Re: [edk2-devel] [PATCH V3 3/3] OvmfPkg: Move LocalApicTimerDxe to UefiCpuPkg
Hi, > > 2. Can SourceLevelDebug (rely on Local APIC timer) work if this driver is > > chosen as DXE timer driver? > After checking the code and running the PoC (enable SourceLevelDebug and > LocalApicTimerDxe), I find this driver doesn't work anymore. > Actually it asserts in > https://github.com/mxu9/edk2/blob/ovmf_lapic_timer.v3/UefiCpuPkg/LocalApicTimerDxe/LocalApicTimerDxe.c#L334 Hmm, I guess this makes LocalApicTimerDxe alot less useful on physical hardware. So keep it in OvmdPkg? For virtual machines there are other debugging options, using qemu's builtin gdb server for example, so SourceLevelDebug not being available isn't a big issue IMHO. > For TDVF we assume SourceLevelDebug is not supported. So LocalApicTimerDxe is > still working for TDVF. > > For other VM guests in OvmfPkg, can we assume SourceLevelDebug is NOT > supported after LocalApicTimer is used (the older timer is 8254)? > @ Gerd Hoffmann (OvmfPkg) Fine with me. > @ Anthony Perard , Julien Grall (Xen) Xen already uses the apic timer today, so that shouldn't be a problem either ;) take care, Gerd -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#83930): https://edk2.groups.io/g/devel/message/83930 Mute This Topic: https://groups.io/mt/86900367/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
Re: [edk2-devel] [PATCH V3 3/3] OvmfPkg: Move LocalApicTimerDxe to UefiCpuPkg
On November 22, 2021 11:05 AM, Ni Ray wrote: > Min, > What's the reason of moving this driver to UefiCpuPkg? Please refer to the discussion in https://edk2.groups.io/g/devel/topic/86735078#83126 Because localApicTimerDxe is hardware feature. There is no specific OVMF or QEMU related thing there. It does not make sense to keep it to OvmfPkg. > > When the LocalApicTimerDxe is in OvmfPkg, it's clear that this driver is only > used by OVMF/QEMU platform. > Now since the patch moves the driver to UefiCpuPkg, it's possible that other > platforms may choose this driver as the timer driver in DXE phase. > > So, we need to make sure the quality of this driver is good enough for a > broad scope of platforms. > > 1. What's the issue when this driver still stays in OvmfPkg? If it's a must > that > this driver stays in UefiCpuPkg, please help to address following questions: > > 2. Can SourceLevelDebug (rely on Local APIC timer) work if this driver is > chosen as DXE timer driver? After checking the code and running the PoC (enable SourceLevelDebug and LocalApicTimerDxe), I find this driver doesn't work anymore. Actually it asserts in https://github.com/mxu9/edk2/blob/ovmf_lapic_timer.v3/UefiCpuPkg/LocalApicTimerDxe/LocalApicTimerDxe.c#L334 For TDVF we assume SourceLevelDebug is not supported. So LocalApicTimerDxe is still working for TDVF. For other VM guests in OvmfPkg, can we assume SourceLevelDebug is NOT supported after LocalApicTimer is used (the older timer is 8254)? @Gerd Hoffmann (OvmfPkg) @ Rebecca Cran, @ Peter Grehan (Bhyve) @ Tom Lendacky, @Brijesh Singh (Sev) @ Anthony Perard , Julien Grall (Xen) This limitation will be documented in LocalApicTimerDxe.inf so that the user of this timer driver is aware of it. > 3. Can detailed comments be added for " @bug : This does not handle > missed timer interrupts" in TimerInterruptHandler()? Sure. More comments will be added. > 4. Can detailed comments be added for " DisableInterrupts ();" in > TimerInterruptHandler()? Sure. More comments will be added. > 5. In general what kinds of platforms are capable of using this driver as > Timer > driver? Platforms that support local Apic are capable of using this driver. > Thanks Min -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#83929): https://edk2.groups.io/g/devel/message/83929 Mute This Topic: https://groups.io/mt/86900367/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
Re: [edk2-devel] [PATCH V3 3/3] OvmfPkg: Move LocalApicTimerDxe to UefiCpuPkg
Thanks Ray.
I prefer to put the LocalApicTimerDxe to UefiCpuPkg, because it is hardware
feature.
There is no specific OVMF or QEMU related thing there. It does not make sense
to keep it to OvmfPkg.
Your quality concern is valid. I think the quality expectation for
LocalApicTimerDxe should be same, no matter it is in OvmfPkg or UefiCpuPkg.
I don't think the expectation is that the quality can be lower if it is in
OvmfPkg and it must be higher if it is in UefiCpuPkg.
