drm/fb: rename FB CMA helpers to FB DMA helpers

Rename "FB CMA" helpers to "FB DMA" helpers - considering the hierarchy
of APIs (mm/cma -> dma -> fb dma) calling them "FB DMA" seems to be
more applicable.

Besides that, commit e57924d4ae80 ("drm/doc: Task to rename CMA helpers")
requests to rename the CMA helpers and implies that people seem to be
confused about the naming.

In order to do this renaming the following script was used:

```
	#!/bin/bash

	DIRS="drivers/gpu include/drm Documentation/gpu"

	REGEX_SYM_UPPER="[0-9A-Z_\-]"
	REGEX_SYM_LOWER="[0-9a-z_\-]"

	REGEX_GREP_UPPER="(${REGEX_SYM_UPPER}*)(FB)_CMA_(${REGEX_SYM_UPPER}*)"
	REGEX_GREP_LOWER="(${REGEX_SYM_LOWER}*)(fb)_cma_(${REGEX_SYM_LOWER}*)"

	REGEX_SED_UPPER="s/${REGEX_GREP_UPPER}/\1\2_DMA_\3/g"
	REGEX_SED_LOWER="s/${REGEX_GREP_LOWER}/\1\2_dma_\3/g"

	# Find all upper case 'CMA' symbols and replace them with 'DMA'.
	for ff in $(grep -REHl "${REGEX_GREP_UPPER}" $DIRS)
	do
	       sed -i -E "$REGEX_SED_UPPER" $ff
	done

	# Find all lower case 'cma' symbols and replace them with 'dma'.
	for ff in $(grep -REHl "${REGEX_GREP_LOWER}" $DIRS)
	do
	       sed -i -E "$REGEX_SED_LOWER" $ff
	done

	# Replace all occurrences of 'CMA' / 'cma' in comments and
	# documentation files with 'DMA' / 'dma'.
	for ff in $(grep -RiHl " cma " $DIRS)
	do
		sed -i -E "s/ cma / dma /g" $ff
		sed -i -E "s/ CMA / DMA /g" $ff
	done
```

Only a few more manual modifications were needed, e.g. reverting the
following modifications in some DRM Kconfig files

    -       select CMA if HAVE_DMA_CONTIGUOUS
    +       select DMA if HAVE_DMA_CONTIGUOUS

as well as manually picking the occurrences of 'CMA'/'cma' in comments and
documentation which relate to "FB CMA", but not "GEM CMA".

This patch is compile-time tested building a x86_64 kernel with
`make allyesconfig && make drivers/gpu/drm`.

Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com> #drivers/gpu/drm/arm
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220802000405.949236-3-dakr@redhat.com

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c
index c6182b5de78b..400b16d9147d 100644
--- a/drivers/gpu/drm/drm_format_helper.c
+++ b/drivers/gpu/drm/drm_format_helper.c
@@ -54,7 +54,7 @@ static int drm_fb_xfrm(void *dst, unsigned long dst_pitch, unsigned long dst_pix
 	const void *sbuf;
 
 	/*
-	 * Some source buffers, such as CMA memory, use write-combine
+	 * Some source buffers, such as DMA memory, use write-combine
 	 * caching, so reads are uncached. Speed up access by fetching
 	 * one line at a time.
 	 */
@@ -676,7 +676,7 @@ void drm_fb_xrgb8888_to_mono(void *dst, unsigned int dst_pitch, const void *vadd
 		dst_pitch = DIV_ROUND_UP(linepixels, 8);
 
 	/*
-	 * The cma memory is write-combined so reads are uncached.
+	 * The dma memory is write-combined so reads are uncached.
 	 * Speed up by fetching one line at a time.
 	 *
 	 * Also, format conversion from XR24 to monochrome are done