Apply port RX/TX enable operations only to active switch ports. RapidIO specification (Part 6: LP-Serial Physical Layer) recommends to keep Output Port Enable (TX) and Input Port Enable (RX) control bits in disabled state (0b0) after device reset. It also allows to have implementation specific reset state for these bits.
This patch ensures that TX/RX enable action is applied only to active switch's ports while preserving an initial state of inactive ones. Signed-off-by: Alexandre Bounine <alexandre.boun...@idt.com> Cc: Matt Porter <mpor...@kernel.crashing.org> --- RESEND: Initial submission of this patch was dropped due to feedback comment which raised concern about some RapidIO switch implementations that may be affected by the change. After specification and device details review this patch declared to be safe because it preserves any combination of initial states of RX/TX enable for inactive port. drivers/rapidio/rio-scan.c | 9 +++++---- 1 files changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/rapidio/rio-scan.c b/drivers/rapidio/rio-scan.c index 2bebd79..02e686b 100644 --- a/drivers/rapidio/rio-scan.c +++ b/drivers/rapidio/rio-scan.c @@ -839,12 +839,10 @@ static int __devinit rio_enum_peer(struct rio_net *net, struct rio_mport *port, for (port_num = 0; port_num < RIO_GET_TOTAL_PORTS(rdev->swpinfo); port_num++) { - /*Enable Input Output Port (transmitter reviever)*/ - rio_enable_rx_tx_port(port, 0, + if (sw_inport == port_num) { + rio_enable_rx_tx_port(port, 0, RIO_ANY_DESTID(port->sys_size), hopcount, port_num); - - if (sw_inport == port_num) { rdev->rswitch->port_ok |= (1 << port_num); continue; } @@ -857,6 +855,9 @@ static int __devinit rio_enum_peer(struct rio_net *net, struct rio_mport *port, pr_debug( "RIO: scanning device on port %d\n", port_num); + rio_enable_rx_tx_port(port, 0, + RIO_ANY_DESTID(port->sys_size), + hopcount, port_num); rdev->rswitch->port_ok |= (1 << port_num); rio_route_add_entry(rdev, RIO_GLOBAL_TABLE, RIO_ANY_DESTID(port->sys_size), -- 1.7.8.4 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev