[PATCH] pci: dwc: Clear MSI interrupt status after it is handled

From	Faiz Abbas <faiz_abbas@ti.com>
Newsgroups	linux.kernel
Subject	[PATCH] pci: dwc: Clear MSI interrupt status after it is handled
Date	2017-08-10 13:30 +0200
Message-ID	<ucTP3-4V8-3@gated-at.bofh.it> (permalink)
Organization	linux.* mail to news gateway

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If the interrupt status is cleared before it is handled, it is possible
that another interrupt will trigger while servicing the previous one.
This is causing timeouts in some wireless lan cards which use pcie.
Therefore, clear MSI interrupt status after it gets serviced instead
of before calling generic_handler.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
---
 drivers/pci/dwc/pcie-designware-host.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/dwc/pcie-designware-host.c b/drivers/pci/dwc/pcie-designware-host.c
index 28ed32b..78b2584 100644
--- a/drivers/pci/dwc/pcie-designware-host.c
+++ b/drivers/pci/dwc/pcie-designware-host.c
@@ -71,9 +71,9 @@ irqreturn_t dw_handle_msi_irq(struct pcie_port *pp)
 		while ((pos = find_next_bit((unsigned long *) &val, 32,
 					    pos)) != 32) {
 			irq = irq_find_mapping(pp->irq_domain, i * 32 + pos);
+			generic_handle_irq(irq);
 			dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_STATUS + i * 12,
 					    4, 1 << pos);
-			generic_handle_irq(irq);
 			pos++;
 		}
 	}
-- 
2.7.4

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[PATCH] pci: dwc: Clear MSI interrupt status after it is handled Faiz Abbas <faiz_abbas@ti.com> - 2017-08-10 13:30 +0200

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