From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ale.deltatee.com (ale.deltatee.com. [207.54.116.67]) by gmr-mx.google.com with ESMTPS id h9-v6si99325pgp.5.2018.07.20.11.00.45 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 20 Jul 2018 11:00:46 -0700 (PDT) From: Logan Gunthorpe Date: Fri, 20 Jul 2018 12:00:30 -0600 Message-Id: <20180720180034.3964-5-logang@deltatee.com> In-Reply-To: <20180720180034.3964-1-logang@deltatee.com> References: <20180720180034.3964-1-logang@deltatee.com> Subject: [PATCH v2 4/8] NTB: ntb_pingpong: Choose doorbells based on port number To: linux-kernel@vger.kernel.org, linux-ntb@googlegroups.com, Jon Mason Cc: Allen Hubbe , Serge Semin , Shyam Sundar S K , Shuah Khan , Doug Meyer , Logan Gunthorpe List-ID: 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 --- 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 65865e460ab8..18d00eec7b02 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); - -- 2.11.0