hvmloader: don't use AML operations on 64-bit fields

WinXP and Win2K3, while having no problem with the QWordMemory resource
(there was another one there before), don't like operations on 64-bit
fields. Split the fields d0688669 ("hvmloader: also cover PCI MMIO
ranges above 4G with UC MTRR ranges") added to 32-bit ones, handling
carry over explicitly.

Sadly the constructs needed to create the sub-fields - nominally

    CreateDWordField(PRT0, \_SB.PCI0._CRS._Y02._MIN, MINL)
    CreateDWordField(PRT0, Add(\_SB.PCI0._CRS._Y02._MIN, 4), MINH)

- can't be used: The former gets warned upon by newer iasl, i.e. would
need to be replaced by the latter just with the addend changed to 0,
and the latter doesn't translate properly with recent iasl). Hence,
short of having an ASL/iasl expert at hand, we need to work around the
shortcomings of various iasl versions. See the code comment.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
---
v2: Avoid mis-compilation and warnings issued by newer iasl.

--- a/tools/firmware/hvmloader/acpi/dsdt.asl
+++ b/tools/firmware/hvmloader/acpi/dsdt.asl
@@ -57,8 +57,10 @@ DefinitionBlock ("DSDT.aml", "DSDT", 2, 
            MSUA, 32, /* MADT checksum address */
            MAPA, 32, /* MADT LAPIC0 address */
            VGIA, 32, /* VM generation id address */
-           HMIN, 64,
-           HLEN, 64
+           LMIN, 32,
+           HMIN, 32,
+           LLEN, 32,
+           HLEN, 32
        }
 
         /* Fix HCT test for 0x400 pci memory:
@@ -176,15 +178,41 @@ DefinitionBlock ("DSDT.aml", "DSDT", 2, 
                 Add(MMIN, MLEN, MMAX)
                 Subtract(MMAX, One, MMAX)
 
-                CreateQWordField(PRT0, \_SB.PCI0._CRS._Y02._MIN, HMIN)
-                CreateQWordField(PRT0, \_SB.PCI0._CRS._Y02._MAX, HMAX)
-                CreateQWordField(PRT0, \_SB.PCI0._CRS._Y02._LEN, HLEN)
-
-                Store(\_SB.HMIN, HMIN)
-                Store(\_SB.HLEN, HLEN)
-                Add(HMIN, HLEN, HMAX)
-                If(LOr(HMIN, HLEN)) {
-                    Subtract(HMAX, One, HMAX)
+                /*
+                 * WinXP / Win2K3 blue-screen for operations on 64-bit values.
+                 * Therefore we need to split the 64-bit calculations needed
+                 * here, but different iasl versions evaluate name references
+                 * to integers differently:
+                 * Year (approximate)          2006    2008    2012
+                 * \_SB.PCI0._CRS._Y02         zero   valid   valid
+                 * \_SB.PCI0._CRS._Y02._MIN   valid   valid    huge
+                 */
+                If(LEqual(Zero, \_SB.PCI0._CRS._Y02)) {
+                    Subtract(\_SB.PCI0._CRS._Y02._MIN, 14, Local0)
+                } Else {
+                    Store(\_SB.PCI0._CRS._Y02, Local0)
+                }
+                CreateDWordField(PRT0, Add(Local0, 14), MINL)
+                CreateDWordField(PRT0, Add(Local0, 18), MINH)
+                CreateDWordField(PRT0, Add(Local0, 22), MAXL)
+                CreateDWordField(PRT0, Add(Local0, 26), MAXH)
+                CreateDWordField(PRT0, Add(Local0, 38), LENL)
+                CreateDWordField(PRT0, Add(Local0, 42), LENH)
+
+                Store(\_SB.LMIN, MINL)
+                Store(\_SB.HMIN, MINH)
+                Store(\_SB.LLEN, LENL)
+                Store(\_SB.HLEN, LENH)
+                Add(MINL, LENL, MAXL)
+                Add(MINH, LENH, MAXH)
+                If(LLess(MAXL, MINL)) {
+                    Add(MAXH, One, MAXH)
+                }
+                If(LOr(MINH, LENL)) {
+                    If(LEqual(MAXL, 0)) {
+                        Subtract(MAXH, One, MAXH)
+                    }
+                    Subtract(MAXL, One, MAXL)
                 }
 
                 Return (PRT0)