Same as in commit a3b69dd0ad62 ("Revert "PCI: aardvark: Rewrite IRQ code to
chained IRQ handler"") for pci-aardvark driver, use devm_request_irq()
instead of chained IRQ handler in pci-mvebu.c driver.
This change fixes affinity support and allows to pin interrupts from
different PCIe controllers to different CPU cores.
Fixes: ec075262648f ("PCI: mvebu: Implement support for legacy INTx interrupts")
Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
---
Hello Bjorn! This is basically same issue as for pci-aardvark.c:
https://lore.kernel.org/linux-pci/20220515125815.30157-1-pali@xxxxxxxxxx/#t
I tested this patch with pci=nomsi in cmdline (to force kernel to use
legacy intx instead of MSI) on A385 and checked that I can set affinity
via /proc/irq/XX/smp_affinity file for every mvebu pcie controller to
different CPU and legacy interrupts from different cards/controllers
were handled by different CPUs.
I think that this is important on Armada XP platforms which have many
independent PCIe controllers (IIRC up to 10) and many cores (up to 4).
---
drivers/pci/controller/pci-mvebu.c | 30 +++++++++++++++++-------------
1 file changed, 17 insertions(+), 13 deletions(-)
diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
index 8f76d4bda356..de67ea39fea5 100644
--- a/drivers/pci/controller/pci-mvebu.c
+++ b/drivers/pci/controller/pci-mvebu.c
@@ -1017,16 +1017,13 @@ static int mvebu_pcie_init_irq_domain(struct mvebu_pcie_port *port)
return 0;
}
-static void mvebu_pcie_irq_handler(struct irq_desc *desc)
+static irqreturn_t mvebu_pcie_irq_handler(int irq, void *arg)
{
- struct mvebu_pcie_port *port = irq_desc_get_handler_data(desc);
- struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct mvebu_pcie_port *port = arg;
struct device *dev = &port->pcie->pdev->dev;
u32 cause, unmask, status;
int i;
- chained_irq_enter(chip, desc);
-
cause = mvebu_readl(port, PCIE_INT_CAUSE_OFF);
unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
status = cause & unmask;
@@ -1040,7 +1037,7 @@ static void mvebu_pcie_irq_handler(struct irq_desc *desc)
dev_err_ratelimited(dev, "unexpected INT%c IRQ\n", (char)i+'A');
}
- chained_irq_exit(chip, desc);
+ return status ? IRQ_HANDLED : IRQ_NONE;
}
static int mvebu_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
@@ -1490,9 +1487,20 @@ static int mvebu_pcie_probe(struct platform_device *pdev)
mvebu_pcie_powerdown(port);
continue;
}
- irq_set_chained_handler_and_data(irq,
- mvebu_pcie_irq_handler,
- port);
+
+ ret = devm_request_irq(dev, irq, mvebu_pcie_irq_handler,
+ IRQF_SHARED | IRQF_NO_THREAD,
+ port->name, port);
+ if (ret) {
+ dev_err(dev, "%s: cannot register interrupt handler: %d\n",
+ port->name, ret);
+ irq_domain_remove(port->intx_irq_domain);
+ pci_bridge_emul_cleanup(&port->bridge);
+ devm_iounmap(dev, port->base);
+ port->base = NULL;
+ mvebu_pcie_powerdown(port);
+ continue;
+ }
}
/*
@@ -1599,7 +1607,6 @@ static int mvebu_pcie_remove(struct platform_device *pdev)
for (i = 0; i < pcie->nports; i++) {
struct mvebu_pcie_port *port = &pcie->ports[i];
- int irq = port->intx_irq;
if (!port->base)
continue;
@@ -1615,9 +1622,6 @@ static int mvebu_pcie_remove(struct platform_device *pdev)
/* Clear all interrupt causes. */
mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF);
- if (irq > 0)
- irq_set_chained_handler_and_data(irq, NULL, NULL);
-
/* Remove IRQ domains. */
if (port->intx_irq_domain)
irq_domain_remove(port->intx_irq_domain);
--
2.20.1
