The pci_fixup_irqs() function allocates IRQs for all PCI devices present in
a system; those PCI devices possibly belong to different PCI bus trees (and
possibly rooted at different host bridges) and may well be enabled (ie
probed and bound to a driver) by the time pci_fixup_irqs() is called when
probing a given host bridge driver.
Furthermore, current kernel code relying on pci_fixup_irqs() to assign
legacy PCI IRQs to devices does not work at all for hotplugged devices in
that the code carrying out the IRQ fixup is called at host bridge driver
probe time, which just cannot take into account devices hotplugged after
the system has booted.
The introduction of map/swizzle function hooks in struct pci_host_bridge
allows us to define per-bridge map/swizzle functions, that can be used at
device probe time in PCI core code to allocate IRQs for a given device
(through pci_assign_irq()).
Convert PCI host bridge initialization code to the
pci_scan_root_bus_bridge() API (that allows to pass a struct
pci_host_bridge with initialized map/swizzle pointers) and remove the
pci_fixup_irqs() call from arch code.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
If pci_scan_root_bus() fails (ie returns NULL) pcibios_scan_bus() must
return immediately since the struct pci_bus pointer it returns is not valid
and cannot be used.
Move code checking the pci_scan_root_bus() return value to reinstate proper
pcibios_scanbus() error path behaviour.
Fixes: 88555b4819 ("MIPS: PCI: Support for CONFIG_PCI_DOMAINS_GENERIC")
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
pci_add_resource_offset() is for host bridge windows where the bridge
translates CPU addresses to PCI bus addresses by adding an offset. To my
knowledge, no host bridge translates bus numbers, so this is only useful
for MEM and IO windows. In any event, host->busn_offset is never set to
anything other than zero, so pci_add_resource() is sufficient.
a2e50f53d5 ("MIPS: PCI: Add a hook for IORESOURCE_BUS in
pci_controller/bridge_controller") also added busn_resource itself. This
is currently unused but may be used by future SGI IP27 fixes, so I left it
there.
Tested-by: Joshua Kinard <kumba@gentoo.org> # SGI IP30 and IP27
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Joshua Kinard <kumba@gentoo.org>
With commit 23dac14d05 ("MIPS: PCI: Use struct list_head lists") new
controllers are added after the specified head where they where added
before the specified head previously.
Use list_add_tail to restore the former order.
This patches fixes the following PCI error on lantiq:
pci 0000:01:00.0: BAR 0: error updating (0x1c000004 != 0x000000)
Fixes: 23dac14d05 ("MIPS: PCI: Use struct list_head lists")
Signed-off-by: Mathias Kresin <dev@kresin.me>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15808/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Split out the parts of pci.c that are used by existing systems with
MIPS-style PCI drivers but that will not be used by systems with more
generic PCI drivers such as pcie-xilinx. This is done in preparation for
allowing configurations where the code moved to pci-legacy.c is not
built.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Paul Burton <paul.burton@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/14344/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>