On Tue, Jun 20, 2017 at 09:25:25PM +0200, Peter Rosin wrote:
> This makes the redundant fb helpers .load_lut, .gamma_set and .gamma_get
> totally obsolete.
>
> I think the gamma_store can end up invalid on error. But the way I read
> it, that can happen in drm_mode_gamma_set_ioctl as well, so why should
> this pesky legacy fbdev stuff be any better?
>
> drm_fb_helper_save_lut_atomic justs saves the gamma lut for later. However,
> it saves it to the gamma_store which should already be up to date with what
> .gamma_get would return and is thus a nop. So, zap it.
Removing drm_fb_helper_save_lut_atomic should be a separate patch I
think.
> Signed-off-by: Peter Rosin <peda@xxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_fb_helper.c | 131 ++++++++++++----------------------------
> 1 file changed, 40 insertions(+), 91 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
> index 574af01..cc2d55d 100644
> --- a/drivers/gpu/drm/drm_fb_helper.c
> +++ b/drivers/gpu/drm/drm_fb_helper.c
> @@ -229,22 +229,6 @@ int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
> }
> EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
>
> -static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
> -{
> - uint16_t *r_base, *g_base, *b_base;
> - int i;
> -
> - if (helper->funcs->gamma_get == NULL)
> - return;
> -
> - r_base = crtc->gamma_store;
> - g_base = r_base + crtc->gamma_size;
> - b_base = g_base + crtc->gamma_size;
> -
> - for (i = 0; i < crtc->gamma_size; i++)
> - helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
> -}
> -
> static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
> {
> uint16_t *r_base, *g_base, *b_base;
> @@ -285,7 +269,6 @@ int drm_fb_helper_debug_enter(struct fb_info *info)
> if (drm_drv_uses_atomic_modeset(mode_set->crtc->dev))
> continue;
>
> - drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
> funcs->mode_set_base_atomic(mode_set->crtc,
> mode_set->fb,
> mode_set->x,
> @@ -1167,50 +1150,6 @@ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
> }
> EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
>
> -static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
> - u16 blue, u16 regno, struct fb_info *info)
> -{
> - struct drm_fb_helper *fb_helper = info->par;
> - struct drm_framebuffer *fb = fb_helper->fb;
> -
> - if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
This case here seems gone, and it was also the pièce de résistance when I
tried tackling fbdev lut support. As far as I understand this stuff we do
not support FB_VISUAL_TRUECOLOR palette, and all that bitshifting here is
pointless. But I'm honestly not really clear.
I think removing this case should also be a separate patch, and I'd very
much prefer that someone with some fbdev-clue would ack it.
> - u32 *palette;
> - u32 value;
> - /* place color in psuedopalette */
> - if (regno > 16)
> - return -EINVAL;
> - palette = (u32 *)info->pseudo_palette;
> - red >>= (16 - info->var.red.length);
> - green >>= (16 - info->var.green.length);
> - blue >>= (16 - info->var.blue.length);
> - value = (red << info->var.red.offset) |
> - (green << info->var.green.offset) |
> - (blue << info->var.blue.offset);
> - if (info->var.transp.length > 0) {
> - u32 mask = (1 << info->var.transp.length) - 1;
> -
> - mask <<= info->var.transp.offset;
> - value |= mask;
> - }
> - palette[regno] = value;
> - return 0;
> - }
> -
> - /*
> - * The driver really shouldn't advertise pseudo/directcolor
> - * visuals if it can't deal with the palette.
> - */
> - if (WARN_ON(!fb_helper->funcs->gamma_set ||
> - !fb_helper->funcs->gamma_get))
> - return -EINVAL;
> -
> - WARN_ON(fb->format->cpp[0] != 1);
> -
> - fb_helper->funcs->gamma_set(crtc, red, green, blue, regno);
> -
> - return 0;
> -}
> -
> /**
> * drm_fb_helper_setcmap - implementation for &fb_ops.fb_setcmap
> * @cmap: cmap to set
> @@ -1220,51 +1159,61 @@ int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
> {
> struct drm_fb_helper *fb_helper = info->par;
> struct drm_device *dev = fb_helper->dev;
> - const struct drm_crtc_helper_funcs *crtc_funcs;
> - u16 *red, *green, *blue, *transp;
> + struct drm_modeset_acquire_ctx ctx;
> struct drm_crtc *crtc;
> - int i, j, rc = 0;
> - int start;
> + u16 *r, *g, *b;
> + int i, ret;
>
> if (oops_in_progress)
> return -EBUSY;
>
> - drm_modeset_lock_all(dev);
> + if (cmap->start + cmap->len < cmap->start)
> + return -EINVAL;
> +
> + drm_modeset_acquire_init(&ctx, 0);
> +retry:
> + ret = drm_modeset_lock_all_ctx(dev, &ctx);
> + if (ret)
> + goto out;
> if (!drm_fb_helper_is_bound(fb_helper)) {
> - drm_modeset_unlock_all(dev);
> - return -EBUSY;
> + ret = -EBUSY;
> + goto out;
> }
>
> for (i = 0; i < fb_helper->crtc_count; i++) {
> crtc = fb_helper->crtc_info[i].mode_set.crtc;
> - crtc_funcs = crtc->helper_private;
> -
> - red = cmap->red;
> - green = cmap->green;
> - blue = cmap->blue;
> - transp = cmap->transp;
> - start = cmap->start;
> + if (!crtc->funcs->gamma_set || !crtc->gamma_size) {
> + ret = -EINVAL;
> + goto out;
> + }
>
> - for (j = 0; j < cmap->len; j++) {
> - u16 hred, hgreen, hblue, htransp = 0xffff;
> + if (cmap->start + cmap->len > crtc->gamma_size) {
> + ret = -EINVAL;
> + goto out;
> + }
>
> - hred = *red++;
> - hgreen = *green++;
> - hblue = *blue++;
> + r = crtc->gamma_store;
> + g = r + crtc->gamma_size;
> + b = g + crtc->gamma_size;
>
> - if (transp)
> - htransp = *transp++;
> + memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(u16));
> + memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(u16));
> + memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(u16));
>
> - rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
> - if (rc)
> - goto out;
> - }
> - if (crtc_funcs->load_lut)
> - crtc_funcs->load_lut(crtc);
> + ret = crtc->funcs->gamma_set(crtc, r, g, b,
> + crtc->gamma_size, &ctx);
> + if (ret)
> + break;
> }
> - out:
> - drm_modeset_unlock_all(dev);
> - return rc;
> +out:
> + if (ret == -EDEADLK) {
> + drm_modeset_backoff(&ctx);
> + goto retry;
> + }
> + drm_modeset_drop_locks(&ctx);
> + drm_modeset_acquire_fini(&ctx);
> +
> + return ret;
It's a pre-existing bug, but should we also try to restore the fbdev lut
in drm_fb_helper_restore_fbdev_mode_unlocked()? Would be yet another bug,
but might be relevant for your use-case. Just try to run both an fbdev
application and some kms-native thing, and then SIGKILL the native kms
app.
But since pre-existing not really required, and probably too much effort.
Thanks, Daniel
> }
> EXPORT_SYMBOL(drm_fb_helper_setcmap);
>
> --
> 2.1.4
>
> _______________________________________________
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> dri-devel@xxxxxxxxxxxxxxxxxxxxx
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
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