4.20-stable review patch. If anyone has any objections, please let me know.
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From: Chris Wilson chris@chris-wilson.co.uk
commit d179b88deb3bf6fed4991a31fd6f0f2cad21fab5 upstream.
If we skipped all the connectors that were not part of a tile, we would leave conn_seq=0 and conn_configured=0, convincing ourselves that we had stagnated in our configuration attempts. Avoid this situation by starting conn_seq=ALL_CONNECTORS, and repeating until we find no more connectors to configure.
Fixes: 754a76591b12 ("drm/i915/fbdev: Stop repeating tile configuration on stagnation") Reported-by: Maarten Lankhorst maarten.lankhorst@linux.intel.com Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Reviewed-by: Maarten Lankhorst maarten.lankhorst@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20190215123019.32283-1-chris@c... Cc: stable@vger.kernel.org # v3.19+ (cherry picked from commit d9b308b1f8a1acc0c3279f443d4fe0f9f663252e) Signed-off-by: Jani Nikula jani.nikula@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpu/drm/i915/intel_fbdev.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)
--- a/drivers/gpu/drm/i915/intel_fbdev.c +++ b/drivers/gpu/drm/i915/intel_fbdev.c @@ -336,8 +336,8 @@ static bool intel_fb_initial_config(stru bool *enabled, int width, int height) { struct drm_i915_private *dev_priv = to_i915(fb_helper->dev); - unsigned long conn_configured, conn_seq, mask; unsigned int count = min(fb_helper->connector_count, BITS_PER_LONG); + unsigned long conn_configured, conn_seq; int i, j; bool *save_enabled; bool fallback = true, ret = true; @@ -355,10 +355,9 @@ static bool intel_fb_initial_config(stru drm_modeset_backoff(&ctx);
memcpy(save_enabled, enabled, count); - mask = GENMASK(count - 1, 0); + conn_seq = GENMASK(count - 1, 0); conn_configured = 0; retry: - conn_seq = conn_configured; for (i = 0; i < count; i++) { struct drm_fb_helper_connector *fb_conn; struct drm_connector *connector; @@ -371,7 +370,8 @@ retry: if (conn_configured & BIT(i)) continue;
- if (conn_seq == 0 && !connector->has_tile) + /* First pass, only consider tiled connectors */ + if (conn_seq == GENMASK(count - 1, 0) && !connector->has_tile) continue;
if (connector->status == connector_status_connected) @@ -475,8 +475,10 @@ retry: conn_configured |= BIT(i); }
- if ((conn_configured & mask) != mask && conn_configured != conn_seq) + if (conn_configured != conn_seq) { /* repeat until no more are found */ + conn_seq = conn_configured; goto retry; + }
/* * If the BIOS didn't enable everything it could, fall back to have the