The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3f7bb2ec20ce07c02b2002349d256c91a463fcc5 Mon Sep 17 00:00:00 2001
From: Marc Zyngier marc.zyngier@arm.com Date: Tue, 13 Nov 2018 22:57:34 +0000 Subject: [PATCH] PCI: dwc: Move interrupt acking into the proper callback
The write to the status register is really an ACK for the HW, and should be treated as such by the driver. Let's move it to the irq_ack() callback, which will prevent people from moving it around in order to paper over other bugs.
Fixes: 8c934095fa2f ("PCI: dwc: Clear MSI interrupt status after it is handled, not before") Fixes: 7c5925afbc58 ("PCI: dwc: Move MSI IRQs allocation to IRQ domains hierarchical API") Link: https://lore.kernel.org/linux-pci/20181113225734.8026-1-marc.zyngier@arm.com... Reported-by: Trent Piepho tpiepho@impinj.com Tested-by: Niklas Cassel niklas.cassel@linaro.org Tested-by: Gustavo Pimentel gustavo.pimentel@synopsys.com Tested-by: Stanimir Varbanov svarbanov@mm-sol.com Signed-off-by: Marc Zyngier marc.zyngier@arm.com [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com Cc: stable@vger.kernel.org
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index 610a5e018d27..0fa9e8fdce66 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -99,9 +99,6 @@ irqreturn_t dw_handle_msi_irq(struct pcie_port *pp) (i * MAX_MSI_IRQS_PER_CTRL) + pos); generic_handle_irq(irq); - dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_STATUS + - (i * MSI_REG_CTRL_BLOCK_SIZE), - 4, 1 << pos); pos++; } } @@ -200,14 +197,18 @@ static void dw_pci_bottom_unmask(struct irq_data *data)
static void dw_pci_bottom_ack(struct irq_data *d) { - struct msi_desc *msi = irq_data_get_msi_desc(d); - struct pcie_port *pp; + struct pcie_port *pp = irq_data_get_irq_chip_data(d); + unsigned int res, bit, ctrl; unsigned long flags;
- pp = msi_desc_to_pci_sysdata(msi); + ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL; + res = ctrl * MSI_REG_CTRL_BLOCK_SIZE; + bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;
raw_spin_lock_irqsave(&pp->lock, flags);
+ dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_STATUS + res, 4, 1 << bit); + if (pp->ops->msi_irq_ack) pp->ops->msi_irq_ack(d->hwirq, pp);