diff options
Diffstat (limited to 'OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPei.c')
| -rw-r--r-- | OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPei.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPei.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPei.c new file mode 100644 index 0000000000..6f35fb4304 --- /dev/null +++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgMmioPei.c @@ -0,0 +1,236 @@ +/** @file
+
+ Stateful and implicitly initialized fw_cfg library implementation.
+
+ Copyright (C) 2013 - 2014, Red Hat, Inc.
+ Copyright (c) 2011 - 2013, Intel Corporation. All rights reserved.<BR>
+ (C) Copyright 2021 Hewlett Packard Enterprise Development LP<BR>
+ Copyright (c) 2024 Loongson Technology Corporation Limited. All rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <Uefi.h>
+
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/QemuFwCfgLib.h>
+
+#include <libfdt.h>
+
+#include "QemuFwCfgLibMmioInternal.h"
+
+/**
+ To get firmware configure selector address.
+
+ @param VOID
+
+ @retval firmware configure selector address
+**/
+UINTN
+EFIAPI
+QemuGetFwCfgSelectorAddress (
+ VOID
+ )
+{
+ QEMU_FW_CFG_RESOURCE *FwCfgResource;
+
+ FwCfgResource = QemuGetFwCfgResourceHob ();
+ ASSERT (FwCfgResource != NULL);
+
+ return FwCfgResource->FwCfgSelectorAddress;
+}
+
+/**
+ To get firmware configure Data address.
+
+ @param VOID
+
+ @retval firmware configure data address
+**/
+UINTN
+EFIAPI
+QemuGetFwCfgDataAddress (
+ VOID
+ )
+{
+ QEMU_FW_CFG_RESOURCE *FwCfgResource;
+
+ FwCfgResource = QemuGetFwCfgResourceHob ();
+ ASSERT (FwCfgResource != NULL);
+
+ return FwCfgResource->FwCfgDataAddress;
+}
+
+/**
+ To get firmware DMA address.
+
+ @param VOID
+
+ @retval firmware DMA address
+**/
+UINTN
+EFIAPI
+QemuGetFwCfgDmaAddress (
+ VOID
+ )
+{
+ QEMU_FW_CFG_RESOURCE *FwCfgResource;
+
+ FwCfgResource = QemuGetFwCfgResourceHob ();
+ ASSERT (FwCfgResource != NULL);
+
+ return FwCfgResource->FwCfgDmaAddress;
+}
+
+RETURN_STATUS
+EFIAPI
+QemuFwCfgInitialize (
+ VOID
+ )
+{
+ VOID *DeviceTreeBase;
+ INT32 Node;
+ INT32 Prev;
+ UINT32 Signature;
+ CONST CHAR8 *Type;
+ INT32 Len;
+ CONST UINT64 *Reg;
+ UINT64 FwCfgSelectorAddress;
+ UINT64 FwCfgSelectorSize;
+ UINT64 FwCfgDataAddress;
+ UINT64 FwCfgDataSize;
+ UINT64 FwCfgDmaAddress;
+ UINT64 FwCfgDmaSize;
+ QEMU_FW_CFG_RESOURCE *FwCfgResource;
+
+ //
+ // Check whether the Qemu firmware configure resources HOB has been created,
+ // if so use the resources in the HOB.
+ //
+ FwCfgResource = QemuGetFwCfgResourceHob ();
+ if (FwCfgResource != NULL) {
+ return RETURN_SUCCESS;
+ }
+
+ DeviceTreeBase = (VOID *)(UINTN)PcdGet64 (PcdDeviceTreeInitialBaseAddress);
+ ASSERT (DeviceTreeBase != NULL);
+ //
+ // Make sure we have a valid device tree blob
+ //
+ ASSERT (fdt_check_header (DeviceTreeBase) == 0);
+
+ //
+ // Create resouce memory
+ //
+ FwCfgResource = AllocateZeroPool (sizeof (QEMU_FW_CFG_RESOURCE));
+ ASSERT (FwCfgResource != NULL);
+
+ for (Prev = 0; ; Prev = Node) {
+ Node = fdt_next_node (DeviceTreeBase, Prev, NULL);
+ if (Node < 0) {
+ break;
+ }
+
+ //
+ // Check for memory node
+ //
+ Type = fdt_getprop (DeviceTreeBase, Node, "compatible", &Len);
+ if ((Type != NULL) &&
+ (AsciiStrnCmp (Type, "qemu,fw-cfg-mmio", Len) == 0))
+ {
+ //
+ // Get the 'reg' property of this node. For now, we will assume
+ // two 8 byte quantities for base and size, respectively.
+ //
+ Reg = fdt_getprop (DeviceTreeBase, Node, "reg", &Len);
+ if ((Reg != 0) && (Len == (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);
+
+ FwCfgResource->FwCfgSelectorAddress = FwCfgSelectorAddress;
+ FwCfgResource->FwCfgDataAddress = FwCfgDataAddress;
+
+ DEBUG ((
+ DEBUG_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 ((DEBUG_INFO, "Found FwCfg DMA @ 0x%Lx\n", FwCfgDmaAddress));
+ FwCfgResource->FwCfgDmaAddress = FwCfgDmaAddress;
+ } else {
+ FwCfgDmaAddress = 0;
+ }
+
+ if ((FwCfgSelectorAddress != 0) && (FwCfgDataAddress != 0)) {
+ //
+ // Select Item Signature
+ //
+ MmioWrite16 (FwCfgSelectorAddress, SwapBytes16 ((UINT16)QemuFwCfgItemSignature));
+
+ //
+ // Readout the Signature.
+ //
+ Signature = MmioRead32 (FwCfgDataAddress);
+
+ if (Signature == SIGNATURE_32 ('Q', 'E', 'M', 'U')) {
+ //
+ // Build the firmware configure resource HOB.
+ //
+ QemuBuildFwCfgResourceHob (FwCfgResource);
+ } else {
+ FwCfgResource->FwCfgDataAddress = 0;
+ FwCfgResource->FwCfgSelectorAddress = 0;
+ FwCfgResource->FwCfgDmaAddress = 0;
+
+ DEBUG ((
+ DEBUG_ERROR,
+ "%a: Signature dose not match QEMU!\n",
+ __func__
+ ));
+ break;
+ }
+ }
+
+ break;
+ } else {
+ DEBUG ((
+ DEBUG_ERROR,
+ "%a: Failed to parse FDT QemuCfg node\n",
+ __func__
+ ));
+ break;
+ }
+ }
+ }
+
+ return RETURN_SUCCESS;
+}
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