modesetting: Use atomic modesetting API for pageflip if available

In order to flip between compressed and uncompressed buffers -
something drmModePageFlip explicitly bans us from doing - we need
to port use the atomic modesetting API. It's only 'fake' atomic
though given we still commit for each CRTC separately and
CRTC and connector properties are not set with the atomic API.

The helper functions to retrieve DRM properties have been borrowed
from Weston.

Signed-off-by: Louis-Francis Ratté-Boulianne <lfrb@collabora.com>

7 files changed, 435 insertions, 4 deletions

diff --git a/configure.ac b/configure.ac
index 9ab0ce597..6c4c54796 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2108,6 +2108,9 @@ if test "x$GLAMOR" = xyes; then
 		fi
 	fi
 
+	PKG_CHECK_EXISTS(libdrm >= 2.4.62,
+			 [AC_DEFINE(GLAMOR_HAS_DRM_ATOMIC, 1, [libdrm supports atomic API])],
+			 [])
 	PKG_CHECK_EXISTS(libdrm >= 2.4.74,
 			 [AC_DEFINE(GLAMOR_HAS_DRM_NAME_FROM_FD_2, 1, [Have GLAMOR_HAS_DRM_NAME_FROM_FD_2])],
 			 [])
diff --git a/hw/xfree86/drivers/modesetting/driver.c b/hw/xfree86/drivers/modesetting/driver.c
index 21e75c762..5ce1de037 100644
--- a/hw/xfree86/drivers/modesetting/driver.c
+++ b/hw/xfree86/drivers/modesetting/driver.c
@@ -1023,6 +1023,12 @@ PreInit(ScrnInfoPtr pScrn, int flags)
     }
 #endif
 
+#ifdef GLAMOR_HAS_DRM_ATOMIC
+    ret = drmSetClientCap(ms->fd, DRM_CLIENT_CAP_UNIVERSAL_PLANES, 1);
+    ret |= drmSetClientCap(ms->fd, DRM_CLIENT_CAP_ATOMIC, 1);
+    ms->atomic_modeset = (ret == 0);
+#endif
+
     if (drmmode_pre_init(pScrn, &ms->drmmode, pScrn->bitsPerPixel / 8) == FALSE) {
         xf86DrvMsg(pScrn->scrnIndex, X_ERROR, "KMS setup failed\n");
         goto fail;
diff --git a/hw/xfree86/drivers/modesetting/driver.h b/hw/xfree86/drivers/modesetting/driver.h
index bfdc66c89..09ffeea5e 100644
--- a/hw/xfree86/drivers/modesetting/driver.h
+++ b/hw/xfree86/drivers/modesetting/driver.h
@@ -105,6 +105,7 @@ typedef struct _modesettingRec {
      * Page flipping stuff.
      *  @{
      */
+    Bool atomic_modeset;
     /** @} */
 
     DamagePtr damage;
diff --git a/hw/xfree86/drivers/modesetting/drmmode_display.c b/hw/xfree86/drivers/modesetting/drmmode_display.c
index b5a03256e..4fed593ba 100644
--- a/hw/xfree86/drivers/modesetting/drmmode_display.c
+++ b/hw/xfree86/drivers/modesetting/drmmode_display.c
@@ -87,6 +87,233 @@ drmmode_zaphod_string_matches(ScrnInfoPtr scrn, const char *s, char *output_name
     return FALSE;
 }
 
