On Mon, Jan 08, 2018 at 01:35:27PM -0500, Mikulas Patocka wrote: > > > On Mon, 8 Jan 2018, Lorenzo Pieralisi wrote: > > > On Fri, Jan 05, 2018 at 01:49:58PM -0500, Mikulas Patocka wrote: > > > > > > > > > On Fri, 5 Jan 2018, Lorenzo Pieralisi wrote: > > > > > > > On Tue, Jan 02, 2018 at 04:32:45PM -0500, Mikulas Patocka wrote: > > > > > Hi > > > > > > > > > > The patch 0e4c2eeb758a91e68b9eaf7a4bee9bd5ed97ff2b ("alpha/PCI: Replace > > > > > pci_fixup_irqs() call with host bridge IRQ mapping hooks") breaks > > > > > networking on Alpha for me. I have an Alpha Avanti server with tulip > > > > > network card. > > > > > > > > > > The patch 0e4c2eeb breaks it so that I get MCE when the network card > > > > > driver is loaded. The patch 814eae59 fixes the MCE, the system boot > > > > > completes, but the network card doesn't receive any interrupts (and soon > > > > > it reports warning about timeout on tx queue). All kernels in the 4.14 > > > > > branch have this bug. > > > > > > > > I reworked the patch, please let me know if it does fix the issue. > > > > > > > > Thanks, > > > > Lorenzo > > > > > > Networking doesn't work, other interrupts work. > > > > > > With this patch, /proc/interrupts shows one interrupt for the network card > > > (it used to be zero without this patch). > > > > It is getting harder to understand what's going on, here's an > > incremental patch with some logging, it would be ideal to add > > a similar logging with a working kernel so that we can actually > > compare the IRQ level registers programming, please test it > > when you have time. > > This patch works. The patch contains some small changes in the function > noname_map_irq compared to your previous patch and these changes make it > work. If I revert these changes, networking doesn't work. Yes - I am slowly understanding how this Alpha platform deals with IRQs, thank you for your help and apologies for the drawn-out fix, I just can't test on this platform. Patch below (minus pr_info that I will remove) should be the final one, please test it and provide me with logs so that I can check. Thank you very much. -- >8 -- diff --git a/arch/alpha/kernel/sys_sio.c b/arch/alpha/kernel/sys_sio.c index 37bd6d9b8eb9..754a890c8403 100644 --- a/arch/alpha/kernel/sys_sio.c +++ b/arch/alpha/kernel/sys_sio.c @@ -102,6 +102,15 @@ sio_pci_route(void) alpha_mv.sys.sio.route_tab); } +static bool sio_pci_dev_irq_needs_level(const struct pci_dev *dev) +{ + if ((dev->class >> 16 == PCI_BASE_CLASS_BRIDGE) && + (dev->class >> 8 != PCI_CLASS_BRIDGE_PCMCIA)) + return false; + + return true; +} + static unsigned int __init sio_collect_irq_levels(void) { @@ -110,8 +119,7 @@ sio_collect_irq_levels(void) /* Iterate through the devices, collecting IRQ levels. */ for_each_pci_dev(dev) { - if ((dev->class >> 16 == PCI_BASE_CLASS_BRIDGE) && - (dev->class >> 8 != PCI_CLASS_BRIDGE_PCMCIA)) + if (!sio_pci_dev_irq_needs_level(dev)) continue; if (dev->irq) @@ -120,8 +128,7 @@ sio_collect_irq_levels(void) return level_bits; } -static void __init -sio_fixup_irq_levels(unsigned int level_bits) +static void __sio_fixup_irq_levels(unsigned int level_bits, bool reset) { unsigned int old_level_bits; @@ -139,10 +146,21 @@ sio_fixup_irq_levels(unsigned int level_bits) */ old_level_bits = inb(0x4d0) | (inb(0x4d1) << 8); - level_bits |= (old_level_bits & 0x71ff); + if (reset) + old_level_bits &= 0x71ff; + + level_bits |= old_level_bits; outb((level_bits >> 0) & 0xff, 0x4d0); outb((level_bits >> 8) & 0xff, 0x4d1); + + pr_info("%s: level bits %x\n", __func__, level_bits); +} + +static inline void +sio_fixup_irq_levels(unsigned int level_bits) +{ + __sio_fixup_irq_levels(level_bits, true); } static inline int @@ -181,7 +199,14 @@ noname_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) const long min_idsel = 6, max_idsel = 14, irqs_per_slot = 5; int irq = COMMON_TABLE_LOOKUP, tmp; tmp = __kernel_extbl(alpha_mv.sys.sio.route_tab, irq); - return irq >= 0 ? tmp : -1; + + irq = irq >= 0 ? tmp : -1; + + /* Fixup IRQ level if an actual IRQ mapping is detected */ + if (sio_pci_dev_irq_needs_level(dev) && irq >= 0) + __sio_fixup_irq_levels(1 << irq, false); + + return irq; } static inline int -- 2.15.0 -- To unsubscribe from this list: send the line "unsubscribe linux-alpha" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html