[hermon] Add missing write barrier after initiating reset

Ensure that the reset register write does not get reordered behind the
first PCI configuration space read that checks to see if the reset has
completed.

Debugged-by: Jaroslav Svoboda <multi.flexi@seznam.cz>
Tested-by: Jaroslav Svoboda <multi.flexi@seznam.cz>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/drivers/infiniband/hermon.c b/src/drivers/infiniband/hermon.c
index 70e9e4d54b23d7cd80167670f2d359a395ab2428..1f2bf66f52a2b5bd4489c3b281d54573f5bb0825 100644 (file)
--- a/src/drivers/infiniband/hermon.c
+++ b/src/drivers/infiniband/hermon.c
@@ -2843,6 +2843,7 @@ static int hermon_reset ( struct hermon *hermon ) {
        pci_backup ( pci, &backup, PCI_CONFIG_BACKUP_ALL, backup_exclude );
        writel ( HERMON_RESET_MAGIC,
                 ( hermon->config + HERMON_RESET_OFFSET ) );
+       wmb();
 
        /* Wait until device starts responding to configuration cycles */
        for ( i = 0 ; i < HERMON_RESET_MAX_WAIT_MS ; i++ ) {