Hi JP, Is there a reason switch BSP is being used. That is not a common operation and is typically used if the current BSP is not stable or there is a good reason to switch the BSP for OS boot.
The MP Services can be used to execute a C function on APs to execute MSR related instructions. Mike > -----Original Message----- > From: Jayaprakash, N <n.jayaprak...@intel.com> > Sent: Sunday, April 14, 2024 10:33 PM > To: devel@edk2.groups.io; Jayaprakash, N <n.jayaprak...@intel.com> > Cc: Rebecca Cran <rebe...@bsdio.com>; Kinney, Michael D > <michael.d.kin...@intel.com> > Subject: RE: [edk2-devel] [edk2-libc Patch 1/1] edk2-libc:add rdmsr_ex > & wrmsr_ex functions to read/write cpu specific msrs > > + Rebecca and Mike, > > Would you be able to review this PR? > > Regards, > JP > > -----Original Message----- > From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of > Jayaprakash, N > Sent: Wednesday, April 10, 2024 11:49 AM > To: devel@edk2.groups.io > Cc: Jayaprakash, N <n.jayaprak...@intel.com>; Rebecca Cran > <rebe...@bsdio.com>; Kinney, Michael D <michael.d.kin...@intel.com> > Subject: [edk2-devel] [edk2-libc Patch 1/1] edk2-libc:add rdmsr_ex & > wrmsr_ex functions to read/write cpu specific msrs > > REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4746 > > The rdmsr_ex and wrmsr_ex are extension APIs to the rdmsr and wrmsr > APIs supported in edk2 module. These extension APIs makes it possible > to read / write MSRs from specific processors and fills an existing > gap in this area. > > Cc: Rebecca Cran <rebe...@bsdio.com> > Cc: Michael D Kinney <michael.d.kin...@intel.com> > Cc: Jayaprakash N <n.jayaprak...@intel.com> > Signed-off-by: Jayaprakash N <n.jayaprak...@intel.com> > --- > .../PyMod-3.6.8/Modules/edk2module.c | 159 > +++++++++++++++++- > .../Python/Python-3.6.8/Python368.inf | 3 + > 2 files changed, 158 insertions(+), 4 deletions(-) > > diff --git a/AppPkg/Applications/Python/Python-3.6.8/PyMod- > 3.6.8/Modules/edk2module.c b/AppPkg/Applications/Python/Python- > 3.6.8/PyMod-3.6.8/Modules/edk2module.c > index d6af8da..f1b13a6 100644 > --- a/AppPkg/Applications/Python/Python-3.6.8/PyMod- > 3.6.8/Modules/edk2module.c > +++ b/AppPkg/Applications/Python/Python-3.6.8/PyMod- > 3.6.8/Modules/edk2mo > +++ dule.c > @@ -3,7 +3,7 @@ > Derived from posixmodule.c in Python 2.7.2. > > Copyright (c) 2015, Daryl McDaniel. All rights reserved.<BR> > - Copyright (c) 2011 - 2023, Intel Corporation. All rights > reserved.<BR> > + Copyright (c) 2011 - 2024, Intel Corporation. All rights > + reserved.<BR> > This program and the accompanying materials are licensed and made > available under > the terms and conditions of the BSD License that accompanies this > distribution. > The full text of the license may be found at @@ -22,16 +22,23 @@ > #include <wchar.h> #include <sys/syslimits.h> #include <Uefi.h> > +#include <Pi/PiDxeCis.h> // Needed for the definition of > EFI_AP_PROCEDURE > #include <Library/UefiLib.h> > #include <Library/PciLib.h> > #include <Library/IoLib.h> > #include <Library/UefiRuntimeServicesTableLib.h> > +#include <Library/UefiBootServicesTableLib.h> > +#include <Protocol/MpService.h> > > #ifdef __cplusplus > extern "C" { > #endif > > PyTypeObject EfiGuidType; > +EFI_MP_SERVICES_PROTOCOL *gpMpService = NULL; > +UINTN gBSPProcessorNumber = 0; > +UINTN gNumberOfProcessors = 0; > +UINTN gNumberOfEnabledProcessors = 0; > > extern void _swsmi( unsigned int smi_code_data, unsigned int > rax_value, unsigned int rbx_value, unsigned int rcx_value, unsigned > int rdx_value, unsigned int rsi_value, unsigned int rdi_value ); // - > - Support routines @@ -169,6 +176,35 @@ PyDoc_STRVAR(edk2__doc__, > /* dummy version. _PyVerify_fd() is already defined in fileobject.h > */ #define _PyVerify_fd_dup2(A, B) (1) > > +static EFI_STATUS > +MpServicesWhoAmI ( > + IN EFI_MP_SERVICES_PROTOCOL *pMpService, > + OUT UINTN *pProcessorNumber > + ) > +{ > + return pMpService->WhoAmI (pMpService, pProcessorNumber); } > + > +static EFI_STATUS > +MpServicesGetNumberOfProcessors ( > + IN EFI_MP_SERVICES_PROTOCOL *pMpService, > + OUT UINTN *pNumberOfProcessors, > + OUT UINTN *pNumberOfEnabledProcessors > + > + ) > +{ > + return pMpService->GetNumberOfProcessors (pMpService, > +pNumberOfProcessors, pNumberOfEnabledProcessors); } > + > +static EFI_STATUS > +MpServicesSwitchBSP ( > + IN EFI_MP_SERVICES_PROTOCOL *pMpService, > + IN UINTN ProcessorNumber > + ) > +{ > + return pMpService->SwitchBSP(pMpService, ProcessorNumber, TRUE); } > + > #ifndef UEFI_C_SOURCE > /* Return a dictionary corresponding to the POSIX environment table > */ extern char **environ; @@ -3865,6 +3901,56 @@ edk2_rdmsr(PyObject > *self, PyObject *args) > return Py_BuildValue("(II)", (unsigned long)veax, (unsigned > long)vedx); } > > +PyDoc_STRVAR(efi_rdmsr_ex__doc__, > +"rdmsr_ex(cpu, msr) -> (lower_32bits, higher_32bits)\n\ \n\ Read the > +given msr by switching to cpu and return the data as tuple.\n\ \n\ > +Parameters:\n\ > + cpu - The cpu number in hex or int format\n\ > + msr - The msr in hex or int format\n\ \n\ Return Value:\n\ > + a tuple with lower and higher 32 bit values read from the msr\n\ > +"); > + > +static PyObject * > +edk2_rdmsr_ex(PyObject *self, PyObject *args) { > + unsigned int cpu, vecx, veax, vedx; > + unsigned int bsp_switched = 0; > + EFI_STATUS status = 0; > + UINT64 data = 0; > + > + if (!PyArg_ParseTuple(args, "II", &cpu, &vecx)) > + return NULL; > + > + Py_BEGIN_ALLOW_THREADS > + if (cpu != gBSPProcessorNumber && cpu < gNumberOfProcessors) { > + //switch the BSP to the cpu > + status = MpServicesSwitchBSP(gpMpService, cpu); > + if (!EFI_ERROR(status)) > + { > + bsp_switched = 1; > + } > + } > + > + data = AsmReadMsr64(vecx); > + > + if (bsp_switched) > + { > + // switch BSP to the saved BSP processor > + MpServicesSwitchBSP(gpMpService, gBSPProcessorNumber); > + // update the saved BSP processor > + MpServicesWhoAmI(gpMpService, &gBSPProcessorNumber); > + } > + Py_END_ALLOW_THREADS > + veax = (UINT32)data; > + vedx = (UINT64)data >> 32; > + return Py_BuildValue("(II)", (unsigned long)veax, (unsigned > +long)vedx); } > + > PyDoc_STRVAR(efi_wrmsr__doc__, > "wrmsr(msr, lower_32bits, higher_32bits) -> None\n\ \n\ @@ -3889,6 > +3975,58 @@ edk2_wrmsr(PyObject *self, PyObject *args) > data = vedx << 32 | veax; > Py_BEGIN_ALLOW_THREADS > AsmWriteMsr64(vecx, data); > + Py_END_ALLOW_THREADS > + Py_INCREF(Py_None); > + return Py_None; > +} > + > +PyDoc_STRVAR(efi_wrmsr_ex__doc__, > +"wrmsr_ex(cpu, msr, lower_32bits, higher_32bits) -> None\n\ \n\ > Writes > +higher_32bits:lower_32bits to the given msr.