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From: Michael Zimmermann <sigmaepsilon92@gmail.com>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>,
	 "edk2-devel@lists.01.org" <edk2-devel@lists.01.org>,
	Laszlo Ersek <lersek@redhat.com>, "Cohen, Eugene" <eugene@hp.com>
Subject: Re: [PATCH 22/26] ArmPlatformPkg/PrePi: switch to ASM_FUNC() asm macro
Date: Wed, 31 Aug 2016 11:43:13 +0200	[thread overview]
Message-ID: <CAN9vWDK0DJt4dS9Q8qnT2kz9dCZNJVO1Gv64Ydq1=u3tkZYOsw@mail.gmail.com> (raw)
In-Reply-To: <CAKv+Gu_7vrBBioU6PnnzWkPVTcsD-pi90QB-hyUsdzRqK4XjrQ@mail.gmail.com>

ArmVirtQemuKernel uses ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S which is not
affected by this bug.

as it turns out, only BeagleBoardPkg uses the generic PrePi code.

On Wed, Aug 31, 2016 at 11:14 AM, Ard Biesheuvel <ard.biesheuvel@linaro.org>
wrote:

> On 31 August 2016 at 05:33, Michael Zimmermann <sigmaepsilon92@gmail.com>
> wrote:
> > reviewed should mean tested ;)
> >
>
> Apologies for the breakage. As it turns out, ArmVirtQemuKernel does
> work even with this bug, probably due to the fact that its
> PcdCoreCount == 1 (or simply that it uses the UniCore flavor rather
> than the MPCore flavor of PrePi)
>
> In any case, thanks for tracking this down, and for proposing a fix.
>
> > took me some time to find out why my system currently doesn't boot
> anymore
> > but here's the fix for this commit:
> >
> > diff --git a/ArmPlatformPkg/PrePi/Arm/ModuleEntryPoint.S
> > b/ArmPlatformPkg/PrePi/Arm/ModuleEntryPoint.S
> > index b7127ce..39030da 100644
> > --- a/ArmPlatformPkg/PrePi/Arm/ModuleEntryPoint.S
> > +++ b/ArmPlatformPkg/PrePi/Arm/ModuleEntryPoint.S
> > @@ -101,7 +101,7 @@ _GetStackBase:
> >    sub   r10, r1, r2
> >
> >    // Stack for the secondary core = Number of Cores - 1
> > -  MOV32 (r0, (FixedPcdGet32(PcdCoreCount) - 1) *
> > FixedPcdGet32(PcdCPUCoreSecondaryStackSize))
> > +  MOV32 (r1, (FixedPcdGet32(PcdCoreCount) - 1) *
> > FixedPcdGet32(PcdCPUCoreSecondaryStackSize))^M
> >    sub   r10, r10, r1
> >
> >    // r10 = The base of the MpCore Stacks (primary stack & secondary
> stacks)
> >
> > On Thu, Aug 11, 2016 at 10:38 AM, Leif Lindholm <
> leif.lindholm@linaro.org>
> > wrote:
> >>
> >> On Wed, Aug 10, 2016 at 05:17:58PM +0200, Ard Biesheuvel wrote:
> >> > Annotate functions with ASM_FUNC() so that they are emitted into
> >> > separate sections.
