Re: [PATCH v3 01/11] drm/mediatek: Add interface to allocate MediaTek GEM buffer.

[Jason-JH Lin (林睿祥)]

Hi CK,

Thanks for the reviews.

On Mon, 2023-12-25 at 09:05 +0000, CK Hu (胡俊光) wrote:
> Hi, Jason:
> 
> 
> On Sun, 2023-12-24 at 02:29 +0800, Jason-JH.Lin wrote:
> > From: CK Hu <ck.hu@xxxxxxxxxxxx>
> > 
> > Add an interface to allocate MediaTek GEM buffers, allow the IOCTLs
> > to be used by render nodes.
> > This patch also sets the RENDER driver feature.
> > 
> > Signed-off-by: CK Hu <ck.hu@xxxxxxxxxxxx>
> > Signed-off-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx>
> > Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
> > Signed-off-by: Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>
> > Reviewed-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>
> > Reviewed-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx>
> > Tested-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>
> > Tested-by: Pi-Hsun Shih <pihsun@xxxxxxxxxxxx>
> > ---
> >  drivers/gpu/drm/mediatek/mtk_drm_drv.c | 13 ++++++
> >  drivers/gpu/drm/mediatek/mtk_drm_gem.c | 39 +++++++++++++++++
> >  drivers/gpu/drm/mediatek/mtk_drm_gem.h | 12 ++++++
> >  include/uapi/drm/mediatek_drm.h        | 58
> > ++++++++++++++++++++++++++
> >  4 files changed, 122 insertions(+)
> >  create mode 100644 include/uapi/drm/mediatek_drm.h
> > 
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> > b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> > index 2b0c35cacbc6..5d2a39e491aa 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> > @@ -24,6 +24,7 @@
> >  #include <drm/drm_of.h>
> >  #include <drm/drm_probe_helper.h>
> >  #include <drm/drm_vblank.h>
> > +#include <drm/mediatek_drm.h>
> >  
> >  #include "mtk_drm_crtc.h"
> >  #include "mtk_drm_ddp_comp.h"
> > @@ -569,6 +570,14 @@ static void mtk_drm_kms_deinit(struct
> > drm_device
> > *drm)
> >  	component_unbind_all(drm->dev, drm);
> >  }
> >  
> > +static const struct drm_ioctl_desc mtk_ioctls[] = {
> > +	DRM_IOCTL_DEF_DRV(MTK_GEM_CREATE, mtk_gem_create_ioctl,
> > +			  DRM_UNLOCKED | DRM_AUTH | DRM_RENDER_ALLOW),
> > +	DRM_IOCTL_DEF_DRV(MTK_GEM_MAP_OFFSET,
> > +			  mtk_gem_map_offset_ioctl,
> > +			  DRM_UNLOCKED | DRM_AUTH | DRM_RENDER_ALLOW),
> 
> For secure buffer, we don't need map offset function. If you really
> need this function, separate this to another patch and describe why
> need this.
> 
> Regards,
> CK

OK, I'll remove this function.

