diff options
Diffstat (limited to 'arch/ia64/sn/pci')
| -rw-r--r-- | arch/ia64/sn/pci/pci_dma.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/arch/ia64/sn/pci/pci_dma.c b/arch/ia64/sn/pci/pci_dma.c index 0e4b9ad9ef02..abdf6eea6ac8 100644 --- a/arch/ia64/sn/pci/pci_dma.c +++ b/arch/ia64/sn/pci/pci_dma.c @@ -326,6 +326,29 @@ int sn_pci_legacy_read(struct pci_bus *bus, u16 port, u32 *val, u8 size) { unsigned long addr; int ret; + struct ia64_sal_retval isrv; + + /* + * First, try the SN_SAL_IOIF_PCI_SAFE SAL call which can work + * around hw issues at the pci bus level. SGI proms older than + * 4.10 don't implment this. + */ + + SAL_CALL(isrv, SN_SAL_IOIF_PCI_SAFE, + pci_domain_nr(bus), bus->number, + 0, /* io */ + 0, /* read */ + port, size, __pa(val)); + + if (isrv.status == 0) + return size; + + /* + * If the above failed, retry using the SAL_PROBE call which should + * be present in all proms (but which cannot work round PCI chipset + * bugs). This code is retained for compatability with old + * pre-4.10 proms, and should be removed at some point in the future. + */ if (!SN_PCIBUS_BUSSOFT(bus)) return -ENODEV; @@ -349,6 +372,29 @@ int sn_pci_legacy_write(struct pci_bus *bus, u16 port, u32 val, u8 size) int ret = size; unsigned long paddr; unsigned long *addr; + struct ia64_sal_retval isrv; + + /* + * First, try the SN_SAL_IOIF_PCI_SAFE SAL call which can work + * around hw issues at the pci bus level. SGI proms older than + * 4.10 don't implment this. + */ + + SAL_CALL(isrv, SN_SAL_IOIF_PCI_SAFE, + pci_domain_nr(bus), bus->number, + 0, /* io */ + 1, /* write */ + port, size, __pa(&val)); + + if (isrv.status == 0) + return size; + + /* + * If the above failed, retry using the SAL_PROBE call which should + * be present in all proms (but which cannot work round PCI chipset + * bugs). This code is retained for compatability with old + * pre-4.10 proms, and should be removed at some point in the future. + */ if (!SN_PCIBUS_BUSSOFT(bus)) { ret = -ENODEV; |