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authorDaniel Hellstrom <daniel@gaisler.com>2011-04-19 23:41:22 +0000
committerDavid S. Miller <davem@davemloft.net>2011-04-21 15:31:29 -0700
commit4c6773c3954cb1192f70a63e2dc61adc55bb0948 (patch)
tree959f841e0ac17fc3e4796f9ee7582ea1a02627c3 /arch/sparc/kernel/leon_kernel.c
parentd61a38b2ced149c00898833ccd3ea0433db8ae7d (diff)
downloadop-kernel-dev-4c6773c3954cb1192f70a63e2dc61adc55bb0948.zip
op-kernel-dev-4c6773c3954cb1192f70a63e2dc61adc55bb0948.tar.gz
sparc32,leon: add support for extended interrupt controller
The extended IRQ controller gives the LEON 16 more IRQs. The patch installs a custom handler for the exetended controller IRQ, where a register is read and the "real" IRQ causing IRQ is determined. 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/leon_kernel.c')
-rw-r--r--arch/sparc/kernel/leon_kernel.c95
1 files changed, 71 insertions, 24 deletions
diff --git a/arch/sparc/kernel/leon_kernel.c b/arch/sparc/kernel/leon_kernel.c
index 390e469..210f4a0 100644
--- a/arch/sparc/kernel/leon_kernel.c
+++ b/arch/sparc/kernel/leon_kernel.c
@@ -19,6 +19,7 @@
#include <asm/leon_amba.h>
#include <asm/traps.h>
#include <asm/cacheflush.h>
+#include <asm/smp.h>
#include "prom.h"
#include "irq.h"
@@ -36,37 +37,51 @@ static DEFINE_SPINLOCK(leon_irq_lock);
unsigned long leon3_gptimer_irq; /* interrupt controller irq number */
unsigned long leon3_gptimer_idx; /* Timer Index (0..6) within Timer Core */
unsigned int sparc_leon_eirq;
-#define LEON_IMASK ((&leon3_irqctrl_regs->mask[0]))
+#define LEON_IMASK (&leon3_irqctrl_regs->mask[0])
+#define LEON_IACK (&leon3_irqctrl_regs->iclear)
+#define LEON_DO_ACK_HW 1
-/* Return the IRQ of the pending IRQ on the extended IRQ controller */
-int sparc_leon_eirq_get(int eirq, int cpu)
+/* Return the last ACKed IRQ by the Extended IRQ controller. It has already
+ * been (automatically) ACKed when the CPU takes the trap.
+ */
+static inline unsigned int leon_eirq_get(int cpu)
{
return LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->intid[cpu]) & 0x1f;
}
-irqreturn_t sparc_leon_eirq_isr(int dummy, void *dev_id)
+/* Handle one or multiple IRQs from the extended interrupt controller */
+static void leon_handle_ext_irq(unsigned int irq, struct irq_desc *desc)
{
- printk(KERN_ERR "sparc_leon_eirq_isr: ERROR EXTENDED IRQ\n");
- return IRQ_HANDLED;
+ unsigned int eirq;
+ int cpu = hard_smp_processor_id();
+
+ eirq = leon_eirq_get(cpu);
+ if ((eirq & 0x10) && irq_map[eirq]->irq) /* bit4 tells if IRQ happened */
+ generic_handle_irq(irq_map[eirq]->irq);
}
/* The extended IRQ controller has been found, this function registers it */
-void sparc_leon_eirq_register(int eirq)
+void leon_eirq_setup(unsigned int eirq)
{
- int irq;
+ unsigned long mask, oldmask;
+ unsigned int veirq;
- /* Register a "BAD" handler for this interrupt, it should never happen */
- irq = request_irq(eirq, sparc_leon_eirq_isr,
- (IRQF_DISABLED | SA_STATIC_ALLOC), "extirq", NULL);
-
- if (irq) {
- printk(KERN_ERR
- "sparc_leon_eirq_register: unable to attach IRQ%d\n",
- eirq);
- } else {
- sparc_leon_eirq = eirq;
+ if (eirq < 1 || eirq > 0xf) {
+ printk(KERN_ERR "LEON EXT IRQ NUMBER BAD: %d\n", eirq);
+ return;
}
+ veirq = leon_build_device_irq(eirq, leon_handle_ext_irq, "extirq", 0);
+
+ /*
+ * Unmask the Extended IRQ, the IRQs routed through the Ext-IRQ
+ * controller have a mask-bit of their own, so this is safe.
