Re: [Minios-devel] [UNIKRAFT PATCH 2/2] plat/xen: CPU definition for Arm32

[Simon Kuenzer <simon.kuenzer@xxxxxxxxx>]

On 12.02.19, 19:24, "Sharan Santhanam" <Sharan.Santhanam@xxxxxxxxx> wrote:

    Hello Simon,
    
    Please find the comment inline.
    
    Thanks & Regards
    Sharan
    
    On 2/11/19 3:53 PM, Simon Kuenzer wrote:
    > Introduce minimal CPU definitons to enable compiling for Arm32.
    > This commits also removes x86 specific CPU functions from the
    > Arm32 build unit.
    > 
    > Signed-off-by: Simon Kuenzer <simon.kuenzer@xxxxxxxxx>
    > ---
    >   plat/common/include/arm/arm/cpu.h | 12 +++++++++++-
    >   plat/xen/Makefile.uk              |  4 ++--
    >   2 files changed, 13 insertions(+), 3 deletions(-)
    > 
    > diff --git a/plat/common/include/arm/arm/cpu.h 
b/plat/common/include/arm/arm/cpu.h
    > index 697a20a1..bc4d413c 100644
    > --- a/plat/common/include/arm/arm/cpu.h
    > +++ b/plat/common/include/arm/arm/cpu.h
    > @@ -1,8 +1,9 @@
    >   /* SPDX-License-Identifier: BSD-3-Clause */
    >   /*
    >    * Authors: Simon Kuenzer <simon.kuenzer@xxxxxxxxx>
    > + * Authors: Wei Chen <wei.chen@xxxxxxx>
    >    *
    > - *
    > + * Copyright (c) 2018, Arm Ltd. All rights reserved.
    >    * Copyright (c) 2019, NEC Laboratories Europe GmbH, NEC Corporation.
    >    *                     All rights reserved.
    >    *
    > @@ -37,3 +38,12 @@
    >   static inline void _init_cpufeatures(void)
    >   {
    >   }
    > +
    > +/*
    > + * Halts the CPU until the next external interrupt is fired. For Arm,
    > + * we can use WFI to implement this feature.
    > + */
    
    Aren't we duplicating the function here.
    We have a halt function defined in
    plat/common/arm/cpu_native.c
    
    Any specific reason we are not using it?

It is because cpu_native is defining much more stuff we aren't support right 
now for Arm32. However, we could guard it with macros instead. Maybe that is a 
better solution. I will send a v2.

    > +static inline void halt(void)
    > +{
    > + __asm__ __volatile__("wfi");
    > +}
    > diff --git a/plat/xen/Makefile.uk b/plat/xen/Makefile.uk
    > index 7a3fcc93..5bde25f3 100644
    > --- a/plat/xen/Makefile.uk
    > +++ b/plat/xen/Makefile.uk
    > @@ -49,9 +49,9 @@ LIBXENPLAT_SRCS-$(CONFIG_ARCH_X86_64) += 
$(LIBXENPLAT_BASE)/x86/arch_time.c
    >   ifneq ($(XEN_HVMLITE),y)
    >   LIBXENPLAT_ASFLAGS-y           += -DCONFIG_PARAVIRT
    >   LIBXENPLAT_CFLAGS-y            += -DCONFIG_PARAVIRT
    > -LIBXENPLAT_SRCS-y              += $(LIBXENPLAT_BASE)/x86/cpu_pv.c
    > +LIBXENPLAT_SRCS-$(CONFIG_ARCH_X86_64) += $(LIBXENPLAT_BASE)/x86/cpu_pv.c
    >   else
    > -LIBXENPLAT_SRCS-y              += $(UK_PLAT_COMMON_BASE)/x86/cpu_native.c
    > +LIBXENPLAT_SRCS-$(CONFIG_ARCH_X86_64) += 
$(UK_PLAT_COMMON_BASE)/x86/cpu_native.c
    >   endif
    >   
    >   LIBXENPLAT_SRCS-$(CONFIG_ARCH_ARM_32) += $(LIBXENPLAT_BASE)/arm/setup.c
    > 
    

_______________________________________________
Minios-devel mailing list
Minios-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/minios-devel