From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <1434106314.30003.199.camel@citrix.com> Subject: Re: [PATCH 1/1] PCI: X-Gene: Disable Configuration Request Retry Status for X-Gene v1 PCIe From: Ian Campbell To: Duc Dang CC: Bjorn Helgaas , , , , Marcin Juszkiewicz , Tanmay Inamdar , Date: Fri, 12 Jun 2015 11:51:54 +0100 In-Reply-To: <1434053294-10962-1-git-send-email-dhdang@apm.com> References: <1434053294-10962-1-git-send-email-dhdang@apm.com> Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: On Thu, 2015-06-11 at 13:08 -0700, Duc Dang wrote: > X-Gene v1 PCIe controller has a bug in Configuration Request Retry > Status (CRS) logic: > When CPU tries to read Vendor ID and Device ID of not-existed > remote device, the controller returns 0xFFFF0001 instead of > 0xFFFFFFFF; this will add significant delay in boot time as > pci_bus_read_dev_vendor_id will wait for 60 seconds before > giving up. > > So for X-Gene v1 PCIe controllers, disable CRS capability > advertisement by clearing CRS Software Visibility bit before > returning the Root Capability value to the callers. This is done > by implementing X-Gene PCIe specific xgene_pcie_config_read32 for > CFG read accesses to replace the generic default pci_generic_config_read32 > function. > > Signed-off-by: Duc Dang Applied onto v4.1-rc7 and: Tested-by: Ian Campbell Thanks!