blob: 775b97766e08f41ec1132e1a2c236593bde61a3b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
#include <linux/crc32.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_vblank.h>
#include "vkms_drv.h"
static u32 get_pixel_from_buffer(int x, int y, const u8 *buffer,
const struct vkms_composer *composer)
{
u32 pixel;
int src_offset = composer->offset + (y * composer->pitch)
+ (x * composer->cpp);
pixel = *(u32 *)&buffer[src_offset];
return pixel;
}
/**
* compute_crc - Compute CRC value on output frame
*
* @vaddr: address to final framebuffer
* @composer: framebuffer's metadata
*
* returns CRC value computed using crc32 on the visible portion of
* the final framebuffer at vaddr_out
*/
static uint32_t compute_crc(const u8 *vaddr,
const struct vkms_composer *composer)
{
int x, y;
u32 crc = 0, pixel = 0;
int x_src = composer->src.x1 >> 16;
int y_src = composer->src.y1 >> 16;
int h_src = drm_rect_height(&composer->src) >> 16;
int w_src = drm_rect_width(&composer->src) >> 16;
for (y = y_src; y < y_src + h_src; ++y) {
for (x = x_src; x < x_src + w_src; ++x) {
pixel = get_pixel_from_buffer(x, y, vaddr, composer);
crc = crc32_le(crc, (void *)&pixel, sizeof(u32));
}
}
return crc;
}
static u8 blend_channel(u8 src, u8 dst, u8 alpha)
{
u32 pre_blend;
u8 new_color;
pre_blend = (src * 255 + dst * (255 - alpha));
/* Faster div by 255 */
new_color = ((pre_blend + ((pre_blend + 257) >> 8)) >> 8);
return new_color;
}
/**
* alpha_blend - alpha blending equation
* @argb_src: src pixel on premultiplied alpha mode
* @argb_dst: dst pixel completely opaque
*
* blend pixels using premultiplied blend formula. The current DRM assumption
* is that pixel color values have been already pre-multiplied with the alpha
* channel values. See more drm_plane_create_blend_mode_property(). Also, this
* formula assumes a completely opaque background.
*/
static void alpha_blend(const u8 *argb_src, u8 *argb_dst)
{
u8 alpha;
alpha = argb_src[3];
argb_dst[0] = blend_channel(argb_src[0], argb_dst[0], alpha);
argb_dst[1] = blend_channel(argb_src[1], argb_dst[1], alpha);
argb_dst[2] = blend_channel(argb_src[2], argb_dst[2], alpha);
}
/**
* x_blend - blending equation that ignores the pixel alpha
*
* overwrites RGB color value from src pixel to dst pixel.
*/
static void x_blend(const u8 *xrgb_src, u8 *xrgb_dst)
{
memcpy(xrgb_dst, xrgb_src, sizeof(u8) * 3);
}
/**
* blend - blend value at vaddr_src with value at vaddr_dst
* @vaddr_dst: destination address
* @vaddr_src: source address
* @dst_composer: destination framebuffer's metadata
* @src_composer: source framebuffer's metadata
* @pixel_blend: blending equation based on plane format
*
* Blend the vaddr_src value with the vaddr_dst value using a pixel blend
* equation according to the supported plane formats DRM_FORMAT_(A/XRGB8888)
* and clearing alpha channel to an completely opaque background. This function
* uses buffer's metadata to locate the new composite values at vaddr_dst.
*
* TODO: completely clear the primary plane (a = 0xff) before starting to blend
* pixel color values
*/
static void blend(void *vaddr_dst, void *vaddr_src,
struct vkms_composer *dst_composer,
struct vkms_composer *src_composer,
void (*pixel_blend)(const u8 *, u8 *))
{
int i, j, j_dst, i_dst;
int offset_src, offset_dst;
u8 *pixel_dst, *pixel_src;
int x_src = src_composer->src.x1 >> 16;
int y_src = src_composer->src.y1 >> 16;
int x_dst = src_composer->dst.x1;
int y_dst = src_composer->dst.y1;
int h_dst = drm_rect_height(&src_composer->dst);
int w_dst = drm_rect_width(&src_composer->dst);
int y_limit = y_src + h_dst;
int x_limit = x_src + w_dst;
for (i = y_src, i_dst = y_dst; i < y_limit; ++i) {
for (j = x_src, j_dst = x_dst; j < x_limit; ++j) {
offset_dst = dst_composer->offset
+ (i_dst * dst_composer->pitch)
+ (j_dst++ * dst_composer->cpp);
offset_src = src_composer->offset
+ (i * src_composer->pitch)
+ (j * src_composer->cpp);
pixel_src = (u8 *)(vaddr_src + offset_src);
pixel_dst = (u8 *)(vaddr_dst + offset_dst);
pixel_blend(pixel_src, pixel_dst);
/* clearing alpha channel (0xff)*/
pixel_dst[3] = 0xff;
}
i_dst++;
}
}
static void compose_plane(struct vkms_composer *primary_composer,
struct vkms_composer *plane_composer,
void *vaddr_out)
{
struct drm_framebuffer *fb = &plane_composer->fb;
void *vaddr;
void (*pixel_blend)(const u8 *p_src, u8 *p_dst);
if (WARN_ON(iosys_map_is_null(&plane_composer->map[0])))
return;
vaddr = plane_composer->map[0].vaddr;
