[PATCH v3 1/2] powerpc/PCI: move DMA & IRQ init to device_add() notification path
Benjamin Herrenschmidt
benh at kernel.crashing.org
Fri May 25 13:00:11 EST 2012
On Wed, 2012-05-23 at 16:37 -0600, Bjorn Helgaas wrote:
> From: Hiroo Matsumoto <matsumoto.hiroo at jp.fujitsu.com>
>
> PowerPC initialized DMA and IRQ information in the pci_scan_child_bus()
> -> pcibios_fixup_bus() path. Some hotplug drivers use that path, but
> others don't, e.g., pciehp, so sometimes hot-added devices are only
> partly initialized.
>
> This patch moves that initialization from pcibios_fixup_bus() to a new
> pci_bus_notify() called in the pci_bus_add_device() -> device_add() path.
> That means the initialization happens the same way for all PCI devices,
> whether they are present at boot or hot-added later.
>
> Note that powerpc was the only user of pci_fixup_cardbus(), which was
> used to do this same setup for cardbus devices. That's no longer
> needed because this setup will now be done in the same device_add()
> notification path as all other PCI devices.
Hrm. That will require a good deal of testing... Unfortunately I'm out
for a few weeks getting some surgery and then recovering...
Our PCI code has ancient roots and I wouldn't be surprised if that
change breaks subtle assumptions made here or there, we'd need to test
at least on a good range of macs and ibm hotplug stuff.
Cheers,
Ben.
> Typical failure of a hot-added e1000e device prior to this change:
>
> # echo 1 > /sys/bus/pci/slots/1/power
> <snip>
> e1000e 0000:03:00.0: enabling device (0000 -> 0002)
> e1000e 0000:03:00.0: No usable DMA configuration, aborting
> e1000e: probe of 0000:03:00.0 failed with error -5
>
> Successful initialization after this change:
>
> # echo 1 > /sys/bus/pci/slots/1/power
> <snip>
> e1000e 0000:03:00.0: enabling device (0000 -> 0002)
> irq: irq 6 on host /soc at ffe00000/msi at 41600 mapped to virtual irq 27
> e1000e 0000:03:00.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:15:17:bf:c0:c9
> e1000e 0000:03:00.0: eth0: Intel(R) PRO/1000 Network Connection
> e1000e 0000:03:00.0: eth0: MAC: 1, PHY: 4, PBA No: D50861-003
>
> [bhelgaas: changelog, notifier name, registration can be __init]
> CC: Dominik Brodowski <linux at dominikbrodowski.net>
> Signed-off-by: Hiroo MATSUMOTO <matsumoto.hiroo at jp.fujitsu.com>
> Signed-off-by: Bjorn Helgaas <bhelgaas at google.com>
> ---
> arch/powerpc/include/asm/pci.h | 2 -
> arch/powerpc/kernel/pci-common.c | 87 ++++++++++++++--------------
> arch/powerpc/kernel/pci_32.c | 2 +
> arch/powerpc/kernel/pci_64.c | 2 +
> arch/powerpc/kernel/pci_of_scan.c | 1
> arch/powerpc/platforms/pseries/pci_dlpar.c | 1
> drivers/pci/pci.c | 5 --
> drivers/pcmcia/cardbus.c | 3 -
> include/linux/pci.h | 3 -
> 9 files changed, 49 insertions(+), 57 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/pci.h b/arch/powerpc/include/asm/pci.h
> index 6653f27..d6a36a4 100644
> --- a/arch/powerpc/include/asm/pci.h
> +++ b/arch/powerpc/include/asm/pci.h
> @@ -183,10 +183,10 @@ extern void pci_resource_to_user(const struct pci_dev *dev, int bar,
> resource_size_t *start, resource_size_t *end);
>
> extern resource_size_t pcibios_io_space_offset(struct pci_controller *hose);
> -extern void pcibios_setup_bus_devices(struct pci_bus *bus);
> extern void pcibios_setup_bus_self(struct pci_bus *bus);
> extern void pcibios_setup_phb_io_space(struct pci_controller *hose);
> extern void pcibios_scan_phb(struct pci_controller *hose);
