PrmPkg: Add ALLOCATE_CONTEXT_BUFFER_IN_FW build option

There's currently two approaches being considered for how to allocate the
context buffer passed to PRM handlers:

1. The context buffer is allocated and populated in firmware. As such, the
   FW converts all pointers internal to the buffer to virtual memory
   addresses at the virtual address change event. A single context buffer
   pointer is given to the OS via the PRM ACPI table and the OS converts
   this single physical address to a virtual address when it passes the
   context buffer as a pointer to PRM handlers.

2. The context buffer is allocated and populated in the OS. The OS gets
   all the information needed to populate the context buffer from other
   pre-existing resources (mainly physical addresses in the PRM ACPI
   table). The OS converts all the physical addresses to virtual addresses,
   allocates the context buffer instances, and fills in the information.
   The OS passes the context buffer virtual address to PRM handlers.

The prior behavior was (1). The current POR behavior has moved to (2).
Until (2) is used more widely, it can be kept around with fairly minimal
overhead via a build flag in a few places.

So the default behavior is now (2) (the expected permanent behavior) with
(1) easily enabled by defining "ALLOCATE_CONTEXT_BUFFER_IN_FW" in the
compiler defined macros. A DSC define was added in PrmPkg.dsc to set this
compiler macro in the package  build.

At some point in the future, all code (and some peripheral code)
surrounded with this build flag can be removed if (2) is fully
decided upon.

Cc: Andrew Fish <afish@apple.com>
Cc: Kang Gao <kang.gao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Michael Kubacki <michael.kubacki@microsoft.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Benjamin You <benjamin.you@intel.com>
Cc: Liu Yun <yun.y.liu@intel.com>
Cc: Ankit Sinha <ankit.sinha@intel.com>
Cc: Nate DeSimone <nathaniel.l.desimone@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Acked-by: Michael D Kinney <michael.d.kinney@intel.com>
Acked-by: Liming Gao <gaoliming@byosoft.com.cn>
Acked-by: Leif Lindholm <quic_llindhol@quicinc.com>
Reviewed-by: Ankit Sinha <ankit.sinha@intel.com>

1 files changed, 28 insertions, 11 deletions

diff --git a/PrmPkg/PrmConfigDxe/PrmConfigDxe.c b/PrmPkg/PrmConfigDxe/PrmConfigDxe.c
index cb38146bc9..7215c2e1dc 100644
--- a/PrmPkg/PrmConfigDxe/PrmConfigDxe.c
+++ b/PrmPkg/PrmConfigDxe/PrmConfigDxe.c
@@ -28,8 +28,8 @@
 STATIC  UINTN                     mMaxRuntimeMmioRangeCount;

 STATIC  UINTN                     mMaxStaticDataBufferCount;

 

-STATIC  PRM_RUNTIME_MMIO_RANGES   **mRuntimeMmioRanges;

-STATIC  PRM_DATA_BUFFER           ***mStaticDataBuffers;

+GLOBAL_REMOVE_IF_UNREFERENCED STATIC  PRM_RUNTIME_MMIO_RANGES   **mRuntimeMmioRanges;

+GLOBAL_REMOVE_IF_UNREFERENCED STATIC  PRM_DATA_BUFFER           ***mStaticDataBuffers;

 

 /**

   Converts the runtime memory range physical addresses to virtual addresses.

@@ -178,37 +178,41 @@ StoreVirtualMemoryAddressChangePointers (
   )

 {

   EFI_STATUS                  Status;

-  UINTN                       BufferIndex;

   UINTN                       HandleCount;

   UINTN                       HandleIndex;

   UINTN                       RangeIndex;

+#ifdef ALLOCATE_CONTEXT_BUFFER_IN_FW

+  UINTN                       BufferIndex;

   UINTN                       StaticDataBufferIndex;

+  PRM_CONTEXT_BUFFER          *CurrentContextBuffer;

+#endif

   EFI_HANDLE                  *HandleBuffer;

   PRM_CONFIG_PROTOCOL         *PrmConfigProtocol;

-  PRM_CONTEXT_BUFFER          *CurrentContextBuffer;

 

   DEBUG ((DEBUG_INFO, "%a %a - Entry.\n", _DBGMSGID_, __FUNCTION__));

 

   RangeIndex = 0;

+#ifdef ALLOCATE_CONTEXT_BUFFER_IN_FW

   StaticDataBufferIndex = 0;

 

-  mRuntimeMmioRanges = AllocateRuntimeZeroPool (sizeof (*mRuntimeMmioRanges) * mMaxRuntimeMmioRangeCount);

