From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kishon Vijay Abraham I Subject: Re: [PATCH v3 12/26] PCI: keystone: Prevent ARM32 specific code to be compiled for ARM64 Date: Fri, 12 Apr 2019 16:32:10 +0530 Message-ID: <47ea91f7-bbc1-187d-6f75-e2e6460f90a0@ti.com> References: <20190325093947.32633-1-kishon@ti.com> <20190325093947.32633-13-kishon@ti.com> <20190411150332.GC6862@red-moon> <20190412093154.7wj4dmm3oppvv32m@shell.armlinux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190412093154.7wj4dmm3oppvv32m@shell.armlinux.org.uk> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Russell King - ARM Linux admin Cc: Lorenzo Pieralisi , devicetree@vger.kernel.org, Jesper Nilsson , Arnd Bergmann , Greg Kroah-Hartman , Gustavo Pimentel , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@axis.com, Minghuan Lian , Rob Herring , Murali Karicheri , Jingoo Han , Bjorn Helgaas , Mingkai Hu , linux-omap@vger.kernel.org, Roy Zang , linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org Hi Russell, On 12/04/19 3:01 PM, Russell King - ARM Linux admin wrote: > On Fri, Apr 12, 2019 at 02:20:06PM +0530, Kishon Vijay Abraham I wrote: >> Hi Lorenzo, >> >> On 11/04/19 8:33 PM, Lorenzo Pieralisi wrote: >>> On Mon, Mar 25, 2019 at 03:09:33PM +0530, Kishon Vijay Abraham I wrote: >>>> hook_fault_code is an ARM32 specific API for hooking into data abort. >>>> Since pci-keystone.c will be used for AM65X platforms which is an >>>> ARM64 platform, >>> >>> Hi Kishon, >>> >>> How is the problem plugged by the fault hook fixed on ARM64 ? >> >> At least in AM654 platform, I don't see a bus error when PCIe device is not >> connected but returns 0xffffffff. So there is no necessary for hook_fault_code >> in AM654 platform. > > ... which needs to be explained somewhere, either in the commit > message or comments in the file, so that years later when someone > has to look at this code, they know why it is the way that it is. > > When writing commits, please think about whether there is enough > information to understand the change in ten years time. sure, I'll fix this one. Lorenzo, let me know if you want me to resend with updated commit log. Thanks Kishon > >> >> Thanks >> Kishon >> >>> >>> Thanks, >>> Lorenzo >>> >>>> allow hook_fault_code to be compiled only for ARM32. >>>> >>>> Signed-off-by: Kishon Vijay Abraham I >>>> --- >>>> drivers/pci/controller/dwc/pci-keystone.c | 4 ++++ >>>> 1 file changed, 4 insertions(+) >>>> >>>> diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c >>>> index dfe54553d832..93296d434f40 100644 >>>> --- a/drivers/pci/controller/dwc/pci-keystone.c >>>> +++ b/drivers/pci/controller/dwc/pci-keystone.c >>>> @@ -710,6 +710,7 @@ static int ks_pcie_config_legacy_irq(struct keystone_pcie *ks_pcie) >>>> return ret; >>>> } >>>> >>>> +#ifdef CONFIG_ARM >>>> /* >>>> * When a PCI device does not exist during config cycles, keystone host gets a >>>> * bus error instead of returning 0xffffffff. This handler always returns 0 >>>> @@ -729,6 +730,7 @@ static int ks_pcie_fault(unsigned long addr, unsigned int fsr, >>>> >>>> return 0; >>>> } >>>> +#endif >>>> >>>> static int __init ks_pcie_init_id(struct keystone_pcie *ks_pcie) >>>> { >>>> @@ -778,12 +780,14 @@ static int __init ks_pcie_host_init(struct pcie_port *pp) >>>> if (ret < 0) >>>> return ret; >>>> >>>> +#ifdef CONFIG_ARM >>>> /* >>>> * PCIe access errors that result into OCP errors are caught by ARM as >>>> * "External aborts" >>>> */ >>>> hook_fault_code(17, ks_pcie_fault, SIGBUS, 0, >>>> "Asynchronous external abort"); >>>> +#endif >>>> >>>> ks_pcie_start_link(pci); >>>> dw_pcie_wait_for_link(pci); >>>> -- >>>> 2.17.1 >>>> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >> >