From a7ca6d7fa3c02c032db5440ff392d96c04684c21 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
Date: Tue, 5 Oct 2021 20:09:45 +0200
Subject: [PATCH] PCI: aardvark: Do not clear status bits of masked interrupts
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Git-commit: a7ca6d7fa3c02c032db5440ff392d96c04684c21
Patch-mainline: v5.16-rc1
References: git-fixes stable-5.14.19
The PCIE_ISR1_REG says which interrupts are currently set / active,
including those which are masked.
The driver currently reads this register and looks if some unmasked
interrupts are active, and if not, it clears status bits of _all_
interrupts, including the masked ones.
This is incorrect, since, for example, some drivers may poll these bits.
Remove this clearing, and also remove this early return statement
completely, since it does not change functionality in any way.
Link: https://lore.kernel.org/r/20211005180952.6812-7-kabel@kernel.org
Fixes: 8c39d710363c ("PCI: aardvark: Add Aardvark PCI host controller driver")
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>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/pci/controller/pci-aardvark.c | 6 ------
1 file changed, 6 deletions(-)
diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
index d5d6f92e5143..f7eebf453e83 100644
--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -1295,12 +1295,6 @@ static void advk_pcie_handle_int(struct advk_pcie *pcie)
isr1_mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
isr1_status = isr1_val & ((~isr1_mask) & PCIE_ISR1_ALL_MASK);
- if (!isr0_status && !isr1_status) {
- advk_writel(pcie, isr0_val, PCIE_ISR0_REG);
- advk_writel(pcie, isr1_val, PCIE_ISR1_REG);
- return;
- }
-
/* Process MSI interrupts */
if (isr0_status & PCIE_ISR0_MSI_INT_PENDING)
advk_pcie_handle_msi(pcie);
--
2.26.2