Re: [PATCH v5 0/7] drm/mgag200: Implement VBLANK support

Thomas Zimmermann <tzimmermann@xxxxxxx> · Fri, 4 Oct 2024 11:17:02 +0200

Hi

Am 02.10.24 um 18:15 schrieb Luck, Tony:
Thanks for the bug report. Can you provide the output of 'sudo lspci
-vvv' for the graphics device?
Thomas,

Sure. Here's the output (run on the v6.11.0 kernel)

Thanks. It doesn't look much different from other systems. IRQ is also 
assigned.

Attached is a patch that fixes a possible off-by-one error in the 
register settings. This would affect the bug you're reporting. If 
possible, please apply the patch to your 6.12-rc1, test and report the 
result.

Best regards
Thomas


$ sudo lspci -vvv -s 0000:08:00.0
08:00.0 VGA compatible controller: Matrox Electronics Systems Ltd. MGA G200e [Pilot] ServerEngines (SEP1) (rev 05) (prog-if 00 [VGA controller])
         Subsystem: Intel Corporation Device 0103
         Control: I/O+ Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
         Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
         Interrupt: pin A routed to IRQ 16
         Region 0: Memory at 90000000 (32-bit, prefetchable) [size=16M]
         Region 1: Memory at 91800000 (32-bit, non-prefetchable) [size=16K]
         Region 2: Memory at 91000000 (32-bit, non-prefetchable) [size=8M]
         Expansion ROM at 91810000 [disabled] [size=64K]
         Capabilities: [dc] Power Management version 2
                 Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                 Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
         Capabilities: [e4] Express (v1) Legacy Endpoint, MSI 00
                 DevCap: MaxPayload 256 bytes, PhantFunc 0, Latency L0s <64ns, L1 <1us
                         ExtTag- AttnBtn- AttnInd- PwrInd- RBE- FLReset-
                 DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq-
                         RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
                         MaxPayload 128 bytes, MaxReadReq 128 bytes
                 DevSta: CorrErr+ NonFatalErr- FatalErr- UnsupReq+ AuxPwr- TransPend-
                 LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s, Exit Latency L0s <64ns
                         ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
                 LnkCtl: ASPM Disabled; RCB 64 bytes, Disabled- CommClk+
                         ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
                 LnkSta: Speed 2.5GT/s (ok), Width x1 (ok)
                         TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
         Capabilities: [54] MSI: Enable- Count=1/1 Maskable- 64bit-
                 Address: 00000000  Data: 0000
         Kernel driver in use: mgag200
         Kernel modules: mgag200

-Tony

--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)
From 30052c410ba5de710506c7279b6434db39e60906 Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann@xxxxxxx>
Date: Fri, 4 Oct 2024 10:43:04 +0200
Subject: [PATCH] drm/matrox: Fix off-by-one error in vblank start value

---
 drivers/gpu/drm/mgag200/mgag200_mode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index 7159909aca1e..9d905b379f38 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -224,7 +224,7 @@ void mgag200_set_mode_regs(struct mga_device *mdev, const struct drm_display_mod
 	vsyncstr = mode->crtc_vsync_start - 1;
 	vsyncend = mode->crtc_vsync_end - 1;
 	vtotal = mode->crtc_vtotal - 2;
-	vblkstr = mode->crtc_vblank_start;
+	vblkstr = mode->crtc_vblank_start - 1;
 	vblkend = vtotal + 1;
 
 	/*
-- 
2.46.0





