[PATCH v3] PCI: uniphier: Serialize INTx masking/unmasking and fix the bit operation
From: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Date: 2021-09-18 00:23:30
Also in:
linux-pci, lkml
Subsystem:
pci native host bridge and endpoint drivers, pci subsystem, pcie driver for socionext uniphier, the rest · Maintainers:
Lorenzo Pieralisi, Krzysztof Wilczyński, Manivannan Sadhasivam, Bjorn Helgaas, Kunihiko Hayashi, Linus Torvalds
The condition register PCI_RCV_INTX is used in irq_mask() and irq_unmask()
callbacks. Accesses to register can occur at the same time without a lock.
Add a lock into each callback to prevent the issue.
And INTX mask and unmask fields in PCL_RCV_INTX register should only be
set/reset for each bit. Clearing by PCL_RCV_INTX_ALL_MASK should be
removed.
INTX status fields in PCL_RCV_INTX register only indicates each INTX
interrupt status, so the handler can't clear by writing 1 to the field.
The status is expected to be cleared by the interrupt origin.
The ack function has no meaning, so should remove it.
Fixes: 7e6d5cd88a6f ("PCI: uniphier: Add UniPhier PCIe host controller support")
Suggested-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Marc Zyngier <maz@kernel.org>
---
Changes in v3:
- Squash two fix patches into one
- Add Acked-by: line
Changes in v2:
- Add Acked-by: line to the first patch
- Add a fix patch for bit operation
---
drivers/pci/controller/dwc/pcie-uniphier.c | 26 ++++++++++----------------
1 file changed, 10 insertions(+), 16 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-uniphier.c b/drivers/pci/controller/dwc/pcie-uniphier.c
index d95df02..d35501b 100644
--- a/drivers/pci/controller/dwc/pcie-uniphier.c
+++ b/drivers/pci/controller/dwc/pcie-uniphier.c@@ -194,30 +194,21 @@ static void uniphier_pcie_irq_enable(struct uniphier_pcie_priv *priv) writel(PCL_RCV_INTX_ALL_ENABLE, priv->base + PCL_RCV_INTX); } -static void uniphier_pcie_irq_ack(struct irq_data *d) -{ - struct pcie_port *pp = irq_data_get_irq_chip_data(d); - struct dw_pcie *pci = to_dw_pcie_from_pp(pp); - struct uniphier_pcie_priv *priv = to_uniphier_pcie(pci); - u32 val; - - val = readl(priv->base + PCL_RCV_INTX); - val &= ~PCL_RCV_INTX_ALL_STATUS; - val |= BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_STATUS_SHIFT); - writel(val, priv->base + PCL_RCV_INTX); -} - static void uniphier_pcie_irq_mask(struct irq_data *d) { struct pcie_port *pp = irq_data_get_irq_chip_data(d); struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct uniphier_pcie_priv *priv = to_uniphier_pcie(pci); + unsigned long flags; u32 val; + raw_spin_lock_irqsave(&pp->lock, flags); + val = readl(priv->base + PCL_RCV_INTX); - val &= ~PCL_RCV_INTX_ALL_MASK; val |= BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_MASK_SHIFT); writel(val, priv->base + PCL_RCV_INTX); + + raw_spin_unlock_irqrestore(&pp->lock, flags); } static void uniphier_pcie_irq_unmask(struct irq_data *d)
@@ -225,17 +216,20 @@ static void uniphier_pcie_irq_unmask(struct irq_data *d) struct pcie_port *pp = irq_data_get_irq_chip_data(d); struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct uniphier_pcie_priv *priv = to_uniphier_pcie(pci); + unsigned long flags; u32 val; + raw_spin_lock_irqsave(&pp->lock, flags); + val = readl(priv->base + PCL_RCV_INTX); - val &= ~PCL_RCV_INTX_ALL_MASK; val &= ~BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_MASK_SHIFT); writel(val, priv->base + PCL_RCV_INTX); + + raw_spin_unlock_irqrestore(&pp->lock, flags); } static struct irq_chip uniphier_pcie_irq_chip = { .name = "PCI", - .irq_ack = uniphier_pcie_irq_ack, .irq_mask = uniphier_pcie_irq_mask, .irq_unmask = uniphier_pcie_irq_unmask, };
--
2.7.4
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