev, size, true);
• if (IS_ERR(mtk_gem))

• return PTR_ERR(mtk_gem);
  

• private->fbdev_bo = &mtk_gem->base;
• info = drm_fb_helper_alloc_fbi(helper);
• if (IS_ERR(info)) {

• err = PTR_ERR(info);
  

• dev_err(dev->dev, "failed to allocate framebuffer info, %d\n",
  

• 	err);
  

• goto err_gem_free_object;
  

• }
• fb = mtk_drm_framebuffer_create(dev, &mode, private->fbdev_bo);
• if (IS_ERR(fb)) {

• err = PTR_ERR(fb);
  

• dev_err(dev->dev, "failed to allocate DRM framebuffer, %d\n",
  

• 	err);
  

• goto err_release_fbi;
  

• }
• helper->fb = fb;
• info->par = helper;
• info->flags = FBINFO_FLAG_DEFAULT;
• info->fbops = &mtk_fbdev_ops;
• drm_fb_helper_fill_fix(info, fb->pitches[0], fb->format->depth);
• drm_fb_helper_fill_var(info, helper, sizes->fb_width, sizes->fb_height);
• offset = info->var.xoffset * bytes_per_pixel;
• offset += info->var.yoffset * fb->pitches[0];
• dev->mode_config.fb_base = 0;
• info->screen_base = mtk_gem->kvaddr + offset;

To store non-__iomem pointers, there is info->screen_buffer instead of info->screen_base, see commit 17a7b0b4d974 ("fb.h: Provide alternate screen_base pointer").

• info->screen_size = size;
• info->fix.smem_len = size;
• DRM_DEBUG_KMS("FB [%ux%u]-%u offset=%lu size=%zd\n",

•       fb->width, fb->height, fb->format->depth, offset, size);
  

• info->skip_vt_switch = true;
• return 0;

+err_release_fbi: +err_gem_free_object:

• mtk_drm_gem_free_object(&mtk_gem->base);
• return err;

+}

+static const struct drm_fb_helper_funcs mtk_drm_fb_helper_funcs = {

• .fb_probe = mtk_fbdev_probe,

+};

+int mtk_fbdev_init(struct drm_device *dev)

drivers/gpu/drm/mediatek/mtk_drm_fbdev.c:128:5: warning: symbol 'mtk_fbdev_init' was not declared. Should it be static?

+{

• struct mtk_drm_private *priv = dev->dev_private;
• struct drm_fb_helper *helper = &priv->fb_helper;
• int ret;
• if (!dev->mode_config.num_crtc || !dev->mode_config.num_connector)

• return -EINVAL;
  

• drm_fb_helper_prepare(dev, helper, &mtk_drm_fb_helper_funcs);
• ret = drm_fb_helper_init(dev, helper,

• 		 dev->mode_config.num_connector);
  

• if (ret) {

• dev_err(dev->dev, "failed to initialize DRM FB helper, %d\n",
  

• 	ret);
  

• goto fini;
  

• }
• ret = drm_fb_helper_single_add_all_connectors(helper);
• if (ret) {

• dev_err(dev->dev, "failed to add connectors, %d\n", ret);
  

• goto fini;
  

• }
• ret = drm_fb_helper_initial_config(helper, 32);
• if (ret) {

• dev_err(dev->dev, "failed to set initial configuration, %d\n",
  

• 	ret);
  

• goto fini;
  

• }
• return 0;

+fini:

• drm_fb_helper_fini(helper);
• return ret;

+}

+void mtk_fbdev_fini(struct drm_device *dev)

drivers/gpu/drm/mediatek/mtk_drm_fbdev.c:168:6: warning: symbol 'mtk_fbdev_fini' was not declared. Should it be static?

+{

• struct mtk_drm_private *priv = dev->dev_private;
• struct drm_fb_helper *helper = &priv->fb_helper;
• drm_fb_helper_unregister_fbi(helper);
• if (helper->fb) {

• drm_framebuffer_unregister_private(helper->fb);
  

• drm_framebuffer_remove(helper->fb);
  

• }
• drm_fb_helper_fini(helper);

+} diff --git a/drivers/gpu/drm/mediatek/mtk_drm_fbdev.h b/drivers/gpu/drm/mediatek/mtk_drm_fbdev.h new file mode 100644 index 0000000..f3e0949 --- /dev/null +++ b/drivers/gpu/drm/mediatek/mtk_drm_fbdev.h @@ -0,0 +1,32 @@ +/*

• • Copyright (c) 2016 MediaTek Inc.
• • This program is free software; you can redistribute it and/or modify
• • it under the terms of the GNU General Public License version 2 as
• • published by the Free Software Foundation.
• • 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.
• */

+#ifndef MTK_DRM_FBDEV_H +#define MTK_DRM_FBDEV_H

+#ifdef CONFIG_DRM_FBDEV_EMULATION +int mtk_fbdev_init(struct drm_device *dev); +void mtk_fbdev_fini(struct drm_device *dev); +#else +int mtk_fbdev_init(struct drm_device *dev)

[...]

+void mtk_fbdev_fini(struct drm_device *dev)

These two should be static inline:

drivers/gpu/drm/mediatek/mtk_drm_fbdev.h:21:5: warning: symbol 'mtk_fbdev_init' was not declared. Should it be static? drivers/gpu/drm/mediatek/mtk_drm_fbdev.h:26:6: warning: symbol 'mtk_fbdev_fini' was not declared. Should it be static?

regards Philipp