Attachment 2129 Details for Bug 2750 – Patch to fix problems with Linux MTRR setup.

[patch] Patch to fix problems with Linux MTRR setup.

mtrrdiff (text/plain), 4.64 KB, created by Thomas Hellström on 2005-03-16 13:11:12 UTC

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Creator: Thomas Hellström

Created: 2005-03-16 13:11:12 UTC

Size: 4.64 KB

patch

obsolete

>? lnx_video2.c
>? mtrrdiff
>Index: lnx_video.c
>===================================================================
>RCS file: /cvs/xorg/xc/programs/Xserver/hw/xfree86/os-support/linux/lnx_video.c,v
>retrieving revision 1.4
>diff -u -r1.4 lnx_video.c
>--- lnx_video.c	28 Jan 2005 16:12:59 -0000	1.4
>+++ lnx_video.c	16 Mar 2005 20:57:19 -0000
>@@ -178,6 +178,7 @@
> 	struct mtrr_wc_region *	next;
> };
> 
>+
> static struct mtrr_wc_region *
> mtrr_cull_wc_region(int screenNum, unsigned long base, unsigned long size,
> 		      MessageType from)
>@@ -187,8 +188,8 @@
> 	   it. */
> 
> 	struct mtrr_gentry gent;
>-	char buf[20];
> 	struct mtrr_wc_region *wcreturn = NULL, *wcr;
>+	int count, ret=0;
> 
> 	/* Linux 2.0 users should not get a warning without -verbose */
> 	if (!mtrr_open(2))
>@@ -212,23 +213,24 @@
> 		wcr->sentry.type = MTRR_TYPE_WRCOMB;
> 		wcr->added = FALSE;
> 		
>-		/* There is now a nicer ioctl-based way to do this,
>-		   but it isn't in current kernels. */
>-		snprintf(buf, sizeof(buf), "disable=%u\n", gent.regnum);
>-
>-		if (write(mtrr_fd, buf, strlen(buf)) >= 0) {
>+		count = 3;
>+		while (count-- && 
>+		       (ret = ioctl(mtrr_fd, MTRRIOC_KILL_ENTRY, &(wcr->sentry))) < 0);
>+		
>+		if (ret >= 0) {
> 			xf86DrvMsg(screenNum, from,
> 				   "Removed MMIO write-combining range "
> 				   "(0x%lx,0x%lx)\n",
>-				   gent.base, gent.size);
>+				   (unsigned long) gent.base, (unsigned long) gent.size);
> 			wcr->next = wcreturn;
> 			wcreturn = wcr;
>+			gent.regnum--;
> 		} else {
> 			xfree(wcr);
> 			xf86DrvMsgVerb(screenNum, X_WARNING, 0,
> 				   "Failed to remove MMIO "
> 				   "write-combining range (0x%lx,0x%lx)\n",
>-				   gent.base, gent.size);
>+				       gent.base, (unsigned long) gent.size);
> 		}
> 	}
> 	return wcreturn;
>@@ -236,25 +238,64 @@
> 
> 
> static struct mtrr_wc_region *
>+mtrr_remove_offending(int screenNum, unsigned long base, unsigned long size,
>+		      MessageType from)
>+{
>+    struct mtrr_gentry gent;
>+    struct mtrr_wc_region *wcreturn = NULL, **wcr;
>+
>+    if (!mtrr_open(2))
>+	return NULL;
>+
>+    wcr = &wcreturn;
>+    for (gent.regnum = 0; 
>+	 ioctl(mtrr_fd, MTRRIOC_GET_ENTRY, &gent) >= 0;) {
>+	if (gent.type == MTRR_TYPE_WRCOMB
>+	    && ((gent.base >= base && gent.base + gent.size < base + size) || 
>+		(gent.base >  base && gent.base + gent.size <= base + size))) {
>+	    *wcr = mtrr_cull_wc_region(screenNum, gent.base, gent.size, from);
>+	    while(*wcr) {
>+		wcr = &((*wcr)->next);
>+	    }
>+	} else {
>+	    gent.regnum++;
>+	}
>+    }
>+    return wcreturn;
>+}
>+
>+
>+static struct mtrr_wc_region *
> mtrr_add_wc_region(int screenNum, unsigned long base, unsigned long size,
> 		   MessageType from)
> {
>-	struct mtrr_wc_region *wcr;
>+        struct mtrr_wc_region **wcr, *wcreturn, *curwcr;
>+
>+       /*
>+        * There can be only one....
>+        */
>+
>+	wcreturn = mtrr_remove_offending(screenNum, base, size, from);
>+	wcr = &wcreturn;
>+	while (*wcr) {
>+	    wcr = &((*wcr)->next);
>+	} 
> 
> 	/* Linux 2.0 should not warn, unless the user explicitly asks for
> 	   WC. */
>-	if (!mtrr_open(from == X_CONFIG ? 0 : 2))
>-		return NULL;
> 
>-	wcr = xalloc(sizeof(*wcr));
>-	if (!wcr)
>-		return NULL;
>+	if (!mtrr_open(from == X_CONFIG ? 0 : 2))
>+		return wcreturn;
> 
>-	wcr->sentry.base = base;
>-	wcr->sentry.size = size;
>-	wcr->sentry.type = MTRR_TYPE_WRCOMB;
>-	wcr->added = TRUE;
>-	wcr->next = NULL;
>+	*wcr = curwcr = xalloc(sizeof(**wcr));
>+	if (!curwcr)
>+	    return wcreturn;
>+
>+	curwcr->sentry.base = base;
>+	curwcr->sentry.size = size;
>+	curwcr->sentry.type = MTRR_TYPE_WRCOMB;
>+	curwcr->added = TRUE;
>+	curwcr->next = NULL;
> 
> #if SPLIT_WC_REGIONS
> 	/*
>@@ -279,25 +320,26 @@
> 	    if (n_size) {
> 		xf86DrvMsgVerb(screenNum,X_INFO,3,"Splitting WC range: "
> 			       "base: 0x%lx, size: 0x%lx\n",base,size);
>-		wcr->next = mtrr_add_wc_region(screenNum, n_base, n_size,from);
>+		curwcr->next = mtrr_add_wc_region(screenNum, n_base, n_size,from);
> 	    }
>-	    wcr->sentry.size = d_size;
>+	    curwcr->sentry.size = d_size;
> 	} 
> 	
> 	/*****************************************************************/
> #endif /* SPLIT_WC_REGIONS */
> 
>-	if (ioctl(mtrr_fd, MTRRIOC_ADD_ENTRY, &wcr->sentry) >= 0) {
>+	if (ioctl(mtrr_fd, MTRRIOC_ADD_ENTRY, &curwcr->sentry) >= 0) {
> 		/* Avoid printing on every VT switch */
> 		if (xf86ServerIsInitialising()) {
> 			xf86DrvMsg(screenNum, from,
> 				   "Write-combining range (0x%lx,0x%lx)\n",
> 				   base, size);
> 		}
>-		return wcr;
>+		return wcreturn;
> 	}
> 	else {
>-		xfree(wcr);
>+	        *wcr = curwcr->next;
>+		xfree(curwcr);
> 		
> 		/* Don't complain about the VGA region: MTRR fixed
> 		   regions aren't currently supported, but might be in
>@@ -307,7 +349,7 @@
> 				"Failed to set up write-combining range "
> 				"(0x%lx,0x%lx)\n", base, size);
> 		}
>-		return NULL;
>+		return wcreturn;
> 	}
> }
>

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