All quality issues of LocalApicTimerDxe should be resolved, no matter where it
is finally located.
Thank you
Yao Jiewen
> -Original Message-
> From: Ni, Ray
> Sent: Monday, November 22, 2021 11:05 AM
> To: Xu, Min M ; devel@edk2.groups.io
> Cc: Yao, Jiewen ; Gerd Hoffmann
> ; Anthony Perard ; Julien
> Grall ; Dong, Eric
> Subject: RE: [PATCH V3 3/3] OvmfPkg: Move LocalApicTimerDxe to UefiCpuPkg
>
> Min,
> What's the reason of moving this driver to UefiCpuPkg?
>
> When the LocalApicTimerDxe is in OvmfPkg, it's clear that this driver is only
> used
> by OVMF/QEMU platform.
> Now since the patch moves the driver to UefiCpuPkg, it's possible that other
> platforms may choose this driver as the timer driver in DXE phase.
>
> So, we need to make sure the quality of this driver is good enough for a broad
> scope of platforms.
>
> 1. What's the issue when this driver still stays in OvmfPkg? If it's a must
> that this
> driver stays in UefiCpuPkg, please help to address following questions:
>
> 2. Can SourceLevelDebug (rely on Local APIC timer) work if this driver is
> chosen
> as DXE timer driver?
> 3. Can detailed comments be added for " @bug : This does not handle missed
> timer interrupts" in TimerInterruptHandler()?
> 4. Can detailed comments be added for " DisableInterrupts ();" in
> TimerInterruptHandler()?
> 5. In general what kinds of platforms are capable of using this driver as
> Timer
> driver?
>
> Thanks,
> Ray
>
> -Original Message-
> From: Xu, Min M
> Sent: Monday, November 8, 2021 2:08 PM
> To: devel@edk2.groups.io
> Cc: Xu, Min M ; Yao, Jiewen ;
> Gerd Hoffmann ; Anthony Perard
> ; Julien Grall ; Dong, Eric
> ; Ni, Ray
> Subject: [PATCH V3 3/3] OvmfPkg: Move LocalApicTimerDxe to UefiCpuPkg
>
> BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3711
>
> OvmfPkg.dec is removed from [Packages] because it doesn't depend
> on OvmfPkg. LocalApicTimerDxe is moved to UefiCpuPkg.
>
> Cc: Jiewen Yao
> Cc: Gerd Hoffmann
> Cc: Anthony Perard
> Cc: Julien Grall
> Cc: Eric Dong
> Cc: Ray Ni
> Signed-off-by: Min Xu
> ---
> OvmfPkg/AmdSev/AmdSevX64.dsc| 2 +-
> OvmfPkg/AmdSev/AmdSevX64.fdf| 2 +-
> OvmfPkg/Microvm/MicrovmX64.dsc | 2 +-
> OvmfPkg/Microvm/MicrovmX64.fdf | 2 +-
> OvmfPkg/OvmfPkgIa32.dsc | 2 +-
> OvmfPkg/OvmfPkgIa32.fdf | 2 +-
> OvmfPkg/OvmfPkgIa32X64.dsc | 2 +-
> OvmfPkg/OvmfPkgIa32X64.fdf | 2 +-
> OvmfPkg/OvmfPkgX64.dsc | 2 +-
> OvmfPkg/OvmfPkgX64.fdf | 2 +-
> OvmfPkg/OvmfXen.dsc | 2 +-
> OvmfPkg/OvmfXen.fdf | 2 +-
> .../LocalApicTimerDxe/LocalApicTimerDxe.c | 0
> .../LocalApicTimerDxe/LocalApicTimerDxe.h | 0
> .../LocalApicTimerDxe/LocalApicTimerDxe.inf | 6 --
> 15 files changed, 16 insertions(+), 14 deletions(-)
> rename {OvmfPkg => UefiCpuPkg}/LocalApicTimerDxe/LocalApicTimerDxe.c
> (100%)
> rename {OvmfPkg => UefiCpuPkg}/LocalApicTimerDxe/LocalApicTimerDxe.h
> (100%)
> rename {OvmfPkg => UefiCpuPkg}/LocalApicTimerDxe/LocalApicTimerDxe.inf
> (79%)
>
> diff --git a/OvmfPkg/AmdSev/AmdSevX64.dsc
> b/OvmfPkg/AmdSev/AmdSevX64.dsc
> index 88c51dfe8337..888fc24f1b58 100644
> --- a/OvmfPkg/AmdSev/AmdSevX64.dsc
