int pciehp_power_on_slot(struct slot * slot)
{
struct controller *ctrl = slot->ctrl;
u16 slot_cmd;
u16 cmd_mask;
u16 slot_status;
u16 lnk_status;
int retval = 0;
/* Clear sticky power-fault bit from previous power failures */
retval = pciehp_readw(ctrl, PCI_EXP_SLTSTA, &slot_status);
if (retval) {
ctrl_err(ctrl, "%s: Cannot read SLOTSTATUS register\n",
__func__);
return retval;
}
slot_status &= PCI_EXP_SLTSTA_PFD;
if (slot_status) {
retval = pciehp_writew(ctrl, PCI_EXP_SLTSTA, slot_status);
if (retval) {
ctrl_err(ctrl,
"%s: Cannot write to SLOTSTATUS register\n",
__func__);
return retval;
}
}
ctrl->power_fault_detected = 0;
slot_cmd = POWER_ON;
cmd_mask = PCI_EXP_SLTCTL_PCC;
retval = pcie_write_cmd(ctrl, slot_cmd, cmd_mask);
if (retval) {
ctrl_err(ctrl, "Write %x command failed!\n", slot_cmd);
return retval;
}
ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
retval = pciehp_readw(ctrl, PCI_EXP_LNKSTA, &lnk_status);
if (retval) {
ctrl_err(ctrl, "%s: Cannot read LNKSTA register\n",
__func__);
return retval;
}
pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status);
return retval;
}
static irqreturn_t pcie_bw_notification_irq(int irq, void *context)
{
struct pcie_device *srv = context;
struct pci_dev *port = srv->port;
u16 link_status, events;
int ret;
ret = pcie_capability_read_word(port, PCI_EXP_LNKSTA, &link_status);
events = link_status & PCI_EXP_LNKSTA_LBMS;
if (ret != PCIBIOS_SUCCESSFUL || !events)
return IRQ_NONE;
pcie_capability_write_word(port, PCI_EXP_LNKSTA, events);
pcie_update_link_speed(port->subordinate, link_status);
return IRQ_WAKE_THREAD;
}
int pciehp_check_link_status(struct controller *ctrl)
{
u16 lnk_status;
int retval = 0;
bool found = false;
/*
* Data Link Layer Link Active Reporting must be capable for
* hot-plug capable downstream port. But old controller might
* not implement it. In this case, we wait for 1000 ms.
*/
if (ctrl->link_active_reporting)
pcie_wait_link_active(ctrl);
else
msleep(1000);
/* wait 100ms before read pci conf, and try in 1s */
msleep(100);
found = pci_bus_check_dev(ctrl->pcie->port->subordinate,
PCI_DEVFN(0, 0));
retval = pciehp_readw(ctrl, PCI_EXP_LNKSTA, &lnk_status);
if (retval) {
ctrl_err(ctrl, "Cannot read LNKSTATUS register\n");
return retval;
}
ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
if ((lnk_status & PCI_EXP_LNKSTA_LT) ||
!(lnk_status & PCI_EXP_LNKSTA_NLW)) {
ctrl_err(ctrl, "Link Training Error occurs \n");
retval = -1;
return retval;
}
pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status);
if (!found && !retval)
retval = -1;
return retval;
}