From 3d5134ee8341bffc4f539049abb9e90d469b448d Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Mon, 4 Jun 2007 15:15:36 +1000 Subject: [POWERPC] Rewrite IO allocation & mapping on powerpc64 This rewrites pretty much from scratch the handling of MMIO and PIO space allocations on powerpc64. The main goals are: - Get rid of imalloc and use more common code where possible - Simplify the current mess so that PIO space is allocated and mapped in a single place for PCI bridges - Handle allocation constraints of PIO for all bridges including hot plugged ones within the 2GB space reserved for IO ports, so that devices on hotplugged busses will now work with drivers that assume IO ports fit in an int. - Cleanup and separate tracking of the ISA space in the reserved low 64K of IO space. No ISA -> Nothing mapped there. I booted a cell blade with IDE on PIO and MMIO and a dual G5 so far, that's it :-) With this patch, all allocations are done using the code in mm/vmalloc.c, though we use the low level __get_vm_area with explicit start/stop constraints in order to manage separate areas for vmalloc/vmap, ioremap, and PCI IOs. This greatly simplifies a lot of things, as you can see in the diffstat of that patch :-) A new pair of functions pcibios_map/unmap_io_space() now replace all of the previous code that used to manipulate PCI IOs space. The allocation is done at mapping time, which is now called from scan_phb's, just before the devices are probed (instead of after, which is by itself a bug fix). The only other caller is the PCI hotplug code for hot adding PCI-PCI bridges (slots). imalloc is gone, as is the "sub-allocation" thing, but I do beleive that hotplug should still work in the sense that the space allocation is always done by the PHB, but if you unmap a child bus of this PHB (which seems to be possible), then the code should properly tear down all the HPTE mappings for that area of the PHB allocated IO space. I now always reserve the first 64K of IO space for the bridge with the ISA bus on it. I have moved the code for tracking ISA in a separate file which should also make it smarter if we ever are capable of hot unplugging or re-plugging an ISA bridge. This should have a side effect on platforms like powermac where VGA IOs will no longer work. This is done on purpose though as they would have worked semi-randomly before. The idea at this point is to isolate drivers that might need to access those and fix them by providing a proper function to obtain an offset to the legacy IOs of a given bus. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras --- include/asm-powerpc/pci-bridge.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/asm-powerpc/pci-bridge.h') diff --git a/include/asm-powerpc/pci-bridge.h b/include/asm-powerpc/pci-bridge.h index c49ce41cfa95..5261527ed7b1 100644 --- a/include/asm-powerpc/pci-bridge.h +++ b/include/asm-powerpc/pci-bridge.h @@ -31,6 +31,7 @@ struct pci_controller { int last_busno; void __iomem *io_base_virt; + void *io_base_alloc; resource_size_t io_base_phys; /* Some machines have a non 1:1 mapping of @@ -167,6 +168,11 @@ static inline unsigned long pci_address_to_pio(phys_addr_t address) } #endif +extern void isa_bridge_find_early(struct pci_controller *hose); + +extern int pcibios_unmap_io_space(struct pci_bus *bus); +extern int pcibios_map_io_space(struct pci_bus *bus); + /* Return values for ppc_md.pci_probe_mode function */ #define PCI_PROBE_NONE -1 /* Don't look at this bus at all */ #define PCI_PROBE_NORMAL 0 /* Do normal PCI probing */ -- cgit v1.2.1