[devel-review_virtual_for_VT7205]

- Offset restricts the virtual resolution too.
- VT7205 does have bits 24 and 25 of Primary StartAddress.
- H values are all in 8 pixels. Why do VIA monkeys think it is 16?

1 files changed, 25 insertions, 20 deletions

diff --git a/src/via_driver.c b/src/via_driver.c
index 7aeaca0..68f384f 100644
--- a/src/via_driver.c
+++ b/src/via_driver.c
@@ -735,6 +735,7 @@ static Bool VIAPreInit(ScrnInfoPtr pScrn, int flags)
 #endif
     vgaHWPtr        hwp;
     int             i;
+    int  MaxHVirtual, MaxVVirtual;
 
     VIAFUNC(pScrn->scrnIndex);
 
@@ -1275,26 +1276,31 @@ static Bool VIAPreInit(ScrnInfoPtr pScrn, int flags)
     clockRanges->interlaceAllowed = TRUE;
     clockRanges->doubleScanAllowed = FALSE;
     
-    /*
-     * xf86ValidateModes will check that the mode HTotal and VTotal values
-     * don't exceed the chipset's limit if pScrn->maxHValue and
-     * pScrn->maxVValue are set.  Since our VIAValidMode() already takes
-     * care of this, we don't worry about setting them here.
+    /* Virtual mode limitations:
+     * 1) Offset: or FB line stride.
+     *    Primary: max 16kB - 8 (32bit: 4088 pixels per line)
+     *    Secondary: max 8kB - 8 (32bit: 2040 pixels per line)
      *
-     * VT3122A:
-     *   Max Line Pitch: 4080, (FB corruption when higher, driver problem?)
-     *   Max Height: 4096 (and beyond)
+     * 2) StartAddress:
+     *    Primary: Here we run into separate limits.
+     *      VT3122A: 32MB - 2 or roughly 2048 lines.
+     *      VT7205A: 128MB - 2 or twice the FB size :), so use 4096.
+     *    Secondary: 128MB - 8, but this needs verification.
      *
-     * VT3122A: primary AdjustFrame only is able to use 24bits, so we are
-     * limited to 12x11bits; 4080x2048 (~2:1), 3344x2508 (4:3) or 2896x2896
-     * (1:1). 
-     * Test VT3122Cx, VT7205, VT7205A, VT3108, VT3118, VT3344, VT3157 please.
+     * xf86ValidateModes forces you to hand it pixel counts for both H and V.
+     * Max pitch and Max startAddress would've been far more effective and
+     * far more dynamic.
      *
      * We should be able to limit the memory available for a mode to 32MB,
      * yet xf86ValidateModes (or miScanLineWidth) fails to catch this properly
      * (apertureSize).
      */
-    
+    MaxHVirtual = 4096 - 8;
+    if (pVia->Chipset == VT3122)
+        MaxVVirtual = 2048;
+    else
+        MaxVVirtual = 4096;
+
     /* Select valid modes from those available */
     i = xf86ValidateModes(pScrn,
                           pScrn->monitor->Modes,    /* availModes */
@@ -1302,10 +1308,10 @@ static Bool VIAPreInit(ScrnInfoPtr pScrn, int flags)
                           clockRanges,              /* list of clock ranges */
                           NULL,                     /* list of line pitches */
                           256,                      /* mini line pitch */
-                          3344,                     /* max line pitch */
-                          16 * pScrn->bitsPerPixel, /* pitch inc (bits) */
+                          MaxHVirtual,              /* max line pitch */
+                          8 * pScrn->bitsPerPixel,  /* pitch inc (bits) */
                           128,                      /* min height */
-                          2508,                     /* max height */
+                          MaxVVirtual,              /* max height */
                           pScrn->display->virtualX, /* virtual width */
                           pScrn->display->virtualY, /* virtual height */
                           pVia->videoRambytes,      /* apertureSize */
@@ -1976,7 +1982,7 @@ VIAScreenInit(int scrnIndex, ScreenPtr pScreen, int argc, char **argv)
 
     if (pVia->hwcursor && !ViaCursorInit(pScrn, pScreen))
         xf86DrvMsg(pScrn->scrnIndex, X_ERROR,
-                       "Hardware cursor initialization failed\n");
+                   "Hardware cursor initialization failed\n");
 
     if (pVia->shadowFB)
 	ViaShadowFBInit(pScrn, pScreen);
@@ -2227,10 +2233,9 @@ VIAAdjustFrame(int scrnIndex, int x, int y, int flags)
         hwp->writeCrtc(hwp, 0x0C, (Base & 0xFF00) >> 8);
 	hwp->writeCrtc(hwp, 0x0D, Base & 0xFF);
 	hwp->writeCrtc(hwp, 0x34, (Base & 0xFF0000) >> 16);
-#if 0
-	/* The VT3122A doesn't have this implemented, it seems. -- Luc */
+	/* VT3122A doesn't implement this, but luckily it simply doesn't care.
+         * Value is properly limited in PreInit anyway. */
 	ViaCrtcMask(hwp, 0x48, Base >> 24, 0x03);
-#endif
     }
 }