ArmPlatformPkg/Sec: clean up FP enabling code

UEFI defines that FP support is required on AArch64, whereas many
platforms enable it anyway on Arm. But when it's enabled, C code can
generate instructions targeting FP registers, so:

- move ArmEnableVFP call to asm
- make it unconditional on AArch64

Signed-off-by: Leif Lindholm <leif.lindholm@oss.qualcomm.com>

8 files changed, 22 insertions, 16 deletions

diff --git a/ArmPlatformPkg/PeilessSec/AArch64/ArchPeilessSec.c b/ArmPlatformPkg/PeilessSec/AArch64/ArchPeilessSec.c
index ccc9cde..22148f0 100644
--- a/ArmPlatformPkg/PeilessSec/AArch64/ArchPeilessSec.c
+++ b/ArmPlatformPkg/PeilessSec/AArch64/ArchPeilessSec.c
@@ -18,11 +18,6 @@ ArchInitialize (
   VOID

   )

 {

-  // Enable Floating Point

-  if (FixedPcdGet32 (PcdVFPEnabled)) {

-    ArmEnableVFP ();

-  }

-

   if (ArmReadCurrentEL () == AARCH64_EL2) {

     // Trap General Exceptions. All exceptions that would be routed to EL1 are routed to EL2

     ArmWriteHcr (ARM_HCR_TGE);

diff --git a/ArmPlatformPkg/PeilessSec/AArch64/ModuleEntryPoint.S b/ArmPlatformPkg/PeilessSec/AArch64/ModuleEntryPoint.S
index c6b7093..5f285f3 100644
--- a/ArmPlatformPkg/PeilessSec/AArch64/ModuleEntryPoint.S
+++ b/ArmPlatformPkg/PeilessSec/AArch64/ModuleEntryPoint.S
@@ -11,6 +11,10 @@ ASM_FUNC(_ModuleEntryPoint)
   // Do early platform specific actions

   bl    ASM_PFX(ArmPlatformPeiBootAction)

 

+  // Enable Floating Point. This needs to be done before entering C code, which

+  // may use FP/SIMD registers.

+  bl    ArmEnableVFP

+

 // Check if we can install the stack at the top of the System Memory or if we need

 // to install the stacks at the bottom of the Firmware Device (case the FD is located

 // at the top of the DRAM)

diff --git a/ArmPlatformPkg/PeilessSec/Arm/ArchPeilessSec.c b/ArmPlatformPkg/PeilessSec/Arm/ArchPeilessSec.c
index 3c3cef6..e2f6f67 100644
--- a/ArmPlatformPkg/PeilessSec/Arm/ArchPeilessSec.c
+++ b/ArmPlatformPkg/PeilessSec/Arm/ArchPeilessSec.c
@@ -18,8 +18,4 @@ ArchInitialize (
 {

   // Enable program flow prediction, if supported.

   ArmEnableBranchPrediction ();

-

-  if (FixedPcdGet32 (PcdVFPEnabled)) {

-    ArmEnableVFP ();

-  }

 }

diff --git a/ArmPlatformPkg/PeilessSec/Arm/ModuleEntryPoint.S b/ArmPlatformPkg/PeilessSec/Arm/ModuleEntryPoint.S
index 6b38b86..9043d86 100644
--- a/ArmPlatformPkg/PeilessSec/Arm/ModuleEntryPoint.S
+++ b/ArmPlatformPkg/PeilessSec/Arm/ModuleEntryPoint.S
@@ -13,6 +13,12 @@ ASM_FUNC(_ModuleEntryPoint)
   // Do early platform specific actions

   bl    ASM_PFX(ArmPlatformPeiBootAction)

 

+#if (FixedPcdGet32 (PcdVFPEnabled))

+  // Enable Floating Point. This needs to be done before entering C code, which

+  // may use FP/SIMD registers.

