[RFC 2/4] PCI: generic: Add support for ARM64 and MSI(x)
From: arnd@arndb.de (Arnd Bergmann)
Date: 2014-09-30 20:01:28
Also in:
linux-devicetree, linux-pci, lkml
Subsystem:
arm port, pci subsystem, the rest · Maintainers:
Russell King, Bjorn Helgaas, Linus Torvalds
On Tuesday 30 September 2014 20:54:41 Arnd Bergmann wrote:
On Tuesday 30 September 2014 18:48:21 Liviu Dudau wrote:quoted
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These are the functions I found that refer to pci_sys_data on arm32: pcibios_add_bus pcibios_remove_busThese are only needed if you want to do per HB processing of the busquoted
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pcibios_align_resourcemvebu is the only user of this function.quoted
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pci_mmap_page_rangeThis is only needed when mapping a PCI resource to userspace. Is that your case here?quoted
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pci_domain_nr pci_proc_domainWe have equivalent functionality in the generic patches for those.We clearly don't need those functions for the new drivers, but that's not the point. The problem is that when you build a kernel that has both a traditional host bridge driver and a new one in it, you always get those functions and they get called from the PCI core, with incorrect arguments.
FWIW, the last time we discussed this, I think I had suggested that the functions that are currently architecture specific and have a generic __weak fallback could become function pointers in a per-host structure passed to pci_scan_root_bus, either a new structure or an extended struct pci_ops. Something along these lines:
diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h
index 7fc42784becb..3da32fc631d0 100644
--- a/arch/arm/include/asm/mach/pci.h
+++ b/arch/arm/include/asm/mach/pci.h@@ -36,7 +36,6 @@ struct hw_pci { resource_size_t start, resource_size_t size, resource_size_t align); - void (*add_bus)(struct pci_bus *bus); void (*remove_bus)(struct pci_bus *bus); };
@@ -65,7 +64,6 @@ struct pci_sys_data { resource_size_t start, resource_size_t size, resource_size_t align); - void (*add_bus)(struct pci_bus *bus); void (*remove_bus)(struct pci_bus *bus); void *private_data; /* platform controller private data */ };
diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
index 17a26c17f7f5..3cbcf8dc41e4 100644
--- a/arch/arm/kernel/bios32.c
+++ b/arch/arm/kernel/bios32.c@@ -360,13 +360,6 @@ void pcibios_fixup_bus(struct pci_bus *bus) } EXPORT_SYMBOL(pcibios_fixup_bus); -void pcibios_add_bus(struct pci_bus *bus) -{ - struct pci_sys_data *sys = bus->sysdata; - if (sys->add_bus) - sys->add_bus(bus); -} - void pcibios_remove_bus(struct pci_bus *bus) { struct pci_sys_data *sys = bus->sysdata;
@@ -475,7 +468,6 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw, sys->swizzle = hw->swizzle; sys->map_irq = hw->map_irq; sys->align_resource = hw->align_resource; - sys->add_bus = hw->add_bus; sys->remove_bus = hw->remove_bus; INIT_LIST_HEAD(&sys->resources);
diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
index b1315e197ffb..c9a0ee0429e8 100644
--- a/drivers/pci/host/pci-mvebu.c
+++ b/drivers/pci/host/pci-mvebu.c@@ -716,6 +716,7 @@ static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where, static struct pci_ops mvebu_pcie_ops = { .read = mvebu_pcie_rd_conf, .write = mvebu_pcie_wr_conf, + .add_bus = mvebu_pcie_add_bus, }; static int mvebu_pcie_setup(int nr, struct pci_sys_data *sys)
@@ -823,7 +824,6 @@ static void mvebu_pcie_enable(struct mvebu_pcie *pcie) hw.map_irq = of_irq_parse_and_map_pci; hw.ops = &mvebu_pcie_ops; hw.align_resource = mvebu_pcie_align_resource; - hw.add_bus = mvebu_pcie_add_bus; pci_common_init(&hw); }
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index a63a47a70846..be6d56358320 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c@@ -1885,6 +1885,8 @@ int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge) void __weak pcibios_add_bus(struct pci_bus *bus) { + if (bus->ops && bus->ops->add_bus) + bus->ops->add_bus(bus); } void __weak pcibios_remove_bus(struct pci_bus *bus)
Arnd