From 4e8c11b7fd29f70eb7af43bae908297689f2c3da Mon Sep 17 00:00:00 2001 From: Serge Semin Date: Wed, 14 Dec 2016 02:49:15 +0300 Subject: NTB: Alter link-state API to support multi-port devices Multi-port devices permit the NTB connections between multiple domains, so a local device can have NTB link being up with one peer and being down with another. NTB link-state API is appropriately altered to return a bitfield of the link-states between the local device and possible peers. Signed-off-by: Serge Semin Acked-by: Allen Hubbe Signed-off-by: Jon Mason --- drivers/ntb/hw/amd/ntb_hw_amd.c | 2 +- drivers/ntb/hw/intel/ntb_hw_intel.c | 2 +- include/linux/ntb.h | 31 ++++++++++++++++--------------- 3 files changed, 18 insertions(+), 17 deletions(-) diff --git a/drivers/ntb/hw/amd/ntb_hw_amd.c b/drivers/ntb/hw/amd/ntb_hw_amd.c index 019a158e1128..e71ab4c1fe0e 100644 --- a/drivers/ntb/hw/amd/ntb_hw_amd.c +++ b/drivers/ntb/hw/amd/ntb_hw_amd.c @@ -212,7 +212,7 @@ static int amd_link_is_up(struct amd_ntb_dev *ndev) return 0; } -static int amd_ntb_link_is_up(struct ntb_dev *ntb, +static u64 amd_ntb_link_is_up(struct ntb_dev *ntb, enum ntb_speed *speed, enum ntb_width *width) { diff --git a/drivers/ntb/hw/intel/ntb_hw_intel.c b/drivers/ntb/hw/intel/ntb_hw_intel.c index 7b3b6fd63d7d..6b25bf816f28 100644 --- a/drivers/ntb/hw/intel/ntb_hw_intel.c +++ b/drivers/ntb/hw/intel/ntb_hw_intel.c @@ -1171,7 +1171,7 @@ static int intel_ntb_mw_set_trans(struct ntb_dev *ntb, int idx, return 0; } -static int intel_ntb_link_is_up(struct ntb_dev *ntb, +static u64 intel_ntb_link_is_up(struct ntb_dev *ntb, enum ntb_speed *speed, enum ntb_width *width) { diff --git a/include/linux/ntb.h b/include/linux/ntb.h index d23483bae6f3..b2b2924f5f43 100644 --- a/include/linux/ntb.h +++ b/include/linux/ntb.h @@ -235,7 +235,7 @@ struct ntb_dev_ops { int (*peer_port_number)(struct ntb_dev *ntb, int pidx); int (*peer_port_idx)(struct ntb_dev *ntb, int port); - int (*link_is_up)(struct ntb_dev *ntb, + u64 (*link_is_up)(struct ntb_dev *ntb, enum ntb_speed *speed, enum ntb_width *width); int (*link_enable)(struct ntb_dev *ntb, enum ntb_speed max_speed, enum ntb_width max_width); @@ -607,25 +607,26 @@ static inline int ntb_peer_port_idx(struct ntb_dev *ntb, int port) * state once after every link event. It is safe to query the link state in * the context of the link event callback. * - * Return: One if the link is up, zero if the link is down, otherwise a - * negative value indicating the error number. + * Return: bitfield of indexed ports link state: bit is set/cleared if the + * link is up/down respectively. */ -static inline int ntb_link_is_up(struct ntb_dev *ntb, +static inline u64 ntb_link_is_up(struct ntb_dev *ntb, enum ntb_speed *speed, enum ntb_width *width) { return ntb->ops->link_is_up(ntb, speed, width); } /** - * ntb_link_enable() - enable the link on the secondary side of the ntb + * ntb_link_enable() - enable the local port ntb connection * @ntb: NTB device context. * @max_speed: The maximum link speed expressed as PCIe generation number. * @max_width: The maximum link width expressed as the number of PCIe lanes. * - * Enable the link on the secondary side of the ntb. This can only be done - * from the primary side of the ntb in primary or b2b topology. The ntb device - * should train the link to its maximum speed and width, or the requested speed - * and width, whichever is smaller, if supported. + * Enable the NTB/PCIe link on the local or remote (for bridge-to-bridge + * topology) side of the bridge. If it's supported the ntb device should train + * the link to its maximum speed and width, or the requested speed and width, + * whichever is smaller. Some hardware doesn't support PCIe link training, so + * the last two arguments will be ignored then. * * Return: Zero on success, otherwise an error number. */ @@ -637,14 +638,14 @@ static inline int ntb_link_enable(struct ntb_dev *ntb, } /** - * ntb_link_disable() - disable the link on the secondary side of the ntb + * ntb_link_disable() - disable the local port ntb connection * @ntb: NTB device context. * - * Disable the link on the secondary side of the ntb. This can only be - * done from the primary side of the ntb in primary or b2b topology. The ntb - * device should disable the link. Returning from this call must indicate that - * a barrier has passed, though with no more writes may pass in either - * direction across the link, except if this call returns an error number. + * Disable the link on the local or remote (for b2b topology) of the ntb. + * The ntb device should disable the link. Returning from this call must + * indicate that a barrier has passed, though with no more writes may pass in + * either direction across the link, except if this call returns an error + * number. * * Return: Zero on success, otherwise an error number. */ -- cgit v1.2.3-58-ga151