This is a note to let you know that I've just added the patch titled
PCI: uniphier: Serialize INTx masking/unmasking and fix the bit operation
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pci-uniphier-serialize-intx-masking-unmasking-and-fi.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit c423029c4b8367c1e6c5666698266f595585a8b8
Author: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
Date: Sat Sep 18 09:22:59 2021 +0900
PCI: uniphier: Serialize INTx masking/unmasking and fix the bit operation
[ Upstream commit 4caab28a6215da5f3c1b505ff08810bc6acfe365 ]
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.
Suggested-by: Pali Rohár <pali@xxxxxxxxxx>
Link: https://lore.kernel.org/r/1631924579-24567-1-git-send-email-hayashi.kunihiko@xxxxxxxxxxxxx
Fixes: 7e6d5cd88a6f ("PCI: uniphier: Add UniPhier PCIe host controller support")
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Acked-by: Pali Rohár <pali@xxxxxxxxxx>
Acked-by: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/pci/controller/dwc/pcie-uniphier.c b/drivers/pci/controller/dwc/pcie-uniphier.c
index 48176265c867e..527ec8aeb602f 100644
--- a/drivers/pci/controller/dwc/pcie-uniphier.c
+++ b/drivers/pci/controller/dwc/pcie-uniphier.c
@@ -171,30 +171,21 @@ 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)
@@ -202,17 +193,20 @@ 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,
};
