From: Pali Rohár pali@kernel.org
stable inclusion from stable-v5.10.110 commit e0e25e131d18445103b8c756e0bc05f953ce3d46 bugzilla: https://gitee.com/openeuler/kernel/issues/I574AL
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 735f5ae49e1b44742cc63ca9b5c1ffde3e94ba91 ]
The emulated bridge returns incorrect value for PCI_EXP_RTSTA register during readout in advk_pci_bridge_emul_pcie_conf_read() function: the correct bit is BIT(16), but we are setting BIT(23), because the code does *value = (isr0 & PCIE_MSG_PM_PME_MASK) << 16 where PCIE_MSG_PM_PME_MASK is BIT(7).
The code should probably have been something like *value = (!!(isr0 & PCIE_MSG_PM_PME_MASK)) << 16, but we are better of using an if() and using the proper macro for this bit.
Link: https://lore.kernel.org/r/20220110015018.26359-15-kabel@kernel.org Fixes: 8a3ebd8de328 ("PCI: aardvark: Implement emulated root PCI bridge config space") Signed-off-by: Pali Rohár pali@kernel.org Signed-off-by: Marek Behún kabel@kernel.org Signed-off-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yu Liao liaoyu15@huawei.com Reviewed-by: Wei Li liwei391@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- drivers/pci/controller/pci-aardvark.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index f30144c8c0bd..49ff8bf10c74 100644 --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -851,7 +851,9 @@ advk_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge, case PCI_EXP_RTSTA: { u32 isr0 = advk_readl(pcie, PCIE_ISR0_REG); u32 msglog = advk_readl(pcie, PCIE_MSG_LOG_REG); - *value = (isr0 & PCIE_MSG_PM_PME_MASK) << 16 | (msglog >> 16); + *value = msglog >> 16; + if (isr0 & PCIE_MSG_PM_PME_MASK) + *value |= PCI_EXP_RTSTA_PME; return PCI_BRIDGE_EMUL_HANDLED; }