Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751686AbXA3TSE (ORCPT ); Tue, 30 Jan 2007 14:18:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751684AbXA3TSD (ORCPT ); Tue, 30 Jan 2007 14:18:03 -0500 Received: from atlrel7.hp.com ([156.153.255.213]:48934 "EHLO atlrel7.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751679AbXA3TSA (ORCPT ); Tue, 30 Jan 2007 14:18:00 -0500 From: Bjorn Helgaas To: =?iso-8859-15?q?Fr=E9d=E9ric_Riss?= Subject: Re: [PATCH] EFI x86: pass firmware call parameters on the stack Date: Tue, 30 Jan 2007 12:17:47 -0700 User-Agent: KMail/1.9.5 Cc: linux-kernel@vger.kernel.org, artiom.myaskouvskey@intel.com, akpm@osdl.org, Linus Torvalds References: <1170183678.21603.73.camel@funkylaptop> In-Reply-To: <1170183678.21603.73.camel@funkylaptop> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 8bit Content-Disposition: inline Message-Id: <200701301217.47520.bjorn.helgaas@hp.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3554 Lines: 76 On Tuesday 30 January 2007 12:01, Fr?d?ric Riss wrote: > When calling into an EFI firmware, the parameters need to be passed on > the stack. The recent change to use -mregparm=3 breaks x86 EFI support. > This patch is needed to allow the new Intel-based Macs to suspend to ram > when run in EFI mode (efi.get_time is called during the suspend phase). > ... > This patch fixes the issue for x86, but the file is also used by IA64. I > would have used asmlinkage to force arguments on the stack, but it has a > special meaning on IA64, thus I used a raw regparm(0) GCC attribute. > This attribute is documented only for x86, I hope it has no side effect > on other archs. It seems wrong to put this sort of architecture-dependent stuff in an architecture-independent file. If EFI needs a specific calling convention on x86, x86 should provide wrappers that guarantee that convention. ia64 already provides such wrappers (phys_get_time(), virt_get_time(), etc). > diff --git a/include/linux/efi.h b/include/linux/efi.h > index df1c918..1db5321 100644 > --- a/include/linux/efi.h > +++ b/include/linux/efi.h > @@ -157,25 +157,35 @@ typedef struct { > unsigned long reset_system; > } efi_runtime_services_t; > > -typedef efi_status_t efi_get_time_t (efi_time_t *tm, efi_time_cap_t *tc); > -typedef efi_status_t efi_set_time_t (efi_time_t *tm); > +typedef efi_status_t efi_get_time_t (efi_time_t *tm, efi_time_cap_t *tc) > + __attribute__((regparm(0))); > +typedef efi_status_t efi_set_time_t (efi_time_t *tm) > + __attribute__((regparm(0))); > typedef efi_status_t efi_get_wakeup_time_t (efi_bool_t *enabled, efi_bool_t *pending, > - efi_time_t *tm); > -typedef efi_status_t efi_set_wakeup_time_t (efi_bool_t enabled, efi_time_t *tm); > + efi_time_t *tm) > + __attribute__((regparm(0))); > +typedef efi_status_t efi_set_wakeup_time_t (efi_bool_t enabled, efi_time_t *tm) > + __attribute__((regparm(0))); > typedef efi_status_t efi_get_variable_t (efi_char16_t *name, efi_guid_t *vendor, u32 *attr, > - unsigned long *data_size, void *data); > + unsigned long *data_size, void *data) > + __attribute__((regparm(0))); > typedef efi_status_t efi_get_next_variable_t (unsigned long *name_size, efi_char16_t *name, > - efi_guid_t *vendor); > + efi_guid_t *vendor) > + __attribute__((regparm(0))); > typedef efi_status_t efi_set_variable_t (efi_char16_t *name, efi_guid_t *vendor, > unsigned long attr, unsigned long data_size, > - void *data); > -typedef efi_status_t efi_get_next_high_mono_count_t (u32 *count); > + void *data) > + __attribute__((regparm(0))); > +typedef efi_status_t efi_get_next_high_mono_count_t (u32 *count) > + __attribute__((regparm(0))); > typedef void efi_reset_system_t (int reset_type, efi_status_t status, > - unsigned long data_size, efi_char16_t *data); > + unsigned long data_size, efi_char16_t *data) > + __attribute__((regparm(0))); > typedef efi_status_t efi_set_virtual_address_map_t (unsigned long memory_map_size, > unsigned long descriptor_size, > u32 descriptor_version, > - efi_memory_desc_t *virtual_map); > + efi_memory_desc_t *virtual_map) > + __attribute__((regparm(0))); > > /* > * EFI Configuration Table and GUID definitions > > > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/