+static uint64_t
+drmmode_prop_get_value(drmmode_prop_info_ptr info,
+                       drmModeObjectPropertiesPtr props,
+                       uint64_t def)
+{
+    unsigned int i;
+
+    if (info->prop_id == 0)
+        return def;
+
+    for (i = 0; i < props->count_props; i++) {
+        unsigned int j;
+
+        if (props->props[i] != info->prop_id)
+            continue;
+
+        /* Simple (non-enum) types can return the value directly */
+        if (info->num_enum_values == 0)
+            return props->prop_values[i];
+
+        /* Map from raw value to enum value */
+        for (j = 0; j < info->num_enum_values; j++) {
+            if (!info->enum_values[j].valid)
+                continue;
+            if (info->enum_values[j].value != props->prop_values[i])
+                continue;
+
+            return j;
+        }
+    }
+
+    return def;
+}
+
+static uint32_t
+drmmode_prop_info_update(drmmode_ptr drmmode,
+                         drmmode_prop_info_ptr info,
+                         unsigned int num_infos,
+                         drmModeObjectProperties *props)
+{
+    drmModePropertyRes *prop;
+    uint32_t valid_mask = 0;
+    unsigned i, j;
+
+    assert(num_infos <= 32 && "update return type");
+
+    for (i = 0; i < props->count_props; i++) {
+        Bool props_incomplete = FALSE;
+        unsigned int k;
+
+        for (j = 0; j < num_infos; j++) {
+            if (info[j].prop_id == props->props[i])
+                break;
+            if (!info[j].prop_id)
+                props_incomplete = TRUE;
+        }
+
+        /* We've already discovered this property. */
+        if (j != num_infos)
+            continue;
+
+        /* We haven't found this property ID, but as we've already
+         * found all known properties, we don't need to look any
+         * further. */
+        if (!props_incomplete)
+            break;
+
+        prop = drmModeGetProperty(drmmode->fd, props->props[i]);
+        if (!prop)
+            continue;
+
+        for (j = 0; j < num_infos; j++) {
+            if (!strcmp(prop->name, info[j].name))
+                break;
+        }
+
+        /* We don't know/care about this property. */
+        if (j == num_infos) {
+            drmModeFreeProperty(prop);
+            continue;
+        }
+
+        info[j].prop_id = props->props[i];
+        valid_mask |= 1U << j;
+
+        if (info[j].num_enum_values == 0) {
+            drmModeFreeProperty(prop);
+            continue;
+        }
+
+        if (!(prop->flags & DRM_MODE_PROP_ENUM)) {
+            xf86DrvMsg(drmmode->scrn->scrnIndex, X_WARNING,
+                       "expected property %s to be an enum,"
+                       " but it is not; ignoring\n", prop->name);
+            drmModeFreeProperty(prop);
+            continue;
+        }
+
+        for (k = 0; k < info[j].num_enum_values; k++) {
+            int l;
+
+            if (info[j].enum_values[k].valid)
+                continue;
+
+            for (l = 0; l < prop->count_enums; l++) {
+                if (!strcmp(prop->enums[l].name,
+                            info[j].enum_values[k].name))
+                    break;
+            }
+
+            if (l == prop->count_enums)
