From 838ff44a398ff47fe9b924961d91aee325821220 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Pali=20Roh=C3=A1r?= Date: Thu, 25 Nov 2021 13:46:04 +0100 Subject: [PATCH] PCI: mvebu: Fix support for PCI_EXP_RTSTA on emulated bridge MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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: 1f08673eef12 ("PCI: mvebu: Convert to PCI emulated bridge config space") Signed-off-by: Pali Rohár Signed-off-by: Lorenzo Pieralisi --- drivers/pci/controller/pci-mvebu.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c index a863b26..bc350bd 100644 --- a/drivers/pci/controller/pci-mvebu.c +++ b/drivers/pci/controller/pci-mvebu.c @@ -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; } } -- 2.7.4