From mboxrd@z Thu Jan 1 00:00:00 1970 From: Len Brown Subject: Re: [PATCH] fix(Fix _STA checking in acpi_bus_add) Date: 12 May 2004 17:49:38 -0400 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: <1084398577.12352.186.camel@dhcppc4> References: <20040428142557.GB22558@parcelfarce.linux.theplanet.co.uk> <200404280934.26381.bjorn.helgaas@hp.com> <1084336805.12353.143.camel@dhcppc4> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1084336805.12353.143.camel-D2Zvc0uNKG8@public.gmane.org> Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Simon Derr Cc: Bjorn Helgaas , Matthew Wilcox , ACPI Developers List-Id: linux-acpi@vger.kernel.org The ACPI spec gurus say that as of 2.0c, _STA.functional is meaningless unless _STA.present. However, they also say that the (_STA.functional && !_STA.present) implementation was intentional -- apparently to trick some OSPM into using a resource for initialization only, but to not load a driver. So... I'm advocating that the spec be clarified to explicitly allow or disallow this idiom. In the mean-time, Bjorn's patch is now present in the acpi-test tree. -Len On Wed, 2004-05-12 at 00:40, Len Brown wrote: > As this is needed by more than just Big Sur, > I'm okay with applying Bjorn's workaround to acpi-test > (and thus -mm) while we wait for definitive word > from the spec writers. We can always back it out > or make it system specific later. I have no fear > that we'll break docking stations, because at this > point we have no docking station support... > > thanks, > -Len > > On Thu, 2004-04-29 at 04:18, Simon Derr wrote: > > On Wed, 28 Apr 2004, Bjorn Helgaas wrote: > > > > > Is your box based on Intel chipsets and/or firmware? You might be > > Indeed. > > > > > suffering from the problem I described here: > > > > > > https://sourceforge.net/mailarchive/message.php?msg_id=6923358 > > > > > > Intel firmware seems to describe the PCI root bridge where chipset > > > configuration space lives with _STA==0x8. The spec says this means > > > "functional, but not present". The current Linux code ignores things > > > that are "not present". > > > > I tried your patch and it works perfectly. Thank you. > > This chipset/firmware is probably very common in the ia64 world so I think > > it might be a good idea to include your patch in the stock Linux kernel. > > > > Simon. > > > > This is just your patch with updated line offsets, applies cleanly to > > Linux 2.6.5: > > > > --- linux-2.6.5-vanilla/drivers/acpi/bus.c Sun Apr 4 05:37:24 2004 > > +++ linux-2.6.5/drivers/acpi/bus.c Thu Apr 29 09:43:14 2004 > > @@ -112,6 +112,14 @@ > > else > > STRUCT_TO_INT(device->status) = 0x0F; > > > > + if (device->status.functional && !device->status.present) { > > + printk(KERN_WARNING PREFIX "Device [%s] status [%08x]: " > > + "functional but not present; setting present\n", > > + device->pnp.bus_id, > > + (u32) STRUCT_TO_INT(device->status)); > > + device->status.present = 1; > > + } > > + > > ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n", > > device->pnp.bus_id, (u32) STRUCT_TO_INT(device->status))); > > > > > > > > ------------------------------------------------------- > > This SF.Net email is sponsored by: Oracle 10g > > Get certified on the hottest thing ever to hit the market... Oracle 10g. > > Take an Oracle 10g class now, and we'll give you the exam FREE. > > http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click > > _______________________________________________ > > Acpi-devel mailing list > > Acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org > > https://lists.sourceforge.net/lists/listinfo/acpi-devel > > > > ------------------------------------------------------- > This SF.Net email is sponsored by Sleepycat Software > Learn developer strategies Cisco, Motorola, Ericsson & Lucent use to deliver > higher performing products faster, at low TCO. > http://www.sleepycat.com/telcomwpreg.php?From=osdnemail3 > _______________________________________________ > Acpi-devel mailing list > Acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org > https://lists.sourceforge.net/lists/listinfo/acpi-devel ------------------------------------------------------- This SF.Net email is sponsored by Sleepycat Software Learn developer strategies Cisco, Motorola, Ericsson & Lucent use to deliver higher performing products faster, at low TCO. http://www.sleepycat.com/telcomwpreg.php?From=osdnemail3