\n\ \n\ Parameters:\n\ > + cpu - The cpu number in hex or int format\n\ > + msr - The msr in hex or int format\n\ > + lower_32bits - The lower 32 bit data for the msr\n\ > + higher_32bits - The higher 32 bit data for the msr\n\ \n\ Return > +Value:\n\ > + None\n\ > +"); > + > +static PyObject * > +edk2_wrmsr_ex(PyObject *self, PyObject *args) { > + unsigned int cpu, msr, veax, vedx; > + unsigned int bsp_switched = 0; > + EFI_STATUS status = 0; > + UINT64 data = 0; > + > + if (!PyArg_ParseTuple(args, "IIII", &cpu, &msr, &veax, &vedx)) > + return NULL; > + data = (((UINT64)vedx) << 32) | veax; > + > + Py_BEGIN_ALLOW_THREADS > + if (cpu != gBSPProcessorNumber && cpu < gNumberOfProcessors) { > + //switch the BSP to the cpu > + status = MpServicesSwitchBSP(gpMpService, cpu); > + if (!EFI_ERROR(status)) > + { > + bsp_switched = 1; > + } > + } > + // write to MSR > + AsmWriteMsr64(msr, data); > + > + if (bsp_switched) > + { > + // switch BSP to the saved BSP processor > + MpServicesSwitchBSP(gpMpService, gBSPProcessorNumber); > + // update the saved BSP processor > + MpServicesWhoAmI(gpMpService, &gBSPProcessorNumber); } > Py_END_ALLOW_THREADS > Py_INCREF(Py_None); > return Py_None; > @@ -4576,7 +4714,9 @@ static PyMethodDef edk2_methods[] = { #endif > {"abort", edk2_abort, METH_NOARGS, > edk2_abort__doc__}, > {"rdmsr", edk2_rdmsr, METH_VARARGS, > efi_rdmsr__doc__}, > + {"rdmsr_ex", edk2_rdmsr_ex, METH_VARARGS, > efi_rdmsr_ex__doc__}, > {"wrmsr", edk2_wrmsr, METH_VARARGS, > efi_wrmsr__doc__}, > + {"wrmsr_ex", edk2_wrmsr_ex, METH_VARARGS, > efi_wrmsr_ex__doc__}, > {"readpci", edk2_readpci, METH_VARARGS, > efi_readpci__doc__}, > {"writepci", edk2_writepci, METH_VARARGS, > efi_writepci__doc__}, > {"readmem", posix_readmem, > METH_VARARGS, efi_readmem__doc__}, > @@ -4813,13 +4953,24 @@ static struct PyModuleDef edk2module = { > PyMODINIT_FUNC > PyEdk2__Init(void) > { > - PyObject *m; > + PyObject *m; > + EFI_STATUS Status = 0; > > #ifndef UEFI_C_SOURCE > PyObject *v; > #endif > + Status = gBS->LocateProtocol(&gEfiMpServiceProtocolGuid, NULL, > &gpMpService); > + if (EFI_ERROR(Status)) > + { > + printf("Unable to locate the Protocol MpServices protocol: > %r\n", Status); > + return NULL; > + } > + // Get the current BSP processor number > + MpServicesWhoAmI(gpMpService, &gBSPProcessorNumber); > + // Get the number of processors > + MpServicesGetNumberOfProcessors(gpMpService, > &gNumberOfProcessors, > + &gNumberOfEnabledProcessors); > > - m = PyModule_Create(&edk2module); > + m = PyModule_Create(&edk2module); > if (m == NULL) > return m; > > @@ -4870,7 +5021,7 @@ PyEdk2__Init(void) > //PyModule_AddObject(m, "statvfs_result", > // (PyObject*) &StatVFSResultType); > initialized = 1; > - return m; > + return m; > > } > > diff --git a/AppPkg/Applications/Python/Python-3.6.8/Python368.inf > b/AppPkg/Applications/Python/Python-3.6.8/Python368.inf > index 8b7f677..eca98b5 100644 > --- a/AppPkg/Applications/Python/Python-3.6.8/Python368.inf > +++ b/AppPkg/Applications/Python/Python-3.6.8/Python368.inf > @@ -46,6 +46,9 @@ > #BsdSocketLib > #EfiSocketLib > > +[Protocols] > + gEfiMpServiceProtocolGuid ## CONSUMES > + > [FixedPcd] > gEfiMdePkgTokenSpaceGuid.PcdDebugPropertyMask|0x0F > gEfiMdePkgTokenSpaceGuid.PcdDebugPrintErrorLevel|0x80000040 > -- > 2.40.0.windows.1 > > > > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. 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