Commit 38b2d9d3 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/format-helper: Cache buffers with struct drm_format_conv_state 



Hold temporary memory for format conversion in an instance of struct
drm_format_conv_state. Update internal helpers of DRM's format-conversion
code accordingly. Drivers will later be able to maintain this cache by
themselves.

Besides caching, struct drm_format_conv_state will be useful to hold
additional information for format conversion, such as palette data or
foreground/background colors. This will enable conversion from indexed
color formats to component-based formats.

v5:
	* improve documentation (Javier, Noralf)
v3:
	* rename struct drm_xfrm_buf to struct drm_format_conv_state
	  (Javier)
	* remove managed cleanup
	* add drm_format_conv_state_copy() for shadow-plane support

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Acked-by: default avatarNoralf Trønnes <noralf@tronnes.org>
Tested-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231009141018.11291-2-tzimmermann@suse.de
parent b0e396d6

drivers/gpu/drm/drm_format_helper.c

+107 −11
Original line number Diff line number Diff line
@@ -20,6 +20,97 @@ 
#include <drm/drm_print.h>

#include <drm/drm_rect.h>



/**

 * drm_format_conv_state_init - Initialize format-conversion state

 * @state: The state to initialize

 *

 * Clears all fields in struct drm_format_conv_state. The state will

 * be empty with no preallocated resources.

 */

void drm_format_conv_state_init(struct drm_format_conv_state *state)

{

	state->tmp.mem = NULL;

	state->tmp.size = 0;

	state->tmp.preallocated = false;

}

EXPORT_SYMBOL(drm_format_conv_state_init);



/**

 * drm_format_conv_state_copy - Copy format-conversion state

 * @state: Destination state

 * @old_state: Source state

 *

 * Copies format-conversion state from @old_state to @state; except for

 * temporary storage.

 */

void drm_format_conv_state_copy(struct drm_format_conv_state *state,

				const struct drm_format_conv_state *old_state)

{

	/*

	 * So far, there's only temporary storage here, which we don't

	 * duplicate. Just clear the fields.

	 */

	state->tmp.mem = NULL;

	state->tmp.size = 0;

	state->tmp.preallocated = false;

}

EXPORT_SYMBOL(drm_format_conv_state_copy);



/**

 * drm_format_conv_state_reserve - Allocates storage for format conversion

 * @state: The format-conversion state

 * @new_size: The minimum allocation size

 * @flags: Flags for kmalloc()

 *

 * Allocates at least @new_size bytes and returns a pointer to the memory

 * range. After calling this function, previously returned memory blocks

 * are invalid. It's best to collect all memory requirements of a format

 * conversion and call this function once to allocate the range.

 *

 * Returns:

 * A pointer to the allocated memory range, or NULL otherwise.

 */

void *drm_format_conv_state_reserve(struct drm_format_conv_state *state,

				    size_t new_size, gfp_t flags)

{

	void *mem;



	if (new_size <= state->tmp.size)

		goto out;

	else if (state->tmp.preallocated)

		return NULL;



	mem = krealloc(state->tmp.mem, new_size, flags);

	if (!mem)

		return NULL;



	state->tmp.mem = mem;

	state->tmp.size = new_size;



out:

	return state->tmp.mem;

}

EXPORT_SYMBOL(drm_format_conv_state_reserve);



/**

 * drm_format_conv_state_release - Releases an format-conversion storage

 * @state: The format-conversion state

 *

 * Releases the memory range references by the format-conversion state.

 * After this call, all pointers to the memory are invalid. Prefer

 * drm_format_conv_state_init() for cleaning up and unloading a driver.

 */

void drm_format_conv_state_release(struct drm_format_conv_state *state)

{

	if (state->tmp.preallocated)

		return;



	kfree(state->tmp.mem);

	state->tmp.mem = NULL;

	state->tmp.size = 0;

}

EXPORT_SYMBOL(drm_format_conv_state_release);



static unsigned int clip_offset(const struct drm_rect *clip, unsigned int pitch, unsigned int cpp)

{

	return clip->y1 * pitch + clip->x1 * cpp;
@@ -45,6 +136,7 @@ EXPORT_SYMBOL(drm_fb_clip_offset); 
static int __drm_fb_xfrm(void *dst, unsigned long dst_pitch, unsigned long dst_pixsize,

			 const void *vaddr, const struct drm_framebuffer *fb,

			 const struct drm_rect *clip, bool vaddr_cached_hint,

			 struct drm_format_conv_state *state,

			 void (*xfrm_line)(void *dbuf, const void *sbuf, unsigned int npixels))

{

	unsigned long linepixels = drm_rect_width(clip);
@@ -60,7 +152,7 @@ static int __drm_fb_xfrm(void *dst, unsigned long dst_pitch, unsigned long dst_p 
	 * one line at a time.