+                continue;
+
+            info[j].enum_values[k].valid = TRUE;
+            info[j].enum_values[k].value = prop->enums[l].value;
+        }
+
+        drmModeFreeProperty(prop);
+    }
+
+    return valid_mask;
+}
+
+static Bool
+drmmode_prop_info_copy(drmmode_prop_info_ptr dst,
+		       const drmmode_prop_info_rec *src,
+		       unsigned int num_props,
+		       Bool copy_prop_id)
+{
+    unsigned int i;
+
+    memcpy(dst, src, num_props * sizeof(*dst));
+
+    for (i = 0; i < num_props; i++) {
+        unsigned int j;
+
+        if (copy_prop_id)
+            dst[i].prop_id = src[i].prop_id;
+        else
+            dst[i].prop_id = 0;
+
+        if (src[i].num_enum_values == 0)
+            continue;
+
+        dst[i].enum_values =
+            malloc(src[i].num_enum_values *
+                    sizeof(*dst[i].enum_values));
+        if (!dst[i].enum_values)
+            goto err;
+
+        memcpy(dst[i].enum_values, src[i].enum_values,
+                src[i].num_enum_values * sizeof(*dst[i].enum_values));
+
+        for (j = 0; j < dst[i].num_enum_values; j++)
+            dst[i].enum_values[j].valid = FALSE;
+    }
+
+    return TRUE;
+
+err:
+    while (i--)
+        free(dst[i].enum_values);
+    free(dst);
+    return FALSE;
+}
+
+static void
+drmmode_prop_info_free(drmmode_prop_info_ptr info, int num_props)
+{
+    int i;
+
+    for (i = 0; i < num_props; i++)
+        free(info[i].enum_values);
+}
+
+#ifdef GLAMOR_HAS_DRM_ATOMIC
+static int
+plane_add_prop(drmModeAtomicReq *req, drmmode_crtc_private_ptr drmmode_crtc,
+               enum drmmode_plane_property prop, uint64_t val)
+{
+    drmmode_prop_info_ptr info = &drmmode_crtc->props_plane[prop];
+    int ret;
+
+    if (!info)
+        return -1;
+
+    ret = drmModeAtomicAddProperty(req, drmmode_crtc->plane_id,
+                                   info->prop_id, val);
+    return (ret <= 0) ? -1 : 0;
+}
+#endif
+
+int
+drmmode_crtc_set_fb(xf86CrtcPtr crtc, uint32_t fb_id,
+                    int x, int y, uint32_t flags, void *data)
+{
+    modesettingPtr ms = modesettingPTR(crtc->scrn);
+    xf86CrtcConfigPtr xf86_config = XF86_CRTC_CONFIG_PTR(crtc->scrn);
+    drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
+    int ret = 0;
+
+#ifdef GLAMOR_HAS_DRM_ATOMIC
+    if (ms->atomic_modeset) {
+        drmModeAtomicReq *req = drmModeAtomicAlloc();
+
+        if (!req)
+            return 1;
+
+        ret |= plane_add_prop(req, drmmode_crtc, DRMMODE_PLANE_FB_ID,
+                              fb_id);
+        ret |= plane_add_prop(req, drmmode_crtc, DRMMODE_PLANE_CRTC_ID,
+                              drmmode_crtc->mode_crtc->crtc_id);
+        ret |= plane_add_prop(req, drmmode_crtc, DRMMODE_PLANE_SRC_X, x);
+        ret |= plane_add_prop(req, drmmode_crtc, DRMMODE_PLANE_SRC_Y, y);
+
+        if (ret == 0)
+            ret = drmModeAtomicCommit(ms->fd, req, flags, data);
+
+        drmModeAtomicFree(req);
+        return ret;
+    }
+#endif
+
+    return 0;
+}
+
+
 int
 drmmode_bo_destroy(drmmode_ptr drmmode, drmmode_bo *bo)
 {
@@ -1097,6 +1324,14 @@ drmmode_shadow_destroy(xf86CrtcPtr crtc, PixmapPtr rotate_pixmap, void *data)
     }
 }
 