+  bl    ArmEnableVFP

+#endif

+

 // Check if we can install the stack at the top of the System Memory or if we need

 // to install the stacks at the bottom of the Firmware Device (case the FD is located

 // at the top of the DRAM)

diff --git a/ArmPlatformPkg/PeilessSec/PeilessSec.inf b/ArmPlatformPkg/PeilessSec/PeilessSec.inf
index 7f67adf..e210d01 100644
--- a/ArmPlatformPkg/PeilessSec/PeilessSec.inf
+++ b/ArmPlatformPkg/PeilessSec/PeilessSec.inf
@@ -70,9 +70,11 @@
   gArmTokenSpaceGuid.PcdFdSize

   gArmTokenSpaceGuid.PcdFvBaseAddress

   gArmTokenSpaceGuid.PcdFvSize

-  gArmTokenSpaceGuid.PcdVFPEnabled

   gEmbeddedTokenSpaceGuid.PcdPrePiCpuIoSize

 

+[FixedPcd.ARM]

+  gArmTokenSpaceGuid.PcdVFPEnabled

+

 [Pcd]

   gArmTokenSpaceGuid.PcdSystemMemoryBase

   gArmTokenSpaceGuid.PcdSystemMemorySize

diff --git a/ArmPlatformPkg/Sec/Arm/ModuleEntryPoint.S b/ArmPlatformPkg/Sec/Arm/ModuleEntryPoint.S
index 1207497..7cb3de7 100644
--- a/ArmPlatformPkg/Sec/Arm/ModuleEntryPoint.S
+++ b/ArmPlatformPkg/Sec/Arm/ModuleEntryPoint.S
@@ -11,6 +11,12 @@ ASM_FUNC(_ModuleEntryPoint)
   // Do early platform specific actions

   bl    ASM_PFX(ArmPlatformPeiBootAction)

 

+#if (FixedPcdGet32 (PcdVFPEnabled))

+  // Enable Floating Point. This needs to be done before entering C code, which

+  // may use FP/SIMD registers.

+  bl    ArmEnableVFP

+#endif

+

   // Get the top of the primary stacks (and the base of the secondary stacks)

   MOV32 (r1, FixedPcdGet64(PcdCPUCoresStackBase) + FixedPcdGet32(PcdCPUCorePrimaryStackSize))

 

diff --git a/ArmPlatformPkg/Sec/Sec.c b/ArmPlatformPkg/Sec/Sec.c
index 9a700e5..4535ae7 100644
--- a/ArmPlatformPkg/Sec/Sec.c
+++ b/ArmPlatformPkg/Sec/Sec.c
@@ -223,11 +223,6 @@ CEntryPoint (
   ASSERT (((UINTN)PeiVectorTable & ARM_VECTOR_TABLE_ALIGNMENT) == 0);

   ArmWriteVBar ((UINTN)PeiVectorTable);

 

-  // Enable Floating Point

-  if (FixedPcdGet32 (PcdVFPEnabled)) {

-    ArmEnableVFP ();

-  }

-

   // Invoke "ProcessLibraryConstructorList" to have all library constructors

   // called.

   ProcessLibraryConstructorList ();

diff --git a/ArmPlatformPkg/Sec/Sec.inf b/ArmPlatformPkg/Sec/Sec.inf
index b5af19e..a75ce8d 100644
--- a/ArmPlatformPkg/Sec/Sec.inf
+++ b/ArmPlatformPkg/Sec/Sec.inf
@@ -58,9 +58,11 @@
 [FixedPcd]

   gArmTokenSpaceGuid.PcdFvBaseAddress

   gArmTokenSpaceGuid.PcdFvSize

-  gArmTokenSpaceGuid.PcdVFPEnabled

 

   gArmPlatformTokenSpaceGuid.PcdCPUCoresStackBase

   gArmPlatformTokenSpaceGuid.PcdCPUCorePrimaryStackSize

 

   gEfiMdeModulePkgTokenSpaceGuid.PcdInitValueInTempStack

+

+[FixedPcd.ARM]

+  gArmTokenSpaceGuid.PcdVFPEnabled