From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-gw2-out.broadcom.com ([216.31.210.63]:27588 "EHLO mail-gw2-out.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030288AbbD1QiR (ORCPT ); Tue, 28 Apr 2015 12:38:17 -0400 Message-ID: <553FB772.1000202@broadcom.com> Date: Tue, 28 Apr 2015 09:38:10 -0700 From: Ray Jui MIME-Version: 1.0 To: Yijing Wang , Bjorn Helgaas CC: , , Arnd Bergmann , Subject: Re: [PATCH Part1 v11 5/5] PCI: iproc: Use pci_scan_root_bus() instead of pci_create_root_bus() References: <1430204499-19571-1-git-send-email-wangyijing@huawei.com> <1430204499-19571-6-git-send-email-wangyijing@huawei.com> In-Reply-To: <1430204499-19571-6-git-send-email-wangyijing@huawei.com> Content-Type: text/plain; charset="windows-1252" Sender: linux-pci-owner@vger.kernel.org List-ID: Hi Yijing, On 4/28/2015 12:01 AM, Yijing Wang wrote: > Pci_bus_add_devices() was ripped out of pci_scan_root_bus(). > Now pci_scan_root_bus() == pci_create_root_bus() + > pci_scan_child_bus() if busn resource is supplied. > iproc added the busn resource to resources list > in of_pci_get_host_bridge_resources(). So it should be safe > to use pci_scan_root_bus() instead. > > Signed-off-by: Yijing Wang > CC: Ray Jui > --- > drivers/pci/host/pcie-iproc.c | 5 ++--- > 1 files changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c > index 329e1b5..9622ebf 100644 > --- a/drivers/pci/host/pcie-iproc.c > +++ b/drivers/pci/host/pcie-iproc.c > @@ -210,10 +210,10 @@ int iproc_pcie_setup(struct iproc_pcie *pcie) > > pcie->sysdata.private_data = pcie; > > - bus = pci_create_root_bus(pcie->dev, 0, &iproc_pcie_ops, > + bus = pci_scan_root_bus(pcie->dev, 0, &iproc_pcie_ops, > &pcie->sysdata, pcie->resources); > if (!bus) { > - dev_err(pcie->dev, "unable to create PCI root bus\n"); > + dev_err(pcie->dev, "unable to scan PCI root bus\n"); > ret = -ENOMEM; > goto err_power_off_phy; > } iproc_pcie_check_link is called here by using the 'bus' structure returned from pci_create_root_bus. In iproc_pcie_check_link, we configure root bus class to PCI_CLASS_BRIDGE_PCI and validate to ensure a stable link between RC and EP can be detected. > @@ -227,7 +227,6 @@ int iproc_pcie_setup(struct iproc_pcie *pcie) > > iproc_pcie_enable(pcie); Here we enable INTx support for our RC controller. > > - pci_scan_child_bus(bus); Here, if pci_scan_child_bus is moved to before iproc_pcie_check_link, I don't think it would work (although I have not tested this). An alternative is to use a dummy bus structure to feed into iproc_pcie_check_link, and call iproc_pcie_check_link and iproc_pcie_enable before pci_scan_root_bus. But the reason I put the link check code in between pci_create_root_bus and pci_scan_child_bus was to avoid using a dummy bus structure, :) > pci_assign_unassigned_bus_resources(bus); > pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci); > pci_bus_add_devices(bus); > Thanks, Ray