From 413cb66bbb700adb356b7eb47cc7c843fe20a364 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 13 Nov 2018 22:57:34 +0000 Subject: [PATCH] PCI: dwc: Move interrupt acking into the proper callback commit 3f7bb2ec20ce07c02b2002349d256c91a463fcc5 upstream. 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 Tested-by: Niklas Cassel Tested-by: Gustavo Pimentel Tested-by: Stanimir Varbanov Signed-off-by: Marc Zyngier [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by: Lorenzo Pieralisi Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/pci/dwc/pcie-designware-host.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/pci/dwc/pcie-designware-host.c b/drivers/pci/dwc/pcie-designware-host.c index bc3e2d8..58b38c5 100644 --- a/drivers/pci/dwc/pcie-designware-host.c +++ b/drivers/pci/dwc/pcie-designware-host.c @@ -45,8 +45,19 @@ static int dw_pcie_wr_own_conf(struct pcie_port *pp, int where, int size, return dw_pcie_write(pci->dbi_base + where, size, val); } +static void dwc_irq_ack(struct irq_data *d) +{ + struct msi_desc *msi = irq_data_get_msi_desc(d); + struct pcie_port *pp = msi_desc_to_pci_sysdata(msi); + int pos = d->hwirq % 32; + int i = d->hwirq / 32; + + dw_pcie_wr_own_conf(pp, PCIE_MSI_INTR0_STATUS + i * 12, 4, BIT(pos)); +} + static struct irq_chip dw_msi_irq_chip = { .name = "PCI-MSI", + .irq_ack = dwc_irq_ack, .irq_enable = pci_msi_unmask_irq, .irq_disable = pci_msi_mask_irq, .irq_mask = pci_msi_mask_irq, @@ -72,8 +83,6 @@ irqreturn_t dw_handle_msi_irq(struct pcie_port *pp) 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); pos++; } } @@ -263,7 +272,7 @@ static struct msi_controller dw_pcie_msi_chip = { static int dw_pcie_msi_map(struct irq_domain *domain, unsigned int irq, irq_hw_number_t hwirq) { - irq_set_chip_and_handler(irq, &dw_msi_irq_chip, handle_simple_irq); + irq_set_chip_and_handler(irq, &dw_msi_irq_chip, handle_edge_irq); irq_set_chip_data(irq, domain->host_data); return 0; -- 2.7.4