On x86-based systems Linux determines the presence and the type of floppy drives via a query of a CMOS field. So does SeaBIOS when populating the return data for int 0x13 function 0x08.
Windows doesn't; instead, it requests this information from BIOS via int 0x13/0x08 or through ACPI objects _FDE (Floppy Drive Enumerate) and _FDI (Floppy Drive Information) of the floppy controller object. On UEFI systems only ACPI-based detection is supported. QEMU used not to provide those objects in its ACPI tables; as a result floppy drives were invisible to Windows on UEFI/OVMF. This patch adds those objects to the floppy controller in SSDT, populating them with the information from the respective QEMU objects. Signed-off-by: Roman Kagan <rka...@virtuozzo.com> Cc: "Michael S. Tsirkin" <m...@redhat.com> Cc: Eduardo Habkost <ehabk...@redhat.com> Cc: Igor Mammedov <imamm...@redhat.com> Cc: John Snow <js...@redhat.com> Cc: Kevin Wolf <kw...@redhat.com> Cc: Paolo Bonzini <pbonz...@redhat.com> Cc: Richard Henderson <r...@twiddle.net> Cc: qemu-bl...@nongnu.org Cc: qemu-sta...@nongnu.org --- changes since v4: - re-split out code changes from test data updates changes since v3: - build on top of dynamic FDC0 patch - include test data updates to maintain bisectability changes since v2: - explicit endianness for buffer data - reorder code to reduce conflicts with dynamic DSDT patchset hw/i386/acpi-build.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c index a01e909..7b8de59 100644 --- a/hw/i386/acpi-build.c +++ b/hw/i386/acpi-build.c @@ -38,6 +38,7 @@ #include "hw/acpi/bios-linker-loader.h" #include "hw/loader.h" #include "hw/isa/isa.h" +#include "hw/block/fdc.h" #include "hw/acpi/memory_hotplug.h" #include "hw/mem/nvdimm.h" #include "sysemu/tpm.h" @@ -106,6 +107,13 @@ typedef struct AcpiPmInfo { uint16_t pcihp_io_len; } AcpiPmInfo; +typedef struct AcpiFDInfo { + uint8_t type; + uint8_t cylinders; + uint8_t heads; + uint8_t sectors; +} AcpiFDInfo; + typedef struct AcpiMiscInfo { bool has_hpet; TPMVersion tpm_version; @@ -114,6 +122,7 @@ typedef struct AcpiMiscInfo { uint16_t pvpanic_port; uint16_t applesmc_io_base; bool has_fdc; + AcpiFDInfo fdinfo[2]; } AcpiMiscInfo; typedef struct AcpiBuildPciBusHotplugState { @@ -237,6 +246,7 @@ static void acpi_get_pm_info(AcpiPmInfo *pm) static void acpi_get_misc_info(AcpiMiscInfo *info) { + int i; ISADevice *fdc; info->has_hpet = hpet_find(); @@ -246,6 +256,16 @@ static void acpi_get_misc_info(AcpiMiscInfo *info) fdc = pc_find_fdc0(); info->has_fdc = !!fdc; + if (fdc) { + for (i = 0; i < ARRAY_SIZE(info->fdinfo); i++) { + AcpiFDInfo *fdinfo = &info->fdinfo[i]; + fdinfo->type = isa_fdc_get_drive_type(fdc, i); + if (fdinfo->type < FDRIVE_DRV_NONE) { + isa_fdc_get_drive_geometry(fdc, i, &fdinfo->cylinders, + &fdinfo->heads, &fdinfo->sectors); + } + } + } } /* @@ -935,6 +955,40 @@ static Aml *build_crs(PCIHostState *host, return crs; } +static Aml *build_fdinfo_aml(int idx, AcpiFDInfo *fdinfo) +{ + Aml *dev, *fdi; + + dev = aml_device("FLP%c", 'A' + idx); + + aml_append(dev, aml_name_decl("_ADR", aml_int(idx))); + + fdi = aml_package(0x10); + aml_append(fdi, aml_int(idx)); /* Drive Number */ + aml_append(fdi, + aml_int(cmos_get_fd_drive_type(fdinfo->type))); /* Device Type */ + aml_append(fdi, + aml_int(fdinfo->cylinders - 1)); /* Maximum Cylinder Number */ + aml_append(fdi, aml_int(fdinfo->sectors)); /* Maximum Sector Number */ + aml_append(fdi, aml_int(fdinfo->heads - 1)); /* Maximum Head Number */ + /* SeaBIOS returns the below values for int 0x13 func 0x08 regardless of + * the drive type, so shall we */ + aml_append(fdi, aml_int(0xAF)); /* disk_specify_1 */ + aml_append(fdi, aml_int(0x02)); /* disk_specify_2 */ + aml_append(fdi, aml_int(0x25)); /* disk_motor_wait */ + aml_append(fdi, aml_int(0x02)); /* disk_sector_siz */ + aml_append(fdi, aml_int(0x12)); /* disk_eot */ + aml_append(fdi, aml_int(0x1B)); /* disk_rw_gap */ + aml_append(fdi, aml_int(0xFF)); /* disk_dtl */ + aml_append(fdi, aml_int(0x6C)); /* disk_formt_gap */ + aml_append(fdi, aml_int(0xF6)); /* disk_fill */ + aml_append(fdi, aml_int(0x0F)); /* disk_head_sttl */ + aml_append(fdi, aml_int(0x08)); /* disk_motor_strt */ + + aml_append(dev, aml_name_decl("_FDI", fdi)); + return dev; +} + static void build_ssdt(GArray *table_data, GArray *linker, AcpiCpuInfo *cpu, AcpiPmInfo *pm, AcpiMiscInfo *misc, @@ -1106,6 +1160,8 @@ build_ssdt(GArray *table_data, GArray *linker, aml_append(ssdt, scope); if (misc->has_fdc) { + uint32_t fde_buf[5] = {0, 0, 0, 0, cpu_to_le32(0x2)}; + scope = aml_scope("\\_SB.PCI0.ISA"); dev = aml_device("FDC0"); @@ -1119,6 +1175,18 @@ build_ssdt(GArray *table_data, GArray *linker, AML_TRANSFER8, 2)); aml_append(dev, aml_name_decl("_CRS", crs)); + for (i = 0; i < ARRAY_SIZE(misc->fdinfo); i++) { + AcpiFDInfo *fdinfo = &misc->fdinfo[i]; + if (fdinfo->type != FDRIVE_DRV_NONE) { + fde_buf[i] = cpu_to_le32(0x1); + aml_append(dev, build_fdinfo_aml(i, fdinfo)); + } + } + + aml_append(dev, + aml_name_decl("_FDE", + aml_buffer(sizeof(fde_buf), (uint8_t *) fde_buf))); + aml_append(scope, dev); aml_append(ssdt, scope); } -- 2.5.0