| Message ID | 20170702211950.GD18324@bhelgaas-glaptop.roam.corp.google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Sun, Jul 02, 2017 at 04:19:50PM -0500, Bjorn Helgaas wrote: > On Sat, Jul 01, 2017 at 03:06:30PM +0100, Lorenzo Pieralisi wrote: > > Hi Bjorn, > > > > On Thu, Jun 08, 2017 at 03:13:29PM +0100, Lorenzo Pieralisi wrote: > > > Legacy PCI host controllers (ie host controllers that set-up the PCI bus > > > through the ARM pci_common_init() API) are currently relying on > > > pci_fixup_irqs() to assign legacy PCI irqs to devices. This is not ideal > > > in that pci_fixup_irqs() assign IRQs for all PCI devices present in a > > > given system some of which may well be enabled by the time > > > pci_fixup_irqs() is called (ie a system with multiple host controllers). > > > With the introduction of struct pci_host_bridge.(*map_irq) pointer it is > > > possible to assign IRQs for all devices originating from a PCI host > > > bridge at probe time; this is implemented through pci_assign_irq() that > > > relies on the struct pci_host_bridge.map_irq pointer to map IRQ for a > > > given device. > > > > > > The benefits this brings are twofold: > > > > > > - the IRQ for a device is assigned once at probe time > > > - the IRQ assignment works also for hotplugged devices > > > > > > Remove pci_fixup_irqs() call from bios32 code and rely on > > > pci_assign_irq() to carry out the IRQ mapping at device probe > > > time. > > > > > > The map_irq() and swizzle_irq() struct pci_host_bridge callbacks are > > > set-up in the struct pci_host_bridge created in the bios32 > > > pcibios_init_hw() function and mach-* code paths (for PCI mach > > > implementations that require a specific struct hw_pci.(*scan) function > > > callback). > > > > > > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > > > Cc: Jason Cooper <jason@lakedaemon.net> > > > Cc: Bjorn Helgaas <bhelgaas@google.com> > > > Cc: Russell King <linux@armlinux.org.uk> > > > Cc: Andrew Lunn <andrew@lunn.ch> > > > --- > > > arch/arm/kernel/bios32.c | 4 ++-- > > > arch/arm/mach-dove/pcie.c | 18 ++++++++++-------- > > > arch/arm/mach-iop13xx/pci.c | 2 ++ > > > arch/arm/mach-orion5x/pci.c | 28 +++++++++++++++------------- > > > 4 files changed, 29 insertions(+), 23 deletions(-) > > > > As I mentioned to you, this patch is incomplete and needs an upgrade > > (ie I misread how Orion and the gazillions board file that go with > > it to map irqs - apologies but it is very hard to untangle). > > > > I am inlining below an incremental patch to be folded in commit: > > > > feaec00e757a ("ARM/PCI: Remove pci_fixup_irqs() call for bios32 host > > controllers") > > > > in your pci/irq-fixups branch, or if you prefer I can send you the > > resulting squashed-in patch to replace this one, as you prefer. > > Thanks, I folded this into pci/irq-fixups. The resulting patch is > merely this: Yes that's what I expected, we remove pci_fixup_irqs() and add the hooks into the host bridge structure that should cover all host bridges initialized via pci_common_init_dev(). Thanks ! Lorenzo > commit 16508469c0f3198a63923aaec08efa1c63f5fbcc > Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Date: Wed Jun 28 15:14:04 2017 -0500 > > ARM/PCI: Remove pci_fixup_irqs() call for bios32 host controllers > > Legacy PCI host controllers (ie host controllers that set-up the PCI bus > through the ARM pci_common_init() API) are currently relying on > pci_fixup_irqs() to assign legacy PCI irqs to devices. This is not ideal > in that pci_fixup_irqs() assigns IRQs for all PCI devices present in a given > system some of which may well be enabled by the time pci_fixup_irqs() is > called (ie a system with multiple host controllers). With the introduction > of struct pci_host_bridge.(*map_irq) pointer it is possible to assign IRQs > for all devices originating from a PCI host bridge at probe time; this is > implemented through pci_assign_irq() that relies on the struct > pci_host_bridge.map_irq pointer to map IRQ for a given device. > > The benefits this brings are twofold: > > - the IRQ for a device is assigned once at probe time > - the IRQ assignment works also for hotplugged devices > > Remove pci_fixup_irqs() call from bios32 code and rely on pci_assign_irq() > to carry out the IRQ mapping at device probe time. > > The map_irq() and swizzle_irq() struct pci_host_bridge callbacks are set-up > in the struct pci_host_bridge created in the bios32 pcibios_init_hw() > function and mach-* code paths (for PCI mach implementations that require a > specific struct hw_pci.(*scan) function callback). > > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > [bhelgaas: folded in fixes from Lorenzo: > http://lkml.kernel.org/r/20170701140629.GC8977@red-moon] > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> > Cc: Jason Cooper <jason@lakedaemon.net> > Cc: Russell King <linux@armlinux.org.uk> > Cc: Andrew Lunn <andrew@lunn.ch> > > diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c > index 4c7621ac389c..56dc1a3a33b4 100644 > --- a/arch/arm/kernel/bios32.c > +++ b/arch/arm/kernel/bios32.c > @@ -484,6 +484,9 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw, > break; > } > > + bridge->map_irq = pcibios_map_irq; > + bridge->swizzle_irq = pcibios_swizzle; > + > if (hw->scan) > ret = hw->scan(nr, bridge); > else { > @@ -530,8 +533,6 @@ void pci_common_init_dev(struct device *parent, struct hw_pci *hw) > if (hw->postinit) > hw->postinit(); > > - pci_fixup_irqs(pcibios_swizzle, pcibios_map_irq); > - > list_for_each_entry(sys, &head, node) { > struct pci_bus *bus = sys->bus; >
diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c index 4c7621ac389c..56dc1a3a33b4 100644 --- a/arch/arm/kernel/bios32.c +++ b/arch/arm/kernel/bios32.c @@ -484,6 +484,9 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw, break; } + bridge->map_irq = pcibios_map_irq; + bridge->swizzle_irq = pcibios_swizzle; + if (hw->scan) ret = hw->scan(nr, bridge); else { @@ -530,8 +533,6 @@ void pci_common_init_dev(struct device *parent, struct hw_pci *hw) if (hw->postinit) hw->postinit(); - pci_fixup_irqs(pcibios_swizzle, pcibios_map_irq); - list_for_each_entry(sys, &head, node) { struct pci_bus *bus = sys->bus;