From: Zhenyu Wang <zhenyu.z.wang@intel.com>
Date: Thu, 11 Sep 2008 07:49:41 +0000 (+0800)
Subject: Disable render standby
X-Git-Tag: xf86-4_3_0_1
X-Git-Url: http://gitweb.freedesktop.org/?p=xorg/driver/xf86-video-intel.git;a=commitdiff;h=86f82c429f5d7067c52d3b783988917869e13d1d

Disable render standby

Render standby is known to cause possible hang issue on some
mobile chips, so always disable it.
---

--- a/src/i810_reg.h
+++ b/src/i810_reg.h
@@ -2815,4 +2815,7 @@ typedef enum {
 
 #define PEG_BAND_GAP_DATA	0x14d68
 
+#define MCHBAR_RENDER_STANDBY	0x111B8
+#define RENDER_STANDBY_ENABLE	(1 << 30)
+
 #endif /* _I810_REG_H */
--- a/src/i830_driver.c
+++ b/src/i830_driver.c
@@ -2718,6 +2718,23 @@ i830_memory_init(ScrnInfoPtr pScrn)
     return FALSE;
 }
 
+static void
+i830_disable_render_standby(ScrnInfoPtr pScrn)
+{
+   I830Ptr pI830 = I830PTR(pScrn);
+   uint32_t render_standby;
+
+   /* Render Standby might cause hang issue, try always disable it.*/
+   if (IS_I965GM(pI830) || IS_GM45(pI830)) {
+       render_standby = INREG(MCHBAR_RENDER_STANDBY);
+       if (render_standby & RENDER_STANDBY_ENABLE) {
+	   xf86DrvMsg(pScrn->scrnIndex, X_INFO, "Disable render standby.\n");
+	   OUTREG(MCHBAR_RENDER_STANDBY,
+		   (render_standby & (~RENDER_STANDBY_ENABLE)));
+       }
+   }
+}
+
 static Bool
 I830ScreenInit(int scrnIndex, ScreenPtr pScreen, int argc, char **argv)
 {
@@ -3053,6 +3070,8 @@ I830ScreenInit(int scrnIndex, ScreenPtr 
    if (!vgaHWMapMem(pScrn))
       return FALSE;
 
+   i830_disable_render_standby(pScrn);
+
    DPRINTF(PFX, "assert( if(!I830EnterVT(scrnIndex, 0)) )\n");
 
    if (!pI830->useEXA) {