> >>
> >> Also replacing LoadConstantToReg. Add that to commit message and:
> >> Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
> >>
> >> > Contributed-under: TianoCore Contribution Agreement 1.0
> >> > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> >> > ---
> >> >  ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S | 49
> >> > ++++++-------------
> >> >  ArmPlatformPkg/PrePi/Arm/ModuleEntryPoint.S     | 50
> >> > ++++++--------------
> >> >  2 files changed, 29 insertions(+), 70 deletions(-)
> >> >
> >> > diff --git a/ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S
> >> > b/ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S
> >> > index 9538c70a237c..d0530a874726 100644
> >> > --- a/ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S
> >> > +++ b/ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S
> >> > @@ -12,24 +12,10 @@
> >> >  //
> >> >
> >> >  #include <AsmMacroIoLibV8.h>
> >> > -#include <Base.h>
> >> > -#include <Library/PcdLib.h>
> >> > -#include <AutoGen.h>
> >> > -
> >> > -.text
> >> > -.align 3
> >> > -
> >> > -GCC_ASM_IMPORT(ArmPlatformIsPrimaryCore)
> >> > -GCC_ASM_IMPORT(ArmReadMpidr)
> >> > -GCC_ASM_IMPORT(ArmPlatformPeiBootAction)
> >> > -GCC_ASM_IMPORT(ArmPlatformStackSet)
> >> > -GCC_ASM_EXPORT(_ModuleEntryPoint)
> >> > -ASM_GLOBAL ASM_PFX(mSystemMemoryEnd)
> >> >
> >> > -StartupAddr:                  .8byte ASM_PFX(CEntryPoint)
> >> > -ASM_PFX(mSystemMemoryEnd):    .8byte 0
> >> > +ASM_GLOBAL ASM_PFX(mSystemMemoryEnd)
> >> >
> >> > -ASM_PFX(_ModuleEntryPoint):
> >> > +ASM_FUNC(_ModuleEntryPoint)
> >> >    // Do early platform specific actions
> >> >    bl    ASM_PFX(ArmPlatformPeiBootAction)
> >> >
> >> > @@ -49,10 +35,8 @@ _SystemMemoryEndInit:
> >> >    cmp   x1, #0
> >> >    bne   _SetupStackPosition
> >> >
> >> > -  LoadConstantToReg (FixedPcdGet64(PcdSystemMemoryBase), x1)
> >> > -  LoadConstantToReg (FixedPcdGet64(PcdSystemMemorySize), x2)
> >> > -  sub   x2, x2, #1
> >> > -  add   x1, x1, x2
> >> > +  MOV64 (x1, FixedPcdGet64(PcdSystemMemoryBase) +
> >> > FixedPcdGet64(PcdSystemMemorySize) - 1)
> >> > +
> >> >    // Update the global variable
> >> >    adr   x2, mSystemMemoryEnd
> >> >    str   x1, [x2]
> >> > @@ -61,13 +45,13 @@ _SetupStackPosition:
> >> >    // r1 = SystemMemoryTop
> >> >
> >> >    // Calculate Top of the Firmware Device
> >> > -  LoadConstantToReg (FixedPcdGet64(PcdFdBaseAddress), x2)
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdFdSize), x3)
> >> > +  MOV64 (x2, FixedPcdGet64(PcdFdBaseAddress))
> >> > +  MOV32 (x3, FixedPcdGet32(PcdFdSize) - 1)
> >> >    sub   x3, x3, #1
> >> >    add   x3, x3, x2      // x3 = FdTop = PcdFdBaseAddress + PcdFdSize
> >> >
> >> >    // UEFI Memory Size (stacks are allocated in this region)
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryUefiRegionSize),
> x4)
> >> > +  MOV32 (x4, FixedPcdGet32(PcdSystemMemoryUefiRegionSize))
> >> >
> >> >    //
> >> >    // Reserve the memory for the UEFI region (contain stacks on its
> top)
> >> > @@ -98,9 +82,7 @@ _SetupAlignedStack:
> >> >  _SetupOverflowStack:
> >> >    // Case memory at the top of the address space. Ensure the top of
> the
> >> > stack is EFI_PAGE_SIZE
> >> >    // aligned (4KB)
> >> > -  LoadConstantToReg (EFI_PAGE_MASK, x11)
> >> > -  and   x11, x11, x1
> >> > -  sub   x1, x1, x11
> >> > +  and   x1, x1, ~EFI_PAGE_MASK
> >> >
> >> >  _GetBaseUefiMemory:
> >> >    // Calculate the Base of the UEFI Memory
> >> > @@ -109,22 +91,19 @@ _GetBaseUefiMemory:
> >> >  _GetStackBase:
> >> >    // r1 = The top of the Mpcore Stacks
> >> >    // Stack for the primary core = PrimaryCoreStack
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), x2)
> >> > +  MOV32 (x2, FixedPcdGet32(PcdCPUCorePrimaryStackSize))
> >> >    sub   x12, x1, x2
> >> >
> >> >    // Stack for the secondary core = Number of Cores - 1
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCoreCount), x0)
> >> > -  sub   x0, x0, #1
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize),
> x1)
> >> > -  mul   x1, x1, x0
> >> > +  MOV32 (x1, (FixedPcdGet32(PcdCoreCount) - 1) *
> >> > FixedPcdGet32(PcdCPUCoreSecondaryStackSize))
> >> >    sub   x12, x12, x1
> >> >
> >> >    // x12 = The base of the MpCore Stacks (primary stack & secondary
> >> > stacks)
> >> >    mov   x0, x12
> >> >    mov   x1, x10
> >> >    //ArmPlatformStackSet(StackBase, MpId, PrimaryStackSize,
> >> > SecondaryStackSize)
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), x2)
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize),
> x3)
> >> > +  MOV32 (x2, FixedPcdGet32(PcdCPUCorePrimaryStackSize))
> >> > +  MOV32 (x3, FixedPcdGet32(PcdCPUCoreSecondaryStackSize))
> >> >    bl    ASM_PFX(ArmPlatformStackSet)
> >> >
> >> >    // Is it the Primary Core ?
