[POWERPC] MPIC: support more than 256 sources

Allow more than the default 256 MPIC sources. Allocates a new flag
(MPIC_LARGE_VECTORS) to be used by platform code when instantiating
the mpic.

I picked 11 bits worth right now since it would cover the number of
sources on any hardware I have seen. It can always be increased later
if needed.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 42 insertions, 22 deletions

diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 62262f2a4a83..aa701cc27ecc 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -496,13 +496,18 @@ static void __init mpic_scan_ht_pics(struct mpic *mpic)
 static struct mpic *mpic_find(unsigned int irq, unsigned int *is_ipi)
 {
         unsigned int src = mpic_irq_to_hw(irq);
+        struct mpic *mpic;
 
         if (irq < NUM_ISA_INTERRUPTS)
                 return NULL;
+
+        mpic = irq_desc[irq].chip_data;
+
         if (is_ipi)
-                *is_ipi = (src >= MPIC_VEC_IPI_0 && src <= MPIC_VEC_IPI_3);
+                *is_ipi = (src >= mpic->ipi_vecs[0] &&
+                           src <= mpic->ipi_vecs[3]);
 
-        return irq_desc[irq].chip_data;
+        return mpic;
 }
 
 /* Convert a cpu mask from logical to physical cpu numbers. */
@@ -540,7 +545,11 @@ static inline void mpic_eoi(struct mpic *mpic)
 #ifdef CONFIG_SMP
 static irqreturn_t mpic_ipi_action(int irq, void *dev_id)
 {
-        smp_message_recv(mpic_irq_to_hw(irq) - MPIC_VEC_IPI_0);
+        struct mpic *mpic;
+
+        mpic = mpic_find(irq, NULL);
+        smp_message_recv(mpic_irq_to_hw(irq) - mpic->ipi_vecs[0]);
+
         return IRQ_HANDLED;
 }
 #endif /* CONFIG_SMP */
@@ -663,7 +672,7 @@ static void mpic_end_ht_irq(unsigned int irq)
 static void mpic_unmask_ipi(unsigned int irq)
 {
         struct mpic *mpic = mpic_from_ipi(irq);
-        unsigned int src = mpic_irq_to_hw(irq) - MPIC_VEC_IPI_0;
+        unsigned int src = mpic_irq_to_hw(irq) - mpic->ipi_vecs[0];
 
         DBG("%s: enable_ipi: %d (ipi %d)\n", mpic->name, irq, src);
         mpic_ipi_write(src, mpic_ipi_read(src) & ~MPIC_VECPRI_MASK);
@@ -807,11 +816,11 @@ static int mpic_host_map(struct irq_host *h, unsigned int virq,
 
         DBG("mpic: map virq %d, hwirq 0x%lx\n", virq, hw);
 
-        if (hw == MPIC_VEC_SPURRIOUS)
+        if (hw == mpic->spurious_vec)
                 return -EINVAL;
 
 #ifdef CONFIG_SMP
-        else if (hw >= MPIC_VEC_IPI_0) {
+        else if (hw >= mpic->ipi_vecs[0]) {
                 WARN_ON(!(mpic->flags & MPIC_PRIMARY));
 
                 DBG("mpic: mapping as IPI\n");
@@ -904,6 +913,7 @@ struct mpic * __init mpic_alloc(struct device_node *node,
         u32             reg;
         const char      *vers;
         int             i;
+        int             intvec_top;
         u64             paddr = phys_addr;
 
         mpic = alloc_bootmem(sizeof(struct mpic));
@@ -914,9 +924,9 @@ struct mpic * __init mpic_alloc(struct device_node *node,
         mpic->name = name;
         mpic->of_node = of_node_get(node);
 
-        mpic->irqhost = irq_alloc_host(IRQ_HOST_MAP_LINEAR, 256,
+        mpic->irqhost = irq_alloc_host(IRQ_HOST_MAP_LINEAR, isu_size,
                                        &mpic_host_ops,
-                                       MPIC_VEC_SPURRIOUS);
+                                       flags & MPIC_LARGE_VECTORS ? 2048 : 256);
         if (mpic->irqhost == NULL) {
                 of_node_put(node);
                 return NULL;
@@ -944,6 +954,21 @@ struct mpic * __init mpic_alloc(struct device_node *node,
         mpic->irq_count = irq_count;
         mpic->num_sources = 0; /* so far */
 
