mvneta.c, MVNETA_TXQ_UPDATE_REG, shut down issue

Hi Rami and Thomas,

I try to run vanilla kernel 4.2.0 on custom Armada-370 board, based on
DB-88F6710-BP.

The problem is that the board shuts down after writing to
MVNETA_TXQ_UPDATE_REG in this code:

static void mvneta_txq_pend_desc_add(struct mvneta_port *pp,
                                     struct mvneta_tx_queue *txq,
                                     int pend_desc)
{
        u32 val;

        /* Only 255 descriptors can be added at once ; Assume caller
         * process TX desriptors in quanta less than 256
         */
        val = pend_desc;
        mvreg_write(pp, MVNETA_TXQ_UPDATE_REG(txq->id), val);
}

BTW, pend_desc == 1

What can you suggest?

Thanks
Constantine