[GIT PATCH] Another PCI fix for 2.6.12-rc6

[GIT PATCH] Another PCI fix for 2.6.12-rc6

[Greg KH]

Narendra from Broadcom pointed out that the following patch had not made
it into your tree (it was in mine for a long time, along with the -mm
releases).  It is needed for 2.6.12 because:
	"Broadcom already submitted the bnx2 driver for the 5706 gigabit
	driver which enables MSI on all systems that support PCI-X. That
	patch has already gone into 2.6.12-rc6. So if the MSI disable
	patch does not get into 2.6.12, anyone who uses the 5706 on the
	Serverworks chipset platform, will have interrupt failures."

Please pull from:
	rsync://rsync.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6.git/

The full patch will be sent to the linux-kernel and linux-pci mailing
lists, if anyone wants to see them.

thanks,

greg k-h

 drivers/pci/quirks.c |    6 ++++++
 1 files changed, 6 insertions(+)

-----

Narendra Sankar:
  PCI: MSI functionality broken on Serverworks GC chipset

[PATCH] PCI: MSI functionality broken on Serverworks GC chipset

[Greg KH]

[PATCH] PCI: MSI functionality broken on Serverworks GC chipset

MSI functionality is broken on the GC_LE x86 chipset that Serverworks
developed and that is being used in various platforms today. Broadcom is
going to push out to the kernel MSI enabled Gigabit drivers (in the very
near future), and we would like to make sure that MSI does not get
enabled on any platforms using the GC_LE chipset (device id 0x17).
Following the AMD 8131 example, I am including a patch to disable MSI
functionality when a GCNB_LE is detected. Please let me know if there
are any issues with this. This is a permanent fix for this chipset, as
the hardware will not be updated.

Signed-off-by: Narendra Sankar <nsankar@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
commit 1e06276704c101bd1ae7b62879faaffcd7496a3e
tree 0b983e8000ed7f57d189f68097a6e78ad5c33488
parent 76854ceac3ef3408ab9a50a2521147fb14779f58
author Narendra Sankar <nsankar@broadcom.com> Fri, 06 May 2005 14:12:05 -0700
committer Greg Kroah-Hartman <gregkh@suse.de> Thu, 09 Jun 2005 17:04:30 -0700

 drivers/pci/quirks.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -456,6 +456,12 @@ static void __init quirk_amd_8131_ioapic
 } 
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8131_APIC,         quirk_amd_8131_ioapic ); 
 
+static void __init quirk_svw_msi(struct pci_dev *dev)
+{
+	pci_msi_quirk = 1;
+	printk(KERN_WARNING "PCI: MSI quirk detected. pci_msi_quirk set.\n");
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_GCNB_LE, quirk_svw_msi );
 #endif /* CONFIG_X86_IO_APIC */
 
 

Re: [PATCH] PCI: MSI functionality broken on Serverworks GC chipset

[David S. Miller]

From: Greg KH <gregkh@suse.de>
Date: Thu, 9 Jun 2005 15:21:33 -0700

> [PATCH] PCI: MSI functionality broken on Serverworks GC chipset
> 
> MSI functionality is broken on the GC_LE x86 chipset that Serverworks
> developed and that is being used in various platforms today. Broadcom is
> going to push out to the kernel MSI enabled Gigabit drivers (in the very
> near future), and we would like to make sure that MSI does not get
> enabled on any platforms using the GC_LE chipset (device id 0x17).
> Following the AMD 8131 example, I am including a patch to disable MSI
> functionality when a GCNB_LE is detected. Please let me know if there
> are any issues with this. This is a permanent fix for this chipset, as
> the hardware will not be updated.
> 
> Signed-off-by: Narendra Sankar <nsankar@broadcom.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

"Broadcom's driver" already has MSI support and has a self-test that
checks if MSI operates correctly, and will back out of using MSI if
the MSI test does not pass.

So this patch is not needed for proper functioning of that driver.

This changelog description is very misleading, at best.

