iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

PCI: mvebu: Fix support for PCI_EXP_RTSTA on emulated bridge

Browse Source 
[ Upstream commit 838ff44a398ff47fe9b924961d91aee325821220 ]

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 <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Pali Rohár 2021-11-25 13:46:04 +01:00 committed by Greg Kroah-Hartman
parent 1d4200e284
commit a247456733
1 changed files with 10 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
drivers/pci/controller/pci-mvebu.c
View File

@ -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
@ -604,7 +606,14 @@ 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;
}
}