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From: Sinan Kaya <okaya@codeaurora.org>
Date: Sun, 25 Mar 2018 10:39:16 -0400
Subject: qlcnic: Eliminate duplicate barriers on weakly-ordered archs
Patch-mainline: v4.17-rc1
Git-commit: f9442ac498a86b1b0ec383a332be2635fbb1ed98
References: bsc#1104396 FATE#325894

Code includes wmb() followed by writel(). writel() already has a
barrier on some architectures like arm64.

This ends up CPU observing two barriers back to back before executing
the register write.

Since code already has an explicit barrier call, changing writel() to
writel_relaxed().

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Acked-by: Manish Chopra <manish.chopra@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: David Chang <dchang@suse.com>
---
 drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c
@@ -478,7 +478,7 @@ irqreturn_t qlcnic_83xx_clear_legacy_int
 	wmb();
 
 	/* clear the interrupt trigger control register */
-	writel(0, adapter->isr_int_vec);
+	writel_relaxed(0, adapter->isr_int_vec);
 	intr_val = readl(adapter->isr_int_vec);
 	do {
 		intr_val = readl(adapter->tgt_status_reg);