drm/vc4: kms: Remove unassigned_channels from the HVS state

The HVS state now has both unassigned_channels that reflects the
channels that are not used in the associated state, and the in_use
boolean for each channel that says whether or not a particular channel
is in use.

Both express pretty much the same thing, and we need the in_use variable
to properly track the commits, so let's get rid of unassigned_channels.

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201204151138.1739736-6-maxime@cerno.tech

diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c
index fdd698d..5d81b90 100644 (file)
--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -39,7 +39,6 @@ static struct vc4_ctm_state *to_vc4_ctm_state(struct drm_private_state *priv)
 
 struct vc4_hvs_state {
        struct drm_private_state base;
-       unsigned int unassigned_channels;
 
        struct {
                unsigned in_use: 1;
@@ -798,7 +797,6 @@ vc4_hvs_channels_duplicate_state(struct drm_private_obj *obj)
 
        __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base);
 
-       state->unassigned_channels = old_state->unassigned_channels;
 
        for (i = 0; i < HVS_NUM_CHANNELS; i++) {
                state->fifo_state[i].in_use = old_state->fifo_state[i].in_use;
@@ -849,7 +847,6 @@ static int vc4_hvs_channels_obj_init(struct vc4_dev *vc4)
        if (!state)
                return -ENOMEM;
 
-       state->unassigned_channels = GENMASK(HVS_NUM_CHANNELS - 1, 0);
        drm_atomic_private_obj_init(&vc4->base, &vc4->hvs_channels,
                                    &state->base,
                                    &vc4_hvs_state_funcs);
@@ -893,12 +890,17 @@ static int vc4_pv_muxing_atomic_check(struct drm_device *dev,
        struct vc4_hvs_state *hvs_new_state;
        struct drm_crtc_state *old_crtc_state, *new_crtc_state;
        struct drm_crtc *crtc;
+       unsigned int unassigned_channels = 0;
        unsigned int i;
 
        hvs_new_state = vc4_hvs_get_global_state(state);
        if (!hvs_new_state)
                return -EINVAL;
 
+       for (i = 0; i < ARRAY_SIZE(hvs_new_state->fifo_state); i++)
+               if (!hvs_new_state->fifo_state[i].in_use)
+                       unassigned_channels |= BIT(i);
+
        for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
                struct vc4_crtc_state *old_vc4_crtc_state =
                        to_vc4_crtc_state(old_crtc_state);
@@ -918,8 +920,6 @@ static int vc4_pv_muxing_atomic_check(struct drm_device *dev,
                /* If we're disabling our CRTC, we put back our channel */
                if (!new_crtc_state->enable) {
                        channel = old_vc4_crtc_state->assigned_channel;
-
-                       hvs_new_state->unassigned_channels |= BIT(channel);
                        hvs_new_state->fifo_state[channel].in_use = false;
                        new_vc4_crtc_state->assigned_channel = VC4_HVS_CHANNEL_DISABLED;
                        continue;
@@ -949,13 +949,13 @@ static int vc4_pv_muxing_atomic_check(struct drm_device *dev,
                 * the future, we will need to have something smarter,
                 * but it works so far.
                 */
-               matching_channels = hvs_new_state->unassigned_channels & vc4_crtc->data->hvs_available_channels;
+               matching_channels = unassigned_channels & vc4_crtc->data->hvs_available_channels;
                if (!matching_channels)
                        return -EINVAL;
 
                channel = ffs(matching_channels) - 1;
                new_vc4_crtc_state->assigned_channel = channel;
-               hvs_new_state->unassigned_channels &= ~BIT(channel);
+               unassigned_channels &= ~BIT(channel);
                hvs_new_state->fifo_state[channel].in_use = true;
        }