Regards
Jason-JH.Lin
> 
> > +};
> > +
> >  DEFINE_DRM_GEM_FOPS(mtk_drm_fops);
> >  
> >  /*
> > @@ -590,6 +599,10 @@ static const struct drm_driver mtk_drm_driver
> > =
> > {
> >  
> >  	.gem_prime_import = mtk_drm_gem_prime_import,
> >  	.gem_prime_import_sg_table = mtk_gem_prime_import_sg_table,
> > +
> > +	.ioctls = mtk_ioctls,
> > +	.num_ioctls = ARRAY_SIZE(mtk_ioctls),
> > +
> >  	.fops = &mtk_drm_fops,
> >  
> >  	.name = DRIVER_NAME,
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> > b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> > index 4f2e3feabc0f..30e347adcbe9 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
> > @@ -4,6 +4,7 @@
> >   */
> >  
> >  #include <linux/dma-buf.h>
> > +#include <drm/mediatek_drm.h>
> >  
> >  #include <drm/drm.h>
> >  #include <drm/drm_device.h>
> > @@ -283,3 +284,41 @@ void mtk_drm_gem_prime_vunmap(struct
> > drm_gem_object *obj,
> >  	mtk_gem->kvaddr = NULL;
> >  	kfree(mtk_gem->pages);
> >  }
> > +
> > +int mtk_gem_map_offset_ioctl(struct drm_device *drm, void *data,
> > +			     struct drm_file *file_priv)
> > +{
> > +	struct drm_mtk_gem_map_off *args = data;
> > +
> > +	return drm_gem_dumb_map_offset(file_priv, drm, args->handle,
> > +				       &args->offset);
> > +}
> > +
> > +int mtk_gem_create_ioctl(struct drm_device *dev, void *data,
> > +			 struct drm_file *file_priv)
> > +{
> > +	struct mtk_drm_gem_obj *mtk_gem;
> > +	struct drm_mtk_gem_create *args = data;
> > +	int ret;
> > +
> > +	mtk_gem = mtk_drm_gem_create(dev, args->size, false);
> > +	if (IS_ERR(mtk_gem))
> > +		return PTR_ERR(mtk_gem);
> > +
> > +	/*
> > +	 * allocate a id of idr table where the obj is registered
> > +	 * and handle has the id what user can see.
> > +	 */
> > +	ret = drm_gem_handle_create(file_priv, &mtk_gem->base, &args-
> > > handle);
> > 
> > +	if (ret)
> > +		goto err_handle_create;
> > +
> > +	/* drop reference from allocate - handle holds it now. */
> > +	drm_gem_object_put(&mtk_gem->base);
> > +
> > +	return 0;
> > +
> > +err_handle_create:
> > +	mtk_drm_gem_free_object(&mtk_gem->base);
> > +	return ret;
> > +}
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.h
> > b/drivers/gpu/drm/mediatek/mtk_drm_gem.h
> > index 78f23b07a02e..90f3d2916ec5 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.h
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.h
> > @@ -46,4 +46,16 @@ int mtk_drm_gem_prime_vmap(struct drm_gem_object
> > *obj, struct iosys_map *map);
> >  void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj,
> >  			      struct iosys_map *map);
> >  
> > +/*
> > + * request gem object creation and buffer allocation as the size
> > + * that it is calculated with framebuffer information such as
> > width,
> > + * height and bpp.
> > + */
> > +int mtk_gem_create_ioctl(struct drm_device *dev, void *data,
> > +			 struct drm_file *file_priv);
> > +
> > +/* get buffer offset to map to user space. */
> > +int mtk_gem_map_offset_ioctl(struct drm_device *dev, void *data,
> > +			     struct drm_file *file_priv);
> > +
> >  #endif
> > diff --git a/include/uapi/drm/mediatek_drm.h
> > b/include/uapi/drm/mediatek_drm.h
> > new file mode 100644
> > index 000000000000..f4d47577c94e
> > --- /dev/null
> > +++ b/include/uapi/drm/mediatek_drm.h
> > @@ -0,0 +1,58 @@
> > +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
> > +/*
> > + * Copyright (c) 2015 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 _UAPI_MEDIATEK_DRM_H
> > +#define _UAPI_MEDIATEK_DRM_H
> > +
> > +#include <drm/drm.h>
> > +
> > +/**
> > + * struct drm_mtk_gem_create - User-desired buffer creation
> > information structure.
> > + *
> > + * @size: user-desired memory allocation size.
> > + *	- this size value would be page-aligned internally.
> > + * @flags: user request for setting memory type or cache
> > attributes.
> > + * @handle: returned a handle to created gem object.
> > + *	- this handle will be set by gem module of kernel side.
> > + */
> > +struct drm_mtk_gem_create {
> > +	uint64_t size;
> > +	uint32_t flags;
> > +	uint32_t handle;
> > +};
> > +
> > +/**
> > + * struct drm_mtk_gem_map_off - A structure for getting buffer
> > offset.
> > + *
> > + * @handle: a pointer to gem object created.
> > + * @pad: just padding to be 64-bit aligned.
> > + * @offset: relatived offset value of the memory region allocated.
> > + *     - this value should be set by user.
> > + */
> > +struct drm_mtk_gem_map_off {
> > +	uint32_t handle;
> > +	uint32_t pad;
> > +	uint64_t offset;
> > +};
> > +
> > +#define DRM_MTK_GEM_CREATE		0x00
> > +#define DRM_MTK_GEM_MAP_OFFSET		0x01
> > +
> > +#define DRM_IOCTL_MTK_GEM_CREATE	DRM_IOWR(DRM_COMMAND_BASE + \
> > +		DRM_MTK_GEM_CREATE, struct drm_mtk_gem_create)
> > +
> > +#define DRM_IOCTL_MTK_GEM_MAP_OFFSET	DRM_IOWR(DRM_COMMAND_BA
> > SE + \
> > +		DRM_MTK_GEM_MAP_OFFSET, struct drm_mtk_gem_map_off)
> > +
> > +#endif /* _UAPI_MEDIATEK_DRM_H */