From: Claudiu Manoil Date: Fri, 21 Mar 2014 07:33:17 +0000 (+0200) Subject: gianfar: Fix P1010 config regression (SQ polling) X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=c65d7533729a965ab8d93fa0470abc263060c54c;p=linux-beck.git gianfar: Fix P1010 config regression (SQ polling) The P1010 device tree restricts the number of supported interrupt groups to 1, although the eth controller can support 2 interrupt groups and the driver assumes the Multi-Group mode ("fsl,etsec2" model). So, in this case the assumption that the Multi-Group mode (MQ_MG_MODE) devices always support 2 interrupt groups is false. To fix this, a check for the actual number of interrupt groups enabled in the board's device tree has been added in gfar_probe for the "fsl,etsec2" devices. Without this fix, P1010 based boards claim support for 2 Tx queues to the net stack but only one is actually allocated, leading to NULL access in xmit. This issue was introduced by enabling Single-Queue polling for the P1010 devices. (71ff9e3 gianfar: Use Single-Queue polling for "fsl,etsec2") Fixes: 71ff9e3df7e1c5d3293af6b595309124e8c97412 Signed-off-by: Claudiu Manoil Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c index 6e12f9365856..9125d9abf099 100644 --- a/drivers/net/ethernet/freescale/gianfar.c +++ b/drivers/net/ethernet/freescale/gianfar.c @@ -754,9 +754,19 @@ static int gfar_of_init(struct platform_device *ofdev, struct net_device **pdev) num_tx_qs = 1; num_rx_qs = 1; } else { /* MQ_MG_MODE */ + /* get the actual number of supported groups */ + unsigned int num_grps = of_get_available_child_count(np); + + if (num_grps == 0 || num_grps > MAXGROUPS) { + dev_err(&ofdev->dev, "Invalid # of int groups(%d)\n", + num_grps); + pr_err("Cannot do alloc_etherdev, aborting\n"); + return -EINVAL; + } + if (poll_mode == GFAR_SQ_POLLING) { - num_tx_qs = 2; /* one txq per int group */ - num_rx_qs = 2; /* one rxq per int group */ + num_tx_qs = num_grps; /* one txq per int group */ + num_rx_qs = num_grps; /* one rxq per int group */ } else { /* GFAR_MQ_POLLING */ num_tx_qs = tx_queues ? *tx_queues : 1; num_rx_qs = rx_queues ? *rx_queues : 1;