[PATCH v3 04/27] ArmVirtualizationPkg: add GICv3 detection to VirtFdtDxe

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

This adds support for detecting the presence of a GICv3 interrupt
controller from the device tree, and recording its distributor and
redistributor base addresses in their respective PCDs.

Contributed-under: TianoCore Contribution Agreement 1.0
Acked-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---

Removed Olivier's R-b due to the fact that this patch was changed to
accomodate pending but not yet finalized changes to the GICv3 driver.
I think that recording the distributor and redistributor base addresses
should be sufficient in any case, but we may have to revisit this still
when the GIC dust settles.
 
 .../ArmVirtualizationPkg/ArmVirtualizationQemu.dsc |  1 +
 .../ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.c   | 31 +++++++++++++++++++++-
 .../ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.inf |  1 +
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/ArmPlatformPkg/ArmVirtualizationPkg/ArmVirtualizationQemu.dsc b/ArmPlatformPkg/ArmVirtualizationPkg/ArmVirtualizationQemu.dsc
index 32c8deb3b1d6..f38ffd034a59 100644
--- a/ArmPlatformPkg/ArmVirtualizationPkg/ArmVirtualizationQemu.dsc
+++ b/ArmPlatformPkg/ArmVirtualizationPkg/ArmVirtualizationQemu.dsc
@@ -172,6 +172,7 @@
   # ARM General Interrupt Controller
   #
   gArmTokenSpaceGuid.PcdGicDistributorBase|0x0
+  gArmTokenSpaceGuid.PcdGicRedistributorBase|0x0
   gArmTokenSpaceGuid.PcdGicInterruptInterfaceBase|0x0
 
   ## PL031 RealTimeClock
diff --git a/ArmPlatformPkg/ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.c b/ArmPlatformPkg/ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.c
index 1d44f9ba02b3..e8bbea0847c0 100644
--- a/ArmPlatformPkg/ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.c
+++ b/ArmPlatformPkg/ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.c
@@ -46,6 +46,7 @@ typedef enum {
   PropertyTypeTimer,
   PropertyTypePsci,
   PropertyTypeFwCfg,
+  PropertyTypeGicV3,
 } PROPERTY_TYPE;
 
 typedef struct {
@@ -62,6 +63,7 @@ STATIC CONST PROPERTY CompatibleProperties[] = {
   { PropertyTypeTimer,   "arm,armv8-timer"     },
   { PropertyTypePsci,    "arm,psci-0.2"        },
   { PropertyTypeFwCfg,   "qemu,fw-cfg-mmio"    },
+  { PropertyTypeGicV3,   "arm,gic-v3"          },
   { PropertyTypeUnknown, ""                    }
 };
 
@@ -114,7 +116,7 @@ InitializeVirtFdtDxe (
   VIRTIO_TRANSPORT_DEVICE_PATH   *DevicePath;
   EFI_HANDLE                     Handle;
   UINT64                         RegBase;
-  UINT64                         DistBase, CpuBase;
+  UINT64                         DistBase, CpuBase, RedistBase;
   CONST INTERRUPT_PROPERTY       *InterruptProp;
   INT32                          SecIntrNum, IntrNum, VirtIntrNum, HypIntrNum;
   CONST CHAR8                    *PsciMethod;
@@ -256,6 +258,33 @@ InitializeVirtFdtDxe (
       DEBUG ((EFI_D_INFO, "Found GIC @ 0x%Lx/0x%Lx\n", DistBase, CpuBase));
       break;
 
+    case PropertyTypeGicV3:
+      //
+      // The GIC v3 DT binding describes a series of at least 3 physical base
+      // addresses: the distributor interface (GICD), at least one redistributor
+      // interface (GICR) and the CPU interface (GICC).
+      // Under virtualization, we assume that the first redistributor interface
+      // listed covers the boot CPU. Also, our GICv3 driver only supports the
+      // system register CPU interface, so we can safely ignore the MMIO version
+      // which is listed after the sequence of redistributor interfaces.
+      // This means we are only interested in the first two memory regions
+      // supplied, and ignore everything else.
+      //
+      ASSERT (Len >= 32);
+
+      DistBase = fdt64_to_cpu (((UINT64 *)RegProp)[0]);
+      ASSERT (DistBase < MAX_UINT32);
+
+      RedistBase = fdt64_to_cpu (((UINT64 *)RegProp)[2]);
+      ASSERT (RedistBase < MAX_UINT32);
+
+      PcdSet32 (PcdGicDistributorBase, (UINT32)DistBase);
+      PcdSet32 (PcdGicRedistributorBase, (UINT32)RedistBase);
+
+      DEBUG ((EFI_D_INFO, "Found GIC v3 (re)distributor @ 0x%Lx (0x%Lx)\n",
+        DistBase, RedistBase));
+      break;
+
     case PropertyTypeRtc:
       ASSERT (Len == 16);
 
diff --git a/ArmPlatformPkg/ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.inf b/ArmPlatformPkg/ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.inf
index 514ce2fdf658..dbf0f8eb54bc 100644
--- a/ArmPlatformPkg/ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.inf
+++ b/ArmPlatformPkg/ArmVirtualizationPkg/VirtFdtDxe/VirtFdtDxe.inf
@@ -51,6 +51,7 @@
   gArmVirtualizationTokenSpaceGuid.PcdFwCfgSelectorAddress
   gArmVirtualizationTokenSpaceGuid.PcdFwCfgDataAddress
   gArmTokenSpaceGuid.PcdGicDistributorBase
+  gArmTokenSpaceGuid.PcdGicRedistributorBase
   gArmTokenSpaceGuid.PcdGicInterruptInterfaceBase
   gArmTokenSpaceGuid.PcdArmArchTimerSecIntrNum
   gArmTokenSpaceGuid.PcdArmArchTimerIntrNum
-- 
1.8.3.2