> >> > @@ -140,7 +119,7 @@ _PrepareArguments:
> >> >
> >> >    // Move sec startup address into a data register
> >> >    // Ensure we're jumping to FV version of the code (not boot
> remapped
> >> > alias)
> >> > -  ldr   x4, StartupAddr
> >> > +  ldr   x4, =ASM_PFX(CEntryPoint)
> >> >
> >> >    // Jump to PrePiCore C code
> >> >    //    x0 = MpId
> >> > @@ -150,3 +129,5 @@ _PrepareArguments:
> >> >
> >> >  _NeverReturn:
> >> >    b _NeverReturn
> >> > +
> >> > +ASM_PFX(mSystemMemoryEnd):    .8byte 0
> >> > diff --git a/ArmPlatformPkg/PrePi/Arm/ModuleEntryPoint.S
> >> > b/ArmPlatformPkg/PrePi/Arm/ModuleEntryPoint.S
> >> > index 1311efc5cb2c..b7127ce9fb4c 100644
> >> > --- a/ArmPlatformPkg/PrePi/Arm/ModuleEntryPoint.S
> >> > +++ b/ArmPlatformPkg/PrePi/Arm/ModuleEntryPoint.S
> >> > @@ -12,28 +12,12 @@
> >> >  //
> >> >
> >> >  #include <AsmMacroIoLib.h>
> >> > -#include <Base.h>
> >> > -#include <Library/PcdLib.h>
> >> > -#include <AutoGen.h>
> >> >
> >> >  #include <Chipset/ArmV7.h>
> >> >
> >> > -.text
> >> > -.align 3
> >> > -
> >> > -GCC_ASM_IMPORT(CEntryPoint)
> >> > -GCC_ASM_IMPORT(ArmPlatformIsPrimaryCore)
> >> > -GCC_ASM_IMPORT(ArmReadMpidr)
> >> > -GCC_ASM_IMPORT(ArmPlatformPeiBootAction)
> >> > -GCC_ASM_IMPORT(ArmPlatformStackSet)
> >> > -GCC_ASM_EXPORT(_ModuleEntryPoint)
> >> >  GCC_ASM_EXPORT(mSystemMemoryEnd)
> >> >
> >> > -StartupAddr:       .word  CEntryPoint
> >> > -mSystemMemoryEnd:  .8byte 0
> >> > -
> >> > -
> >> > -ASM_PFX(_ModuleEntryPoint):
> >> > +ASM_FUNC(_ModuleEntryPoint)
> >> >    // Do early platform specific actions
> >> >    bl    ASM_PFX(ArmPlatformPeiBootAction)
> >> >
> >> > @@ -57,10 +41,8 @@ _SystemMemoryEndInit:
> >> >    cmp   r1, #0
> >> >    bne   _SetupStackPosition
> >> >
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryBase), r1)
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdSystemMemorySize), r2)
> >> > -  sub   r2, r2, #1
> >> > -  add   r1, r1, r2
> >> > +  MOV32 (r1, FixedPcdGet32(PcdSystemMemoryBase) +
> >> > FixedPcdGet32(PcdSystemMemorySize) - 1)
> >> > +
> >> >    // Update the global variable
> >> >    adr   r2, mSystemMemoryEnd
> >> >    str   r1, [r2]
> >> > @@ -69,13 +51,12 @@ _SetupStackPosition:
> >> >    // r1 = SystemMemoryTop
> >> >
> >> >    // Calculate Top of the Firmware Device
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdFdBaseAddress), r2)
