[Skiboot] [PATCH v3 2/8] core/pci: Introduce a new pci_slot_op named completed_sm_run()

[Vaibhav Jain]

At times we need to perform some cleanup activities when the Opal PCI
state machine that perform creset/freset/hreset (driven by
pci_slot_ops->run_sm which) of a slot completes. One example can be to
mark CAPP attached to a PHB, as deactivated when creset/freset of a
CAPI card slot is completed.

However the calls to pci_slot_ops->run_sm() is scattered through out
the code and patching each call site to check for the return value and
perform custom cleanup tacks is difficult.

Hence this patch introduces a new pci_slot_ops named
completed_sm_run() which should be called when pci_slot_ops->run_sm()
determines that the reset state machine is complete. This provides a
more centralized way to handle slot related cleanup activities.

Reviewed-by: Andrew Donnellan <andrew.donnellan at au1.ibm.com>
Reviewed-by: Christophe Lombard <clombard at linux.vnet.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav at linux.ibm.com>
---
Change-log

v3:	None. Respinning the patchset

v2: 	Update the callback signature to return a int64_t back to
	caller. [Andrew]
---
 core/pci-slot.c    | 6 +++++-
 include/pci-slot.h | 1 +
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/core/pci-slot.c b/core/pci-slot.c
index 71d2769e..497d0a47 100644
--- a/core/pci-slot.c
+++ b/core/pci-slot.c
@@ -104,9 +104,13 @@ static int64_t pci_slot_run_sm(struct pci_slot *slot)
 		prlog(PR_ERR, PCI_SLOT_PREFIX
 		      "Invalid state %08x\n", slot->id, slot->state);
 		pci_slot_set_state(slot, PCI_SLOT_STATE_NORMAL);
-		return OPAL_HARDWARE;
+		ret = OPAL_HARDWARE;
 	}
 
+	/* Notify about the pci slot state machine completion */
+	if (ret <= 0 && slot->ops.completed_sm_run)
+		slot->ops.completed_sm_run(slot, ret);
+
 	return ret;
 }
 
diff --git a/include/pci-slot.h b/include/pci-slot.h
index cd757535..708374b6 100644
--- a/include/pci-slot.h
+++ b/include/pci-slot.h
@@ -110,6 +110,7 @@ struct pci_slot_ops {
 	int64_t (*freset)(struct pci_slot *slot);
 	int64_t (*hreset)(struct pci_slot *slot);
 	int64_t (*run_sm)(struct pci_slot *slot);
+	int64_t (*completed_sm_run)(struct pci_slot *slot, uint64_t err);
 
 	/* Auxillary functions */
 	void (*add_properties)(struct pci_slot *slot, struct dt_node *np);
-- 
2.20.1