> +extern void pcibios_setup_bus_notifier(void);
>
> #endif /* __KERNEL__ */
> #endif /* __ASM_POWERPC_PCI_H */
> diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
> index 7320f36..41b39ba 100644
> --- a/arch/powerpc/kernel/pci-common.c
> +++ b/arch/powerpc/kernel/pci-common.c
> @@ -1009,40 +1009,6 @@ void __devinit pcibios_setup_bus_self(struct pci_bus *bus)
> ppc_md.pci_dma_bus_setup(bus);
> }
>
> -void __devinit pcibios_setup_bus_devices(struct pci_bus *bus)
> -{
> - struct pci_dev *dev;
> -
> - pr_debug("PCI: Fixup bus devices %d (%s)\n",
> - bus->number, bus->self ? pci_name(bus->self) : "PHB");
> -
> - list_for_each_entry(dev, &bus->devices, bus_list) {
> - /* Cardbus can call us to add new devices to a bus, so ignore
> - * those who are already fully discovered
> - */
> - if (dev->is_added)
> - continue;
> -
> - /* Fixup NUMA node as it may not be setup yet by the generic
> - * code and is needed by the DMA init
> - */
> - set_dev_node(&dev->dev, pcibus_to_node(dev->bus));
> -
> - /* Hook up default DMA ops */
> - set_dma_ops(&dev->dev, pci_dma_ops);
> - set_dma_offset(&dev->dev, PCI_DRAM_OFFSET);
> -
> - /* Additional platform DMA/iommu setup */
> - if (ppc_md.pci_dma_dev_setup)
> - ppc_md.pci_dma_dev_setup(dev);
> -
> - /* Read default IRQs and fixup if necessary */
> - pci_read_irq_line(dev);
> - if (ppc_md.pci_irq_fixup)
> - ppc_md.pci_irq_fixup(dev);
> - }
> -}
> -
> void pcibios_set_master(struct pci_dev *dev)
> {
> /* No special bus mastering setup handling */
> @@ -1059,19 +1025,9 @@ void __devinit pcibios_fixup_bus(struct pci_bus *bus)
>
> /* Now fixup the bus bus */
> pcibios_setup_bus_self(bus);
> -
> - /* Now fixup devices on that bus */
> - pcibios_setup_bus_devices(bus);
> }
> EXPORT_SYMBOL(pcibios_fixup_bus);
>
> -void __devinit pci_fixup_cardbus(struct pci_bus *bus)
> -{
> - /* Now fixup devices on that bus */
> - pcibios_setup_bus_devices(bus);
> -}
> -
> -
> static int skip_isa_ioresource_align(struct pci_dev *dev)
> {
> if (pci_has_flag(PCI_CAN_SKIP_ISA_ALIGN) &&
> @@ -1685,6 +1641,49 @@ void __devinit pcibios_scan_phb(struct pci_controller *hose)
> }
> }
>
> +static int pci_bus_notify(struct notifier_block *nb, unsigned long action,
> + void *data)
> +{
> + struct pci_dev *dev = to_pci_dev(data);
> +
> + switch (action) {
> + case BUS_NOTIFY_ADD_DEVICE:
> + /* Setup OF node pointer in the device */
> + dev->dev.of_node = pci_device_to_OF_node(dev);
> +
> + /* Fixup NUMA node as it may not be setup yet by the generic
> + * code and is needed by the DMA init
> + */
> + set_dev_node(&dev->dev, pcibus_to_node(dev->bus));
> +
> + /* Hook up default DMA ops */
> + set_dma_ops(&dev->dev, pci_dma_ops);
> + set_dma_offset(&dev->dev, PCI_DRAM_OFFSET);
> +
> + /* Additional platform DMA/iommu setup */
> + if (ppc_md.pci_dma_dev_setup)
> + ppc_md.pci_dma_dev_setup(dev);
> +
> + /* Read default IRQs and fixup if necessary */
> + pci_read_irq_line(dev);
> + if (ppc_md.pci_irq_fixup)
> + ppc_md.pci_irq_fixup(dev);
> +
> + break;
> + }
> +
> + return 0;
> +}
> +
> +static struct notifier_block device_nb = {
> + .notifier_call = pci_bus_notify,
> +};
> +
> +void __init pcibios_setup_bus_notifier(void)
> +{
> + bus_register_notifier(&pci_bus_type, &device_nb);
> +}
> +
> static void fixup_hide_host_resource_fsl(struct pci_dev *dev)
> {
> int i, class = dev->class >> 8;
> diff --git a/arch/powerpc/kernel/pci_32.c b/arch/powerpc/kernel/pci_32.c
> index 4b06ec5..640cc35 100644
> --- a/arch/powerpc/kernel/pci_32.c
