Commit 838ff44a authored by Pali Rohár's avatar Pali Rohár Committed by Lorenzo Pieralisi
Browse files

PCI: mvebu: Fix support for PCI_EXP_RTSTA on emulated bridge 

PME Status bit in Root Status Register (PCIE_RC_RTSTA_OFF) is read-only and
can be cleared only by writing 0b to the Interrupt Cause RW0C register
(PCIE_INT_CAUSE_OFF).

Link: https://lore.kernel.org/r/20211125124605.25915-15-pali@kernel.org


Fixes: 1f08673e ("PCI: mvebu: Convert to PCI emulated bridge config space")
Signed-off-by: default avatarPali Rohár <pali@kernel.org>
Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
parent ecae073e

drivers/pci/controller/pci-mvebu.c

+10 −1
Original line number Diff line number Diff line
@@ -51,6 +51,8 @@ 
	 PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where) | \

	 PCIE_CONF_ADDR_EN)

#define PCIE_CONF_DATA_OFF	0x18fc

#define PCIE_INT_CAUSE_OFF	0x1900

#define  PCIE_INT_PM_PME		BIT(28)

#define PCIE_MASK_OFF		0x1910

#define  PCIE_MASK_ENABLE_INTS          0x0f000000

#define PCIE_CTRL_OFF		0x1a00
@@ -661,7 +663,14 @@ mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge, 
		break;



	case PCI_EXP_RTSTA:

		mvebu_writel(port, new, PCIE_RC_RTSTA);

		/*

		 * PME Status bit in Root Status Register (PCIE_RC_RTSTA)

		 * is read-only and can be cleared only by writing 0b to the

		 * Interrupt Cause RW0C register (PCIE_INT_CAUSE_OFF). So

		 * clear PME via Interrupt Cause.

		 */

		if (new & PCI_EXP_RTSTA_PME)

			mvebu_writel(port, ~PCIE_INT_PM_PME, PCIE_INT_CAUSE_OFF);

		break;

	}

}