From aeb4bf93d4a09f6658b382da598eae5ba0cfb899 Mon Sep 17 00:00:00 2001
From: Rudolf Cornelissen <rudolf.cornelissen@gmail.com>
Date: Tue, 26 May 2009 18:34:05 +0000
Subject: [PATCH] git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30867
 a95241bf-73f2-0310-859d-f6bbb57e9c96

---
 .../accelerants/nvidia/engine/nv_acc_dma.c    | 20 ++++++++++++++-----
 .../accelerants/nvidia/engine/nv_general.c    |  2 +-
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/src/add-ons/accelerants/nvidia/engine/nv_acc_dma.c b/src/add-ons/accelerants/nvidia/engine/nv_acc_dma.c
index 6a6ec90b13..95cf333460 100644
--- a/src/add-ons/accelerants/nvidia/engine/nv_acc_dma.c
+++ b/src/add-ons/accelerants/nvidia/engine/nv_acc_dma.c
@@ -106,11 +106,21 @@ status_t nv_acc_init_dma()
 	}
 
 	/* setup PTIMER: */
-	//fixme? how about NV28 setup as just after coldstarting? (see nv_info.c)
-	/* set timer numerator to 8 (in b0-15) */
-	ACCW(PT_NUMERATOR, 0x00000008);
-	/* set timer denominator to 3 (in b0-15) */
-	ACCW(PT_DENOMINATR, 0x00000003);
+	LOG(4,("ACC_DMA: timer numerator $%08x, denominator $%08x\n", ACCR(PT_NUMERATOR), ACCR(PT_DENOMINATR)));
+
+	/* The NV28 BIOS programs PTIMER like this (see coldstarting in nv_info.c) */
+	//ACCW(PT_NUMERATOR, (si->ps.std_engine_clock * 20));
+	//ACCW(PT_DENOMINATR, 0x00000271);
+	/* Nouveau (march 2009) mentions something like: writing 8 and 3 to these regs breaks the timings
+	 * on the LVDS hardware sequencing microcode. A correct solution involves calculations with the GPU PLL. */
+
+	/* For now use BIOS pre-programmed values if there */
+	if (!ACCR(PT_NUMERATOR) || !ACCR(PT_DENOMINATR)) {
+		/* set timer numerator to 8 (in b0-15) */
+		ACCW(PT_NUMERATOR, 0x00000008);
+		/* set timer denominator to 3 (in b0-15) */
+		ACCW(PT_DENOMINATR, 0x00000003);
+	}
 
 	/* disable timer-alarm INT requests (b0) */
 	ACCW(PT_INTEN, 0x00000000);
diff --git a/src/add-ons/accelerants/nvidia/engine/nv_general.c b/src/add-ons/accelerants/nvidia/engine/nv_general.c
index 88fd7d9e13..e62ae985ea 100644
--- a/src/add-ons/accelerants/nvidia/engine/nv_general.c
+++ b/src/add-ons/accelerants/nvidia/engine/nv_general.c
@@ -92,7 +92,7 @@ status_t nv_general_powerup()
 {
 	status_t status;
 
-	LOG(1,("POWERUP: Haiku nVidia Accelerant 0.90 running.\n"));
+	LOG(1,("POWERUP: Haiku nVidia Accelerant 0.91 running.\n"));
 
 	/* log VBLANK INT usability status */
 	if (si->ps.int_assigned)