+static void
+drmmode_crtc_destroy(xf86CrtcPtr crtc)
+{
+    drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
+
+    drmmode_prop_info_free(drmmode_crtc->props_plane, DRMMODE_PLANE__COUNT);
+}
+
 static const xf86CrtcFuncsRec drmmode_crtc_funcs = {
     .dpms = drmmode_crtc_dpms,
     .set_mode_major = drmmode_set_mode_major,
@@ -1107,7 +1342,7 @@ static const xf86CrtcFuncsRec drmmode_crtc_funcs = {
     .load_cursor_argb_check = drmmode_load_cursor_argb_check,
 
     .gamma_set = drmmode_crtc_gamma_set,
-    .destroy = NULL,            /* XXX */
+    .destroy = drmmode_crtc_destroy,
     .set_scanout_pixmap = drmmode_set_scanout_pixmap,
     .shadow_allocate = drmmode_shadow_allocate,
     .shadow_create = drmmode_shadow_create,
@@ -1125,6 +1360,132 @@ drmmode_crtc_vblank_pipe(int crtc_id)
         return 0;
 }
 
+#ifdef GLAMOR_HAS_DRM_ATOMIC
+static Bool
+is_plane_assigned(ScrnInfoPtr scrn, int plane_id)
+{
+    xf86CrtcConfigPtr xf86_config = XF86_CRTC_CONFIG_PTR(scrn);
+    int c;
+
+    for (c = 0; c < xf86_config->num_crtc; c++) {
+        xf86CrtcPtr iter = xf86_config->crtc[c];
+        drmmode_crtc_private_ptr drmmode_crtc = iter->driver_private;
+        if (drmmode_crtc->plane_id == plane_id)
+            return TRUE;
+    }
+
+    return FALSE;
+}
+
+static void
+drmmode_crtc_create_planes(xf86CrtcPtr crtc, int num)
+{
+    drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
+    drmmode_ptr drmmode = drmmode_crtc->drmmode;
+    drmModePlaneRes *kplane_res;
+    drmModePlane *kplane;
+    drmModeObjectProperties *props;
+    uint32_t i, type;
+    int current_crtc, best_plane = 0;
+
+    static drmmode_prop_enum_info_rec plane_type_enums[] = {
+        [DRMMODE_PLANE_TYPE_PRIMARY] = {
+            .name = "Primary",
+        },
+        [DRMMODE_PLANE_TYPE_OVERLAY] = {
+            .name = "Overlay",
+        },
+        [DRMMODE_PLANE_TYPE_CURSOR] = {
+            .name = "Cursor",
+        },
+    };
+    static const drmmode_prop_info_rec plane_props[] = {
+        [DRMMODE_PLANE_TYPE] = {
+            .name = "type",
+            .enum_values = plane_type_enums,
+            .num_enum_values = DRMMODE_PLANE_TYPE__COUNT,
+        },
+        [DRMMODE_PLANE_FB_ID] = { .name = "FB_ID", },
+        [DRMMODE_PLANE_CRTC_ID] = { .name = "CRTC_ID", },
+    };
+    drmmode_prop_info_rec tmp_props[DRMMODE_PLANE__COUNT];
+
+    if (!drmmode_prop_info_copy(tmp_props, plane_props, DRMMODE_PLANE__COUNT, 0)) {
+        xf86DrvMsg(drmmode->scrn->scrnIndex, X_ERROR,
+                   "failed to copy plane property info\n");
+        return;
+    }
+
+    kplane_res = drmModeGetPlaneResources(drmmode->fd);
+    if (!kplane_res) {
+        xf86DrvMsg(drmmode->scrn->scrnIndex, X_ERROR,
+                   "failed to get plane resources: %s\n", strerror(errno));
+        return;
+    }
+
+    for (i = 0; i < kplane_res->count_planes; i++) {
+        int plane_id;
+
+        kplane = drmModeGetPlane(drmmode->fd, kplane_res->planes[i]);
+        if (!kplane)
+            continue;
+
+        if (!(kplane->possible_crtcs & (1 << num)) ||
+            is_plane_assigned(drmmode->scrn, kplane->plane_id)) {
+            drmModeFreePlane(kplane);
+            continue;
+        }
+
+        plane_id = kplane->plane_id;
+        drmModeFreePlane(kplane);
+
+        props = drmModeObjectGetProperties(drmmode->fd, plane_id,
+                                           DRM_MODE_OBJECT_PLANE);
+        if (!props) {
+            xf86DrvMsg(drmmode->scrn->scrnIndex, X_ERROR,
+                    "couldn't get plane properties\n");
+            continue;
+        }
+
+        drmmode_prop_info_update(drmmode, tmp_props, DRMMODE_PLANE__COUNT, props);
+
+        /* Only primary planes are important for atomic page-flipping */
+        type = drmmode_prop_get_value(&tmp_props[DRMMODE_PLANE_TYPE],
+                                      props, DRMMODE_PLANE_TYPE__COUNT);
+        if (type != DRMMODE_PLANE_TYPE_PRIMARY) {
+            drmModeFreeObjectProperties(props);
+            continue;
+        }
+
+        /* Check if plane is already on this CRTC */
+        current_crtc = drmmode_prop_get_value(&tmp_props[DRMMODE_PLANE_CRTC_ID],
+                                              props, 0);
+        if (current_crtc == drmmode_crtc->mode_crtc->crtc_id) {
+            if (best_plane)
+                drmmode_prop_info_free(drmmode_crtc->props_plane, DRMMODE_PLANE__COUNT);
+            best_plane = plane_id;
+            drmmode_prop_info_copy(drmmode_crtc->props_plane, tmp_props,
+                                   DRMMODE_PLANE__COUNT, 1);
+            drmModeFreeObjectProperties(props);
+            break;
+        }
+
+        if (!best_plane) {
+            best_plane = plane_id;
+            drmmode_prop_info_copy(drmmode_crtc->props_plane, tmp_props,
+                                   DRMMODE_PLANE__COUNT, 1);
+        }
+
+        drmModeFreeObjectProperties(props);
+    }
+
+    drmmode_crtc->plane_id = best_plane;
+
+    drmmode_prop_info_free(tmp_props, DRMMODE_PLANE__COUNT);
+    drmModeFreePlaneResources(kplane_res);
+}
+#endif
+
 static unsigned int
 drmmode_crtc_init(ScrnInfoPtr pScrn, drmmode_ptr drmmode, drmModeResPtr mode_res, int num)
 {
@@ -1143,6 +1504,10 @@ drmmode_crtc_init(ScrnInfoPtr pScrn, drmmode_ptr drmmode, drmModeResPtr mode_res
     drmmode_crtc->vblank_pipe = drmmode_crtc_vblank_pipe(num);
     crtc->driver_private = drmmode_crtc;
 
