On Sun, Jul 26, 2015 at 07:43:46PM +0100, Jayachandran C. wrote: > On Sun, Jul 26, 2015 at 07:16:46PM +0100, Lorenzo Pieralisi wrote: > > On Sun, Jul 26, 2015 at 04:25:29PM +0100, Jayachandran C. wrote: > > > On Fri, Jul 24, 2015 at 05:13:03PM +0100, Lorenzo Pieralisi wrote: > > > > On ARM PCI systems relying on the pcibios API to initialize PCI host > > > > controllers, the pcibios_msi_controller weak callback is used to look-up > > > > the msi_controller pointer, through pci_sys_data msi_ctrl pointer. > > > > > > > > pci_sys_data is an ARM specific structure, which prevents using the > > > > same mechanism (so same PCI host controller drivers) on ARM64 systems. > > > > > > > > Since the struct pci_bus already contains an msi_controller pointer and > > > > the kernel already uses it to look-up the msi controller, > > > > this patch converts ARM host controller and related pcibios/host bridges > > > > initialization routines so that the msi_controller pointer look-up can be > > > > carried out by PCI core code through the struct pci_bus msi pointer, > > > > removing the need for the arch specific pcibios_msi_controller callback > > > > and the related pci_sys_data msi_ctrl pointer. > > > > > > > > ARM is the only arch relying on the pcibios_msi_controller() weak > > > > function, hence this patch removes the default weak implementation > > > > from PCI core code since it becomes of no use. > > > > > > > > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > > > > Acked-by: Marc Zyngier <marc.zyngier@xxxxxxx> > > > > Cc: Pratyush Anand <pratyush.anand@xxxxxxxxx> > > > > Cc: Arnd Bergmann <arnd@xxxxxxxx> > > > > Cc: Jingoo Han <jingoohan1@xxxxxxxxx> > > > > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > > > > Cc: Simon Horman <horms@xxxxxxxxxxxx> > > > > Cc: Russell King <linux@xxxxxxxxxxxxxxxx> > > > > Cc: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> > > > > Cc: Thierry Reding <thierry.reding@xxxxxxxxx> > > > > Cc: Michal Simek <michal.simek@xxxxxxxxxx> > > > > Cc: Marc Zyngier <marc.zyngier@xxxxxxx> > > > > --- > > > > v1->v2 > > > > > > > > - Added patch to replace panic statements with WARN > > > > - Removed unused pcibios_msi_controller() and pci_msi_controller() from > > > > core code > > > > - Dropped RFT status > > > > > > > > v1: http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/356028.html > > > > > > > > arch/arm/include/asm/mach/pci.h | 3 --- > > > > arch/arm/kernel/bios32.c | 29 +++++++++++++---------------- > > > > drivers/pci/host/pcie-designware.c | 9 +++++++-- > > > > drivers/pci/host/pcie-xilinx.c | 12 ++++++++++-- > > > > drivers/pci/msi.c | 17 +---------------- > > > > 5 files changed, 31 insertions(+), 39 deletions(-) > > > > > > > [...] > > > > diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c > > > > index f66be86..0d20142 100644 > > > > --- a/drivers/pci/msi.c > > > > +++ b/drivers/pci/msi.c > > > > @@ -77,24 +77,9 @@ static void pci_msi_teardown_msi_irqs(struct pci_dev *dev) > > > > > > > > /* Arch hooks */ > > > > > > > > -struct msi_controller * __weak pcibios_msi_controller(struct pci_dev *dev) > > > > -{ > > > > - return NULL; > > > > -} > > > > - > > > > -static struct msi_controller *pci_msi_controller(struct pci_dev *dev) > > > > -{ > > > > - struct msi_controller *msi_ctrl = dev->bus->msi; > > > > - > > > > - if (msi_ctrl) > > > > - return msi_ctrl; > > > > - > > > > - return pcibios_msi_controller(dev); > > > > -} > > > > - > > > > int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc) > > > > { > > > > - struct msi_controller *chip = pci_msi_controller(dev); > > > > + struct msi_controller *chip = dev->bus->msi; > > > > int err; > > > > > > > > if (!chip || !chip->setup_irq) > > > > > > Don't you have to go to the top level bus and get the ->msi pointer? Something > > > like: > > > > > > for (bus = dev->bus; bus != NULL; bus = bus->parent) > > > if (bus->msi) > > > return bus->msi; > > > > > > I have not been following this closely, so I may have missed some patches. > > > > The msi pointer is initialized from parent to child in > > pci_alloc_child_bus(), so PCI core does that for us, > > that's my understanding. > > > > It works the same as sysdata pointer, which is why > > pcibios_msi_controller works in the current kernel. > > Thanks. > > > On a side note, are you able to prepare a new version > > of your set to enable the PCI generic host on ARM64 > > (and remove pci_sys_data and related ifdef CONFIG_ARM > > from it) ? > > > > We are not far from removing the pci_sys_data dependency, > > if you can't prepare a new version of your series let me > > know I can do it on your behalf. > > I will post an updated patch with a minor fix. I will also > add a patch for parsing msi-parent and setting ->msi on > the root bus. There is no need for any msi parsing in the PCI generic host, Marc implemented mechanism for us in core code: https://lkml.org/lkml/2015/7/7/724 Thanks, Lorenzo -- 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
