Hi Bhadram, On 26-10-2017 11:51, Bhadram Varka wrote: > Hi Jose, > >> -----Original Message----- >> From: [email protected] [mailto:netdev- >> [email protected]] On Behalf Of Jose Abreu >> Sent: Thursday, October 26, 2017 2:37 PM >> To: [email protected]; [email protected] >> Cc: Jose Abreu <[email protected]>; Joao Pinto >> <[email protected]>; David S. Miller <[email protected]>; >> Giuseppe Cavallaro <[email protected]>; Alexandre Torgue >> <[email protected]> >> Subject: [PATCH net] net: stmmac: First Queue must always be in DCB mode >> >> According to DWMAC databook the first queue operating mode must always >> be in DCB. >> >> As MTL_QUEUE_DCB = 1, we need to always set the first queue operating >> mode to DCB otherwise driver will think that queue is in AVB mode (because >> MTL_QUEUE_AVB = 0). >> >> Signed-off-by: Jose Abreu <[email protected]> >> Cc: Joao Pinto <[email protected]> >> Cc: David S. Miller <[email protected]> >> Cc: Giuseppe Cavallaro <[email protected]> >> Cc: Alexandre Torgue <[email protected]> >> --- >> drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c >> b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c >> index 21f59fe..603225b 100644 >> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c >> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c >> @@ -150,6 +150,13 @@ static void stmmac_mtl_setup(struct >> platform_device *pdev, >> plat->rx_queues_to_use = 1; >> plat->tx_queues_to_use = 1; >> >> + /* First Queue must always be in DCB mode. As MTL_QUEUE_DCB = >> 1 we need >> + * to always set this, otherwise Queue will be classified as AVB >> + * (because MTL_QUEUE_AVB = 0). >> + */ > Its better if we can check whether IP HW features (register - 0x120) supports > the DCB or not. If yes, then set the DCB mode. > There is possibility that DCB feature not enable for few of the Synopsys IP's.
A queue can either be in Generic/DCB or AVB mode. The sequence to enable a DCB or a Generic queue is the same so there is no need to check for DCB capability in HW. Best Regards, Jose Miguel Abreu > > Thanks, > Bhadram.