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdFdSize), r3)
> >> > -  sub   r3, r3, #1
> >> > +  MOV32 (r2, FixedPcdGet32(PcdFdBaseAddress))
> >> > +  MOV32 (r3, FixedPcdGet32(PcdFdSize) - 1)
> >> >    add   r3, r3, r2      // r3 = FdTop = PcdFdBaseAddress + PcdFdSize
> >> >
> >> >    // UEFI Memory Size (stacks are allocated in this region)
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryUefiRegionSize),
> r4)
> >> > +  MOV32 (r4, FixedPcdGet32(PcdSystemMemoryUefiRegionSize))
> >> >
> >> >    //
> >> >    // Reserve the memory for the UEFI region (contain stacks on its
> top)
> >> > @@ -106,9 +87,8 @@ _SetupAlignedStack:
> >> >  _SetupOverflowStack:
> >> >    // Case memory at the top of the address space. Ensure the top of
> the
> >> > stack is EFI_PAGE_SIZE
> >> >    // aligned (4KB)
> >> > -  LoadConstantToReg (EFI_PAGE_MASK, r9)
> >> > -  and   r9, r9, r1
> >> > -  sub   r1, r1, r9
> >> > +  MOV32 (r9, ~EFI_PAGE_MASK & 0xFFFFFFFF)
> >> > +  and   r1, r1, r9
> >> >
> >> >  _GetBaseUefiMemory:
> >> >    // Calculate the Base of the UEFI Memory
> >> > @@ -117,22 +97,19 @@ _GetBaseUefiMemory:
> >> >  _GetStackBase:
> >> >    // r1 = The top of the Mpcore Stacks
> >> >    // Stack for the primary core = PrimaryCoreStack
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2)
> >> > +  MOV32 (r2, FixedPcdGet32(PcdCPUCorePrimaryStackSize))
> >> >    sub   r10, r1, r2
> >> >
> >> >    // Stack for the secondary core = Number of Cores - 1
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCoreCount), r0)
> >> > -  sub   r0, r0, #1
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize),
> r1)
> >> > -  mul   r1, r1, r0
> >> > +  MOV32 (r0, (FixedPcdGet32(PcdCoreCount) - 1) *
> >> > FixedPcdGet32(PcdCPUCoreSecondaryStackSize))
> >> >    sub   r10, r10, r1
> >> >
> >> >    // r10 = The base of the MpCore Stacks (primary stack & secondary
> >> > stacks)
> >> >    mov   r0, r10
> >> >    mov   r1, r8
> >> >    //ArmPlatformStackSet(StackBase, MpId, PrimaryStackSize,
> >> > SecondaryStackSize)
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2)
> >> > -  LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize),
> r3)
> >> > +  MOV32 (r2, FixedPcdGet32(PcdCPUCorePrimaryStackSize))
> >> > +  MOV32 (r3, FixedPcdGet32(PcdCPUCoreSecondaryStackSize))
> >> >    bl    ASM_PFX(ArmPlatformStackSet)
> >> >
> >> >    // Is it the Primary Core ?