+ */
+ irq_link(veirq);
+ mask = 1 << eirq;
+ oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK);
+ LEON3_BYPASS_STORE_PA(LEON_IMASK, (oldmask | mask));
+ sparc_leon_eirq = eirq;
}
static inline unsigned long get_irqmask(unsigned int irq)
@@ -119,16 +134,33 @@ static void leon_shutdown_irq(struct irq_data *data)
irq_unlink(data->irq);
}
+/* Used by external level sensitive IRQ handlers on the LEON: ACK IRQ ctrl */
+static void leon_eoi_irq(struct irq_data *data)
+{
+ unsigned long mask = (unsigned long)data->chip_data;
+
+ if (mask & LEON_DO_ACK_HW)
+ LEON3_BYPASS_STORE_PA(LEON_IACK, mask & ~LEON_DO_ACK_HW);
+}
+
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,
};
-static unsigned int leon_build_device_irq(struct platform_device *op,
- unsigned int real_irq)
+/*
+ * Build a LEON IRQ for the edge triggered LEON IRQ controller:
+ * Edge (normal) IRQ - handle_simple_irq, ack=DONT-CARE, never ack
+ * Level IRQ (PCI|Level-GPIO) - handle_fasteoi_irq, ack=1, ack after ISR
+ * Per-CPU Edge - handle_percpu_irq, ack=0
+ */
+unsigned int leon_build_device_irq(unsigned int real_irq,
+ irq_flow_handler_t flow_handler,
+ const char *name, int do_ack)
{
unsigned int irq;
unsigned long mask;
@@ -142,17 +174,26 @@ static unsigned int leon_build_device_irq(struct platform_device *op,
if (irq == 0)
goto out;
+ if (do_ack)
+ mask |= LEON_DO_ACK_HW;
+
irq_set_chip_and_handler_name(irq, &leon_irq,
- handle_simple_irq, "edge");
+ flow_handler, name);
irq_set_chip_data(irq, (void *)mask);
out:
return irq;
}
+static unsigned int _leon_build_device_irq(struct platform_device *op,
+ unsigned int real_irq)
+{
+ return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
+}
+
void __init leon_init_timers(irq_handler_t counter_fn)
{
- int irq;
+ int irq, eirq;
struct device_node *rootnp, *np, *nnp;
struct property *pp;
int len;
@@ -262,11 +303,17 @@ void __init leon_init_timers(irq_handler_t counter_fn)
icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[cpu/8]);
icsel = (icsel >> ((7 - (cpu&0x7)) * 4)) & 0xf;
leon3_irqctrl_regs += icsel;
+
+ /* Probe extended IRQ controller */
+ eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
+ >> 16) & 0xf;
+ if (eirq != 0)
+ leon_eirq_setup(eirq);
} else {
goto bad;
}
- irq = leon_build_device_irq(NULL, leon3_gptimer_irq + leon3_gptimer_idx);
+ irq = _leon_build_device_irq(NULL, leon3_gptimer_irq+leon3_gptimer_idx);
err = request_irq(irq, counter_fn, IRQF_TIMER, "timer", NULL);
if (err) {
@@ -394,7 +441,7 @@ void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
void __init leon_init_IRQ(void)
{
sparc_irq_config.init_timers = leon_init_timers;
- sparc_irq_config.build_device_irq = leon_build_device_irq;
+ sparc_irq_config.build_device_irq = _leon_build_device_irq;
BTFIXUPSET_CALL(clear_clock_irq, leon_clear_clock_irq,
BTFIXUPCALL_NORM);
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