/* When a PCI device is isolated from the bus, a subsequent MMIO read is
* required for the kernel EEH mechanisms to notice. As the Solarflare driver
* was written to minimise MMIO read (for latency) then a periodic call to check
* the EEH status of the device is required so that device recovery can happen
* in a timely fashion.
*/
static void siena_monitor(struct efx_nic *efx)
{
struct pci_dev *pcidev = efx->pci_dev;
struct device_node *dn = pci_device_to_OF_node(pcidev);
eeh_dn_check_failure(dn, pcidev);
}
int rtas_read_config(struct pci_dn *pdn, int where, int size, u32 *val)
{
int returnval = -1;
unsigned long buid, addr;
int ret;
if (!pdn)
return PCIBIOS_DEVICE_NOT_FOUND;
if (!config_access_valid(pdn, where))
return PCIBIOS_BAD_REGISTER_NUMBER;
addr = rtas_config_addr(pdn->busno, pdn->devfn, where);
buid = pdn->phb->buid;
if (buid) {
ret = rtas_call(ibm_read_pci_config, 4, 2, &returnval,
addr, BUID_HI(buid), BUID_LO(buid), size);
} else {
ret = rtas_call(read_pci_config, 2, 2, &returnval, addr, size);
}
*val = returnval;
if (ret)
return PCIBIOS_DEVICE_NOT_FOUND;
if (returnval == EEH_IO_ERROR_VALUE(size) &&
eeh_dn_check_failure (pdn->node, NULL))
return PCIBIOS_DEVICE_NOT_FOUND;
return PCIBIOS_SUCCESSFUL;
}
/**
* eeh_check_failure - check if all 1's data is due to EEH slot freeze
* @token i/o token, should be address in the form 0xA....
* @val value, should be all 1's (XXX why do we need this arg??)
*
* Check for an EEH failure at the given token address. Call this
* routine if the result of a read was all 0xff's and you want to
* find out if this is due to an EEH slot freeze event. This routine
* will query firmware for the EEH status.
*
* Note this routine is safe to call in an interrupt context.
*/
unsigned long eeh_check_failure(const volatile void __iomem *token, unsigned long val)
{
unsigned long addr;
struct pci_dev *dev;
struct device_node *dn;
/* Finding the phys addr + pci device; this is pretty quick. */
addr = eeh_token_to_phys((unsigned long __force) token);
dev = pci_get_device_by_addr(addr);
if (!dev) {
no_device++;
return val;
}
dn = pci_device_to_OF_node(dev);
eeh_dn_check_failure (dn, dev);
pci_dev_put(dev);
return val;
}