> +++ b/arch/powerpc/kernel/pci_32.c
> @@ -231,6 +231,8 @@ static int __init pcibios_init(void)
>
> printk(KERN_INFO "PCI: Probing PCI hardware\n");
>
> + pcibios_setup_bus_notifier();
> +
> if (pci_has_flag(PCI_REASSIGN_ALL_BUS))
> pci_assign_all_buses = 1;
>
> diff --git a/arch/powerpc/kernel/pci_64.c b/arch/powerpc/kernel/pci_64.c
> index 4ff190f..8b212d3 100644
> --- a/arch/powerpc/kernel/pci_64.c
> +++ b/arch/powerpc/kernel/pci_64.c
> @@ -48,6 +48,8 @@ static int __init pcibios_init(void)
>
> printk(KERN_INFO "PCI: Probing PCI hardware\n");
>
> + pcibios_setup_bus_notifier();
> +
> /* For now, override phys_mem_access_prot. If we need it,g
> * later, we may move that initialization to each ppc_md
> */
> diff --git a/arch/powerpc/kernel/pci_of_scan.c b/arch/powerpc/kernel/pci_of_scan.c
> index ae5ea5e..eb09eca 100644
> --- a/arch/powerpc/kernel/pci_of_scan.c
> +++ b/arch/powerpc/kernel/pci_of_scan.c
> @@ -333,7 +333,6 @@ static void __devinit __of_scan_bus(struct device_node *node,
> */
> if (!rescan_existing)
> pcibios_setup_bus_self(bus);
> - pcibios_setup_bus_devices(bus);
>
> /* Now scan child busses */
> list_for_each_entry(dev, &bus->devices, bus_list) {
> diff --git a/arch/powerpc/platforms/pseries/pci_dlpar.c b/arch/powerpc/platforms/pseries/pci_dlpar.c
> index 3ccebc8..0b1b6b3 100644
> --- a/arch/powerpc/platforms/pseries/pci_dlpar.c
> +++ b/arch/powerpc/platforms/pseries/pci_dlpar.c
> @@ -120,7 +120,6 @@ void pcibios_add_pci_devices(struct pci_bus * bus)
> num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
> if (!num)
> return;
> - pcibios_setup_bus_devices(bus);
> max = bus->busn_res.start;
> for (pass=0; pass < 2; pass++)
> list_for_each_entry(dev, &bus->devices, bus_list) {
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 15d442a..43e0a4f 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -3789,11 +3789,6 @@ int __attribute__ ((weak)) pci_ext_cfg_avail(struct pci_dev *dev)
> return 1;
> }
>
> -void __weak pci_fixup_cardbus(struct pci_bus *bus)
> -{
> -}
> -EXPORT_SYMBOL(pci_fixup_cardbus);
> -
> static int __init pci_setup(char *str)
> {
> while (str) {
> diff --git a/drivers/pcmcia/cardbus.c b/drivers/pcmcia/cardbus.c
> index 24caeaf..a980691 100644
> --- a/drivers/pcmcia/cardbus.c
> +++ b/drivers/pcmcia/cardbus.c
> @@ -71,7 +71,6 @@ int __ref cb_alloc(struct pcmcia_socket *s)
> unsigned int max, pass;
>
> s->functions = pci_scan_slot(bus, PCI_DEVFN(0, 0));
> - pci_fixup_cardbus(bus);
>
> max = bus->busn_res.start;
> for (pass = 0; pass < 2; pass++)
> @@ -85,7 +84,6 @@ int __ref cb_alloc(struct pcmcia_socket *s)
> */
> pci_bus_size_bridges(bus);
> pci_bus_assign_resources(bus);
> - cardbus_config_irq_and_cls(bus, s->pci_irq);
>
> /* socket specific tune function */
> if (s->tune_bridge)
> @@ -93,6 +91,7 @@ int __ref cb_alloc(struct pcmcia_socket *s)
>
> pci_enable_bridges(bus);
> pci_bus_add_devices(bus);
> + cardbus_config_irq_and_cls(bus, s->pci_irq);
>
> return 0;
> }
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index a0e2d7f..3924c02 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -651,9 +651,6 @@ resource_size_t pcibios_align_resource(void *, const struct resource *,
> resource_size_t);
> void pcibios_update_irq(struct pci_dev *, int irq);
>
> -/* Weak but can be overriden by arch */
> -void pci_fixup_cardbus(struct pci_bus *);
> -
> /* Generic PCI functions used internally */
>
> void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
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