> +++ b/OvmfPkg/AmdSev/AmdSevX64.dsc
> @@ -674,7 +674,7 @@
>MdeModulePkg/Universal/EbcDxe/EbcDxe.inf
>UefiCpuPkg/CpuIo2Dxe/CpuIo2Dxe.inf
>UefiCpuPkg/CpuDxe/CpuDxe.inf
> - OvmfPkg/LocalApicTimerDxe/LocalApicTimerDxe.inf
> + UefiCpuPkg/LocalApicTimerDxe/LocalApicTimerDxe.inf
>
> OvmfPkg/IncompatiblePciDeviceSupportDxe/IncompatiblePciDeviceSupport.inf
>OvmfPkg/PciHotPlugInitDxe/PciHotPlugInit.inf
>MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridgeDxe.inf {
> diff --git a/OvmfPkg/AmdSev/AmdSevX64.fdf
> b/OvmfPkg/AmdSev/AmdSevX64.fdf
> index 7489b04198fe..659810f96bec 100644
> --- a/OvmfPkg/AmdSev/AmdSevX64.fdf
> +++ b/OvmfPkg/AmdSev/AmdSevX64.fdf
> @@ -208,7 +208,7 @@ INF
> MdeModulePkg/Universal/SecurityStubDxe/SecurityStubDxe.inf
> INF MdeModulePkg/Universal/EbcDxe/EbcDxe.inf
> INF UefiCpuPkg/CpuIo2Dxe/CpuIo2Dxe.inf
> INF UefiCpuPkg/CpuDxe/CpuDxe.inf
> -INF OvmfPkg/LocalApicTimer
Re: [edk2-devel] [PATCH V3 3/3] OvmfPkg: Move LocalApicTimerDxe to UefiCpuPkg
Min,
What's the reason of moving this driver to UefiCpuPkg?
When the LocalApicTimerDxe is in OvmfPkg, it's clear that this driver is only
used by OVMF/QEMU platform.
Now since the patch moves the driver to UefiCpuPkg, it's possible that other
platforms may choose this driver as the timer driver in DXE phase.
So, we need to make sure the quality of this driver is good enough for a broad
scope of platforms.
1. What's the issue when this driver still stays in OvmfPkg? If it's a must
that this driver stays in UefiCpuPkg, please help to address following
questions:
2. Can SourceLevelDebug (rely on Local APIC timer) work if this driver is
chosen as DXE timer driver?
3. Can detailed comments be added for " @bug : This does not handle missed
timer interrupts" in TimerInterruptHandler()?
4. Can detailed comments be added for " DisableInterrupts ();" in
TimerInterruptHandler()?
5. In general what kinds of platforms are capable of using this driver as Timer
driver?
Thanks,
Ray
-Original Message-
From: Xu, Min M
Sent: Monday, November 8, 2021 2:08 PM
To: devel@edk2.groups.io
Cc: Xu, Min M ; Yao, Jiewen ; Gerd
Hoffmann ; Anthony Perard ;
Julien Grall ; Dong, Eric ; Ni, Ray
Subject: [PATCH V3 3/3] OvmfPkg: Move LocalApicTimerDxe to UefiCpuPkg
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3711
OvmfPkg.dec is removed from [Packages] because it doesn't depend
on OvmfPkg. LocalApicTimerDxe is moved to UefiCpuPkg.
Cc: Jiewen Yao
Cc: Gerd Hoffmann
Cc: Anthony Perard
Cc: Julien Grall
Cc: Eric Dong
Cc: Ray Ni
Signed-off-by: Min Xu
---
OvmfPkg/AmdSev/AmdSevX64.dsc| 2 +-
OvmfPkg/AmdSev/AmdSevX64.fdf| 2 +-
OvmfPkg/Microvm/MicrovmX64.dsc | 2 +-
OvmfPkg/Microvm/MicrovmX64.fdf | 2 +-
OvmfPkg/OvmfPkgIa32.dsc | 2 +-
OvmfPkg/OvmfPkgIa32.fdf | 2 +-
OvmfPkg/OvmfPkgIa32X64.dsc | 2 +-
OvmfPkg/OvmfPkgIa32X64.fdf | 2 +-
OvmfPkg/OvmfPkgX64.dsc | 2 +-
OvmfPkg/OvmfPkgX64.fdf | 2 +-
OvmfPkg/OvmfXen.dsc | 2 +-
OvmfPkg/OvmfXen.fdf | 2 +-
.../LocalApicTimerDxe/LocalApicTimerDxe.c | 0
.../LocalApicTimerDxe/LocalApicTimerDxe.h | 0
.../LocalApicTimerDxe/LocalApicTimerDxe.inf | 6 --
