On Fri, Dec 17, 2021 at 12:03:02AM +0800, Chen Yu wrote: > Introduce the pfr_update driver which can be used for Platform Firmware > Runtime code injection and driver update [1]. The user is expected to > provide the EFI capsule, and pass it to the driver by writing the capsule > to a device special file. The capsule is transferred by the driver to the > platform firmware with the help of an ACPI _DSM method under the special > ACPI Platform Firmware Runtime Update device (INTC1080), and the actual > firmware update is carried out by the low-level Management Mode code in > the platform firmware. > > This patch allows certain pieces of the platform firmware to be > updated on the fly while the system is running (runtime) without the > need to restart it, which is key in the cases when the system needs to > be available 100% of the time and it cannot afford the downtime related > to restarting it, or when the work carried out by the system is > particularly important, so it cannot be interrupted, and it is not > practical to wait until it is complete. > > Link: https://uefi.org/sites/default/files/resources/Intel_MM_OS_Interface_Spec_Rev100.pdf # [1] > Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> > Cc: Ard Biesheuvel <ardb@xxxxxxxxxx> > Cc: Ashok Raj <ashok.raj@xxxxxxxxx> > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Cc: Len Brown <lenb@xxxxxxxxxx> > Cc: Mike Rapoport <rppt@xxxxxxxxxx> > Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> > Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx> > + [cut] > +static int start_update(int action, struct pfru_device *pfru_dev) > +{ > + union acpi_object *out_obj, in_obj, in_buf; > + struct pfru_updated_result update_result; > + acpi_handle handle; > + int ret = -EINVAL; > + > + memset(&in_obj, 0, sizeof(in_obj)); > + memset(&in_buf, 0, sizeof(in_buf)); > + in_obj.type = ACPI_TYPE_PACKAGE; > + in_obj.package.count = 1; > + in_obj.package.elements = &in_buf; > + in_buf.type = ACPI_TYPE_INTEGER; > + in_buf.integer.value = action; > + > + handle = ACPI_HANDLE(pfru_dev->parent_dev); > + out_obj = acpi_evaluate_dsm_typed(handle, &pfru_guid, > + pfru_dev->rev_id, PFRU_FUNC_START, > + &in_obj, ACPI_TYPE_PACKAGE); > + if (!out_obj) > + return ret; > + > + if (out_obj->package.count < UPDATE_NR_IDX || > + out_obj->package.elements[UPDATE_STATUS_IDX].type != ACPI_TYPE_INTEGER || > + out_obj->package.elements[UPDATE_EXT_STATUS_IDX].type != ACPI_TYPE_INTEGER || > + out_obj->package.elements[UPDATE_AUTH_TIME_LOW_IDX].type != ACPI_TYPE_INTEGER || > + out_obj->package.elements[UPDATE_AUTH_TIME_HI_IDX].type != ACPI_TYPE_INTEGER || > + out_obj->package.elements[UPDATE_EXEC_TIME_LOW_IDX].type != ACPI_TYPE_INTEGER || > + out_obj->package.elements[UPDATE_EXEC_TIME_HI_IDX].type != ACPI_TYPE_INTEGER) > + goto free_acpi_buffer; > + > + update_result.status = > + out_obj->package.elements[UPDATE_STATUS_IDX].integer.value; Thanks for Hongyu's testing, the status should be cascaded to user space. Will fix it in next version. Thanks, Chenyu
