[Skiboot] [PATCH 01/16] core/pci: Refactor common paths on slot hotplug

[Andrew Donnellan]

On 9/9/19 2:31 pm, Frederic Barrat wrote:
> Refactor code executed to remove or rescan devices when a slot power
> state changes, synchronously or asynchronously through a timer
> callback. It will be more useful in a future patch.
> 
> No functional changes.
> 
> Signed-off-by: Frederic Barrat <fbarrat at linux.ibm.com>

Reviewed-by: Andrew Donnellan <ajd at linux.ibm.com>

> ---
>   core/pci-opal.c | 43 ++++++++++++++++++++++++++-----------------
>   1 file changed, 26 insertions(+), 17 deletions(-)
> 
> diff --git a/core/pci-opal.c b/core/pci-opal.c
> index 213a7256..d5209600 100644
> --- a/core/pci-opal.c
> +++ b/core/pci-opal.c
> @@ -647,11 +647,30 @@ static int64_t opal_pci_get_power_state(uint64_t id, uint64_t data)
>   }
>   opal_call(OPAL_PCI_GET_POWER_STATE, opal_pci_get_power_state, 2);
>   
> +static void rescan_slot_devices(struct pci_slot *slot)
> +{
> +	struct phb *phb = slot->phb;
> +	struct pci_device *pd = slot->pd;
> +
> +	slot->ops.prepare_link_change(slot, true);
> +	pci_scan_bus(phb, pd->secondary_bus,
> +		     pd->subordinate_bus, &pd->children, pd, true);
> +	pci_add_device_nodes(phb, &pd->children, pd->dn,
> +			     &phb->lstate, 0);
> +}
> +
> +static void remove_slot_devices(struct pci_slot *slot)
> +{
> +	struct phb *phb = slot->phb;
> +	struct pci_device *pd = slot->pd;
> +
> +	pci_remove_bus(phb, &pd->children);
> +}
> +
>   static void set_power_timer(struct timer *t __unused, void *data,
>   			    uint64_t now __unused)
>   {
>   	struct pci_slot *slot = data;
> -	struct phb *phb = slot->phb;
>   	struct pci_device *pd = slot->pd;
>   	struct dt_node *dn = pd->dn;
>   	uint8_t link;
> @@ -670,7 +689,7 @@ static void set_power_timer(struct timer *t __unused, void *data,
>   		break;
>   	case PCI_SLOT_STATE_SPOWER_DONE:
>   		if (slot->power_state == OPAL_PCI_SLOT_POWER_OFF) {
> -			pci_remove_bus(phb, &pd->children);
> +			remove_slot_devices(slot);
>   			pci_slot_set_state(slot, PCI_SLOT_STATE_NORMAL);
>   			opal_queue_msg(OPAL_MSG_ASYNC_COMP, NULL, NULL,
>   				       slot->async_token, dn->phandle,
> @@ -682,12 +701,7 @@ static void set_power_timer(struct timer *t __unused, void *data,
>   		if (slot->ops.get_link_state(slot, &link) != OPAL_SUCCESS)
>   			link = 0;
>   		if (link) {
> -			slot->ops.prepare_link_change(slot, true);
> -			pci_scan_bus(phb, pd->secondary_bus,
> -				     pd->subordinate_bus,
> -				     &pd->children, pd, true);
> -			pci_add_device_nodes(phb, &pd->children, dn,
> -					     &phb->lstate, 0);
> +			rescan_slot_devices(slot);
>   			pci_slot_set_state(slot, PCI_SLOT_STATE_NORMAL);
>   			opal_queue_msg(OPAL_MSG_ASYNC_COMP, NULL, NULL,
>   				       slot->async_token, dn->phandle,
> @@ -782,15 +796,10 @@ static int64_t opal_pci_set_power_state(uint64_t async_token,
>   		init_timer(&slot->timer, set_power_timer, slot);
>   		schedule_timer(&slot->timer, msecs_to_tb(10));
>   	} else if (rc == OPAL_SUCCESS) {
> -		if (*state == OPAL_PCI_SLOT_POWER_OFF) {
> -			pci_remove_bus(phb, &pd->children);
> -		} else {
> -			slot->ops.prepare_link_change(slot, true);
> -			pci_scan_bus(phb, pd->secondary_bus,
> -				pd->subordinate_bus, &pd->children, pd, true);
> -			pci_add_device_nodes(phb, &pd->children, pd->dn,
> -				&phb->lstate, 0);
> -		}
> +		if (*state == OPAL_PCI_SLOT_POWER_OFF)
> +			remove_slot_devices(slot);
> +		else
> +			rescan_slot_devices(slot);
>   	}
>   
>   	phb_unlock(phb);
> 

-- 
Andrew Donnellan              OzLabs, ADL Canberra
ajd at linux.ibm.com             IBM Australia Limited