15 files changed, 16 insertions(+), 14 deletions(-)
rename {OvmfPkg => UefiCpuPkg}/LocalApicTimerDxe/LocalApicTimerDxe.c (100%)
rename {OvmfPkg => UefiCpuPkg}/LocalApicTimerDxe/LocalApicTimerDxe.h (100%)
rename {OvmfPkg => UefiCpuPkg}/LocalApicTimerDxe/LocalApicTimerDxe.inf (79%)
diff --git a/OvmfPkg/AmdSev/AmdSevX64.dsc b/OvmfPkg/AmdSev/AmdSevX64.dsc
index 88c51dfe8337..888fc24f1b58 100644
--- a/OvmfPkg/AmdSev/AmdSevX64.dsc
+++ b/OvmfPkg/AmdSev/AmdSevX64.dsc
@@ -674,7 +674,7 @@
MdeModulePkg/Universal/EbcDxe/EbcDxe.inf
UefiCpuPkg/CpuIo2Dxe/CpuIo2Dxe.inf
UefiCpuPkg/CpuDxe/CpuDxe.inf
- OvmfPkg/LocalApicTimerDxe/LocalApicTimerDxe.inf
+ UefiCpuPkg/LocalApicTimerDxe/LocalApicTimerDxe.inf
OvmfPkg/IncompatiblePciDeviceSupportDxe/IncompatiblePciDeviceSupport.inf
OvmfPkg/PciHotPlugInitDxe/PciHotPlugInit.inf
MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridgeDxe.inf {
diff --git a/OvmfPkg/AmdSev/AmdSevX64.fdf b/OvmfPkg/AmdSev/AmdSevX64.fdf
index 7489b04198fe..659810f96bec 100644
--- a/OvmfPkg/AmdSev/AmdSevX64.fdf
+++ b/OvmfPkg/AmdSev/AmdSevX64.fdf
@@ -208,7 +208,7 @@ INF
MdeModulePkg/Universal/SecurityStubDxe/SecurityStubDxe.inf
INF MdeModulePkg/Universal/EbcDxe/EbcDxe.inf
INF UefiCpuPkg/CpuIo2Dxe/CpuIo2Dxe.inf
INF UefiCpuPkg/CpuDxe/CpuDxe.inf
-INF OvmfPkg/LocalApicTimerDxe/LocalApicTimerDxe.inf
+INF UefiCpuPkg/LocalApicTimerDxe/LocalApicTimerDxe.inf
INF OvmfPkg/IncompatiblePciDeviceSupportDxe/IncompatiblePciDeviceSupport.inf
INF OvmfPkg/PciHotPlugInitDxe/PciHotPlugInit.inf
INF MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridgeDxe.inf
diff --git a/OvmfPkg/Microvm/MicrovmX64.dsc b/OvmfPkg/Microvm/MicrovmX64.dsc
index 1a0e848f8356..fcb8b571a041 100644
--- a/OvmfPkg/Microvm/MicrovmX64.dsc
+++ b/OvmfPkg/Microvm/MicrovmX64.dsc
@@ -656,7 +656,7 @@
MdeModulePkg/Universal/SecurityStubDxe/SecurityStubDxe.inf
MdeModulePkg/Universal/EbcDxe/EbcDxe.inf
- OvmfPkg/LocalApicTimerDxe/LocalApicTimerDxe.inf
+ UefiCpuPkg/LocalApicTimerDxe/LocalApicTimerDxe.inf
UefiCpuPkg/CpuIo2Dxe/CpuIo2Dxe.inf
UefiCpuPkg/CpuDxe/CpuDxe.inf
OvmfPkg/IncompatiblePciDeviceSupportDxe/IncompatiblePciDeviceSupport.inf
diff --git a/OvmfPkg/Microvm/MicrovmX64.fdf b/OvmfPkg/Microvm/MicrovmX64.fdf
index ac9efba26811..d02e88e2a48e 100644
--- a/OvmfPkg/Microvm/MicrovmX64.fdf
+++ b/OvmfPkg/Microvm/MicrovmX64.fdf
@@ -215,7 +215,7 @@ INF MdeModulePkg/Univer
Re: [edk2-devel] [PATCH V3 3/3] OvmfPkg: Move LocalApicTimerDxe to UefiCpuPkg
On Mon, Nov 08, 2021 at 02:08:00PM +0800, Min Xu wrote: > BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3711 > > OvmfPkg.dec is removed from [Packages] because it doesn't depend > on OvmfPkg. LocalApicTimerDxe is moved to UefiCpuPkg. > > Cc: Jiewen Yao > Cc: Gerd Hoffmann > Cc: Anthony Perard > Cc: Julien Grall > Cc: Eric Dong > Cc: Ray Ni > Signed-off-by: Min Xu Reviewed-by: Anthony PERARD Thanks, -- Anthony PERARD -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#83652): https://edk2.groups.io/g/devel/message/83652 Mute This Topic: https://groups.io/mt/86900367/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
