Unless there is a xorg.conf option, don't modify mclck neither mxclck.

  The option set_mclck was renamed to just MCLK, and a new MXCLCK option
was added for smi501/502 chips.
  Note that previously, on MSOC chips, the set_mclck option actually
changed mxclck, what is now done by the MXCLK option.
  The manpage was also update to reflect the options usage.
  A new SMI501_FindMemClock() function was added, as a possible
placeholder for choosing alternate clocks when programming MMIO 0x68.
But it should be noted that the smi 501 databook says:
Miscellaneous Timing
	Read/Write MMIO_base + 0x000068
	Power-on Default 0x00000000
	[...]
	5:4 Divider Output Frequency Selection for Second PLL.
		00: 336 MHz.
		01: 288 MHz.
		10: 240 MHz.
		11: 192 MHz.
while the 502 databook says:
	Miscellaneous Timing
	Read/Write MMIO_base + 0x000068
	Power-on Default 0b0000.00xx.0000.1001.0000.1001.0000.0000
	[...]
	5:4 Reserved These bits are reserved.
but still tells to refer to those bits.

4 files changed, 98 insertions, 59 deletions

diff --git a/src/smi.h b/src/smi.h
index 05332f7..5305e54 100644
--- a/src/smi.h
+++ b/src/smi.h
@@ -144,6 +144,7 @@ typedef struct
 {
     int			Bpp;		/* Bytes per pixel */
     int			MCLK;		/* Memory Clock  */
+    int			MXCLK;		/* MSOC Clock for local sdram */
     ClockRanges		clockRange;	/* Allowed pixel clock range */
     CloseScreenProcPtr	CloseScreen;	/* Pointer used to save wrapped
 					   CloseScreen function */
diff --git a/src/smi_501.c b/src/smi_501.c
index 465b8f3..3aa81de 100644
--- a/src/smi_501.c
+++ b/src/smi_501.c
@@ -168,6 +168,7 @@ SMI501_HWInit(ScrnInfoPtr pScrn)
     MSOCRegPtr	save;
     MSOCRegPtr	mode;
     SMIPtr	pSmi = SMIPTR(pScrn);
+    int32_t	x_select, x_divider, x_shift;
 
     save = pSmi->save;
     mode = pSmi->mode;
@@ -194,38 +195,25 @@ SMI501_HWInit(ScrnInfoPtr pScrn)
     mode->power_ctl.f.status = 0;
     mode->power_ctl.f.mode = 0;
 
-    /* FIXME fixed at 336/3/0 as in the smi sources */
-    mode->clock.f.m_select = 1;
-    mode->clock.f.m_divider = 1;
-    mode->clock.f.m_shift = 0;
-
-    switch (pSmi->MCLK) {
-	case 168000:	    /* 336/1/1 */
-	    mode->clock.f.m1_select = 1;
-	    mode->clock.f.m1_divider = 0;
-	    mode->clock.f.m1_shift = 1;
-	    break;
-	case 96000:	    /* 288/3/0 */
-	    mode->clock.f.m1_select = 0;
-	    mode->clock.f.m1_divider = 1;
-	    mode->clock.f.m1_shift = 0;
-	    break;
-	case 144000:	    /* 288/1/1 */
-	    mode->clock.f.m1_select = 0;
-	    mode->clock.f.m1_divider = 0;
-	    mode->clock.f.m1_shift = 1;
-	    break;
-	case 112000:	    /* 336/3/0 */
-	    mode->clock.f.m1_select = 1;
-	    mode->clock.f.m1_divider = 1;
-	    mode->clock.f.m1_shift = 0;
-	    break;
-	default:
-	    /* Do nothing. Use what was configured by the kernel.
-	     * Accordingly to SMI, this should be 144Mhz for 6ns sdram,
-	     * or 112Mhz for other types of sdram. */
-	    break;
+    if (pSmi->MCLK) {
+	xf86DrvMsgVerb(pScrn->scrnIndex, X_INFO, VERBLEV,
+		       "MCLK request %d\n", pSmi->MCLK);
+	(void)SMI501_FindMemClock(pSmi->MCLK, &x_select, &x_divider, &x_shift);
+	mode->clock.f.m_select = x_select;
+	mode->clock.f.m_divider = x_divider;
+	mode->clock.f.m_shift = x_shift;
     }
+    /* Else use what was configured by the kernel. */
+
+    if (pSmi->MXCLK) {
+	xf86DrvMsgVerb(pScrn->scrnIndex, X_INFO, VERBLEV,
+		       "MXCLK request %d\n", pSmi->MXCLK);
+	(void)SMI501_FindMemClock(pSmi->MXCLK, &x_select, &x_divider, &x_shift);
+	mode->clock.f.m1_select = x_select;
+	mode->clock.f.m1_divider = x_divider;
+	mode->clock.f.m1_shift = x_shift;
+    }
+    /* Else use what was configured by the kernel. */
 
     if (!pSmi->Dualhead) {
 	/* crt clones panel */
@@ -253,17 +241,21 @@ SMI501_WriteMode_common(ScrnInfoPtr pScrn, MSOCRegPtr mode)
 
 	clock.value = READ_SCR(pSmi, mode->current_clock);
 