-  if (mRuntimeMmioRanges == NULL && mMaxRuntimeMmioRangeCount > 0) {

+  mStaticDataBuffers = AllocateRuntimeZeroPool (sizeof (*mStaticDataBuffers) * mMaxStaticDataBufferCount);

+  if (mStaticDataBuffers == NULL && mMaxStaticDataBufferCount > 0) {

     DEBUG ((

       DEBUG_ERROR,

-      "  %a %a: Memory allocation for runtime MMIO pointer array failed.\n",

+      "  %a %a: Memory allocation for PRM static data buffer pointer array failed.\n",

       _DBGMSGID_,

       __FUNCTION__

       ));

     ASSERT (FALSE);

     return;

   }

+#endif

 

-  mStaticDataBuffers = AllocateRuntimeZeroPool (sizeof (*mStaticDataBuffers) * mMaxStaticDataBufferCount);

-  if (mStaticDataBuffers == NULL && mMaxStaticDataBufferCount > 0) {

+  mRuntimeMmioRanges = AllocateRuntimeZeroPool (sizeof (*mRuntimeMmioRanges) * mMaxRuntimeMmioRangeCount);

+  if (mRuntimeMmioRanges == NULL && mMaxRuntimeMmioRangeCount > 0) {

     DEBUG ((

       DEBUG_ERROR,

-      "  %a %a: Memory allocation for PRM static data buffer pointer array failed.\n",

+      "  %a %a: Memory allocation for runtime MMIO pointer array failed.\n",

       _DBGMSGID_,

       __FUNCTION__

       ));

@@ -236,6 +240,7 @@ StoreVirtualMemoryAddressChangePointers (
         continue;

       }

 

+#ifdef ALLOCATE_CONTEXT_BUFFER_IN_FW

       for (BufferIndex = 0; BufferIndex < PrmConfigProtocol->ModuleContextBuffers.BufferCount; BufferIndex++) {

         CurrentContextBuffer = &(PrmConfigProtocol->ModuleContextBuffers.Buffer[BufferIndex]);

 

@@ -256,6 +261,7 @@ StoreVirtualMemoryAddressChangePointers (
           mStaticDataBuffers[StaticDataBufferIndex++] = &CurrentContextBuffer->StaticDataBuffer;

         }

       }

+#endif

       if (PrmConfigProtocol->ModuleContextBuffers.RuntimeMmioRanges != NULL) {

         if (RangeIndex >= mMaxRuntimeMmioRangeCount) {

           Status = EFI_BUFFER_TOO_SMALL;

@@ -280,6 +286,7 @@ StoreVirtualMemoryAddressChangePointers (
       __FUNCTION__,

       RangeIndex

       ));

+#ifdef ALLOCATE_CONTEXT_BUFFER_IN_FW

     DEBUG ((

       DEBUG_INFO,

       "  %a %a: %d static buffers saved for future virtual memory conversion.\n",

@@ -287,6 +294,7 @@ StoreVirtualMemoryAddressChangePointers (
       __FUNCTION__,

       StaticDataBufferIndex

       ));

+#endif

   }

 }

 

@@ -388,12 +396,14 @@ PrmConfigVirtualAddressChangeEvent (
 {

   UINTN   Index;

 

+#ifdef ALLOCATE_CONTEXT_BUFFER_IN_FW

   //

   // Convert static data buffer pointers

   //

   for (Index = 0; Index < mMaxStaticDataBufferCount; Index++) {

     gRT->ConvertPointer (0x0, (VOID **) mStaticDataBuffers[Index]);

   }

+#endif

 

   //

   // Convert runtime MMIO ranges

@@ -484,7 +494,7 @@ PrmConfigEndOfDxeNotification (
       if (PrmConfigProtocol->ModuleContextBuffers.RuntimeMmioRanges != NULL) {

         DEBUG ((

           DEBUG_INFO,

-          "    %a %a: Found %d PRM runtime MMIO ranges to convert.\n",

+          "    %a %a: Found %d PRM runtime MMIO ranges.\n",

            _DBGMSGID_,

            __FUNCTION__,

            PrmConfigProtocol->ModuleContextBuffers.RuntimeMmioRanges->Count

@@ -541,6 +551,13 @@ PrmConfigEntryPoint (
                   );

   ASSERT_EFI_ERROR (Status);

 

+  DEBUG ((DEBUG_INFO, "  %a %a: Context buffers will be allocated in ", _DBGMSGID_, __FUNCTION__));

+#ifdef ALLOCATE_CONTEXT_BUFFER_IN_FW

+  DEBUG ((DEBUG_INFO, "firmware.\n"));

+#else

+  DEBUG ((DEBUG_INFO, "the operating system.\n"));

+#endif

+

   //

   // Register a notification function for virtual address change

   //