+#ifdef GLAMOR_HAS_DRM_ATOMIC
+    drmmode_crtc_create_planes(crtc, num);
+#endif
+
     /* Hide any cursors which may be active from previous users */
     drmModeSetCursor(drmmode->fd, drmmode_crtc->mode_crtc->crtc_id, 0, 0, 0);
 
@@ -1421,7 +1786,8 @@ drmmode_property_ignore(drmModePropertyPtr prop)
     if (prop->flags & DRM_MODE_PROP_BLOB)
         return TRUE;
     /* ignore standard property */
-    if (!strcmp(prop->name, "EDID") || !strcmp(prop->name, "DPMS"))
+    if (!strcmp(prop->name, "EDID") || !strcmp(prop->name, "DPMS") ||
+        !strcmp(prop->name, "CRTC_ID"))
         return TRUE;
 
     return FALSE;
diff --git a/hw/xfree86/drivers/modesetting/drmmode_display.h b/hw/xfree86/drivers/modesetting/drmmode_display.h
index f774250ef..fadc381db 100644
--- a/hw/xfree86/drivers/modesetting/drmmode_display.h
+++ b/hw/xfree86/drivers/modesetting/drmmode_display.h
@@ -36,6 +36,20 @@
 
 struct gbm_device;
 
+enum drmmode_plane_property {
+    DRMMODE_PLANE_TYPE = 0,
+    DRMMODE_PLANE_FB_ID,
+    DRMMODE_PLANE_CRTC_ID,
+    DRMMODE_PLANE__COUNT
+};
+
+enum drmmode_plane_type {
+    DRMMODE_PLANE_TYPE_PRIMARY = 0,
+    DRMMODE_PLANE_TYPE_CURSOR,
+    DRMMODE_PLANE_TYPE_OVERLAY,
+    DRMMODE_PLANE_TYPE__COUNT
+};
+
 typedef struct {
     struct dumb_bo *dumb;
 #ifdef GLAMOR_HAS_GBM
@@ -86,6 +100,19 @@ typedef struct {
 } drmmode_rec, *drmmode_ptr;
 
 typedef struct {
+    const char *name;
+    Bool valid;
+    uint64_t value;
+} drmmode_prop_enum_info_rec, *drmmode_prop_enum_info_ptr;
+
+typedef struct {
+    const char *name;
+    uint32_t prop_id;
+    unsigned int num_enum_values;
+    drmmode_prop_enum_info_rec *enum_values;
+} drmmode_prop_info_rec, *drmmode_prop_info_ptr;
+
+typedef struct {
     drmmode_ptr drmmode;
     drmModeCrtcPtr mode_crtc;
     uint32_t vblank_pipe;
@@ -94,6 +121,9 @@ typedef struct {
     Bool cursor_up;
     uint16_t lut_r[256], lut_g[256], lut_b[256];
 