Re: [GIT PATCH] Another PCI fix for 2.6.12-rc6

[David S. Miller]

From: Greg KH <gregkh@suse.de>
Date: Thu, 9 Jun 2005 15:20:33 -0700

> 	"Broadcom already submitted the bnx2 driver for the 5706 gigabit
> 	driver which enables MSI on all systems that support PCI-X. That
> 	patch has already gone into 2.6.12-rc6. So if the MSI disable
> 	patch does not get into 2.6.12, anyone who uses the 5706 on the
> 	Serverworks chipset platform, will have interrupt failures."

The bnx2 driver can get the MSI test added to it just like the tg3
driver does.  I don't see why the same code wasn't propagated.  Either
both drivers need that MSI test code, or both do not.

That doesn't make any sense, one testing for correct MSI functionality
while the other does not.

Re: [GIT PATCH] Another PCI fix for 2.6.12-rc6

[Narendra Sankar]

David S. Miller wrote:

>From: Greg KH <gregkh@suse.de>
>Date: Thu, 9 Jun 2005 15:20:33 -0700
>
>  
>
>>	"Broadcom already submitted the bnx2 driver for the 5706 gigabit
>>	driver which enables MSI on all systems that support PCI-X. That
>>	patch has already gone into 2.6.12-rc6. So if the MSI disable
>>	patch does not get into 2.6.12, anyone who uses the 5706 on the
>>	Serverworks chipset platform, will have interrupt failures."
>>    
>>
>
>The bnx2 driver can get the MSI test added to it just like the tg3
>driver does.  I don't see why the same code wasn't propagated.  Either
>both drivers need that MSI test code, or both do not.
>
>That doesn't make any sense, one testing for correct MSI functionality
>while the other does not.
>
>
>  
>
Hi everyone

The platform quirk is valid for other PCI-X devices that try to enable 
MSI on that Serverworks chipset. When I submitted the msi quirk patch, 
the bnx2 driver did not have the msi check. I guess it got added. 
Different parts of the organization :(.

However the fact that MSI functionality on the GC_LE is broken could 
potentially cause problems with other devices that try to enable MSI. 
This is the only version of the chipset that the functionality is broken 
on. Other variants have working MSI implementations.

So it would still be useful to have this patch in, would it not?

Thanks
Naren Sankar
Broadcom/Serverworks.

Re: [GIT PATCH] Another PCI fix for 2.6.12-rc6

[David S. Miller]

From: "Narendra Sankar" <nsankar@broadcom.com>
Date: Thu, 09 Jun 2005 15:48:28 -0700

> So it would still be useful to have this patch in, would it not?

Absolutely, the patch should go in.

I just want to make sure the descrepency between the two Broadcom
drivers gets resolved.  TG3 does a MSI correctness check, BNX2
does not.  And this is what doesn't make any sense.

Re: [GIT PATCH] Another PCI fix for 2.6.12-rc6

[Roland Dreier]

    Narendra> So it would still be useful to have this patch in, would
    Narendra> it not?

Yes, we should use the PCI quirk to disable MSI when we know a host
bridge does not support MSI.

 - R.

Re: [GIT PATCH] Another PCI fix for 2.6.12-rc6

[Narendra Sankar]

David S. Miller wrote:

>From: "Narendra Sankar" <nsankar@broadcom.com>
>Date: Thu, 09 Jun 2005 15:48:28 -0700
>
>  
>
>>So it would still be useful to have this patch in, would it not?
>>    
>>
>
>Absolutely, the patch should go in.
>
>I just want to make sure the descrepency between the two Broadcom
>drivers gets resolved.  TG3 does a MSI correctness check, BNX2
>does not.  And this is what doesn't make any sense.
>
>  
>
Actually looking at the bnx2.c code from jeffG 2.6.13 git tree, it seems 
that it also tests for MSIs being delivered.

So both tg3 and bnx2 test for MSI correctness.

My original comment when submitting the patch, was under the assumption 
that these tests were not being done. However that code has got added to 
both drivers.

Naren