[RFC/PATCH 3/6] powerpc: pci32: Remove PowerMac P2P bridge IO hack
Benjamin Herrenschmidt
benh at kernel.crashing.org
Wed Dec 5 11:53:02 EST 2007
The 32 bits PowerPC PCI code has a hack for use by some PowerMacs
to try to re-open PCI<->PCI bridge IO resources that were closed
by the firmware. This is no longer necessary as the generic code
will now do that for us.
Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
---
arch/powerpc/kernel/pci_32.c | 215 -------------------------------------------
1 file changed, 1 insertion(+), 214 deletions(-)
Index: linux-work/arch/powerpc/kernel/pci_32.c
===================================================================
--- linux-work.orig/arch/powerpc/kernel/pci_32.c 2007-12-04 17:02:13.000000000 +1100
+++ linux-work/arch/powerpc/kernel/pci_32.c 2007-12-04 17:02:31.000000000 +1100
@@ -711,217 +711,6 @@ void pcibios_make_OF_bus_map(void)
}
#endif /* CONFIG_PPC_OF */
-#ifdef CONFIG_PPC_PMAC
-/*
- * This set of routines checks for PCI<->PCI bridges that have closed
- * IO resources and have child devices. It tries to re-open an IO
- * window on them.
- *
- * This is a _temporary_ fix to workaround a problem with Apple's OF
- * closing IO windows on P2P bridges when the OF drivers of cards
- * below this bridge don't claim any IO range (typically ATI or
- * Adaptec).
- *
- * A more complete fix would be to use drivers/pci/setup-bus.c, which
- * involves a working pcibios_fixup_pbus_ranges(), some more care about
- * ordering when creating the host bus resources, and maybe a few more
- * minor tweaks
- */
-
-/* Initialize bridges with base/limit values we have collected */
-static void __init
-do_update_p2p_io_resource(struct pci_bus *bus, int enable_vga)
-{
- struct pci_dev *bridge = bus->self;
- struct pci_controller* hose = (struct pci_controller *)bridge->sysdata;
- u32 l;
- u16 w;
- struct resource res;
-
- if (bus->resource[0] == NULL)
- return;
- res = *(bus->resource[0]);
-
- DBG("Remapping Bus %d, bridge: %s\n", bus->number, pci_name(bridge));
- res.start -= ((unsigned long) hose->io_base_virt - isa_io_base);
- res.end -= ((unsigned long) hose->io_base_virt - isa_io_base);
- DBG(" IO window: %016llx-%016llx\n", res.start, res.end);
-
- /* Set up the top and bottom of the PCI I/O segment for this bus. */
- pci_read_config_dword(bridge, PCI_IO_BASE, &l);
- l &= 0xffff000f;
- l |= (res.start >> 8) & 0x00f0;
- l |= res.end & 0xf000;
- pci_write_config_dword(bridge, PCI_IO_BASE, l);
-
- if ((l & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
- l = (res.start >> 16) | (res.end & 0xffff0000);
- pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, l);
- }
-
- pci_read_config_word(bridge, PCI_COMMAND, &w);
- w |= PCI_COMMAND_IO;
- pci_write_config_word(bridge, PCI_COMMAND, w);
-
-#if 0 /* Enabling this causes XFree 4.2.0 to hang during PCI probe */
- if (enable_vga) {
- pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, &w);
- w |= PCI_BRIDGE_CTL_VGA;
- pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, w);
- }
-#endif
-}
-
-/* This function is pretty basic and actually quite broken for the
- * general case, it's enough for us right now though. It's supposed
- * to tell us if we need to open an IO range at all or not and what
- * size.
