dev-arm: Limit number of max PE in GICv3 to 128

This is needed since there is a problem in the memory layout of
VExpress_GEM5_V2 as it is: having 256KB pages is creating overlapping
regions when reserving space for 256 PEs.

GICv3 redistributors: 0x2c010000 - 0x30010000
PCI regions: 0x30000000 - 0x40000000

We fix this by cutting down the number of supported PEs to 128

Change-Id: I6e87f66a6150a441ccba298662b4548a4972dc40
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18392
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

diff --git a/src/dev/arm/RealView.py b/src/dev/arm/RealView.py
index 9086448997e5a3e16f531cbb0216d506b117e8d1..f83f075f646e2262b7c48d68dad33a541c8c8d95 100644 (file)
--- a/src/dev/arm/RealView.py
+++ b/src/dev/arm/RealView.py
@@ -1085,6 +1085,9 @@ class VExpress_GEM5_V1(VExpress_GEM5_V1_Base):
 class VExpress_GEM5_V2_Base(VExpress_GEM5_Base):
     gic = Gicv3(maint_int=ArmPPI(num=25))
 
+    # Limiting to 128 since it will otherwise overlap with PCI space
+    gic.cpu_max = 128
+
     def _on_chip_devices(self):
         return super(VExpress_GEM5_V2_Base,self)._on_chip_devices() + [
                 self.gic,

diff --git a/system/arm/dt/platforms/vexpress_gem5_v2_base.dtsi b/system/arm/dt/platforms/vexpress_gem5_v2_base.dtsi
index 1dc235d7f1532afacf4a34913a5eeabb43e819cd..9cdee856007d6e54e38a42ef5c263e4459722088 100644 (file)
--- a/system/arm/dt/platforms/vexpress_gem5_v2_base.dtsi
+++ b/system/arm/dt/platforms/vexpress_gem5_v2_base.dtsi
@@ -40,9 +40,9 @@
                #interrupt-cells = <0x3>;
                #address-cells = <0x2>;
                interrupt-controller;
-               redistributor-stride = <0x0 0x40000>; // 256kB stride, needed for ARM AVS tests...
+               redistributor-stride = <0x0 0x40000>; // 256kB stride
                reg = <0x0 0x2c000000 0x0 0x10000
-                      0x0 0x2c010000 0x0 0x4000000 // room for 256 redistributors using 128K each (256K strided...)
+                      0x0 0x2c010000 0x0 0x2000000 // room for 128 redistributors using 128K each (256K strided...)
                       0x0 0x0 0x0 0x0>;
                interrupts = <1 9 0xf04>;
                #size-cells = <0x2>;