[SeaBIOS] [Qemu-devel] [seabios patch 0/5] dynamic pci i/o windows
Kevin O'Connor
kevin at koconnor.net
Fri May 4 17:37:25 CEST 2012
On Fri, May 04, 2012 at 10:46:00AM -0400, Kevin O'Connor wrote:
> On Fri, May 04, 2012 at 04:01:56PM +0200, Gerd Hoffmann wrote:
> > On 05/04/12 15:18, Kevin O'Connor wrote:
> > > On Fri, May 04, 2012 at 10:21:22AM +0200, Gerd Hoffmann wrote:
> > >> Hi,
> > >>
> > >> This patch series makes the PCI I/O windows runtime-configurable via
> > >> qemu firmware config interface. Main advantage is that we can size and
> > >> shuffle around the PCI i/O windows according to the amount of memory the
> > >> virtual machine has. We don't need a hole for 64bit PCI bars, we can
> > >> just map them above the main memory. The hole for 32bit PCI bars can be
> > >> enlarged for guests with less than 3.5 GB of memory.
> > >
> > > Why pass in a PCI IO range through fw_cfg if SeaBIOS can figure out an
> > > acceptable range from the amount of memory in the machine?
> >
> > Suggestions on how to update the pci host bridge windows in the dsdt then?
>
> Perhaps malloc_high() a struct with the info you need and then create
> an OperationRegion() in the dynamically generated SSDT with the
> address of the struct.
I played with this a little and came up with the below as an example.
-Kevin
diff --git a/src/acpi-dsdt.dsl b/src/acpi-dsdt.dsl
index 4a18617..960f9fb 100644
--- a/src/acpi-dsdt.dsl
+++ b/src/acpi-dsdt.dsl
@@ -132,7 +132,7 @@ DefinitionBlock (
B0EJ, 32,
}
- Name (_CRS, ResourceTemplate ()
+ Name (CRES, ResourceTemplate ()
{
WordBusNumber (ResourceProducer, MinFixed, MaxFixed, PosDecode,
0x0000, // Address Space Granularity
@@ -183,6 +183,18 @@ DefinitionBlock (
0x8000000000, // Address Length
,, , AddressRangeMemory, TypeStatic)
})
+ Method (_CRS, 0)
+ {
+ External (\_SB.BDAT)
+ Field(\_SB.BDAT, DWordAcc, NoLock, Preserve) {
+ VAL1, 32,
+ VAL2, 32,
+ }
+ DBUG("Got")
+ DBUG(VAL1)
+ DBUG(VAL2)
+ Return (CRES)
+ }
}
}
diff --git a/src/acpi.c b/src/acpi.c
index 30888b9..3e0d4da 100644
--- a/src/acpi.c
+++ b/src/acpi.c
@@ -415,7 +415,8 @@ build_ssdt(void)
int length = ((1+3+4)
+ (acpi_cpus * SD_SIZEOF)
+ (1+2+5+(12*acpi_cpus))
- + (6+2+1+(1*acpi_cpus)));
+ + (6+2+1+(1*acpi_cpus))
+ + 17);
u8 *ssdt = malloc_high(sizeof(struct acpi_table_header) + length);
if (! ssdt) {
warn_noalloc();
@@ -477,6 +478,26 @@ build_ssdt(void)
for (i=0; i<acpi_cpus; i++)
*(ssdt_ptr++) = (i < CountCPUs) ? 0x01 : 0x00;
+ // XXX
+ u32 *myval = malloc_high(sizeof(*myval) * 2);
+ myval[0] = 0x1234abcd;
+ myval[1] = 0xdcba8976;
+
+ // build "OperationRegion(BDAT, SystemMemory, 0x12345678, 0x87654321)"
+ *(ssdt_ptr++) = 0x5B; // ExtOpPrefix
+ *(ssdt_ptr++) = 0x80; // OpRegionOp
+ *(ssdt_ptr++) = 'B';
+ *(ssdt_ptr++) = 'D';
+ *(ssdt_ptr++) = 'A';
+ *(ssdt_ptr++) = 'T';
+ *(ssdt_ptr++) = 0x00; // SystemMemory
+ *(ssdt_ptr++) = 0x0C; // DWordPrefix
+ *(u32*)ssdt_ptr = (u32)myval;
+ ssdt_ptr += 4;
+ *(ssdt_ptr++) = 0x0C; // DWordPrefix
+ *(u32*)ssdt_ptr = sizeof(*myval)*2;
+ ssdt_ptr += 4;
+
build_header((void*)ssdt, SSDT_SIGNATURE, ssdt_ptr - ssdt, 1);
//hexdump(ssdt, ssdt_ptr - ssdt);
More information about the SeaBIOS
mailing list