> >> > @@ -149,7 +126,7 @@ _PrepareArguments:
> >> >
> >> >    // Move sec startup address into a data register
> >> >    // Ensure we're jumping to FV version of the code (not boot
> remapped
> >> > alias)
> >> > -  ldr   r4, StartupAddr
> >> > +  ldr   r4, =ASM_PFX(CEntryPoint)
> >> >
> >> >    // Jump to PrePiCore C code
> >> >    //    r0 = MpId
> >> > @@ -160,3 +137,4 @@ _PrepareArguments:
> >> >  _NeverReturn:
> >> >    b _NeverReturn
> >> >
> >> > +ASM_PFX(mSystemMemoryEnd):  .8byte 0
> >> > --
> >> > 2.7.4
> >> >
> >> _______________________________________________
> >> edk2-devel mailing list
> >> edk2-devel@lists.01.org
> >> https://lists.01.org/mailman/listinfo/edk2-devel
> >
> >
>


  reply	other threads:[~2016-08-31  9:43 UTC|newest]

Thread overview: 56+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-08-10 15:17 [PATCH 00/26] ARM assembler cleanup series Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 01/26] ArmLib: remove ArmReplaceLiveTranslationEntry() implementation Ard Biesheuvel
2016-08-10 16:56   ` Leif Lindholm
2016-08-10 17:31     ` Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 02/26] ArmPkg: add missing ArmMmuLib resolution to ArmPkg.dsc Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 03/26] ArmPkg/AsmMacroIoLib: remove unused obsolete MMIO and other asm macros Ard Biesheuvel
2016-08-10 17:04   ` Leif Lindholm
2016-08-10 17:26     ` Ard Biesheuvel
2016-08-11  8:23       ` Leif Lindholm
2016-08-10 15:17 ` [PATCH 04/26] ArmPlatformPkg RVCT: drop dependency on GCC macro library Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 05/26] ArmPkg: introduce ASM_FUNC, MOV32/MOV64 and ADRL/LDRL macros Ard Biesheuvel
2016-08-10 18:26   ` Cohen, Eugene
2016-08-10 18:29     ` Ard Biesheuvel
2016-08-10 18:48       ` Cohen, Eugene
2016-08-10 15:17 ` [PATCH 06/26] ArmVirt/PrePi: make jump to CEntryPoint relative Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 07/26] ArmVirtPkg: clean up assembly source files Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 08/26] ArmPkg/ArmSmcLibNull: move to generic C implementation Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 09/26] ArmPkg/ArmCpuLib: switch to ASM_FUNC() asm macro Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 10/26] ArmPkg/ArmGicV3: " Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 11/26] ArmPkg/ArmHvcLib: " Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 12/26] ArmPkg/ArmLib: " Ard Biesheuvel
2016-08-10 19:00   ` Leif Lindholm
2016-08-10 15:17 ` [PATCH 13/26] ArmPkg/ArmMmuLib: " Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 14/26] ArmPkg/ArmSmcLib: " Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 15/26] ArmPkg/BaseMemoryLibSm: " Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 16/26] ArmPkg/BaseMemoryLibVstm: " Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 17/26] ArmPkg/CompilerIntrinsicsLib: " Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 18/26] ArmPkg/SemihostLib: " Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 19/26] BeagleBoardPkg: remove unused Sec.inf module Ard Biesheuvel
2016-08-11  8:34   ` Leif Lindholm
2016-08-10 15:17 ` [PATCH 20/26] BeagleBoardPkg: add missing ArmMmuLib resolution Ard Biesheuvel
2016-08-10 15:17 ` [PATCH 21/26] ArmPlatformPkg/ArmJunoLib: switch to ASM_FUNC() asm macro Ard Biesheuvel
2016-08-11  8:37   ` Leif Lindholm
2016-08-10 15:17 ` [PATCH 22/26] ArmPlatformPkg/PrePi: " Ard Biesheuvel
2016-08-11  8:38   ` Leif Lindholm
2016-08-31  4:33     ` Michael Zimmermann
2016-08-31  9:14       ` Ard Biesheuvel
2016-08-31  9:43         ` Michael Zimmermann [this message]
2016-08-31  9:45           ` Ard Biesheuvel
2016-08-31  9:47       ` Evan Lloyd
2016-08-31  9:52         ` Michael Zimmermann
2016-08-31  9:53           ` Ard Biesheuvel
2016-09-07 11:10       ` Ryan Harkin
2016-09-07 11:59         ` Ard Biesheuvel
2016-09-07 12:18           ` Ryan Harkin
2016-08-10 15:17 ` [PATCH 23/26] ArmPlatformPkg/PrePeiCore: " Ard Biesheuvel
2016-08-11  8:38   ` Leif Lindholm
2016-08-10 15:18 ` [PATCH 24/26] ArmPlatformPkg/ArmVExpressPkg: " Ard Biesheuvel
2016-08-11  8:39   ` Leif Lindholm
2016-08-10 15:18 ` [PATCH 25/26] ArmPlatformPkg/ArmPlatformLibNull: " Ard Biesheuvel
2016-08-11  8:39   ` Leif Lindholm
2016-08-10 15:18 ` [PATCH 26/26] ArmPlatformPkg/ArmPlatformStackLib: " Ard Biesheuvel
2016-08-11  8:42   ` Leif Lindholm
2016-08-11 10:18 ` [PATCH 00/26] ARM assembler cleanup series Leif Lindholm
2016-08-11 11:27   ` Ard Biesheuvel
2016-08-11 11:31     ` Ard Biesheuvel

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