Re: [Qemu-devel] [PATCH v6 5/6] acpi: Add IPMI table entries

[Corey Minyard]

On 05/24/2016 02:49 AM, Igor Mammedov wrote:
> On Mon, 23 May 2016 12:40:16 -0500
> address@hidden wrote:
>
> > From: Corey Minyard <address@hidden>
> >
> > Use the new ACPI table construction tools to create an ACPI
> > entry for IPMI.  This adds a function called from build_dsdt
> > to add an DSDT entry for IPMI if IPMI is compiled in and has
> > registered firmware.  It also adds a dummy function if IPMI
> > is not compiled in.
> >
> > This conforms to section "C3-2 Locating IPMI System Interfaces in
> > ACPI Name Space" in the IPMI 2.0 specification.
> >
> > Signed-off-by: Corey Minyard <address@hidden>
> > ---
> >   hw/acpi/Makefile.objs  |   2 +
> >   hw/acpi/ipmi.c         | 105 +++++++++++++++++++++++++++++++++++++++++++++++++
> >   hw/i386/acpi-build.c   |  24 +++++++++--
> >   hw/stubs/Makefile.objs |   1 +
> >   hw/stubs/acpi_ipmi.c   |  14 +++++++
> >   include/hw/acpi/ipmi.h |  22 +++++++++++
> >   6 files changed, 165 insertions(+), 3 deletions(-)
> >   create mode 100644 hw/acpi/ipmi.c
> >   create mode 100644 hw/stubs/acpi_ipmi.c
> >   create mode 100644 include/hw/acpi/ipmi.h
> >
> > diff --git a/hw/acpi/Makefile.objs b/hw/acpi/Makefile.objs
> > index faee86c..95824e8 100644
> > --- a/hw/acpi/Makefile.objs
> > +++ b/hw/acpi/Makefile.objs
> > @@ -6,3 +6,5 @@ obj-$(CONFIG_ACPI_NVDIMM) += nvdimm.o
> >   common-obj-$(CONFIG_ACPI) += acpi_interface.o
> >   common-obj-$(CONFIG_ACPI) += bios-linker-loader.o
> >   common-obj-$(CONFIG_ACPI) += aml-build.o
> > +common-obj-$(call land,$(CONFIG_ACPI),$(CONFIG_IPMI)) += ipmi.o
> > +
> > diff --git a/hw/acpi/ipmi.c b/hw/acpi/ipmi.c
> > new file mode 100644
> > index 0000000..201f824
> > --- /dev/null
> > +++ b/hw/acpi/ipmi.c
> > @@ -0,0 +1,105 @@
> > +/*
> > + * IPMI ACPI firmware handling
> > + *
> > + * Copyright (c) 2015 Corey Minyard, MontaVista Software, LLC
> > + *
> > + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> > + * See the COPYING file in the top-level directory.
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +#include "hw/ipmi/ipmi.h"
> > +#include "hw/acpi/aml-build.h"
> > +#include "hw/acpi/acpi.h"
> > +#include "hw/acpi/ipmi.h"
> > +
> > +static Aml *aml_ipmi_crs(IPMIFwInfo *info)
> > +{
> > +    Aml *crs = aml_resource_template();
> > +    uint8_t regspacing = info->register_spacing;
> nit about naming,
> why not s/regspacing|register_spacing/reg_alignment/

"Register spacing" comes from the SMBIOS definition in the IPMI spec.  
Since I did SMBIOS first, it won.

There's no reason to have a local for this now (I think there was at 
some point).

.
.
.

> > +
> > +        if (!obj) {
> > +            continue;
> > +        }
> > +
> > +        ii = IPMI_INTERFACE(obj);
> > +        iic = IPMI_INTERFACE_GET_CLASS(obj);
> > +        memset(&info, 0, sizeof(info));
> why not to put memset() inside iic->get_fwinfo(),
> that way every caller won't have to do it  (SMBIOS call site).

I debated on that, but there are actually fewer call sites than
implementers here.  Well, they are equal now, but with SMBus
there will be more implementers.

> > +        iic->get_fwinfo(ii, &info);
> > +        aml_append(scope, aml_ipmi_device(&info));
> > +    }
> > +}
> > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > index 279f0d7..bf9253d 100644
> > --- a/hw/i386/acpi-build.c
> > +++ b/hw/i386/acpi-build.c
> > @@ -59,6 +59,8 @@
> >   #include "qapi/qmp/qint.h"
> >   #include "qom/qom-qobject.h"
> >   
> > +#include "hw/acpi/ipmi.h"
> > +
> >   /* These are used to size the ACPI tables for -M pc-i440fx-1.7 and
> >    * -M pc-i440fx-2.0.  Even if the actual amount of AML generated grows
> >    * a little bit, there should be plenty of free space since the DSDT
> > @@ -1445,7 +1447,21 @@ static Aml *build_com_device_aml(uint8_t uid)
> >       return dev;
> >   }
> >   
> > -static void build_isa_devices_aml(Aml *table)
> > +static void build_isa_ipmi_aml(Aml *scope)
> > +{
> > +    bool ambiguous;
> > +    Object *obj = object_resolve_path_type("", TYPE_ISA_BUS, &ambiguous);
> > +
> > +    if (ambiguous) {
> > +        error_report("Multiple ISA busses, unable to define IPMI ACPI data");
> > +    } else if (!obj) {
> > +        error_report("No ISA bus, unable to define IPMI ACPI data");
> > +    } else {
> > +        build_acpi_ipmi_devices(scope, BUS(obj));
> > +    }
> > +}
> I'd fold this function into build_acpi_ipmi_devices() if there aren't any plans
> for IPMI devices being present on another bus.

Ok, it looked a little neater this way to me, but that's fine.

> > +
> > +static void build_isa_devices_aml(Aml *table, PCMachineState *pcms)
> why is pcms is added here, it doesn't seem to be used?

I forgot to remove it when I removed the isa_bus from PCMachineState.

Thanks,

-corey