diff options
-rw-r--r-- | drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c index 0a87a32..b4ace19 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c @@ -1128,18 +1128,26 @@ static const struct file_operations devlog_fops = { static int mbox_show(struct seq_file *seq, void *v) { static const char * const owner[] = { "none", "FW", "driver", - "unknown" }; + "unknown", "<unread>" }; int i; unsigned int mbox = (uintptr_t)seq->private & 7; struct adapter *adap = seq->private - mbox; void __iomem *addr = adap->regs + PF_REG(mbox, CIM_PF_MAILBOX_DATA_A); - unsigned int ctrl_reg = (is_t4(adap->params.chip) - ? CIM_PF_MAILBOX_CTRL_A - : CIM_PF_MAILBOX_CTRL_SHADOW_COPY_A); - void __iomem *ctrl = adap->regs + PF_REG(mbox, ctrl_reg); - i = MBOWNER_G(readl(ctrl)); + /* For T4 we don't have a shadow copy of the Mailbox Control register. + * And since reading that real register causes a side effect of + * granting ownership, we're best of simply not reading it at all. + */ + if (is_t4(adap->params.chip)) { + i = 4; /* index of "<unread>" */ + } else { + unsigned int ctrl_reg = CIM_PF_MAILBOX_CTRL_SHADOW_COPY_A; + void __iomem *ctrl = adap->regs + PF_REG(mbox, ctrl_reg); + + i = MBOWNER_G(readl(ctrl)); + } + seq_printf(seq, "mailbox owned by %s\n\n", owner[i]); for (i = 0; i < MBOX_LEN; i += 8) |