X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=blobdiff_plain;f=OvmfPkg%2FLibrary%2FQemuFwCfgLib%2FQemuFwCfgLib.c;h=a228c029dfb909edadb3247017264c182ea6f0e7;hp=3c5963f31b52ecfe1ec7f1671f558cd15425ed4b;hb=2b631390f9f5f6971c3c8a7f0f47160b80cf072b;hpb=2ce7e221e70214b094e2e54d0e6dc9491a742dd3

diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
index 3c5963f31b..a228c029df 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
@@ -2,6 +2,7 @@
 
   Copyright (c) 2011 - 2013, Intel Corporation. All rights reserved.<BR>
   Copyright (C) 2013, Red Hat, Inc.
+  Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
 
   This program and the accompanying materials
   are licensed and made available under the terms and conditions of the BSD License
@@ -22,58 +23,7 @@
 #include <Library/MemoryAllocationLib.h>
 #include <Library/UefiBootServicesTableLib.h>
 
-
-/**
-  Reads an 8-bit I/O port fifo into a block of memory.
-
-  Reads the 8-bit I/O fifo port specified by Port.
-
-  The port is read Count times, and the read data is
-  stored in the provided Buffer.
-
-  This function must guarantee that all I/O read and write operations are
-  serialized.
-
-  If 8-bit I/O port operations are not supported, then ASSERT().
-
-  @param  Port    The I/O port to read.
-  @param  Count   The number of times to read I/O port.
-  @param  Buffer  The buffer to store the read data into.
-
-**/
-VOID
-EFIAPI
-IoReadFifo8 (
-  IN      UINTN                     Port,
-  IN      UINTN                     Count,
-  OUT     VOID                      *Buffer
-  );
-
-/**
-  Writes an 8-bit I/O port fifo from a block of memory.
-
-  Writes the 8-bit I/O fifo port specified by Port.
-
-  The port is written Count times, and the data are obtained
-  from the provided Buffer.
-
-  This function must guarantee that all I/O read and write operations are
-  serialized.
-
-  If 8-bit I/O port operations are not supported, then ASSERT().
-
-  @param  Port    The I/O port to read.
-  @param  Count   The number of times to read I/O port.
-  @param  Buffer  The buffer to store the read data into.
-
-**/
-VOID
-EFIAPI
-IoWriteFifo8 (
-  IN      UINTN                     Port,
-  IN      UINTN                     Count,
-  OUT     VOID                      *Buffer
-  );
+#include "QemuFwCfgLibInternal.h"
 
 
 /**
@@ -96,6 +46,70 @@ QemuFwCfgSelectItem (
 }
 
 
+/**
+  Transfer an array of bytes using the DMA interface.
+
+  @param[in]     Size    Size in bytes to transfer.
+  @param[in,out] Buffer  Buffer to read data into or write data from. May be
+                         NULL if Size is zero.
+  @param[in]     Write   TRUE if writing to fw_cfg from Buffer, FALSE if
+                         reading from fw_cfg into Buffer.
+**/
+VOID
+InternalQemuFwCfgDmaBytes (
+  IN     UINT32   Size,
+  IN OUT VOID     *Buffer OPTIONAL,
+  IN     BOOLEAN  Write
+  )
+{
+  volatile FW_CFG_DMA_ACCESS Access;
+  UINT32                     AccessHigh, AccessLow;
+  UINT32                     Status;
+
+  if (Size == 0) {
+    return;
+  }
+
+  Access.Control = SwapBytes32 (
+                    Write ? FW_CFG_DMA_CTL_WRITE : FW_CFG_DMA_CTL_READ
+                    );
+  Access.Length  = SwapBytes32 (Size);
+  Access.Address = SwapBytes64 ((UINTN)Buffer);
+
+  //
+  // Delimit the transfer from (a) modifications to Access, (b) in case of a
+  // write, from writes to Buffer by the caller.
+  //
+  MemoryFence ();
+
+  //
+  // Start the transfer.
+  //
+  AccessHigh = (UINT32)RShiftU64 ((UINTN)&Access, 32);
+  AccessLow  = (UINT32)(UINTN)&Access;
+  IoWrite32 (0x514, SwapBytes32 (AccessHigh));
+  IoWrite32 (0x518, SwapBytes32 (AccessLow));
+
+  //
+  // Don't look at Access.Control before starting the transfer.
+  //
+  MemoryFence ();
+
+  //
+  // Wait for the transfer to complete.
+  //
+  do {
+    Status = SwapBytes32 (Access.Control);
+    ASSERT ((Status & FW_CFG_DMA_CTL_ERROR) == 0);
+  } while (Status != 0);
+
+  //
+  // After a read, the caller will want to use Buffer.
+  //
+  MemoryFence ();
+}
+
+
 /**
   Reads firmware configuration bytes into a buffer
 
@@ -110,6 +124,10 @@ InternalQemuFwCfgReadBytes (
   IN VOID                   *Buffer  OPTIONAL
   )
 {
+  if (InternalQemuFwCfgDmaIsAvailable () && Size <= MAX_UINT32) {
+    InternalQemuFwCfgDmaBytes ((UINT32)Size, Buffer, FALSE);
+    return;
+  }
   IoReadFifo8 (0x511, Size, Buffer);
 }
 
@@ -158,6 +176,10 @@ QemuFwCfgWriteBytes (
   )
 {
   if (InternalQemuFwCfgIsAvailable ()) {
+    if (InternalQemuFwCfgDmaIsAvailable () && Size <= MAX_UINT32) {
+      InternalQemuFwCfgDmaBytes ((UINT32)Size, Buffer, TRUE);
+      return;
+    }
     IoWriteFifo8 (0x511, Size, Buffer);
   }
 }
@@ -278,11 +300,12 @@ QemuFwCfgFindFile (
     UINT32 FileSize;
     UINT16 FileSelect;
     UINT16 FileReserved;
-    CHAR8  FName[56];
+    CHAR8  FName[QEMU_FW_CFG_FNAME_SIZE];
 
     FileSize     = QemuFwCfgRead32 ();
     FileSelect   = QemuFwCfgRead16 ();
     FileReserved = QemuFwCfgRead16 ();
+    (VOID) FileReserved; /* Force a do-nothing reference. */
     InternalQemuFwCfgReadBytes (sizeof (FName), FName);
 
     if (AsciiStrCmp (Name, FName) == 0) {
@@ -294,3 +317,31 @@ QemuFwCfgFindFile (
 
   return RETURN_NOT_FOUND;
 }
+
+
+/**
+  Determine if S3 support is explicitly enabled.
+
+  @retval  TRUE   if S3 support is explicitly enabled.
+           FALSE  otherwise. This includes unavailability of the firmware
+                  configuration interface.
+**/
+BOOLEAN
+EFIAPI
+QemuFwCfgS3Enabled (
+  VOID
+  )
+{
+  RETURN_STATUS        Status;
+  FIRMWARE_CONFIG_ITEM FwCfgItem;
+  UINTN                FwCfgSize;
+  UINT8                SystemStates[6];
+
+  Status = QemuFwCfgFindFile ("etc/system-states", &FwCfgItem, &FwCfgSize);
+  if (Status != RETURN_SUCCESS || FwCfgSize != sizeof SystemStates) {
+    return FALSE;
+  }
+  QemuFwCfgSelectItem (FwCfgItem);
+  QemuFwCfgReadBytes (sizeof SystemStates, SystemStates);
+  return (BOOLEAN) (SystemStates[3] & BIT7);
+}