[Skiboot] [RFC PATCH 09/23] core/pcie-slot: Remove wait hack

[Oliver O'Halloran]

Now that all the users of slot->ops.set_power_state() have been converted
to expect either OPAL_SUCCESS or a wait time we cna remove the synchrnous
wait hack.

Signed-off-by: Oliver O'Halloran <oohall at gmail.com>
---
 core/pcie-slot.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/core/pcie-slot.c b/core/pcie-slot.c
index 213740a683c7..b368e5496fab 100644
--- a/core/pcie-slot.c
+++ b/core/pcie-slot.c
@@ -206,6 +206,9 @@ static int64_t pcie_slot_set_attention_state(struct pci_slot *slot,
 	return OPAL_SUCCESS;
 }
 
+#define PCIE_SLOT_POWER_IDLE 0 /* Ready to accept another power control cmd */
+#define PCIE_SLOT_POWER_WAIT 1 /* Waiting for a previous power control cmd  */
+
 static int64_t pcie_slot_set_power_state_ext(struct pci_slot *slot, uint8_t val,
 					     bool surprise_check)
 {
@@ -230,6 +233,11 @@ static int64_t pcie_slot_set_power_state_ext(struct pci_slot *slot, uint8_t val,
 		return OPAL_SUCCESS;
 	}
 
+	if (slot->power_ctl_state == PCIE_SLOT_POWER_WAIT) {
+		slot->power_ctl_state = PCIE_SLOT_POWER_IDLE;
+		return OPAL_SUCCESS;
+	}
+
 	/*
 	 * Suprise hotpluggable slots need to be handled with care since
 	 * many systems do not implement the presence detect side-band
@@ -256,6 +264,9 @@ static int64_t pcie_slot_set_power_state_ext(struct pci_slot *slot, uint8_t val,
 		 */
 	}
 
+
+	slot->power_ctl_state = PCIE_SLOT_POWER_WAIT;
+
 	slot->power_state = val;
 	ecap = pci_cap(pd, PCI_CFG_CAP_ID_EXP, false);
 	pci_cfg_read16(phb, pd->bdfn, ecap + PCICAP_EXP_SLOTCTL, &state);
@@ -275,13 +286,7 @@ static int64_t pcie_slot_set_power_state_ext(struct pci_slot *slot, uint8_t val,
 
 	pci_cfg_write16(phb, pd->bdfn, ecap + PCICAP_EXP_SLOTCTL, state);
 
-	/*
-	 * HACK: wait a bit for the link to come up. Drop this once we've
-	 * converted users of set_power_state to use the new interface
-	 */
-	time_wait_ms(10);
-
-	return OPAL_SUCCESS;
+	return 10;
 }
 
 static int64_t pcie_slot_set_power_state(struct pci_slot *slot, uint8_t val)
-- 
2.20.1