On Thu, 27 Jun 2024 at 10:08, Borislav Petkov <bp@xxxxxxxxx> wrote:
>
> On Mon, May 06, 2024 at 05:47:20PM +0000, John Allen wrote:
> > Platform Runtime Mechanism (PRM) handlers can be invoked from either the
> > AML interpreter or directly by an OS driver. Implement the direct call
> > method.
> >
> > Export the symbol as this will be used by modules such as the AMD
> > Address Translation Library and likely others in the future.
> >
> > Signed-off-by: John Allen <john.allen@xxxxxxx>
> > Reviewed-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
> > ---
> > v2:
> > - Align statements setting fields in context buffer on '='
> > ---
> > drivers/acpi/prmt.c | 24 ++++++++++++++++++++++++
> > include/linux/prmt.h | 5 +++++
> > 2 files changed, 29 insertions(+)
> >
> > diff --git a/drivers/acpi/prmt.c b/drivers/acpi/prmt.c
> > index c78453c74ef5..1cfaa5957ac4 100644
> > --- a/drivers/acpi/prmt.c
> > +++ b/drivers/acpi/prmt.c
> > @@ -214,6 +214,30 @@ static struct prm_handler_info *find_prm_handler(const guid_t *guid)
> > #define UPDATE_LOCK_ALREADY_HELD 4
> > #define UPDATE_UNLOCK_WITHOUT_LOCK 5
> >
> > +int acpi_call_prm_handler(guid_t handler_guid, void *param_buffer)
> > +{
> > + struct prm_handler_info *handler = find_prm_handler(&handler_guid);
> > + struct prm_module_info *module = find_prm_module(&handler_guid);
> > + struct prm_context_buffer context;
> > + efi_status_t status;
> > +
> > + if (!module || !handler)
> > + return -ENODEV;
> > +
> > + memset(&context, 0, sizeof(context));
> > + ACPI_COPY_NAMESEG(context.signature, "PRMC");
> > + context.identifier = handler->guid;
> > + context.static_data_buffer = handler->static_data_buffer_addr;
> > + context.mmio_ranges = module->mmio_info;
> > +
> > + status = efi_call_acpi_prm_handler(handler->handler_addr,
> > + (u64)param_buffer,
> > + &context);
> > +
> > + return efi_status_to_err(status);
> > +}
>
> + linux-efi as Rafael wanted to make sure the environment is created properly
> for the EFI runtime services call...
>
This looks fine to me.
Reviewed-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
