drm: vkms: Add support to the RGB565 format

This commit also adds new helper macros to deal with fixed-point
arithmetic.

It was done to improve the precision of the conversion to ARGB16161616
since the "conversion ratio" is not an integer.

V3: Adapt the handlers to the new format introduced in patch 7 V3.
V5: Minor improvements
V6: Minor improvements (Pekka Paalanen)

Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
Signed-off-by: Melissa Wen <melissa.srw@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220905190811.25024-10-igormtorrente@gmail.com
This commit is contained in:
Igor Torrente 2022-09-05 16:08:11 -03:00 committed by Melissa Wen
parent 3675d8a172
commit 396369d675
3 changed files with 76 additions and 3 deletions

View file

@ -5,6 +5,23 @@
#include "vkms_formats.h"
/* The following macros help doing fixed point arithmetic. */
/*
* With Fixed-Point scale 15 we have 17 and 15 bits of integer and fractional
* parts respectively.
* | 0000 0000 0000 0000 0.000 0000 0000 0000 |
* 31 0
*/
#define SHIFT 15
#define INT_TO_FIXED(a) ((a) << SHIFT)
#define FIXED_MUL(a, b) ((s32)(((s64)(a) * (b)) >> SHIFT))
#define FIXED_DIV(a, b) ((s32)(((s64)(a) << SHIFT) / (b)))
/* This macro converts a fixed point number to int, and round half up it */
#define FIXED_TO_INT_ROUND(a) (((a) + (1 << (SHIFT - 1))) >> SHIFT)
#define INT_TO_FIXED_DIV(a, b) (FIXED_DIV(INT_TO_FIXED(a), INT_TO_FIXED(b)))
#define INT_TO_FIXED_DIV(a, b) (FIXED_DIV(INT_TO_FIXED(a), INT_TO_FIXED(b)))
static size_t pixel_offset(const struct vkms_frame_info *frame_info, int x, int y)
{
return frame_info->offset + (y * frame_info->pitch)
@ -112,6 +129,30 @@ static void XRGB16161616_to_argb_u16(struct line_buffer *stage_buffer,
}
}
static void RGB565_to_argb_u16(struct line_buffer *stage_buffer,
const struct vkms_frame_info *frame_info, int y)
{
struct pixel_argb_u16 *out_pixels = stage_buffer->pixels;
u16 *src_pixels = get_packed_src_addr(frame_info, y);
int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
stage_buffer->n_pixels);
s32 fp_rb_ratio = INT_TO_FIXED_DIV(65535, 31);
s32 fp_g_ratio = INT_TO_FIXED_DIV(65535, 63);
for (size_t x = 0; x < x_limit; x++, src_pixels++) {
u16 rgb_565 = le16_to_cpu(*src_pixels);
s32 fp_r = INT_TO_FIXED((rgb_565 >> 11) & 0x1f);
s32 fp_g = INT_TO_FIXED((rgb_565 >> 5) & 0x3f);
s32 fp_b = INT_TO_FIXED(rgb_565 & 0x1f);
out_pixels[x].a = (u16)0xffff;
out_pixels[x].r = FIXED_TO_INT_ROUND(FIXED_MUL(fp_r, fp_rb_ratio));
out_pixels[x].g = FIXED_TO_INT_ROUND(FIXED_MUL(fp_g, fp_g_ratio));
out_pixels[x].b = FIXED_TO_INT_ROUND(FIXED_MUL(fp_b, fp_rb_ratio));
}
}
/*
* The following functions take an line of argb_u16 pixels from the
* src_buffer, convert them to a specific format, and store them in the
@ -198,6 +239,31 @@ static void argb_u16_to_XRGB16161616(struct vkms_frame_info *frame_info,
}
}
static void argb_u16_to_RGB565(struct vkms_frame_info *frame_info,
const struct line_buffer *src_buffer, int y)
{
int x_dst = frame_info->dst.x1;
u16 *dst_pixels = packed_pixels_addr(frame_info, x_dst, y);
struct pixel_argb_u16 *in_pixels = src_buffer->pixels;
int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
src_buffer->n_pixels);
s32 fp_rb_ratio = INT_TO_FIXED_DIV(65535, 31);
s32 fp_g_ratio = INT_TO_FIXED_DIV(65535, 63);
for (size_t x = 0; x < x_limit; x++, dst_pixels++) {
s32 fp_r = INT_TO_FIXED(in_pixels[x].r);
s32 fp_g = INT_TO_FIXED(in_pixels[x].g);
s32 fp_b = INT_TO_FIXED(in_pixels[x].b);
u16 r = FIXED_TO_INT_ROUND(FIXED_DIV(fp_r, fp_rb_ratio));
u16 g = FIXED_TO_INT_ROUND(FIXED_DIV(fp_g, fp_g_ratio));
u16 b = FIXED_TO_INT_ROUND(FIXED_DIV(fp_b, fp_rb_ratio));
*dst_pixels = cpu_to_le16(r << 11 | g << 5 | b);
}
}
void *get_frame_to_line_function(u32 format)
{
switch (format) {
@ -209,6 +275,8 @@ void *get_frame_to_line_function(u32 format)
return &ARGB16161616_to_argb_u16;
case DRM_FORMAT_XRGB16161616:
return &XRGB16161616_to_argb_u16;
case DRM_FORMAT_RGB565:
return &RGB565_to_argb_u16;
default:
return NULL;
}
@ -225,6 +293,8 @@ void *get_line_to_frame_function(u32 format)
return &argb_u16_to_ARGB16161616;
case DRM_FORMAT_XRGB16161616:
return &argb_u16_to_XRGB16161616;
case DRM_FORMAT_RGB565:
return &argb_u16_to_RGB565;
default:
return NULL;
}

View file

@ -13,14 +13,16 @@
static const u32 vkms_formats[] = {
DRM_FORMAT_XRGB8888,
DRM_FORMAT_XRGB16161616
DRM_FORMAT_XRGB16161616,
DRM_FORMAT_RGB565
};
static const u32 vkms_plane_formats[] = {
DRM_FORMAT_ARGB8888,
DRM_FORMAT_XRGB8888,
DRM_FORMAT_XRGB16161616,
DRM_FORMAT_ARGB16161616
DRM_FORMAT_ARGB16161616,
DRM_FORMAT_RGB565
};
static struct drm_plane_state *

View file

@ -17,7 +17,8 @@
static const u32 vkms_wb_formats[] = {
DRM_FORMAT_XRGB8888,
DRM_FORMAT_XRGB16161616,
DRM_FORMAT_ARGB16161616
DRM_FORMAT_ARGB16161616,
DRM_FORMAT_RGB565
};
static const struct drm_connector_funcs vkms_wb_connector_funcs = {