Hi Liviu, Actually your suggested implementation of pci_domain_nr is working perfectly. My bad for earlier email. I did not implement it correctly. Thanks, Tanmay On Mon, Mar 3, 2014 at 4:42 PM, Tanmay Inamdar <tinamdar@xxxxxxx> wrote: > Hello, > > Please see inline. > > On Mon, Mar 3, 2014 at 3:51 PM, Liviu Dudau <liviu@xxxxxxxxxxx> wrote: >> On Mon, Mar 03, 2014 at 03:14:47PM -0800, Tanmay Inamdar wrote: >>> Hello Liviu, >>> >>> Thanks for fixing up domain_nr. Now I have moved on further to a new >>> domain_nr related warning dump :-) >>> >>> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- >>> xgene-pcie 1f500000.pcie: (rc) x8 gen-3 link up >>> pci_bus 0001:00: scanning bus >>> pci_setup_device:1101 domain_nr = 1 >>> pci 0001:00:00.0: [e008:e004] type 01 class 0x060400 >>> pci 0001:00:00.0: reg 0x10: [mem 0x4000000000-0x7fffffffff 64bit] >>> pci 0001:00:00.0: calling xgene_pcie_fixup_bridge+0x0/0x80 >>> pci 0001:00:00.0: Hiding X-Gene pci host bridge resources 0001:00:00.0 >>> pci 0001:00:00.0: supports D1 D2 >>> pci_bus 0001:00: fixups for bus >>> pci 0001:00:00.0: scanning [bus 03-03] behind bridge, pass 0 >>> pci 0001:00:00.0: bridge configuration invalid ([bus 03-03]), reconfiguring >>> pci 0001:00:00.0: scanning [bus 00-00] behind bridge, pass 1 >>> ** pci_scan_bridge:855 pci_domain_nr(bus) = 1 >>> ** pci_alloc_child_bus:681 pci_domain_nr(bus) = 1 >>> pci_bus 0001:01: scanning bus >>> pci_setup_device:1101 domain_nr = 0 >> >> Why does the domain_nr change here? > > The bridge device pointer for parent and child should be same right? I > think this is not the case here. Please look at the log at the bottom > that I captured after trying your suggestions. > >> >>> pci 0000:01:00.0: [15b3:1003] type 00 class 0x020000 >>> pci 0000:01:00.0: reg 0x10: [mem 0x00100000-0x001fffff 64bit] >>> pci 0000:01:00.0: reg 0x18: [mem 0x00800000-0x00ffffff 64bit pref] >>> pci 0000:01:00.0: reg 0x30: [mem 0x01000000-0x010fffff pref] >>> ------------[ cut here ]------------ >>> WARNING: CPU: 0 PID: 1 at >>> /home/tinamdar/work/open-source/linux/fs/sysfs/dir.c:52 >>> sysfs_warn_dup+0x80/0xc0() >>> sysfs: cannot create duplicate filename '/bus/pci/devices/0000:01:00.0' >>> Modules linked in: >>> CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.14.0-rc5+ #40 >>> Call trace: >>> [<ffffffc000088180>] dump_backtrace+0x0/0x140 >>> [<ffffffc0000882d0>] show_stack+0x10/0x20 >>> [<ffffffc0004f65ac>] dump_stack+0x74/0xc4 >>> [<ffffffc000096e04>] warn_slowpath_common+0x84/0xc0 >>> [<ffffffc000096e8c>] warn_slowpath_fmt+0x4c/0x60 >>> [<ffffffc0001b83dc>] sysfs_warn_dup+0x7c/0xc0 >>> [<ffffffc0001b8894>] sysfs_do_create_link_sd.isra.2+0xf4/0x100 >>> [<ffffffc0001b88bc>] sysfs_create_link+0x1c/0x40 >>> [<ffffffc0003250b0>] bus_add_device+0x110/0x1c0 >>> [<ffffffc000322f1c>] device_add+0x31c/0x520 >>> [<ffffffc0002c444c>] pci_device_add+0xec/0x140 >>> [<ffffffc0004f1758>] pci_scan_single_device+0x98/0xe0 >>> [<ffffffc0002c44e8>] pci_scan_slot+0x48/0x120 >>> [<ffffffc0002c5368>] pci_scan_child_bus+0x48/0x140 >>> [<ffffffc0002c522c>] pci_scan_bridge+0x4ec/0x5e0 >>> [<ffffffc0002c53c8>] pci_scan_child_bus+0xa8/0x140 >>> [<ffffffc0004f1b30>] pci_rescan_bus+0x10/0x40 >>> [<ffffffc0006a12ac>] xgene_pcie_probe_bridge+0x660/0x72c >>> [<ffffffc000327d20>] platform_drv_probe+0x20/0x60 >>> [<ffffffc000325e30>] really_probe+0xf0/0x220 >>> [<ffffffc000326080>] __driver_attach+0xa0/0xc0 >>> [<ffffffc000323ed4>] bus_for_each_dev+0x54/0xa0 >>> [<ffffffc0003258bc>] driver_attach+0x1c/0x40 >>> [<ffffffc00032548c>] bus_add_driver+0x14c/0x220 >>> [<ffffffc00032683c>] driver_register+0x5c/0x120 >>> [<ffffffc000327cdc>] __platform_driver_register+0x5c/0x80 >>> [<ffffffc0006a0c40>] xgene_pcie_driver_init+0x14/0x20 >>> [<ffffffc0000814c0>] do_one_initcall+0xe0/0x160 >>> [<ffffffc00068c934>] kernel_init_freeable+0x134/0x1d8 >>> [<ffffffc0004f07ac>] kernel_init+0xc/0xe0 >>> ---[ end trace 3ee052d463aab7f3 ]--- >>> ------------[ cut here ]------------ >>> WARNING: CPU: 0 PID: 1 at >>> /home/tinamdar/work/open-source/linux/drivers/pci/probe.c:1380 >>> pci_device_add+0x128/0x140() >>> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- >>> >>> I have made a small fix above your patch. After the fix is applied, >>> dumps are gone and the enumeration finishes up smoothly for all the >>> ports. >>> Since the change is small, just pasting it here. Please review and >>> apply if it's clean. >> >> Honestly, I have no idea. I kept staring at the code for a better part of an hour >> trying to decipher what the intent of the code was, without too much progress. I >> still don't understand why the code in pci_alloc_child_bus() takes a shortcut when >> the bridge argument is NULL when in my opinion it should use parent->bridge instead >> and continue as normal. >> >>> >>> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c >>> index a12cda5..aac8366 100644 >>> --- a/drivers/pci/probe.c >>> +++ b/drivers/pci/probe.c >>> @@ -693,7 +693,7 @@ static struct pci_bus *pci_alloc_child_bus(struct >>> pci_bus *parent, >>> } >>> >>> child->self = bridge; >>> - child->bridge = get_device(&bridge->dev); >>> + child->bridge = get_device(parent->bridge); >>> child->dev.parent = child->bridge; >> >> Hmm, not sure why this is needed. What does get_device(&bridge->dev) >> return for you? The next line sets child->dev.parent to child->bridge, >> but with your change I'm not sure we end up using the correct parent. >> >> Can you try to revert your change and modify the implementation of pci_domain_nr() in arm64 >> to look like this: >> >> static inline int pci_domain_nr(struct pci_bus *bus) >> { >> struct pci_host_bridge *bridge; >> >> while (bus->parent) >> bus = bus->parent; >> >> bridge = to_pci_host_bridge(bus->bridge); >> if (bridge) >> return bridge->domain_nr; >> >> return 0; >> } >> > > This did not work for me. > > >> Please let me know what results you get. >> > I am printing following values > > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > index a12cda5..c89f86a 100644 > --- a/drivers/pci/probe.c > +++ b/drivers/pci/probe.c > @@ -695,6 +695,8 @@ static struct pci_bus *pci_alloc_child_bus(struct > pci_bus *parent, > child->self = bridge; > child->bridge = get_device(&bridge->dev); > child->dev.parent = child->bridge; > + printk("%s:%d bus = %p , bridge_dev = %p, domain = %d\n", > + __func__, __LINE__, child, child->bridge, > pci_domain_nr(parent)); > pci_set_bus_of_node(child); > pci_set_bus_speed(child); > > @@ -1095,6 +1097,8 @@ int pci_setup_device(struct pci_dev *dev) > dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus), > dev->bus->number, PCI_SLOT(dev->devfn), > PCI_FUNC(dev->devfn)); > + printk("%s:%d bus = %p , bridge_dev = %p, domain = %d\n", > + __func__, __LINE__, dev->bus, dev->bus->bridge, > pci_domain_nr(dev->bus)); > > pci_read_config_dword(dev, PCI_CLASS_REVISION, &class); > dev->revision = class & 0xff; > > Following looks suspicious to me. > > bridge_dev = ffffffc7e03ffc00 for bus 0 in domain 1 while bridge_dev = > ffffffc7e03f7098 for bus 1 in domain 1. > > Log --> > ----------------------------------------------------------------------------------------------------------------------------- > xgene-pcie 1f500000.pcie: (rc) x8 gen-3 link up > pci_bus 0001:00: scanning bus > pci_setup_device:1101 bus = ffffffc7e0060400 , bridge_dev = > ffffffc7e03ffc00, domain = 1 > pci 0001:00:00.0: [e008:e004] type 01 class 0x060400 > pci 0001:00:00.0: reg 0x10: [mem 0x4000000000-0x7fffffffff 64bit] > pci 0001:00:00.0: calling xgene_pcie_fixup_bridge+0x0/0x80 > pci 0001:00:00.0: Hiding X-Gene pci host bridge resources 0001:00:00.0 > pci 0001:00:00.0: supports D1 D2 > pci_bus 0001:00: fixups for bus > pci 0001:00:00.0: scanning [bus 03-03] behind bridge, pass 0 > pci 0001:00:00.0: bridge configuration invalid ([bus 03-03]), reconfiguring > pci 0001:00:00.0: scanning [bus 00-00] behind bridge, pass 1 > pci_alloc_child_bus:699 bus = ffffffc7e0063000 , bridge_dev = > ffffffc7e03f7098, domain = 1 > pci_bus 0001:01: scanning bus > pci_setup_device:1101 bus = ffffffc7e0063000 , bridge_dev = > ffffffc7e03f7098, domain = 0 > pci 0000:01:00.0: [15b3:1003] type 00 class 0x020000 > pci 0000:01:00.0: reg 0x10: [mem 0x00100000-0x001fffff 64bit] > pci 0000:01:00.0: reg 0x18: [mem 0x00800000-0x00ffffff 64bit pref] > pci 0000:01:00.0: reg 0x30: [mem 0x01000000-0x010fffff pref] > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 1 at > /home/tinamdar/work/open-source/linux/fs/sysfs/dir.c:52 > sysfs_warn_dup+0x80/0xc0() > sysfs: cannot create duplicate filename '/bus/pci/devices/0000:01:00.0' > Modules linked in: > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.14.0-rc5+ #50 > ----------------------------------------------------------------------------------------------------------------------------- > > >> Best regards, >> Liviu >> >> >>> pci_set_bus_of_node(child); >>> pci_set_bus_speed(child); >>> >>> Thanks, >>> Tanmay >>> >>> On Mon, Mar 3, 2014 at 9:33 AM, Liviu Dudau <Liviu.Dudau@xxxxxxx> wrote: >>> > pci_alloc_child_bus() uses the newly allocated child bus to figure >>> > out the domain number that is going to use for setting the device >>> > name. A better option is to use the parent bus domain number. >>> > >>> > Signed-off-by: Liviu Dudau <Liviu.Dudau@xxxxxxx> >>> > >>> > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c >>> > index 26237a0..a12cda5 100644 >>> > --- a/drivers/pci/probe.c >>> > +++ b/drivers/pci/probe.c >>> > @@ -677,7 +677,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, >>> > * now as the parent is not properly set up yet. >>> > */ >>> > child->dev.class = &pcibus_class; >>> > - dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr); >>> > + dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(parent), busnr); >>> > >>> > /* >>> > * Set up the primary, secondary and subordinate >>> > -- >>> > 1.9.0 >>> > >>> -- >>> 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 >>> >> >> -- >> ------------------- >> .oooO >> ( ) >> \ ( Oooo. >> \_) ( ) >> ) / >> (_/ >> >> One small step >> for me ... >> -- 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