Re: [PATCH v4 2/3] acpi: tpm: Add missing device identification objects

[Igor Mammedov <imammedo@redhat.com>]

On Tue, 4 Jan 2022 09:48:32 -0500
Stefan Berger <stefanb@linux.ibm.com> wrote:

> On 1/4/22 04:55, Igor Mammedov wrote:
> > On Wed, 22 Dec 2021 21:23:09 -0500
> > Stefan Berger <stefanb@linux.ibm.com> wrote:
> >  
> >> Add missing device identification objects _STR and _UID. They will appear  
> > why, does it break anything or it's just cosmetic?  
> 
> I don't know about whether any software needs these entries but it's 
> driven by this:
> 
> https://gitlab.com/qemu-project/qemu/-/issues/708
> 
> 
> >  
> >> as files 'description' and 'uid' under Linux sysfs.
> >>
> >> Cc: Shannon Zhao <shannon.zhaosl@gmail.com>
> >> Cc: Michael S. Tsirkin <mst@redhat.com>
> >> Cc: Igor Mammedov <imammedo@redhat.com>
> >> Cc: Ani Sinha <ani@anisinha.ca>
> >> Fixes: https://gitlab.com/qemu-project/qemu/-/issues/708
> >> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> >> Message-id: 20211110133559.3370990-3-stefanb@linux.ibm.com
> >> ---
> >>   hw/arm/virt-acpi-build.c | 1 +
> >>   hw/i386/acpi-build.c     | 8 ++++++++
> >>   2 files changed, 9 insertions(+)
> >>
> >> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> >> index d0f4867fdf..f2514ce77c 100644
> >> --- a/hw/arm/virt-acpi-build.c
> >> +++ b/hw/arm/virt-acpi-build.c
> >> @@ -229,6 +229,7 @@ static void acpi_dsdt_add_tpm(Aml *scope, VirtMachineState *vms)
> >>   
> >>       Aml *dev = aml_device("TPM0");
> >>       aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
> >> +    aml_append(dev, aml_name_decl("_STR", aml_string("TPM 2.0 Device")));
> >>       aml_append(dev, aml_name_decl("_UID", aml_int(0)));
> >>   
> >>       Aml *crs = aml_resource_template();
> >> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> >> index 8383b83ee3..2fb70847cb 100644
> >> --- a/hw/i386/acpi-build.c
> >> +++ b/hw/i386/acpi-build.c
> >> @@ -1812,11 +1812,15 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >>                       dev = aml_device("TPM");
> >>                       aml_append(dev, aml_name_decl("_HID",
> >>                                                     aml_string("MSFT0101")));
> >> +                    aml_append(dev,
> >> +                               aml_name_decl("_STR",
> >> +                                             aml_string("TPM 2.0 Device")));
> >>                   } else {
> >>                       dev = aml_device("ISA.TPM");
> >>                       aml_append(dev, aml_name_decl("_HID",
> >>                                                     aml_eisaid("PNP0C31")));
> >>                   }
> >> +                aml_append(dev, aml_name_decl("_UID", aml_int(1)));  
> > why it's 1, and not 0 as in virt-arm?  
> 
> Marc-Andre and I looked at machines with hardware TPMs and that's what 
> we found there as well, a '1'.

perhaps mention that in commit message

> 
> 
> >  
> >>   
> >>                   aml_append(dev, aml_name_decl("_STA", aml_int(0xF)));
> >>                   crs = aml_resource_template();
> >> @@ -1844,6 +1848,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >>       if (TPM_IS_CRB(tpm)) {
> >>           dev = aml_device("TPM");
> >>           aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
> >> +        aml_append(dev, aml_name_decl("_STR",
> >> +                                      aml_string("TPM 2.0 Device")));
> >>           crs = aml_resource_template();
> >>           aml_append(crs, aml_memory32_fixed(TPM_CRB_ADDR_BASE,
> >>                                              TPM_CRB_ADDR_SIZE, AML_READ_WRITE));
> >> @@ -1851,6 +1857,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
> >>   
> >>           aml_append(dev, aml_name_decl("_STA", aml_int(0xf)));
> >>  
> > no necessary ^^^ empty line  
> fixed
> >  
> >> +        aml_append(dev, aml_name_decl("_UID", aml_int(1)));
> >> +
> >>           tpm_build_ppi_acpi(tpm, dev);
> >>   
> >>           aml_append(sb_scope, dev);  
>