-	clock.f.m_select = mode->clock.f.m_select;
-	pll = clock.value;
-	clock.f.m_divider = mode->clock.f.m_divider;
-	clock.f.m_shift = mode->clock.f.m_shift;
-	SMI501_SetClock(pSmi, mode->current_clock, pll, clock.value);
+	if (pSmi->MCLK) {
+	    clock.f.m_select = mode->clock.f.m_select;
+	    pll = clock.value;
+	    clock.f.m_divider = mode->clock.f.m_divider;
+	    clock.f.m_shift = mode->clock.f.m_shift;
+	    SMI501_SetClock(pSmi, mode->current_clock, pll, clock.value);
+	}
 
-	clock.f.m1_select = mode->clock.f.m1_select;
-	pll = clock.value;
-	clock.f.m1_divider = mode->clock.f.m1_divider;
-	clock.f.m1_shift = mode->clock.f.m1_shift;
-	SMI501_SetClock(pSmi, mode->current_clock, pll, clock.value);
+	if (pSmi->MXCLK) {
+	    clock.f.m1_select = mode->clock.f.m1_select;
+	    pll = clock.value;
+	    clock.f.m1_divider = mode->clock.f.m1_divider;
+	    clock.f.m1_shift = mode->clock.f.m1_shift;
+	    SMI501_SetClock(pSmi, mode->current_clock, pll, clock.value);
+	}
 
 	WRITE_SCR(pSmi, MISC_CTL, mode->misc_ctl.value);
 
@@ -469,7 +461,7 @@ SMI501_FindClock(double clock, int32_t max_divider, Bool has1xclck,
 	 multiplier += 2, mclk  = multiplier * 24 * 1000.0) {
 	for (divider = 1; divider <= max_divider; divider += 2) {
 	    for (shift = 0; shift < 8; shift++) {
-		/* Divider 1 not in specs form cards older then 502 */
+		/* Divider 1 not in specs for cards older then 502 */
 		for (xclck = 1; xclck >= !has1xclck; xclck--) {
 		    diff = (mclk / (divider << shift << xclck)) - clock;
 		    if (fabs(diff) < best) {
@@ -497,6 +489,42 @@ SMI501_FindClock(double clock, int32_t max_divider, Bool has1xclck,
 }
 
