From 287a960c316ecae5cb87c9d23dcb25810d67a0d1 Mon Sep 17 00:00:00 2001

From: Kishore Kadiyala <kishore.kadiyala@intel.com>

Date: Sat, 19 Sep 2020 01:28:14 +0530

Subject: [PATCH xserver 2/2] modesetting: keep going if a modeset fails on

 EnterVT

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There was a time when setting a mode on a CRTC would not depend on the

associated connector's state. If a mode had been set successfully once,

it would mean it would work later on.

This changed with the introduction of new connectors type that now

require a link training sequence (DP, HDMI 2.0), and that means that

some events may have happened while the X server was not master that

would then prevent the mode from successfully be restored to its

previous state.

This patch relaxes the requirement that all modes should be restored on

EnterVT, or the entire X-Server would go down by allowing modesets to

fail (with some warnings). If a modeset fails, the CRTC will be

disabled, and a RandR event will be sent for the desktop environment to

fix the situation as well as possible.

Additional patches might be needed to make sure that the user would

never be left with all screens black in some scenarios.

v2 (Martin Peres):

 - whitespace fixes

 - remove the uevent handling (it is done in a previous patch)

 - improve the commit message

 - reduce the size of the patch by not changing lines needlessly

 - return FALSE if one modeset fails in ignore mode

 - add comments/todos to explain why we do things

 - disable the CRTCs that failed the modeset

Signed-off-by: Kishore Kadiyala <kishore.kadiyala@intel.com>

Signed-off-by: Martin Peres <martin.peres@linux.intel.com>

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Tested-by: Kishore Kadiyala <kishore.kadiyala@intel.com>

Closes: #1010

Signed-off-by: Michel Dänzer <mdaenzer@redhat.com>

---

 hw/xfree86/drivers/modesetting/driver.c       | 23 +++++++++++++++----

 .../drivers/modesetting/drmmode_display.c     | 19 +++++++++++----

 .../drivers/modesetting/drmmode_display.h     |  3 ++-

 3 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/hw/xfree86/drivers/modesetting/driver.c b/hw/xfree86/drivers/modesetting/driver.c

index a4d486a67..ef4a3147d 100644

--- a/hw/xfree86/drivers/modesetting/driver.c

+++ b/hw/xfree86/drivers/modesetting/driver.c

@@ -705,7 +705,7 @@ msBlockHandler_oneshot(ScreenPtr pScreen, void *pTimeout)

     msBlockHandler(pScreen, pTimeout);

-    drmmode_set_desired_modes(pScrn, &ms->drmmode, TRUE);

+    drmmode_set_desired_modes(pScrn, &ms->drmmode, TRUE, FALSE);

 }

 static void

@@ -1348,7 +1348,7 @@ CreateScreenResources(ScreenPtr pScreen)

     ret = pScreen->CreateScreenResources(pScreen);

     pScreen->CreateScreenResources = CreateScreenResources;

-    if (!drmmode_set_desired_modes(pScrn, &ms->drmmode, pScrn->is_gpu))

+    if (!drmmode_set_desired_modes(pScrn, &ms->drmmode, pScrn->is_gpu, FALSE))

         return FALSE;

     if (!drmmode_glamor_handle_new_screen_pixmap(&ms->drmmode))

@@ -1822,8 +1822,23 @@ EnterVT(ScrnInfoPtr pScrn)

     drmmode_update_kms_state(&ms->drmmode);

-    if (!drmmode_set_desired_modes(pScrn, &ms->drmmode, TRUE))

-        return FALSE;

+    /* allow not all modes to be set successfully since some events might have

+     * happened while not being master that could prevent the previous

+     * configuration from being re-applied.

+     */

+    if (!drmmode_set_desired_modes(pScrn, &ms->drmmode, TRUE, TRUE)) {

+        xf86DisableUnusedFunctions(pScrn);

+

+        /* TODO: check that at least one screen is on, to allow the user to fix

+         * their setup if all modeset failed...

