FAILED: patch "[PATCH] PCI: aardvark: Use ISR1 instead of ISR0 interrupt in legacy" failed to apply to 4.9-stable tree

FAILED: patch "[PATCH] PCI: aardvark: Use ISR1 instead of ISR0 interrupt in legacy" failed to apply to 4.9-stable tree

[gregkh]

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From 3430f924a62905891c8fa9a3b97ea52007795bc3 Mon Sep 17 00:00:00 2001
From: Victor Gu <xigu@marvell.com>
Date: Fri, 6 Apr 2018 16:55:33 +0200
Subject: [PATCH] PCI: aardvark: Use ISR1 instead of ISR0 interrupt in legacy
 irq mode

The Aardvark has two interrupts sets:

 - first set is bit[23:16] of PCIe ISR 0 register(RD0074840h)

 - second set is bit[11:8] of PCIe ISR 1 register(RD0074848h)

Only one set should be used, while another set should be masked.

The second set, ISR1, is more advanced, the Legacy INT_X status bit is
asserted once Assert_INTX message is received, and de-asserted after
Deassert_INTX message is received which matches what the driver is
currently doing in the ->irq_mask() and ->irq_unmask() functions.

The ISR0 requires additional work to deassert the interrupt, which the
driver does not currently implement, therefore it needs fixing.

Update the driver to use ISR1 register set, fixing current
implementation.

Fixes: 8c39d710363c1 ("PCI: aardvark: Add Aardvark PCI host controller driver")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196339
Signed-off-by: Victor Gu <xigu@marvell.com>
[Thomas: tweak commit log.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
[lorenzo.pieralisi@arm.com: updated the commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Evan Wang <xswang@marvell.com>
Reviewed-by: Nadav Haklai <nadavh@marvell.com>
Cc: <stable@vger.kernel.org>

diff --git a/drivers/pci/host/pci-aardvark.c b/drivers/pci/host/pci-aardvark.c
index 5b8201aaf34d..7a0ddb709052 100644
--- a/drivers/pci/host/pci-aardvark.c
+++ b/drivers/pci/host/pci-aardvark.c
@@ -100,7 +100,8 @@
 #define PCIE_ISR1_MASK_REG			(CONTROL_BASE_ADDR + 0x4C)
 #define     PCIE_ISR1_POWER_STATE_CHANGE	BIT(4)
 #define     PCIE_ISR1_FLUSH			BIT(5)
-#define     PCIE_ISR1_ALL_MASK			GENMASK(5, 4)
+#define     PCIE_ISR1_INTX_ASSERT(val)		BIT(8 + (val))
+#define     PCIE_ISR1_ALL_MASK			GENMASK(11, 4)
 #define PCIE_MSI_ADDR_LOW_REG			(CONTROL_BASE_ADDR + 0x50)
 #define PCIE_MSI_ADDR_HIGH_REG			(CONTROL_BASE_ADDR + 0x54)
 #define PCIE_MSI_STATUS_REG			(CONTROL_BASE_ADDR + 0x58)
@@ -607,9 +608,9 @@ static void advk_pcie_irq_mask(struct irq_data *d)
 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
 	u32 mask;
 
-	mask = advk_readl(pcie, PCIE_ISR0_MASK_REG);
-	mask |= PCIE_ISR0_INTX_ASSERT(hwirq);
-	advk_writel(pcie, mask, PCIE_ISR0_MASK_REG);
+	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
+	mask |= PCIE_ISR1_INTX_ASSERT(hwirq);
+	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
 }
 
 static void advk_pcie_irq_unmask(struct irq_data *d)
@@ -618,9 +619,9 @@ static void advk_pcie_irq_unmask(struct irq_data *d)
 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
 	u32 mask;
 
-	mask = advk_readl(pcie, PCIE_ISR0_MASK_REG);
-	mask &= ~PCIE_ISR0_INTX_ASSERT(hwirq);
-	advk_writel(pcie, mask, PCIE_ISR0_MASK_REG);
+	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
+	mask &= ~PCIE_ISR1_INTX_ASSERT(hwirq);
+	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
 }
 
 static int advk_pcie_irq_map(struct irq_domain *h,
@@ -763,29 +764,35 @@ static void advk_pcie_handle_msi(struct advk_pcie *pcie)
 
 static void advk_pcie_handle_int(struct advk_pcie *pcie)
 {
-	u32 val, mask, status;
+	u32 isr0_val, isr0_mask, isr0_status;
+	u32 isr1_val, isr1_mask, isr1_status;
 	int i, virq;
 
-	val = advk_readl(pcie, PCIE_ISR0_REG);
-	mask = advk_readl(pcie, PCIE_ISR0_MASK_REG);
-	status = val & ((~mask) & PCIE_ISR0_ALL_MASK);
+	isr0_val = advk_readl(pcie, PCIE_ISR0_REG);
+	isr0_mask = advk_readl(pcie, PCIE_ISR0_MASK_REG);
+	isr0_status = isr0_val & ((~isr0_mask) & PCIE_ISR0_ALL_MASK);
 
-	if (!status) {
-		advk_writel(pcie, val, PCIE_ISR0_REG);
+	isr1_val = advk_readl(pcie, PCIE_ISR1_REG);
+	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 (status & PCIE_ISR0_MSI_INT_PENDING)
+	if (isr0_status & PCIE_ISR0_MSI_INT_PENDING)
 		advk_pcie_handle_msi(pcie);
 
 	/* Process legacy interrupts */
 	for (i = 0; i < PCI_NUM_INTX; i++) {
-		if (!(status & PCIE_ISR0_INTX_ASSERT(i)))
+		if (!(isr1_status & PCIE_ISR1_INTX_ASSERT(i)))
 			continue;
 
-		advk_writel(pcie, PCIE_ISR0_INTX_ASSERT(i),
-			    PCIE_ISR0_REG);
+		advk_writel(pcie, PCIE_ISR1_INTX_ASSERT(i),
+			    PCIE_ISR1_REG);
 
 		virq = irq_find_mapping(pcie->irq_domain, i);
 		generic_handle_irq(virq);