/**
Get the address of Xen ACPI Root System Description Pointer (RSDP)
structure.
@param RsdpStructurePtr Return pointer to RSDP structure
@return EFI_SUCCESS Find Xen RSDP structure successfully.
@return EFI_NOT_FOUND Don't find Xen RSDP structure.
@return EFI_ABORTED Find Xen RSDP structure, but it's not integrated.
**/
STATIC
EFI_STATUS
EFIAPI
GetXenArmAcpiRsdp (
OUT EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER **RsdpPtr
)
{
EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER *RsdpStructurePtr;
EFI_STATUS Status;
FDT_CLIENT_PROTOCOL *FdtClient;
CONST UINT64 *Reg;
UINT32 RegSize;
UINTN AddressCells, SizeCells;
UINT64 RegBase;
UINT8 Sum;
RsdpStructurePtr = NULL;
FdtClient = NULL;
//
// Get the RSDP structure address from DeviceTree
//
Status = gBS->LocateProtocol (&gFdtClientProtocolGuid, NULL,
(VOID **)&FdtClient);
ASSERT_EFI_ERROR (Status);
Status = FdtClient->FindCompatibleNodeReg (FdtClient, "xen,guest-acpi",
(CONST VOID **)&Reg, &AddressCells, &SizeCells,
&RegSize);
if (EFI_ERROR (Status)) {
DEBUG ((EFI_D_WARN, "%a: No 'xen,guest-acpi' compatible DT node found\n",
__FUNCTION__));
return EFI_NOT_FOUND;
}
ASSERT (AddressCells == 2);
ASSERT (SizeCells == 2);
ASSERT (RegSize == 2 * sizeof (UINT64));
RegBase = SwapBytes64(Reg[0]);
RsdpStructurePtr = (EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER *)RegBase;
if (RsdpStructurePtr && RsdpStructurePtr->Revision >= 2) {
Sum = CalculateSum8 ((CONST UINT8 *)RsdpStructurePtr,
sizeof (EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER));
if (Sum != 0) {
return EFI_ABORTED;
}
}
*RsdpPtr = RsdpStructurePtr;
return EFI_SUCCESS;
}
RETURN_STATUS
EFIAPI
QemuFwCfgInitialize (
VOID
)
{
EFI_STATUS Status;
FDT_CLIENT_PROTOCOL *FdtClient;
CONST UINT64 *Reg;
UINT32 RegSize;
UINTN AddressCells, SizeCells;
UINT64 FwCfgSelectorAddress;
UINT64 FwCfgSelectorSize;
UINT64 FwCfgDataAddress;
UINT64 FwCfgDataSize;
UINT64 FwCfgDmaAddress;
UINT64 FwCfgDmaSize;
Status = gBS->LocateProtocol (&gFdtClientProtocolGuid, NULL,
(VOID **)&FdtClient);
ASSERT_EFI_ERROR (Status);
Status = FdtClient->FindCompatibleNodeReg (FdtClient, "qemu,fw-cfg-mmio",
(CONST VOID **)&Reg, &AddressCells, &SizeCells,
&RegSize);
if (EFI_ERROR (Status)) {
DEBUG ((EFI_D_WARN,
"%a: No 'qemu,fw-cfg-mmio' compatible DT node found (Status == %r)\n",
__FUNCTION__, Status));
return EFI_SUCCESS;
}
ASSERT (AddressCells == 2);
ASSERT (SizeCells == 2);
ASSERT (RegSize == 2 * sizeof (UINT64));
FwCfgDataAddress = SwapBytes64 (Reg[0]);
FwCfgDataSize = 8;
FwCfgSelectorAddress = FwCfgDataAddress + FwCfgDataSize;
FwCfgSelectorSize = 2;
//
// The following ASSERT()s express
//
// Address + Size - 1 <= MAX_UINTN
//
// for both registers, that is, that the last byte in each MMIO range is
// expressible as a MAX_UINTN. The form below is mathematically
// equivalent, and it also prevents any unsigned overflow before the
// comparison.
//
ASSERT (FwCfgSelectorAddress <= MAX_UINTN - FwCfgSelectorSize + 1);
ASSERT (FwCfgDataAddress <= MAX_UINTN - FwCfgDataSize + 1);
mFwCfgSelectorAddress = FwCfgSelectorAddress;
mFwCfgDataAddress = FwCfgDataAddress;
DEBUG ((EFI_D_INFO, "Found FwCfg @ 0x%Lx/0x%Lx\n", FwCfgSelectorAddress,
FwCfgDataAddress));
if (SwapBytes64 (Reg[1]) >= 0x18) {
FwCfgDmaAddress = FwCfgDataAddress + 0x10;
FwCfgDmaSize = 0x08;
//
// See explanation above.
//
ASSERT (FwCfgDmaAddress <= MAX_UINTN - FwCfgDmaSize + 1);
DEBUG ((EFI_D_INFO, "Found FwCfg DMA @ 0x%Lx\n", FwCfgDmaAddress));
} else {
FwCfgDmaAddress = 0;
}
if (InternalQemuFwCfgIsAvailable ()) {
UINT32 Signature;
QemuFwCfgSelectItem (QemuFwCfgItemSignature);
Signature = QemuFwCfgRead32 ();
if (Signature == SIGNATURE_32 ('Q', 'E', 'M', 'U')) {
//
// For DMA support, we require the DTB to advertise the register, and the
// feature bitmap (which we read without DMA) to confirm the feature.
//
if (FwCfgDmaAddress != 0) {
UINT32 Features;
QemuFwCfgSelectItem (QemuFwCfgItemInterfaceVersion);
Features = QemuFwCfgRead32 ();
if ((Features & BIT1) != 0) {
mFwCfgDmaAddress = FwCfgDmaAddress;
InternalQemuFwCfgReadBytes = DmaReadBytes;
}
}
} else {
mFwCfgSelectorAddress = 0;
mFwCfgDataAddress = 0;
}
}
return RETURN_SUCCESS;
}
