Commit 0fc75d87 authored by Pali Rohár's avatar Pali Rohár Committed by Lorenzo Pieralisi
Browse files

PCI: aardvark: Add support for PME interrupts 

Currently enabling PCI_EXP_RTSTA_PME bit in PCI_EXP_RTCTL register does
nothing. This is because PCIe PME driver expects to receive PCIe interrupt
defined in PCI_EXP_FLAGS_IRQ register, but aardvark hardware does not
trigger PCIe INTx/MSI interrupt for PME event, rather it triggers custom
aardvark interrupt which this driver is not processing yet.

Fix this issue by handling PME interrupt in advk_pcie_handle_int() and
chaining it to PCIe interrupt 0 with generic_handle_domain_irq() (since
aardvark sets PCI_EXP_FLAGS_IRQ to zero). With this change PCIe PME driver
finally starts receiving PME interrupt.

Link: https://lore.kernel.org/r/20220110015018.26359-17-kabel@kernel.org


Signed-off-by: default avatarPali Rohár <pali@kernel.org>
Signed-off-by: default avatarMarek Behún <kabel@kernel.org>
Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
parent 7122bcb3

drivers/pci/controller/pci-aardvark.c

+12 −0
Original line number Diff line number Diff line
@@ -1478,6 +1478,18 @@ static void advk_pcie_handle_int(struct advk_pcie *pcie) 
	isr1_mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);

	isr1_status = isr1_val & ((~isr1_mask) & PCIE_ISR1_ALL_MASK);



	/* Process PME interrupt */

	if (isr0_status & PCIE_MSG_PM_PME_MASK) {

		/*

		 * Do not clear PME interrupt bit in ISR0, it is cleared by IRQ

		 * receiver by writing to the PCI_EXP_RTSTA register of emulated

		 * root bridge. Aardvark HW returns zero for PCI_EXP_FLAGS_IRQ,

		 * so use PCIe interrupt 0.

		 */

		if (generic_handle_domain_irq(pcie->irq_domain, 0) == -EINVAL)

			dev_err_ratelimited(&pcie->pdev->dev, "unhandled PME IRQ\n");

	}



	/* Process ERR interrupt */

	if (isr0_status & PCIE_ISR0_ERR_MASK) {

		advk_writel(pcie, PCIE_ISR0_ERR_MASK, PCIE_ISR0_REG);