SEO

We have some serious problems with enabling io and/or mem space
decoding on pci devices where we shouldn't. We have seen this with
pci bridge devices that weren't properly initialized by the firmware,
but we have some evidence that vga legacy decodings are giving is
problems too. The attached patch is a possible way to fix this, but
might cause problems for people. To assess the impact we need to test
this patch on as many systems as possible. If you see any changes in
your dmesg, please mail me the before and after dmesg. Please also do
this if your machine starts printing "enabling io space" or "enabling
mem space" in dmesg.

Thanks,

Mark

Index: pci.c
================================================== =================
RCS file: /cvs/src/sys/dev/pci/pci.c,v
retrieving revision 1.45
diff -u -p -r1.45 pci.c
- --- pci.c 22 Mar 2006 00:36:03 -0000 1.45
+++ pci.c 26 Jun 2006 17:52:52 -0000
@@ -233,6 +233,7 @@ pcisubmatch(struct device *parent, void

success = (*cf->cf_attach->ca_match)(parent, match, aux);

+#if 0
/*
* My Dell BIOS does not enable certain non-critical PCI devices
* for IO and memory cycles (e.g. network card). This is
@@ -247,6 +248,7 @@ pcisubmatch(struct device *parent, void
csr | PCI_COMMAND_MASTER_ENABLE |
PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE);
}
+#endif

return (success);
}
Index: pci_map.c
================================================== =================
RCS file: /cvs/src/sys/dev/pci/pci_map.c,v
retrieving revision 1.16
diff -u -p -r1.16 pci_map.c
- --- pci_map.c 31 May 2006 08:58:05 -0000 1.16
+++ pci_map.c 26 Jun 2006 17:52:52 -0000
@@ -306,8 +306,21 @@ pci_mapreg_map(struct pci_attach_args *p
bus_space_handle_t handle;
bus_addr_t base;
bus_size_t size;
+ pcireg_t csr;
int flags;
int rv;
+
+ csr = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
+ if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO) {
+ if ((csr & PCI_COMMAND_IO_ENABLE) == 0)
+ printf(": enabling io space");
+ csr |= PCI_COMMAND_IO_ENABLE;
+ } else {
+ if ((csr & PCI_COMMAND_MEM_ENABLE) == 0)
+ printf(": enabling mem space");
+ csr |= PCI_COMMAND_MEM_ENABLE;
+ }
+ pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG, csr);

if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO) {
if ((pa->pa_flags & PCI_FLAGS_IO_ENABLED) == 0)