	 */

	if (!vaddr_cached_hint) {

		stmp = kmalloc(sbuf_len, GFP_KERNEL);

		stmp = drm_format_conv_state_reserve(state, sbuf_len, GFP_KERNEL);

		if (!stmp)

			return -ENOMEM;

	}
@@ -79,8 +171,6 @@ static int __drm_fb_xfrm(void *dst, unsigned long dst_pitch, unsigned long dst_p 
		dst += dst_pitch;

	}



	kfree(stmp);



	return 0;

}
@@ -88,6 +178,7 @@ static int __drm_fb_xfrm(void *dst, unsigned long dst_pitch, unsigned long dst_p 
static int __drm_fb_xfrm_toio(void __iomem *dst, unsigned long dst_pitch, unsigned long dst_pixsize,

			      const void *vaddr, const struct drm_framebuffer *fb,

			      const struct drm_rect *clip, bool vaddr_cached_hint,

			      struct drm_format_conv_state *state,

			      void (*xfrm_line)(void *dbuf, const void *sbuf, unsigned int npixels))

{

	unsigned long linepixels = drm_rect_width(clip);
@@ -101,9 +192,9 @@ static int __drm_fb_xfrm_toio(void __iomem *dst, unsigned long dst_pitch, unsign 
	void *dbuf;



	if (vaddr_cached_hint) {

		dbuf = kmalloc(dbuf_len, GFP_KERNEL);

		dbuf = drm_format_conv_state_reserve(state, dbuf_len, GFP_KERNEL);

	} else {

		dbuf = kmalloc(stmp_off + sbuf_len, GFP_KERNEL);

		dbuf = drm_format_conv_state_reserve(state, stmp_off + sbuf_len, GFP_KERNEL);

		stmp = dbuf + stmp_off;

	}

	if (!dbuf)
@@ -124,8 +215,6 @@ static int __drm_fb_xfrm_toio(void __iomem *dst, unsigned long dst_pitch, unsign 
		dst += dst_pitch;

	}



	kfree(dbuf);



	return 0;

}
@@ -139,17 +228,24 @@ static int drm_fb_xfrm(struct iosys_map *dst, 
	static const unsigned int default_dst_pitch[DRM_FORMAT_MAX_PLANES] = {

		0, 0, 0, 0

	};

	struct drm_format_conv_state fmtcnv_state = DRM_FORMAT_CONV_STATE_INIT;

	int ret;



	if (!dst_pitch)

		dst_pitch = default_dst_pitch;



	/* TODO: handle src in I/O memory here */

	if (dst[0].is_iomem)

		return __drm_fb_xfrm_toio(dst[0].vaddr_iomem, dst_pitch[0], dst_pixsize[0],

					  src[0].vaddr, fb, clip, vaddr_cached_hint, xfrm_line);

		ret = __drm_fb_xfrm_toio(dst[0].vaddr_iomem, dst_pitch[0], dst_pixsize[0],

					 src[0].vaddr, fb, clip, vaddr_cached_hint, &fmtcnv_state,

					 xfrm_line);

	else

		return __drm_fb_xfrm(dst[0].vaddr, dst_pitch[0], dst_pixsize[0],

				     src[0].vaddr, fb, clip, vaddr_cached_hint, xfrm_line);

		ret = __drm_fb_xfrm(dst[0].vaddr, dst_pitch[0], dst_pixsize[0],

				    src[0].vaddr, fb, clip, vaddr_cached_hint, &fmtcnv_state,

				    xfrm_line);

	drm_format_conv_state_release(&fmtcnv_state);



	return ret;

}



/**

include/drm/drm_format_helper.h

+51 −0
Original line number Diff line number Diff line
@@ -15,6 +15,57 @@ struct drm_rect; 


struct iosys_map;



/**

 * struct drm_format_conv_state - Stores format-conversion state

 *

 * DRM helpers for format conversion store temporary state in

 * struct drm_xfrm_buf. The buffer's resources can be reused

 * among multiple conversion operations.

 *

 * All fields are considered private.

 */

struct drm_format_conv_state {

	struct {

		void *mem;

		size_t size;

		bool preallocated;

	} tmp;

};



#define __DRM_FORMAT_CONV_STATE_INIT(_mem, _size, _preallocated) { \

		.tmp = { \

			.mem = (_mem), \

			.size = (_size), \

			.preallocated = (_preallocated), \

		} \

	}



/**

 * DRM_FORMAT_CONV_STATE_INIT - Initializer for struct drm_format_conv_state

 *

 * Initializes an instance of struct drm_format_conv_state to default values.

 */

#define DRM_FORMAT_CONV_STATE_INIT \

	__DRM_FORMAT_CONV_STATE_INIT(NULL, 0, false)



/**

 * DRM_FORMAT_CONV_STATE_INIT_PREALLOCATED - Initializer for struct drm_format_conv_state

 * @_mem: The preallocated memory area

 * @_size: The number of bytes in _mem

 *

 * Initializes an instance of struct drm_format_conv_state to preallocated

 * storage. The caller is responsible for releasing the provided memory range.

 */

#define DRM_FORMAT_CONV_STATE_INIT_PREALLOCATED(_mem, _size) \

	__DRM_FORMAT_CONV_STATE_INIT(_mem, _size, true)



void drm_format_conv_state_init(struct drm_format_conv_state *state);

void drm_format_conv_state_copy(struct drm_format_conv_state *state,

				const struct drm_format_conv_state *old_state);

void *drm_format_conv_state_reserve(struct drm_format_conv_state *state,

				    size_t new_size, gfp_t flags);

void drm_format_conv_state_release(struct drm_format_conv_state *state);



unsigned int drm_fb_clip_offset(unsigned int pitch, const struct drm_format_info *format,

				const struct drm_rect *clip);