From: Logan Gunthorpe logang@deltatee.com
[ Upstream commit ca93c45755da98302c93abdd788fc09113baf9e0 ]
This commit fixes pingpong support for existing drivers that do not implement ntb_default_port_number() and ntb_default_peer_port_number(). This is required for hardware (like the crosslink topology of switchtec) which cannot assign reasonable port numbers to each port due to its perfect symmetry.
Instead of picking the doorbell to use based on the the index of the peer, we use the peer's port number. This is a bit clearer and easier to understand.
Fixes: c7aeb0afdcc2 ("NTB: ntb_pp: Add full multi-port NTB API support") Signed-off-by: Logan Gunthorpe logang@deltatee.com Acked-by: Allen Hubbe allenbh@gmail.com Tested-by: Alexander Fomichev fomichev.ru@gmail.com Signed-off-by: Jon Mason jdmason@kudzu.us Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/ntb/test/ntb_pingpong.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-)
diff --git a/drivers/ntb/test/ntb_pingpong.c b/drivers/ntb/test/ntb_pingpong.c index 65865e460ab87..18d00eec7b025 100644 --- a/drivers/ntb/test/ntb_pingpong.c +++ b/drivers/ntb/test/ntb_pingpong.c @@ -121,15 +121,14 @@ static int pp_find_next_peer(struct pp_ctx *pp) link = ntb_link_is_up(pp->ntb, NULL, NULL);
/* Find next available peer */ - if (link & pp->nmask) { + if (link & pp->nmask) pidx = __ffs64(link & pp->nmask); - out_db = BIT_ULL(pidx + 1); - } else if (link & pp->pmask) { + else if (link & pp->pmask) pidx = __ffs64(link & pp->pmask); - out_db = BIT_ULL(pidx); - } else { + else return -ENODEV; - } + + out_db = BIT_ULL(ntb_peer_port_number(pp->ntb, pidx));
spin_lock(&pp->lock); pp->out_pidx = pidx; @@ -303,7 +302,7 @@ static void pp_init_flds(struct pp_ctx *pp) break; }
- pp->in_db = BIT_ULL(pidx); + pp->in_db = BIT_ULL(lport); pp->pmask = GENMASK_ULL(pidx, 0) >> 1; pp->nmask = GENMASK_ULL(pcnt - 1, pidx);
@@ -435,4 +434,3 @@ static void __exit pp_exit(void) debugfs_remove_recursive(pp_dbgfs_topdir); } module_exit(pp_exit); -