Add ForceLowPowerMode Option

Force the chip to a low power mode at the expense
of performance.

4 files changed, 47 insertions, 1 deletions

diff --git a/man/radeon.man b/man/radeon.man
index 9a7cf807..f6167038 100644
--- a/man/radeon.man
+++ b/man/radeon.man
@@ -419,6 +419,11 @@ life by reducing power usage.  Some users report reduced 3D performance
 with this enabled.  The default is
 .B off.
 .TP
+.BI "Option \*qForceLowPowerMode\*q \*q" boolean \*q
+Enable a static low power mode.  This can help reduce heat and increase battery
+life by reducing power usage at the expense of performance. The default is
+.B off.
+.TP
 .BI "Option \*qVGAAccess\*q \*q" boolean \*q
 Tell the driver if it can do legacy VGA IOs to the card. This is
 necessary for properly resuming consoles when in VGA text mode, but
diff --git a/src/radeon.h b/src/radeon.h
index 60d56db2..88de0e8f 100644
--- a/src/radeon.h
+++ b/src/radeon.h
@@ -207,7 +207,8 @@ typedef enum {
     OPTION_INT10,
     OPTION_EXA_VSYNC,
     OPTION_ATOM_TVOUT,
-    OPTION_R4XX_ATOM
+    OPTION_R4XX_ATOM,
+    OPTION_FORCE_LOW_POWER
 } RADEONOpts;
 
 
@@ -891,6 +892,9 @@ typedef struct {
 
     Bool              r4xx_atom;
 
+    /* pm */
+    Bool              low_power_mode;
+
 } RADEONInfoRec, *RADEONInfoPtr;
 
 #define RADEONWaitForFifo(pScrn, entries)				\
@@ -1070,6 +1074,7 @@ extern void RADEONRestoreMemMapRegisters(ScrnInfoPtr pScrn,
 
 /* radeon_pm.c */
 extern void RADEONSetClockGating(ScrnInfoPtr pScrn, Bool enable);
+extern void RADEONStaticLowPowerMode(ScrnInfoPtr pScrn, Bool enable);
 
 #ifdef USE_EXA
 /* radeon_exa.c */
diff --git a/src/radeon_driver.c b/src/radeon_driver.c
index fe00dd79..ac1a151e 100644
--- a/src/radeon_driver.c
+++ b/src/radeon_driver.c
@@ -195,6 +195,7 @@ static const OptionInfoRec RADEONOptions[] = {
     { OPTION_EXA_VSYNC,         "EXAVSync",        OPTV_BOOLEAN, {0}, FALSE },
     { OPTION_ATOM_TVOUT,	"ATOMTVOut",	   OPTV_BOOLEAN, {0}, FALSE },
     { OPTION_R4XX_ATOM,	        "R4xxATOM",	   OPTV_BOOLEAN, {0}, FALSE },
+    { OPTION_FORCE_LOW_POWER,	"ForceLowPowerMode", OPTV_BOOLEAN, {0}, FALSE },
     { -1,                    NULL,               OPTV_NONE,    {0}, FALSE }
 };
 
@@ -3333,6 +3334,9 @@ Bool RADEONScreenInit(int scrnIndex, ScreenPtr pScreen,
     else
 	RADEONSetClockGating(pScrn, FALSE);
 
+    if (xf86ReturnOptValBool(info->Options, OPTION_FORCE_LOW_POWER, FALSE))
+	RADEONStaticLowPowerMode(pScrn, TRUE);
+
     if (info->allowColorTiling && (pScrn->virtualX > info->MaxSurfaceWidth)) {
 	xf86DrvMsg(pScrn->scrnIndex, X_INFO,
 		   "Color tiling not supported with virtual x resolutions larger than %d, disabling\n",
@@ -5593,6 +5597,9 @@ Bool RADEONEnterVT(int scrnIndex, int flags)
     else
 	RADEONSetClockGating(pScrn, FALSE);
 
+    if (xf86ReturnOptValBool(info->Options, OPTION_FORCE_LOW_POWER, FALSE))
+	RADEONStaticLowPowerMode(pScrn, TRUE);
+
     for (i = 0; i < config->num_crtc; i++)
 	radeon_crtc_modeset_ioctl(config->crtc[i], TRUE);
 
@@ -5753,6 +5760,9 @@ static Bool RADEONCloseScreen(int scrnIndex, ScreenPtr pScreen)
     xf86DrvMsgVerb(pScrn->scrnIndex, X_INFO, RADEON_LOGLEVEL_DEBUG,
 		   "RADEONCloseScreen\n");
 
+    if (xf86ReturnOptValBool(info->Options, OPTION_FORCE_LOW_POWER, FALSE))
+	RADEONStaticLowPowerMode(pScrn, FALSE);
+
     /* Mark acceleration as stopped or we might try to access the engine at
      * wrong times, especially if we had DRI, after DRI has been stopped
      */
diff --git a/src/radeon_pm.c b/src/radeon_pm.c
index 89e1d8ab..86d739b2 100644
--- a/src/radeon_pm.c
+++ b/src/radeon_pm.c
@@ -476,3 +476,29 @@ RADEONSetClockGating(ScrnInfoPtr pScrn, Bool enable)
 	       enable ? "En" : "Dis");
 }
 
+void RADEONStaticLowPowerMode(ScrnInfoPtr pScrn, Bool enable)
+{
+    RADEONInfoPtr  info       = RADEONPTR(pScrn);
+    int sclk = (int)info->sclk * 100; /* 10 khz */
+
+    RADEONWaitForIdleMMIO(pScrn);
+
+    if (enable) {
+	if (info->IsAtomBios)
+	    atombios_set_engine_clock(pScrn, sclk/2);
+	else
+	    RADEONSetEngineClock(pScrn, sclk/2);
+
+	info->low_power_mode = TRUE;
+    } else {
+	if (info->IsAtomBios)
+	    atombios_set_engine_clock(pScrn, sclk);
+	else
+	    RADEONSetEngineClock(pScrn, sclk);
+
+	info->low_power_mode = FALSE;
+    }
+
+    xf86DrvMsg(pScrn->scrnIndex, X_INFO, "Low Power Mode %sabled\n",
+	       enable ? "En" : "Dis");
+}