ArmPkg/ArmGic: Function to locate the current CPU GIC redistributor

CPU GIC Registributors are located next to each other in the GIC Redistributor
space.
The CPU GIC Redistributor is identified by its CPU affinity Aff3.Aff2.Aff1.Aff0.

This function returns the base address of the GIC Redistributor of
the calling CPU.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
Tested-by: Ard Biesheuvel <ard@linaro.org>
Reviewed-by: Ard Biesheuvel <ard@linaro.org>



git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16873 6f19259b-4bc3-4df7-8a09-765794883524

ArmPkg/Drivers/ArmGic/ArmGicLib.c

@@ -1,6 +1,6 @@
 /** @file
 *
-*  Copyright (c) 2011-2014, ARM Limited. All rights reserved.
+*  Copyright (c) 2011-2015, ARM Limited. All rights reserved.
 *
 *  This program and the accompanying materials
 *  are licensed and made available under the terms and conditions of the BSD License
@@ -14,12 +14,66 @@
 
 #include <Base.h>
 #include <Library/ArmGicLib.h>
+#include <Library/ArmLib.h>
 #include <Library/DebugLib.h>
 #include <Library/IoLib.h>
+#include <Library/PcdLib.h>
 
 #include "GicV2/ArmGicV2Lib.h"
 #include "GicV3/ArmGicV3Lib.h"
 
+/**
+ * Return the base address of the GIC redistributor for the current CPU
+ *
+ * @param Revision  GIC Revision. The GIC redistributor might have a different
+ *                  granularity following the GIC revision.
+ *
+ * @retval Base address of the associated GIC Redistributor
+ */
+STATIC
+UINTN
+GicGetCpuRedistributorBase (
+  IN UINTN                 GicRedistributorBase,
+  IN ARM_GIC_ARCH_REVISION Revision
+  )
+{
+  UINTN Index;
+  UINTN MpId;
+  UINTN CpuAffinity;
+  UINTN Affinity;
+  UINTN GicRedistributorGranularity;
+  UINTN GicCpuRedistributorBase;
+
+  MpId = ArmReadMpidr ();
+  // Define CPU affinity as Affinity0[0:8], Affinity1[9:15], Affinity2[16:23], Affinity3[24:32]
+  // whereas Affinity3 is defined at [32:39] in MPIDR
+  CpuAffinity = (MpId & (ARM_CORE_AFF0 | ARM_CORE_AFF1 | ARM_CORE_AFF2)) | ((MpId & ARM_CORE_AFF3) >> 8);
+
+  if (Revision == ARM_GIC_ARCH_REVISION_3) {
+    // 2 x 64KB frame: Redistributor control frame + SGI Control & Generation frame
+    GicRedistributorGranularity = ARM_GICR_CTLR_FRAME_SIZE + ARM_GICR_SGI_PPI_FRAME_SIZE;
+  } else {
+    ASSERT_EFI_ERROR (EFI_UNSUPPORTED);
+    return 0;
+  }
+
+  GicCpuRedistributorBase = GicRedistributorBase;
+
+  for (Index = 0; Index < PcdGet32 (PcdCoreCount); Index++) {
+    Affinity = MmioRead64 (GicCpuRedistributorBase + ARM_GICR_TYPER) >> 32;
+    if (Affinity == CpuAffinity) {
+      return GicCpuRedistributorBase;
+    }
+
+    // Move to the next GIC Redistributor frame
+    GicRedistributorBase += GicRedistributorGranularity;
+  }
+
+  // The Redistributor has not been found for the current CPU
+  ASSERT_EFI_ERROR (EFI_NOT_FOUND);
+  return 0;
+}
+
 UINTN
 EFIAPI
 ArmGicGetInterfaceIdentification (

ArmPkg/Drivers/ArmGic/ArmGicLib.inf

@@ -1,5 +1,5 @@
 #/* @file
-#  Copyright (c) 2011-2014, ARM Limited. All rights reserved.
+#  Copyright (c) 2011-2015, ARM Limited. All rights reserved.
 #
 #  This program and the accompanying materials
 #  are licensed and made available under the terms and conditions of the BSD License
@@ -42,4 +42,8 @@
 
 [Packages]
   ArmPkg/ArmPkg.dec
+  ArmPlatformPkg/ArmPlatformPkg.dec
   MdePkg/MdePkg.dec
+
+[Pcd]
+  gArmPlatformTokenSpaceGuid.PcdCoreCount

ArmPkg/Drivers/ArmGic/ArmGicSecLib.inf

@@ -1,5 +1,5 @@
 #/* @file
-#  Copyright (c) 2011-2014, ARM Limited. All rights reserved.
+#  Copyright (c) 2011-2015, ARM Limited. All rights reserved.
 #
 #  This program and the accompanying materials
 #  are licensed and made available under the terms and conditions of the BSD License
@@ -45,3 +45,6 @@
   ArmLib
   DebugLib
   IoLib
+
+[Pcd]
+  gArmPlatformTokenSpaceGuid.PcdCoreCount