Re: [Qemu-devel] [PATCH 1/2] acpi: tpm: Fix TPM ACPI description (BZ 1281413)

[Igor Mammedov]

On Mon, 4 Apr 2016 06:17:38 -0400
Stefan Berger <address@hidden> wrote:

> On 04/04/2016 05:04 AM, Michael S. Tsirkin wrote:
> > On Sun, Apr 03, 2016 at 09:37:55PM -0400, Stefan Berger wrote:
> >> This patch addresses BZ 1281413.
> >>
> >> https://bugzilla.redhat.com/show_bug.cgi?id=1281413
> >>
> >> Fix the APCI description to make it work on operating systems that
> >> are more strict about the contents of the TPM's ACPI description
> >> than Linux is. The ACPI description was broken in commit 9e472263.
> >>
> >> We roll back the ACPI description to where it was in QEMU 2.3.1 and
> >> deactivate the interrupt, modify the scope to \_SB, and change the
> >> name of the device back to 'TPM' from 'ISA.TPM'. Here's the ACPI
> >> description from QEMU 2.3.1:
> >>
> >>      Scope(\_SB) {
> >>          /* TPM with emulated TPM TIS interface */
> >>          Device (TPM) {
> >>              Name (_HID, EisaID ("PNP0C31"))
> >>              Name (_CRS, ResourceTemplate ()
> >>              {
> >>                  Memory32Fixed (ReadWrite, TPM_TIS_ADDR_BASE,
> >> TPM_TIS_ADDR_SIZE) // older Linux tpm_tis drivers do not work with
> >> IRQ //IRQNoFlags () {TPM_TIS_IRQ}
> >>              })
> >>              Method (_STA, 0, NotSerialized) {
> >>                  Return (0x0F)
> >>              }
> >>          }
> >>      }
> >>
> >> Signed-off-by: Stefan Berger <address@hidden>
> > Can we instead use Igor's patch
> >      pc: acpi: tpm: add missing MMIO resource to PCI0._CRS
> > and only drop the irq_no_flags value?
> 
> Igor's patch adds this here:
> 
> +
> +    if (misc->tpm_version != TPM_VERSION_UNSPEC) {
> +        aml_append(crs, aml_memory32_fixed(TPM_TIS_ADDR_BASE,
> +                   TPM_TIS_ADDR_SIZE, AML_READ_WRITE));
> +    }
> 
> 
> Now we that memory description there twice? I am not sure whether
> this is necessary, but you are the APCI experts.
Since TPM_TIS_ADDR_BASE is outside of PCI window of PCI0, we need to
add it explicitly to PCI0._CRS.
Moving out of scope is plainly wrong and works just by accident.

Granted that Michael is fine with hiding IRQ and provided
that you'll fix IRQ handling later, I won't object commenting
IRQ entry for 2.6.

> 
> 
> 
> >
> >
> >> ---
> >>   hw/i386/acpi-build.c | 26 ++++++++++++--------------
> >>   1 file changed, 12 insertions(+), 14 deletions(-)
> >>
> >> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> >> index 35180ef..e11c721 100644
> >> --- a/hw/i386/acpi-build.c
> >> +++ b/hw/i386/acpi-build.c
> >> @@ -2335,22 +2335,20 @@ build_dsdt(GArray *table_data, GArray
> >> *linker, Aml *scope = aml_scope("PCI0");
> >>                   /* Scan all PCI buses. Generate tables to
> >> support hotplug. */ build_append_pci_bus_devices(scope, bus,
> >> pm->pcihp_bridge_en); -
> >> -                if (misc->tpm_version != TPM_VERSION_UNSPEC) {
> >> -                    dev = aml_device("ISA.TPM");
> >> -                    aml_append(dev, aml_name_decl("_HID",
> >> aml_eisaid("PNP0C31")));
> >> -                    aml_append(dev, aml_name_decl("_STA",
> >> aml_int(0xF)));
> >> -                    crs = aml_resource_template();
> >> -                    aml_append(crs,
> >> aml_memory32_fixed(TPM_TIS_ADDR_BASE,
> >> -                               TPM_TIS_ADDR_SIZE,
> >> AML_READ_WRITE));
> >> -                    aml_append(crs,
> >> aml_irq_no_flags(TPM_TIS_IRQ));
> >> -                    aml_append(dev, aml_name_decl("_CRS", crs));
> >> -                    aml_append(scope, dev);
> >> -                }
> >> -
> >> -                aml_append(sb_scope, scope);
> >>               }
> >>           }
> >> +
> >> +        if (misc->tpm_version != TPM_VERSION_UNSPEC) {
> >> +            dev = aml_device("TPM");
> >> +            aml_append(dev, aml_name_decl("_HID",
> >> aml_eisaid("PNP0C31")));
> >> +            aml_append(dev, aml_name_decl("_STA", aml_int(0xF)));
> >> +            crs = aml_resource_template();
> >> +            aml_append(crs, aml_memory32_fixed(TPM_TIS_ADDR_BASE,
> >> +                       TPM_TIS_ADDR_SIZE, AML_READ_WRITE));
> >> +            //aml_append(crs, aml_irq_no_flags(TPM_TIS_IRQ));
> >> +            aml_append(dev, aml_name_decl("_CRS", crs));
> >> +            aml_append(sb_scope, dev);
> >> +        }
> >>           aml_append(dsdt, sb_scope);
> >>       }
> >>   
> >> -- 
> >> 2.5.5
>