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authorDaniel Hellstrom <daniel@gaisler.com>2011-04-19 23:41:26 +0000
committerDavid S. Miller <davem@davemloft.net>2011-04-21 15:31:31 -0700
commit5eb1f4fc167f5adc5f15e722e25eff6713fb3406 (patch)
tree2e1ffeb506b3d09efc5e16045283430e3e362f63 /arch/sparc/kernel
parenta481b5d0cb5d1884f16460b4846755518360f1ca (diff)
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sparc32,leon: implement genirq CPU affinity
A simple implementation of CPU affinity, the first CPU in the affinity CPU mask always takes the IRQ. Signed-off-by: Daniel Hellstrom <daniel@gaisler.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/sparc/kernel')
-rw-r--r--arch/sparc/kernel/leon_kernel.c64
1 files changed, 54 insertions, 10 deletions
diff --git a/arch/sparc/kernel/leon_kernel.c b/arch/sparc/kernel/leon_kernel.c
index d8fafeacb496..ab1458454422 100644
--- a/arch/sparc/kernel/leon_kernel.c
+++ b/arch/sparc/kernel/leon_kernel.c
@@ -99,25 +99,68 @@ static inline unsigned long get_irqmask(unsigned int irq)
return mask;
}
+#ifdef CONFIG_SMP
+static int irq_choose_cpu(const struct cpumask *affinity)
+{
+ cpumask_t mask;
+
+ cpus_and(mask, cpu_online_map, *affinity);
+ if (cpus_equal(mask, cpu_online_map) || cpus_empty(mask))
+ return 0;
+ else
+ return first_cpu(mask);
+}
+#else
+#define irq_choose_cpu(affinity) 0
+#endif
+
+static int leon_set_affinity(struct irq_data *data, const struct cpumask *dest,
+ bool force)
+{
+ unsigned long mask, oldmask, flags;
+ int oldcpu, newcpu;
+
+ mask = (unsigned long)data->chip_data;
+ oldcpu = irq_choose_cpu(data->affinity);
+ newcpu = irq_choose_cpu(dest);
+
+ if (oldcpu == newcpu)
+ goto out;
+
+ /* unmask on old CPU first before enabling on the selected CPU */
+ spin_lock_irqsave(&leon_irq_lock, flags);
+ oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(oldcpu));
+ LEON3_BYPASS_STORE_PA(LEON_IMASK(oldcpu), (oldmask & ~mask));
+ oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(newcpu));
+ LEON3_BYPASS_STORE_PA(LEON_IMASK(newcpu), (oldmask | mask));
+ spin_unlock_irqrestore(&leon_irq_lock, flags);
+out:
+ return IRQ_SET_MASK_OK;
+}
+
static void leon_unmask_irq(struct irq_data *data)
{
unsigned long mask, oldmask, flags;
+ int cpu;
mask = (unsigned long)data->chip_data;
+ cpu = irq_choose_cpu(data->affinity);
spin_lock_irqsave(&leon_irq_lock, flags);
- oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(0));
- LEON3_BYPASS_STORE_PA(LEON_IMASK(0), (oldmask | mask));
+ oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
+ LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask | mask));
spin_unlock_irqrestore(&leon_irq_lock, flags);
}
static void leon_mask_irq(struct irq_data *data)
{
unsigned long mask, oldmask, flags;
+ int cpu;
mask = (unsigned long)data->chip_data;
+ cpu = irq_choose_cpu(data->affinity);
spin_lock_irqsave(&leon_irq_lock, flags);
- oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(0));
- LEON3_BYPASS_STORE_PA(LEON_IMASK(0), (oldmask & ~mask));
+ oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
+ LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask & ~mask));
spin_unlock_irqrestore(&leon_irq_lock, flags);
}
@@ -144,12 +187,13 @@ static void leon_eoi_irq(struct irq_data *data)
}
static struct irq_chip leon_irq = {
- .name = "leon",
- .irq_startup = leon_startup_irq,
- .irq_shutdown = leon_shutdown_irq,
- .irq_mask = leon_mask_irq,
- .irq_unmask = leon_unmask_irq,
- .irq_eoi = leon_eoi_irq,
+ .name = "leon",
+ .irq_startup = leon_startup_irq,
+ .irq_shutdown = leon_shutdown_irq,
+ .irq_mask = leon_mask_irq,
+ .irq_unmask = leon_unmask_irq,
+ .irq_eoi = leon_eoi_irq,
+ .irq_set_affinity = leon_set_affinity,
};
/*