if (fb->format->format == DRM_FORMAT_ARGB8888)
pixel_blend = &alpha_blend;
else
pixel_blend = &x_blend;
blend(vaddr_out, vaddr, primary_composer, plane_composer, pixel_blend);
}
static int compose_active_planes(void **vaddr_out,
struct vkms_composer *primary_composer,
struct vkms_crtc_state *crtc_state)
{
struct drm_framebuffer *fb = &primary_composer->fb;
struct drm_gem_object *gem_obj = drm_gem_fb_get_obj(fb, 0);
const void *vaddr;
int i;
if (!*vaddr_out) {
*vaddr_out = kvzalloc(gem_obj->size, GFP_KERNEL);
if (!*vaddr_out) {
DRM_ERROR("Cannot allocate memory for output frame.");
return -ENOMEM;
}
}
if (WARN_ON(iosys_map_is_null(&primary_composer->map[0])))
return -EINVAL;
vaddr = primary_composer->map[0].vaddr;
memcpy(*vaddr_out, vaddr, gem_obj->size);
/* If there are other planes besides primary, we consider the active
* planes should be in z-order and compose them associatively:
* ((primary <- overlay) <- cursor)
*/
for (i = 1; i < crtc_state->num_active_planes; i++)
compose_plane(primary_composer,
crtc_state->active_planes[i]->composer,
*vaddr_out);
return 0;
}
/**
* vkms_composer_worker - ordered work_struct to compute CRC
*
* @work: work_struct
*
* Work handler for composing and computing CRCs. work_struct scheduled in
* an ordered workqueue that's periodically scheduled to run by
* vkms_vblank_simulate() and flushed at vkms_atomic_commit_tail().
*/
void vkms_composer_worker(struct work_struct *work)
{
struct vkms_crtc_state *crtc_state = container_of(work,
struct vkms_crtc_state,
composer_work);
struct drm_crtc *crtc = crtc_state->base.crtc;
struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
struct vkms_composer *primary_composer = NULL;
struct vkms_plane_state *act_plane = NULL;
bool crc_pending, wb_pending;
void *vaddr_out = NULL;
u32 crc32 = 0;
u64 frame_start, frame_end;
int ret;
spin_lock_irq(&out->composer_lock);
frame_start = crtc_state->frame_start;
frame_end = crtc_state->frame_end;
crc_pending = crtc_state->crc_pending;
wb_pending = crtc_state->wb_pending;
crtc_state->frame_start = 0;
crtc_state->frame_end = 0;
crtc_state->crc_pending = false;
spin_unlock_irq(&out->composer_lock);
/*
* We raced with the vblank hrtimer and previous work already computed
* the crc, nothing to do.
*/
if (!crc_pending)
return;
if (crtc_state->num_active_planes >= 1) {
act_plane = crtc_state->active_planes[0];
if (act_plane->base.base.plane->type == DRM_PLANE_TYPE_PRIMARY)
primary_composer = act_plane->composer;
}
if (!primary_composer)
return;
if (wb_pending)
vaddr_out = crtc_state->active_writeback->data[0].vaddr;
ret = compose_active_planes(&vaddr_out, primary_composer,
crtc_state);
if (ret) {
if (ret == -EINVAL && !wb_pending)
kvfree(vaddr_out);
return;
}
crc32 = compute_crc(vaddr_out, primary_composer);
if (wb_pending) {
drm_writeback_signal_completion(&out->wb_connector, 0);
spin_lock_irq(&out->composer_lock);
crtc_state->wb_pending = false;
spin_unlock_irq(&out->composer_lock);
} else {
kvfree(vaddr_out);
}
/*
* The worker can fall behind the vblank hrtimer, make sure we catch up.
*/
while (frame_start <= frame_end)
drm_crtc_add_crc_entry(crtc, true, frame_start++, &crc32);
}
static const char * const pipe_crc_sources[] = {"auto"};
const char *const *vkms_get_crc_sources(struct drm_crtc *crtc,
size_t *count)
{
*count = ARRAY_SIZE(pipe_crc_sources);
return pipe_crc_sources;
}
static int vkms_crc_parse_source(const char *src_name, bool *enabled)
{
int ret = 0;
if (!src_name) {
*enabled = false;
} else if (strcmp(src_name, "auto") == 0) {
*enabled = true;
} else {
*enabled = false;
ret = -EINVAL;
}
return ret;
}
int vkms_verify_crc_source(struct drm_crtc *crtc, const char *src_name,
size_t *values_cnt)
{
bool enabled;
if (vkms_crc_parse_source(src_name, &enabled) < 0) {
DRM_DEBUG_DRIVER("unknown source %s\n", src_name);
return -EINVAL;
}
*values_cnt = 1;
return 0;
}
void vkms_set_composer(struct vkms_output *out, bool enabled)
{
bool old_enabled;
if (enabled)
drm_crtc_vblank_get(&out->crtc);
spin_lock_irq(&out->lock);
old_enabled = out->composer_enabled;
out->composer_enabled = enabled;
spin_unlock_irq(&out->lock);
if (old_enabled)
drm_crtc_vblank_put(&out->crtc);
}
int vkms_set_crc_source(struct drm_crtc *crtc, const char *src_name)
{
struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
bool enabled = false;
int ret = 0;
ret = vkms_crc_parse_source(src_name, &enabled);
vkms_set_composer(out, enabled);
return ret;
}