On Mon, Feb 20, 2017 at 04:37:47PM +0100, Tomasz Lis wrote:
> I tested this variant (reverted the change to "pass" variable before
> testing), and it fixes the issue with count=0 as well as possible
> infinite loop issue.
>
> But something needs to be done with the "pass" var, one way or the
> other - commented below.
>
>
> W dniu 2017-02-18 o 16:37, Chris Wilson pisze:
> >If we cease making progress in finding matching outputs for a tiled
> >configuration, stop looping over the remaining unconfigured outputs.
> >
> >Fixes: b0ee9e7fa5b4 ("drm/fb: add support for tiled monitor configurations. (v2)")
> >Cc: Tomasz Lis <tomasz.lis@xxxxxxxxx>
> >Cc: Dave Airlie <airlied@xxxxxxxxxx>
> >Cc: Daniel Vetter <daniel.vetter@xxxxxxxxx>
> >Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
> >Cc: Sean Paul <seanpaul@xxxxxxxxxxxx>
> >Cc: <stable@xxxxxxxxxxxxxxx> # v3.19+
> >---
> > drivers/gpu/drm/i915/intel_fbdev.c | 7 +++----
> > 1 file changed, 3 insertions(+), 4 deletions(-)
> >
> >diff --git a/drivers/gpu/drm/i915/intel_fbdev.c b/drivers/gpu/drm/i915/intel_fbdev.c
> >index 041322fef607..32d0af6b07a7 100644
> >--- a/drivers/gpu/drm/i915/intel_fbdev.c
> >+++ b/drivers/gpu/drm/i915/intel_fbdev.c
> >@@ -348,7 +348,7 @@ static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
> > bool *enabled, int width, int height)
> > {
> > struct drm_i915_private *dev_priv = to_i915(fb_helper->dev);
> >- unsigned long conn_configured, mask;
> >+ unsigned long conn_configured, conn_seq, mask;
> > unsigned int count = min(fb_helper->connector_count, BITS_PER_LONG);
> > int i, j;
> > bool *save_enabled;
> >@@ -365,6 +365,7 @@ static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
> > mask = 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;
> >@@ -489,10 +490,8 @@ static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
> > conn_configured |= BIT(i);
> > }
> >- if ((conn_configured & mask) != mask) {
> >- pass++;
> This doesn't seem right; increasing the amount of passes should
> stay, or the use of "pass" variable should be completely replaced by
> conn_seq.
Good catch.
diff --git a/drivers/gpu/drm/i915/intel_fbdev.c b/drivers/gpu/drm/i915/intel_fbdev.c
index 32d0af6b07a7..f7e9a4e69595 100644
--- a/drivers/gpu/drm/i915/intel_fbdev.c
+++ b/drivers/gpu/drm/i915/intel_fbdev.c
@@ -355,7 +355,6 @@ static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
bool fallback = true;
int num_connectors_enabled = 0;
int num_connectors_detected = 0;
- int pass = 0;
save_enabled = kcalloc(count, sizeof(bool), GFP_KERNEL);
if (!save_enabled)
@@ -379,7 +378,7 @@ static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
if (conn_configured & BIT(i))
continue;
- if (pass == 0 && !connector->has_tile)
+ if (conn_seq == 0 && !connector->has_tile)
continue;
if (connector->status == connector_status_connected)
Suggestions for a better name than conn_seq much appreciated.
-Chris
--
Chris Wilson, Intel Open Source Technology Centre