From 8e13f70be05ee49985dfc3c766868bc85ed43b8a Mon Sep 17 00:00:00 2001 From: Samuel Mendoza-Jonas Date: Fri, 16 Nov 2018 15:51:55 +1100 Subject: net/ncsi: Probe single packages to avoid conflict Currently the NCSI driver sends a select-package command to all possible packages simultaneously to discover what packages are available. However at this stage in the probe process the driver does not know if hardware arbitration is available: if it isn't then this process could cause collisions on the RMII bus when packages try to respond. Update the probe loop to probe each package one by one, and once complete check if HWA is universally supported. Signed-off-by: Samuel Mendoza-Jonas Signed-off-by: David S. Miller --- net/ncsi/ncsi-manage.c | 85 ++++++++++++++++++-------------------------------- 1 file changed, 30 insertions(+), 55 deletions(-) (limited to 'net/ncsi/ncsi-manage.c') diff --git a/net/ncsi/ncsi-manage.c b/net/ncsi/ncsi-manage.c index d4e6e0f99097..02421d1a22c9 100644 --- a/net/ncsi/ncsi-manage.c +++ b/net/ncsi/ncsi-manage.c @@ -1079,67 +1079,28 @@ static void ncsi_probe_channel(struct ncsi_dev_priv *ndp) nd->state = ncsi_dev_state_probe_package; break; case ncsi_dev_state_probe_package: - ndp->pending_req_num = 16; + ndp->pending_req_num = 1; - /* Select all possible packages */ nca.type = NCSI_PKT_CMD_SP; nca.bytes[0] = 1; + nca.package = ndp->package_probe_id; nca.channel = NCSI_RESERVED_CHANNEL; - for (index = 0; index < 8; index++) { - nca.package = index; - ret = ncsi_xmit_cmd(&nca); - if (ret) - goto error; - } - - /* Disable all possible packages */ - nca.type = NCSI_PKT_CMD_DP; - for (index = 0; index < 8; index++) { - nca.package = index; - ret = ncsi_xmit_cmd(&nca); - if (ret) - goto error; - } - + ret = ncsi_xmit_cmd(&nca); + if (ret) + goto error; nd->state = ncsi_dev_state_probe_channel; break; case ncsi_dev_state_probe_channel: - if (!ndp->active_package) - ndp->active_package = list_first_or_null_rcu( - &ndp->packages, struct ncsi_package, node); - else if (list_is_last(&ndp->active_package->node, - &ndp->packages)) - ndp->active_package = NULL; - else - ndp->active_package = list_next_entry( - ndp->active_package, node); - - /* All available packages and channels are enumerated. The - * enumeration happens for once when the NCSI interface is - * started. So we need continue to start the interface after - * the enumeration. - * - * We have to choose an active channel before configuring it. - * Note that we possibly don't have active channel in extreme - * situation. - */ + ndp->active_package = ncsi_find_package(ndp, + ndp->package_probe_id); if (!ndp->active_package) { - ndp->flags |= NCSI_DEV_PROBED; - ncsi_choose_active_channel(ndp); - return; + /* No response */ + nd->state = ncsi_dev_state_probe_dp; + schedule_work(&ndp->work); + break; } - - /* Select the active package */ - ndp->pending_req_num = 1; - nca.type = NCSI_PKT_CMD_SP; - nca.bytes[0] = 1; - nca.package = ndp->active_package->id; - nca.channel = NCSI_RESERVED_CHANNEL; - ret = ncsi_xmit_cmd(&nca); - if (ret) - goto error; - nd->state = ncsi_dev_state_probe_cis; + schedule_work(&ndp->work); break; case ncsi_dev_state_probe_cis: ndp->pending_req_num = NCSI_RESERVED_CHANNEL; @@ -1188,22 +1149,35 @@ static void ncsi_probe_channel(struct ncsi_dev_priv *ndp) case ncsi_dev_state_probe_dp: ndp->pending_req_num = 1; - /* Deselect the active package */ + /* Deselect the current package */ nca.type = NCSI_PKT_CMD_DP; - nca.package = ndp->active_package->id; + nca.package = ndp->package_probe_id; nca.channel = NCSI_RESERVED_CHANNEL; ret = ncsi_xmit_cmd(&nca); if (ret) goto error; - /* Scan channels in next package */ - nd->state = ncsi_dev_state_probe_channel; + /* Probe next package */ + ndp->package_probe_id++; + if (ndp->package_probe_id >= 8) { + /* Probe finished */ + ndp->flags |= NCSI_DEV_PROBED; + break; + } + nd->state = ncsi_dev_state_probe_package; + ndp->active_package = NULL; break; default: netdev_warn(nd->dev, "Wrong NCSI state 0x%0x in enumeration\n", nd->state); } + if (ndp->flags & NCSI_DEV_PROBED) { + /* Check if all packages have HWA support */ + ncsi_check_hwa(ndp); + ncsi_choose_active_channel(ndp); + } + return; error: netdev_err(ndp->ndev.dev, @@ -1564,6 +1538,7 @@ int ncsi_start_dev(struct ncsi_dev *nd) return -ENOTTY; if (!(ndp->flags & NCSI_DEV_PROBED)) { + ndp->package_probe_id = 0; nd->state = ncsi_dev_state_probe; schedule_work(&ndp->work); return 0; -- cgit v1.2.3