+    drmmode_prop_info_rec props_plane[DRMMODE_PLANE__COUNT];
+    uint32_t plane_id;
+
     drmmode_bo rotate_bo;
     unsigned rotate_fb_id;
 
@@ -196,6 +226,10 @@ void drmmode_get_default_bpp(ScrnInfoPtr pScrn, drmmode_ptr drmmmode,
                              int *depth, int *bpp);
 
 void drmmode_copy_fb(ScrnInfoPtr pScrn, drmmode_ptr drmmode);
+
+int drmmode_crtc_set_fb(xf86CrtcPtr crtc, uint32_t fb_id,
+                        int x, int y, uint32_t flags, void *data);
+
 #ifndef DRM_CAP_DUMB_PREFERRED_DEPTH
 #define DRM_CAP_DUMB_PREFERRED_DEPTH 3
 #endif
diff --git a/hw/xfree86/drivers/modesetting/pageflip.c b/hw/xfree86/drivers/modesetting/pageflip.c
index d5fd0625b..dd296cd12 100644
--- a/hw/xfree86/drivers/modesetting/pageflip.c
+++ b/hw/xfree86/drivers/modesetting/pageflip.c
@@ -160,6 +160,25 @@ ms_pageflip_abort(void *data)
 }
 
 static Bool
+do_queue_flip_on_crtc(modesettingPtr ms, xf86CrtcPtr crtc,
+                      uint32_t flags, uint32_t seq)
+{
+    drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
+
+#ifdef GLAMOR_HAS_DRM_ATOMIC
+    if (ms->atomic_modeset) {
+        flags |= DRM_MODE_ATOMIC_NONBLOCK;
+        return drmmode_crtc_set_fb(crtc, ms->drmmode.fb_id, 0, 0, flags,
+                                   (void *) (uintptr_t) seq);
+    }
+#endif
+
+    return drmModePageFlip(ms->fd, drmmode_crtc->mode_crtc->crtc_id,
+                           ms->drmmode.fb_id, flags,
+                           (void *) (uintptr_t) seq);
+}
+
+static Bool
 queue_flip_on_crtc(ScreenPtr screen, xf86CrtcPtr crtc,
                    struct ms_flipdata *flipdata,
                    int ref_crtc_vblank_pipe, uint32_t flags)
@@ -193,8 +212,7 @@ queue_flip_on_crtc(ScreenPtr screen, xf86CrtcPtr crtc,
     /* take a reference on flipdata for use in flip */
     flipdata->flip_count++;
 
-    while (drmModePageFlip(ms->fd, drmmode_crtc->mode_crtc->crtc_id,
-                           ms->drmmode.fb_id, flags, (void *) (uintptr_t) seq)) {
+    while (do_queue_flip_on_crtc(ms, crtc, flags, seq)) {
         err = errno;
         /* We may have failed because the event queue was full.  Flush it
          * and retry.  If there was nothing to flush, then we failed for
diff --git a/include/dix-config.h.in b/include/dix-config.h.in
index 8e9dcdfcc..64102621e 100644
--- a/include/dix-config.h.in
+++ b/include/dix-config.h.in
@@ -503,6 +503,9 @@
 /* Build glamor use new drmGetDeviceNameFromFD2 */
 #undef GLAMOR_HAS_DRM_NAME_FROM_FD_2
 
+/* Glamor should use atomic DRM API */
+#undef GLAMOR_HAS_DRM_ATOMIC
+
 /* Glamor can use eglQueryDmaBuf* functions */
 #undef GLAMOR_HAS_EGL_QUERY_DMABUF