[fireball] 28448: - Allow pci read/writes during proving BAR's size operation (fixes a read/write of 0xFFFFFF.. memory addresses).

Author: fireball
Date: Tue Aug 21 23:56:22 2007
New Revision: 28448

URL: http://svn.reactos.org/svn/reactos?rev=28448&view=rev
Log:
- Allow pci read/writes during proving BAR's size operation (fixes a read/write of 0xFFFFFF.. memory addresses).

Modified:
    branches/olpc/hal/halx86/generic/olpcpci.c

Modified: branches/olpc/hal/halx86/generic/olpcpci.c
URL: http://svn.reactos.org/svn/reactos/branches/olpc/hal/halx86/generic/olpcpci....
==============================================================================
--- branches/olpc/hal/halx86/generic/olpcpci.c (original)
+++ branches/olpc/hal/halx86/generic/olpcpci.c Tue Aug 21 23:56:22 2007
@@ -172,6 +172,7 @@
 static ULONG zero_loc  =  0;

static int bar_probing = 0;       /* Set after a write of ~0 to a BAR */
+static ULONG bar_offset = 0;      /* what bar */

static ULONG *hdr_addr(const ULONG *hdr, int reg)
 {
@@ -188,7 +189,17 @@
     * BAR0), and don't skip the size mask area.
     */

-	addr = (ULONG)hdr + reg + (bar_probing ? -0x10 : 0x20);
+	if (bar_probing && (bar_offset == reg))
+	{
+		addr = (ULONG)hdr + reg + (bar_probing ? -0x10 : 0x20);
+
+		/* Reset probing for this bar */
+		bar_probing = 0;
+	}
+	else
+	{
+		addr = (ULONG)hdr + reg + 0x20;
+	}

if ( ((ULONG)addr - (ULONG)hdr) >= 0x90 )
     {
@@ -196,7 +207,6 @@
             (ULONG)addr - (ULONG)hdr, bar_probing, reg);
     }

-	bar_probing = 0;
    return (ULONG *)addr;
 }

@@ -261,7 +271,7 @@
    	}
    }

-	ASSERT(len == 1 || len == 2 || len == 4)
+	ASSERT(len == 1 || len == 2 || len == 4);
    RtlCopyMemory(value, addr, len);
 }

@@ -274,14 +284,18 @@
     * Mostly we just discard writes, but if the write is a size probe
     * (i.e. writing ~0 to a BAR), we remember it and arrange to return
     * the appropriate size mask on the next read.  This is cheating
-	 * to some extent, because it depends on the fact that the next
-	 * access after such a write will always be a read to the same BAR.
+	 * to some extent, but it's possible to do intermediate read/writes
+	 * when probing BAR's size now.
     */

if ((reg >= 0x10) && (reg < 0x2c)) {
    	/* Write is to a BAR */
    	if (*(PULONG)value == ~0)
+		{
+			//DbgPrint("OLPC PCI: Probing bar size, devfn %x, reg %x\n", devfn.u.AsULONG, reg);
    		bar_probing = 1;
+			bar_offset = reg;
+		}
    } else {
    	/*
    	 * No warning on writes to ROM BAR, CMD, LATENCY_TIMER,
@@ -289,6 +303,8 @@
    	 */
    	if ((reg != 0x30) && (reg != 0x04) && (reg != 0x0d) &&
    	    (reg != 0x0c) && (reg != 0x44))
+		{
    		DbgPrint("OLPC PCI: Config write to devfn %x reg %x value %x\n", devfn, reg, *value);
+		}
    }
 }