Add a fw_cfg device node to the ACPI SSDT, on machine types pc-*-2.5 and up. While the guest-side BIOS can't utilize this information (since it has to access the hard-coded fw_cfg device to extract ACPI tables to begin with), having fw_cfg listed in ACPI will help the guest kernel keep a more accurate inventory of in-use IO port regions.
Signed-off-by: Gabriel Somlo <so...@cmu.edu> --- hw/i386/acpi-build.c | 21 +++++++++++++++++++++ hw/i386/pc_piix.c | 1 + hw/i386/pc_q35.c | 1 + include/hw/i386/pc.h | 1 + 4 files changed, 24 insertions(+) diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c index 95e0c65..e3d097b 100644 --- a/hw/i386/acpi-build.c +++ b/hw/i386/acpi-build.c @@ -906,6 +906,7 @@ build_ssdt(GArray *table_data, GArray *linker, PcPciInfo *pci, PcGuestInfo *guest_info) { MachineState *machine = MACHINE(qdev_get_machine()); + PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(machine); uint32_t nr_mem = machine->ram_slots; unsigned acpi_cpus = guest_info->apic_id_limit; Aml *ssdt, *sb_scope, *scope, *pkg, *dev, *method, *crs, *field, *ifctx; @@ -1071,6 +1072,26 @@ build_ssdt(GArray *table_data, GArray *linker, aml_append(scope, aml_name_decl("_S5", pkg)); aml_append(ssdt, scope); + if (!pcmc->acpi_no_fw_cfg_node) { + scope = aml_scope("\\_SB"); + dev = aml_device("FWCF"); + + aml_append(dev, aml_name_decl("_HID", aml_string("QEMU0002"))); + + crs = aml_resource_template(); + /* when using port i/o, the 8-bit data register *always* overlaps + * with half of the 16-bit control register. Hence, the total size + * of the i/o region used is FW_CFG_CTL_SIZE */ + aml_append(crs, + aml_io(AML_DECODE16, FW_CFG_IO_BASE, FW_CFG_IO_BASE, + 0x01, FW_CFG_CTL_SIZE) + ); + aml_append(dev, aml_name_decl("_CRS", crs)); + + aml_append(scope, dev); + aml_append(ssdt, scope); + } + if (misc->applesmc_io_base) { scope = aml_scope("\\_SB.PCI0.ISA"); dev = aml_device("SMC"); diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c index 3f925b2..003c28a 100644 --- a/hw/i386/pc_piix.c +++ b/hw/i386/pc_piix.c @@ -467,6 +467,7 @@ static void pc_i440fx_2_4_machine_options(MachineClass *m) PCMachineClass *pcmc = PC_MACHINE_CLASS(m); pc_i440fx_machine_options(m); pcmc->broken_reserved_end = true; + pcmc->acpi_no_fw_cfg_node = true; m->default_machine_opts = "firmware=bios-256k.bin"; m->default_display = "std"; m->alias = "pc"; diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c index 11601ab..c4656f1 100644 --- a/hw/i386/pc_q35.c +++ b/hw/i386/pc_q35.c @@ -371,6 +371,7 @@ static void pc_q35_2_4_machine_options(MachineClass *m) PCMachineClass *pcmc = PC_MACHINE_CLASS(m); pc_q35_machine_options(m); pcmc->broken_reserved_end = true; + pcmc->acpi_no_fw_cfg_node = true; m->default_machine_opts = "firmware=bios-256k.bin"; m->default_display = "std"; m->no_floppy = 1; diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h index fadcaa4..2955bd9 100644 --- a/include/hw/i386/pc.h +++ b/include/hw/i386/pc.h @@ -62,6 +62,7 @@ struct PCMachineClass { bool broken_reserved_end; HotplugHandler *(*get_hotplug_handler)(MachineState *machine, DeviceState *dev); + bool acpi_no_fw_cfg_node; }; #define TYPE_PC_MACHINE "generic-pc-machine" -- 2.4.3