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authorSander Vanheule <sander@svanheule.net>2022-01-09 15:54:33 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2022-02-01 17:27:15 +0100
commite905e1b65ce997bdf5bed4b5eb8c14ec26cbf0ed (patch)
tree4096698128efd5fb15d7fb328faaffd40e2564cb /drivers/irqchip
parentf67594cbf3c8e6226b7e15ba978f5213bba8a75a (diff)
irqchip/realtek-rtl: Fix off-by-one in routing
commit 91351b5dd0fd494eb2d85e1bb6aca77b067447e0 upstream. There is an offset between routing values (1..6) and the connected MIPS CPU interrupts (2..7), but no distinction was made between these two values. This issue was previously hidden during testing, because an interrupt mapping was used where for each required interrupt another (unused) routing was configured, with an offset of +1. Offset the CPU IRQ numbers by -1 to retrieve the correct routing value. Fixes: 9f3a0f34b84a ("irqchip: Add support for Realtek RTL838x/RTL839x interrupt controller") Signed-off-by: Sander Vanheule <sander@svanheule.net> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/177b920aa8d8610615692d0e657e509f363c85ca.1641739718.git.sander@svanheule.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/irqchip')
-rw-r--r--drivers/irqchip/irq-realtek-rtl.c8
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/irqchip/irq-realtek-rtl.c b/drivers/irqchip/irq-realtek-rtl.c
index d6788dd93c7b..568614edd88f 100644
--- a/drivers/irqchip/irq-realtek-rtl.c
+++ b/drivers/irqchip/irq-realtek-rtl.c
@@ -95,7 +95,8 @@ out:
* SoC interrupts are cascaded to MIPS CPU interrupts according to the
* interrupt-map in the device tree. Each SoC interrupt gets 4 bits for
* the CPU interrupt in an Interrupt Routing Register. Max 32 SoC interrupts
- * thus go into 4 IRRs.
+ * thus go into 4 IRRs. A routing value of '0' means the interrupt is left
+ * disconnected. Routing values {1..15} connect to output lines {0..14}.
*/
static int __init map_interrupts(struct device_node *node, struct irq_domain *domain)
{
@@ -134,7 +135,7 @@ static int __init map_interrupts(struct device_node *node, struct irq_domain *do
of_node_put(cpu_ictl);
cpu_int = be32_to_cpup(imap + 2);
- if (cpu_int > 7)
+ if (cpu_int > 7 || cpu_int < 2)
return -EINVAL;
if (!(mips_irqs_set & BIT(cpu_int))) {
@@ -143,7 +144,8 @@ static int __init map_interrupts(struct device_node *node, struct irq_domain *do
mips_irqs_set |= BIT(cpu_int);
}
- regs[(soc_int * 4) / 32] |= cpu_int << (soc_int * 4) % 32;
+ /* Use routing values (1..6) for CPU interrupts (2..7) */
+ regs[(soc_int * 4) / 32] |= (cpu_int - 1) << (soc_int * 4) % 32;
imap += 3;
}