+         */

+

+        /* Tell the desktop environment that something changed, so that they

+         * can hopefully correct the situation

+         */

+        RRSetChanged(xf86ScrnToScreen(pScrn));

+        RRTellChanged(xf86ScrnToScreen(pScrn));

+    }

     return TRUE;

 }

diff --git a/hw/xfree86/drivers/modesetting/drmmode_display.c b/hw/xfree86/drivers/modesetting/drmmode_display.c

index 646bacecb..88992f521 100644

--- a/hw/xfree86/drivers/modesetting/drmmode_display.c

+++ b/hw/xfree86/drivers/modesetting/drmmode_display.c

@@ -3457,9 +3457,11 @@ drmmode_adjust_frame(ScrnInfoPtr pScrn, drmmode_ptr drmmode, int x, int y)

 }

 Bool

-drmmode_set_desired_modes(ScrnInfoPtr pScrn, drmmode_ptr drmmode, Bool set_hw)

+drmmode_set_desired_modes(ScrnInfoPtr pScrn, drmmode_ptr drmmode, Bool set_hw,

+                          Bool ign_err)

 {

     xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(pScrn);

+    Bool success = TRUE;

     int c;

     for (c = 0; c < config->num_crtc; c++) {

@@ -3507,8 +3509,17 @@ drmmode_set_desired_modes(ScrnInfoPtr pScrn, drmmode_ptr drmmode, Bool set_hw)

         if (set_hw) {

             if (!crtc->funcs->

                 set_mode_major(crtc, &crtc->desiredMode, crtc->desiredRotation,

-                               crtc->desiredX, crtc->desiredY))

-                return FALSE;

+                               crtc->desiredX, crtc->desiredY)) {

+                if (!ign_err)

+                    return FALSE;

+                else {

+                    success = FALSE;

+                    crtc->enabled = FALSE;

+                    xf86DrvMsg(pScrn->scrnIndex, X_WARNING,

+                               "Failed to set the desired mode on connector %s\n",

+                               output->name);

+                }

+            }

         } else {

             crtc->mode = crtc->desiredMode;

             crtc->rotation = crtc->desiredRotation;

@@ -3522,7 +3533,7 @@ drmmode_set_desired_modes(ScrnInfoPtr pScrn, drmmode_ptr drmmode, Bool set_hw)

     /* Validate leases on VT re-entry */

     drmmode_validate_leases(pScrn);

-    return TRUE;

+    return success;

 }

 static void

diff --git a/hw/xfree86/drivers/modesetting/drmmode_display.h b/hw/xfree86/drivers/modesetting/drmmode_display.h

index 6ef8ab9e4..59d79e9a0 100644

--- a/hw/xfree86/drivers/modesetting/drmmode_display.h

+++ b/hw/xfree86/drivers/modesetting/drmmode_display.h

@@ -278,7 +278,8 @@ void drmmode_DisableSharedPixmapFlipping(xf86CrtcPtr crtc, drmmode_ptr drmmode);

 extern Bool drmmode_pre_init(ScrnInfoPtr pScrn, drmmode_ptr drmmode, int cpp);

 extern Bool drmmode_init(ScrnInfoPtr pScrn, drmmode_ptr drmmode);

 void drmmode_adjust_frame(ScrnInfoPtr pScrn, drmmode_ptr drmmode, int x, int y);

-extern Bool drmmode_set_desired_modes(ScrnInfoPtr pScrn, drmmode_ptr drmmode, Bool set_hw);

+extern Bool drmmode_set_desired_modes(ScrnInfoPtr pScrn, drmmode_ptr drmmode,

+                                      Bool set_hw, Bool ign_err);

 extern Bool drmmode_setup_colormap(ScreenPtr pScreen, ScrnInfoPtr pScrn);

 extern void drmmode_update_kms_state(drmmode_ptr drmmode);

-- 

2.28.0