Fixing doorbell register length to 32bits per spec. On Skylake NTB, the
doorbell registers are 32bit write only registers. The source for the
doorbell is a 64bit register that shows the interrupt bits.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Fixes: 783dfa6cc41b ("ntb: Adding Skylake Xeon NTB support")
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
        .link_is_up             = xeon_link_is_up,
        .db_ioread              = skx_db_ioread,
        .db_iowrite             = skx_db_iowrite,
-       .db_size                = sizeof(u64),
+       .db_size                = sizeof(u32),
        .ntb_ctl                = SKX_NTBCNTL_OFFSET,
        .mw_bar                 = {2, 4},
 };