 double
+SMI501_FindMemClock(double clock, int32_t *x1_select,
+		    int32_t *x1_divider, int32_t *x1_shift)
+{
+    double	diff, best, mclk;
+    int32_t	multiplier, divider, shift;
+
+    best = 0x7fffffff;
+    for (multiplier = 12, mclk  = multiplier * 24 * 1000.0;
+	 mclk <= 14 * 24 * 1000.0;
+	 multiplier += 2, mclk = multiplier * 24 * 1000.0) {
+	for (divider = 1; divider <= 3; divider += 2) {
+	    for (shift = 0; shift < 8; shift++) {
+		diff = (mclk / (divider << shift)) - clock;
+		if (fabs(diff) < best) {
+		    *x1_shift = shift;
+		    *x1_divider = divider == 1 ? 0 : 1;
+		    *x1_select = mclk == 12 * 24 * 1000.0 ? 0 : 1;
+
+		    /* Remember best diff */
+		    best = fabs(diff);
+		}
+	    }
+	}
+    }
+
+    xf86ErrorFVerb(VERBLEV,
+		   "\tMatching clock %5.2f, diff %5.2f (%d/%d/%d)\n",
+		   ((*x1_select ? 14 : 12) * 24 * 1000.0) /
+		   ((*x1_divider == 0 ? 1 : 3) << *x1_shift),
+		    best, *x1_shift, *x1_divider, *x1_select);
+
+    return (best);
+}
+
+
+double
 SMI501_FindPLLClock(double clock, int32_t *m, int32_t *n, int32_t *xclck)
 {
     int32_t	M, N, K;
diff --git a/src/smi_501.h b/src/smi_501.h
index c79b75c..378a99a 100644
--- a/src/smi_501.h
+++ b/src/smi_501.h
@@ -1011,6 +1011,8 @@ void SMI501_PrintRegs(ScrnInfoPtr pScrn);
 double SMI501_FindClock(double clock, int max_divider, Bool has1xclck,
 			       int32_t *x2_1xclck, int32_t *x2_select,
 			       int32_t *x2_divider, int32_t *x2_shift);
+double SMI501_FindMemClock(double clock, int32_t *x1_select,
+			   int32_t *x1_divider, int32_t *x1_shift);
 double SMI501_FindPLLClock(double clock, int32_t *m, int32_t *n,
 				  int32_t *xclck);
 void SMI501_WaitVSync(SMIPtr pSmi, int vsync_count);
diff --git a/src/smi_driver.c b/src/smi_driver.c
index e251448..b36fc7f 100644
--- a/src/smi_driver.c
+++ b/src/smi_driver.c
@@ -150,6 +150,7 @@ typedef enum
     OPTION_PCI_RETRY,
     OPTION_NOACCEL,
     OPTION_MCLK,
+    OPTION_MXCLK,
     OPTION_SWCURSOR,
     OPTION_HWCURSOR,
     OPTION_VIDEOKEY,
@@ -171,7 +172,8 @@ static const OptionInfoRec SMIOptions[] =
     { OPTION_PCI_BURST,	     "pci_burst",	  OPTV_BOOLEAN, {0}, TRUE },
     { OPTION_PCI_RETRY,	     "pci_retry",	  OPTV_BOOLEAN, {0}, TRUE },
     { OPTION_NOACCEL,	     "NoAccel",		  OPTV_BOOLEAN, {0}, FALSE },
-    { OPTION_MCLK,	     "set_mclk",	  OPTV_FREQ,	{0}, FALSE },
+    { OPTION_MCLK,	     "MCLK",		  OPTV_FREQ,	{0}, FALSE },
+    { OPTION_MXCLK,	     "MXCLK",		  OPTV_FREQ,	{0}, FALSE },
     { OPTION_HWCURSOR,	     "HWCursor",	  OPTV_BOOLEAN, {0}, TRUE },
     { OPTION_SWCURSOR,	     "SWCursor",	  OPTV_BOOLEAN, {0}, FALSE },
     { OPTION_VIDEOKEY,	     "VideoKey",	  OPTV_INTEGER, {0}, FALSE },
@@ -1194,12 +1196,12 @@ SMI_DetectPanelSize(ScrnInfoPtr pScrn)
 static void
 SMI_DetectMCLK(ScrnInfoPtr pScrn)
 {
-    double	real;
-    int		mclk;
-    SMIPtr	pSmi = SMIPTR(pScrn);
-
-    pSmi->MCLK = 0;
+    double		real;
+    MSOCClockRec	clock;
+    int			mclk, mxclk;
+    SMIPtr		pSmi = SMIPTR(pScrn);
 
+    pSmi->MCLK = pSmi->MXCLK = 0;
     if (xf86GetOptValFreq(pSmi->Options, OPTION_MCLK, OPTUNITS_MHZ, &real)) {
 	pSmi->MCLK = (int)(real * 1000.0);
 	if (!IS_MSOC(pSmi) && pSmi->MCLK > 120000) {
@@ -1211,17 +1213,17 @@ SMI_DetectMCLK(ScrnInfoPtr pScrn)
     }
     mclk = pSmi->MCLK;
 
+    if (IS_MSOC(pSmi)) {
+	clock.value = READ_SCR(pSmi, CURRENT_CLOCK);
+	if (xf86GetOptValFreq(pSmi->Options, OPTION_MXCLK, OPTUNITS_MHZ, &real))
+	    pSmi->MXCLK = (int)(real * 1000.0);
+	mxclk = pSmi->MXCLK;
+    }
+
     if (pSmi->MCLK == 0) {
-	if (IS_MSOC(pSmi)) {
-	    int			clock, shift, divider;
-
-	    /* FIXME this should just read smi_501.h's bitfields... */
-	    clock = READ_SCR(pSmi, CURRENT_CLOCK);
-	    shift = clock & ((1 << 3) - 1);
-	    divider = (clock >> 3) & 1 ? 3 : 1;
-	    clock = clock & (1 << 4) ? 336 : 288;
-	    mclk = (clock / (divider << shift)) * 1000;
-	}
+	if (IS_MSOC(pSmi))
+	    mclk = (clock.f.m_select ? 336 : 288) /
+		((clock.f.m_divider ? 3 : 1) << (unsigned)clock.f.m_shift);
 	else {
 	    unsigned char	shift, m, n;
 
@@ -1243,8 +1245,14 @@ SMI_DetectMCLK(ScrnInfoPtr pScrn)
 	}
     }
 
-    /* FIXME Don't actually set pSmi->MCLK */
     xf86DrvMsg(pScrn->scrnIndex, X_INFO, "MCLK = %1.3f\n", mclk / 1000.0);
+    if (IS_MSOC(pSmi)) {
+	if (pSmi->MXCLK == 0)
+	    mxclk = (clock.f.m1_select ? 336 : 288) /
+		((clock.f.m1_divider ? 3 : 1) << (unsigned)clock.f.m1_shift);
+	xf86DrvMsg(pScrn->scrnIndex, X_INFO, "MXCLK = %1.3f\n",
+		   mxclk / 1000.0);
+    }
 }
 
 static Bool