[PATCH] Update MCP55 quirk to not affect non HyperTransport variants

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



I wrote this quirk awhile ago to properly setup MCP55 chips on hypertransport
busses so that interrupts reached whatever cpu happend to boot the kdump kernel.
while that works well, it was recently shown to me that a a non-hypertransport
variant of the MCP55 exists, and on those system the register that this quirk
manipulates causes hangs if you write to it.  Since the quirk was only meant to
handle errors found on MCP55 chips that have a HT interface, this patch adds a
filter to make sure the chip is an HT capable before making the needed register
adjustment.  This lets the broken MCP55s work with kdump while not breaking the
non-HT variants.

Resolves https://bugzilla.kernel.org/show_bug.cgi?id=23952

Tested successfully by the reporter and myself.

Reported-by: Mathieu BÃrard <mathieu@xxxxxxxxxx>
CC: linux-pci@xxxxxxxxxxxxxxx
CC: kexec@xxxxxxxxxxxxxxxxxxx
CC: Vivek Goyal <vgoyal@xxxxxxxxxx>
CC: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx>
Signed-off-by: Neil Horman <nhorman@xxxxxxxxxxxxx>
---
 drivers/pci/quirks.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 6f9350c..313c0bd 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -2329,6 +2329,9 @@ static void __devinit nvbridge_check_legacy_irq_routing(struct pci_dev *dev)
 {
 	u32 cfg;
 
+	if (!pci_find_capability(dev, PCI_CAP_ID_HT))
+		return;
+
 	pci_read_config_dword(dev, 0x74, &cfg);
 
 	if (cfg & ((1 << 2) | (1 << 15))) {
-- 
1.7.2.3

--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [DMA Engine]     [Linux Coverity]     [Linux USB]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Greybus]

  Powered by Linux