[PATCH 1/4] PCI: Xilinx NWL: Fix, do not check for legacy status in while loop

From: Bharat Kumar Gogada
Date: Sat Jan 21 2017 - 06:46:54 EST


- The legacy status register value for particular INTx becomes low
only after DEASSERT_INTx is received.
- Few End Points take time for sending DEASSERT_INTx, checking
legacy status register in while loop causes invoking of EP
handler continuosly until DEASSERT_INTx is received.

Signed-off-by: Bharat Kumar Gogada <bharatku@xxxxxxxxxx>
---
drivers/pci/host/pcie-xilinx-nwl.c | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/host/pcie-xilinx-nwl.c b/drivers/pci/host/pcie-xilinx-nwl.c
index 43eaa4a..c8b5a33 100644
--- a/drivers/pci/host/pcie-xilinx-nwl.c
+++ b/drivers/pci/host/pcie-xilinx-nwl.c
@@ -342,9 +342,10 @@ static void nwl_pcie_leg_handler(struct irq_desc *desc)

chained_irq_enter(chip, desc);
pcie = irq_desc_get_handler_data(desc);
+ status = nwl_bridge_readl(pcie, MSGF_LEG_STATUS) &
+ MSGF_LEG_SR_MASKALL;

- while ((status = nwl_bridge_readl(pcie, MSGF_LEG_STATUS) &
- MSGF_LEG_SR_MASKALL) != 0) {
+ if (status != 0) {
for_each_set_bit(bit, &status, INTX_NUM) {
virq = irq_find_mapping(pcie->legacy_irq_domain,
bit + 1);
--
1.7.1