- */
-static int __init
-check_for_io_childs(struct pci_bus *bus, struct resource* res, int *found_vga)
-{
- struct pci_dev *dev;
- int i;
- int rc = 0;
-
-#define push_end(res, mask) do { \
- BUG_ON((mask+1) & mask); \
- res->end = (res->end + mask) | mask; \
-} while (0)
-
- list_for_each_entry(dev, &bus->devices, bus_list) {
- u16 class = dev->class >> 8;
-
- if (class == PCI_CLASS_DISPLAY_VGA ||
- class == PCI_CLASS_NOT_DEFINED_VGA)
- *found_vga = 1;
- if (class >> 8 == PCI_BASE_CLASS_BRIDGE && dev->subordinate)
- rc |= check_for_io_childs(dev->subordinate, res, found_vga);
- if (class == PCI_CLASS_BRIDGE_CARDBUS)
- push_end(res, 0xfff);
-
- for (i=0; i<PCI_NUM_RESOURCES; i++) {
- struct resource *r;
- unsigned long r_size;
-
- if (dev->class >> 8 == PCI_CLASS_BRIDGE_PCI
- && i >= PCI_BRIDGE_RESOURCES)
- continue;
- r = &dev->resource[i];
- r_size = r->end - r->start;
- if (r_size < 0xfff)
- r_size = 0xfff;
- if (r->flags & IORESOURCE_IO && (r_size) != 0) {
- rc = 1;
- push_end(res, r_size);
- }
- }
- }
-
- return rc;
-}
-
-/* Here we scan all P2P bridges of a given level that have a closed
- * IO window. Note that the test for the presence of a VGA card should
- * be improved to take into account already configured P2P bridges,
- * currently, we don't see them and might end up configuring 2 bridges
- * with VGA pass through enabled
- */
-static void __init
-do_fixup_p2p_level(struct pci_bus *bus)
-{
- struct pci_bus *b;
- int i, parent_io;
- int has_vga = 0;
-
- for (parent_io=0; parent_io<4; parent_io++)
- if (bus->resource[parent_io]
- && bus->resource[parent_io]->flags & IORESOURCE_IO)
- break;
- if (parent_io >= 4)
- return;
-
- list_for_each_entry(b, &bus->children, node) {
- struct pci_dev *d = b->self;
- struct pci_controller* hose = (struct pci_controller *)d->sysdata;
- struct resource *res = b->resource[0];
- struct resource tmp_res;
- unsigned long max;
- int found_vga = 0;
-
- memset(&tmp_res, 0, sizeof(tmp_res));
- tmp_res.start = bus->resource[parent_io]->start;
-
- /* We don't let low addresses go through that closed P2P bridge, well,
- * that may not be necessary but I feel safer that way
- */
- if (tmp_res.start == 0)
- tmp_res.start = 0x1000;
-
- if (!list_empty(&b->devices) && res && res->flags == 0 &&
- res != bus->resource[parent_io] &&
- (d->class >> 8) == PCI_CLASS_BRIDGE_PCI &&
- check_for_io_childs(b, &tmp_res, &found_vga)) {
- u8 io_base_lo;
-
- printk(KERN_INFO "Fixing up IO bus %s\n", b->name);
-
- if (found_vga) {
- if (has_vga) {
- printk(KERN_WARNING "Skipping VGA, already active"
- " on bus segment\n");
- found_vga = 0;
- } else
- has_vga = 1;
- }
- pci_read_config_byte(d, PCI_IO_BASE, &io_base_lo);
-
- if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32)
- max = ((unsigned long) hose->io_base_virt
- - isa_io_base) + 0xffffffff;
- else
- max = ((unsigned long) hose->io_base_virt
- - isa_io_base) + 0xffff;
-
- *res = tmp_res;
- res->flags = IORESOURCE_IO;
- res->name = b->name;
-
- /* Find a resource in the parent where we can allocate */
- for (i = 0 ; i < 4; i++) {
- struct resource *r = bus->resource[i];
- if (!r)
- continue;
- if ((r->flags & IORESOURCE_IO) == 0)
- continue;
- DBG("Trying to allocate from %016llx, size %016llx from parent"
- " res %d: %016llx -> %016llx\n",
- res->start, res->end, i, r->start, r->end);
-
- if (allocate_resource(r, res, res->end + 1, res->start, max,
- res->end + 1, NULL, NULL) < 0) {
- DBG("Failed !\n");
- continue;
- }
- do_update_p2p_io_resource(b, found_vga);
- break;
- }
- }
- do_fixup_p2p_level(b);
- }
-}
-
-static void
-pcibios_fixup_p2p_bridges(void)
-{
- struct pci_bus *b;
-
- list_for_each_entry(b, &pci_root_buses, node)
- do_fixup_p2p_level(b);
-}
-
-#endif /* CONFIG_PPC_PMAC */
-
static int __init
pcibios_init(void)
{
@@ -961,9 +750,7 @@ pcibios_init(void)
pcibios_allocate_bus_resources(&pci_root_buses);
pcibios_allocate_resources(0);
pcibios_allocate_resources(1);
-#ifdef CONFIG_PPC_PMAC
- pcibios_fixup_p2p_bridges();
-#endif /* CONFIG_PPC_PMAC */
+
DBG("PCI: Assigning unassigned resouces...\n");
pci_assign_unassigned_resources();
More information about the Linuxppc-dev
mailing list