Message ID | 20190325093947.32633-13-kishon@ti.com |
---|---|
State | Accepted |
Commit | f316a2b53cd7f37963ae20ec7072eb27a349a4ce |
Headers | show |
Series | None | expand |
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 <kishon@ti.com> >>>> --- >>>> 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 >> >
Hi Lorenzo, On 12/04/19 4:41 PM, Lorenzo Pieralisi 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. > > That can't have much to do with ARM32<->ARM64, it is rather a platform > integration issue AFAICS. Russell has a point, this has to be documented > I can do it for you but I need additional information. Right now only ARM32 exports hook_fault_code which was used by K2G (ARM32 platform) and since AM654 (ARM64 platform) uses the same driver, it'll result in compilation error. Also AM654 doesn't require hook_fault_code (or something similar) because it doesn't throw bus error on accessing PCIe address space when PCI device is not connected). Are you looking for some other information? Thanks Kishon > > Thanks, > Lorenzo > >> Thanks >> Kishon >> >>> >>> Thanks, >>> Lorenzo >>> >>>> allow hook_fault_code to be compiled only for ARM32. >>>> >>>> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com> >>>> --- >>>> 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 >>>>
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);
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, allow hook_fault_code to be compiled only for ARM32. Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com> --- drivers/pci/controller/dwc/pci-keystone.c | 4 ++++ 1 file changed, 4 insertions(+) -- 2.17.1