ns9xxx: add support for irq priorisation
prio2irq(0) is the highest prioritized interrupt. For now there is no
binary change intended.
If you intend to change the priorisation, you have to assert:
∀ x ∈ {0, 1, ⋯ 31}: (irq2prio ∘ prio2irq)(x) = x
Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
diff --git a/arch/arm/mach-ns9xxx/irq.c b/arch/arm/mach-ns9xxx/irq.c
index 7ddc8fd..36e5835 100644
--- a/arch/arm/mach-ns9xxx/irq.c
+++ b/arch/arm/mach-ns9xxx/irq.c
@@ -19,12 +19,17 @@
#include "generic.h"
+/* simple interrupt prio table: prio(x) < prio(y) <=> x < y */
+#define irq2prio(i) (i)
+#define prio2irq(p) (p)
+
static void ns9xxx_mask_irq(unsigned int irq)
{
/* XXX: better use cpp symbols */
- u32 ic = __raw_readl(SYS_IC(irq / 4));
- ic &= ~(1 << (7 + 8 * (3 - (irq & 3))));
- __raw_writel(ic, SYS_IC(irq / 4));
+ int prio = irq2prio(irq);
+ u32 ic = __raw_readl(SYS_IC(prio / 4));
+ ic &= ~(1 << (7 + 8 * (3 - (prio & 3))));
+ __raw_writel(ic, SYS_IC(prio / 4));
}
static void ns9xxx_ack_irq(unsigned int irq)
@@ -41,9 +46,10 @@
static void ns9xxx_unmask_irq(unsigned int irq)
{
/* XXX: better use cpp symbols */
- u32 ic = __raw_readl(SYS_IC(irq / 4));
- ic |= 1 << (7 + 8 * (3 - (irq & 3)));
- __raw_writel(ic, SYS_IC(irq / 4));
+ int prio = irq2prio(irq);
+ u32 ic = __raw_readl(SYS_IC(prio / 4));
+ ic |= 1 << (7 + 8 * (3 - (prio & 3)));
+ __raw_writel(ic, SYS_IC(prio / 4));
}
static struct irq_chip ns9xxx_chip = {
@@ -96,14 +102,14 @@
/* disable all IRQs */
for (i = 0; i < 8; ++i)
- __raw_writel((4 * i) << 24 | (4 * i + 1) << 16 |
- (4 * i + 2) << 8 | (4 * i + 3), SYS_IC(i));
+ __raw_writel(prio2irq(4 * i) << 24 |
+ prio2irq(4 * i + 1) << 16 |
+ prio2irq(4 * i + 2) << 8 |
+ prio2irq(4 * i + 3),
+ SYS_IC(i));
- /* simple interrupt prio table:
- * prio(x) < prio(y) <=> x < y
- */
for (i = 0; i < 32; ++i)
- __raw_writel(i, SYS_IVA(i));
+ __raw_writel(prio2irq(i), SYS_IVA(i));
for (i = 0; i <= 31; ++i) {
set_irq_chip(i, &ns9xxx_chip);