[PATCH 1/3] PCI: designware: Use interrupt masking instead of disabling

[Marc Zyngier <marc.zyngier@arm.com>]

The dwc driver is showing an interesting level of brokeness, as it
insists on using the "enable" register to mask/unmask MSIs, meaning
that an MSIs being generated while the interrupt is in that "disabled"
state will simply be lost.

Let's move to the MASK register, which offers the expected semantics.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 drivers/pci/controller/dwc/pcie-designware-host.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 29a05759a294..c3aa8b5fb51d 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -168,7 +168,7 @@ static void dw_pci_bottom_mask(struct irq_data *data)
 		bit = data->hwirq % MAX_MSI_IRQS_PER_CTRL;
 
 		pp->irq_status[ctrl] &= ~(1 << bit);
-		dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_ENABLE + res, 4,
+		dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_MASK + res, 4,
 				    pp->irq_status[ctrl]);
 	}
 
@@ -191,7 +191,7 @@ static void dw_pci_bottom_unmask(struct irq_data *data)
 		bit = data->hwirq % MAX_MSI_IRQS_PER_CTRL;
 
 		pp->irq_status[ctrl] |= 1 << bit;
-		dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_ENABLE + res, 4,
+		dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_MASK + res, 4,
 				    pp->irq_status[ctrl]);
 	}
 
-- 
2.19.1