+        if (flags & MPIC_LARGE_VECTORS)
+                intvec_top = 2047;
+        else
+                intvec_top = 255;
+
+        mpic->timer_vecs[0] = intvec_top - 8;
+        mpic->timer_vecs[1] = intvec_top - 7;
+        mpic->timer_vecs[2] = intvec_top - 6;
+        mpic->timer_vecs[3] = intvec_top - 5;
+        mpic->ipi_vecs[0]   = intvec_top - 4;
+        mpic->ipi_vecs[1]   = intvec_top - 3;
+        mpic->ipi_vecs[2]   = intvec_top - 2;
+        mpic->ipi_vecs[3]   = intvec_top - 1;
+        mpic->spurious_vec  = intvec_top;
+
         /* Check for "big-endian" in device-tree */
         if (node && get_property(node, "big-endian", NULL) != NULL)
                 mpic->flags |= MPIC_BIG_ENDIAN;
@@ -1084,11 +1109,6 @@ void __init mpic_init(struct mpic *mpic)
         int i;
 
         BUG_ON(mpic->num_sources == 0);
-        WARN_ON(mpic->num_sources > MPIC_VEC_IPI_0);
-
-        /* Sanitize source count */
-        if (mpic->num_sources > MPIC_VEC_IPI_0)
-                mpic->num_sources = MPIC_VEC_IPI_0;
 
         printk(KERN_INFO "mpic: Initializing for %d sources\n", mpic->num_sources);
 
@@ -1104,7 +1124,7 @@ void __init mpic_init(struct mpic *mpic)
                            i * MPIC_INFO(TIMER_STRIDE) +
                            MPIC_INFO(TIMER_VECTOR_PRI),
                            MPIC_VECPRI_MASK |
-                           (MPIC_VEC_TIMER_0 + i));
+                           (mpic->timer_vecs[0] + i));
         }
 
         /* Initialize IPIs to our reserved vectors and mark them disabled for now */
@@ -1113,7 +1133,7 @@ void __init mpic_init(struct mpic *mpic)
                 mpic_ipi_write(i,
                                MPIC_VECPRI_MASK |
                                (10 << MPIC_VECPRI_PRIORITY_SHIFT) |
-                               (MPIC_VEC_IPI_0 + i));
+                               (mpic->ipi_vecs[0] + i));
         }
 
         /* Initialize interrupt sources */
@@ -1136,8 +1156,8 @@ void __init mpic_init(struct mpic *mpic)
                                1 << hard_smp_processor_id());
         }
         
-        /* Init spurrious vector */
-        mpic_write(mpic->gregs, MPIC_INFO(GREG_SPURIOUS), MPIC_VEC_SPURRIOUS);
+        /* Init spurious vector */
+        mpic_write(mpic->gregs, MPIC_INFO(GREG_SPURIOUS), mpic->spurious_vec);
 
         /* Disable 8259 passthrough, if supported */
         if (!(mpic->flags & MPIC_NO_PTHROU_DIS))
@@ -1184,9 +1204,9 @@ void mpic_irq_set_priority(unsigned int irq, unsigned int pri)
 
         spin_lock_irqsave(&mpic_lock, flags);
         if (is_ipi) {
-                reg = mpic_ipi_read(src - MPIC_VEC_IPI_0) &
+                reg = mpic_ipi_read(src - mpic->ipi_vecs[0]) &
                         ~MPIC_VECPRI_PRIORITY_MASK;
-                mpic_ipi_write(src - MPIC_VEC_IPI_0,
+                mpic_ipi_write(src - mpic->ipi_vecs[0],
                                reg | (pri << MPIC_VECPRI_PRIORITY_SHIFT));
         } else {
                 reg = mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI))
@@ -1207,7 +1227,7 @@ unsigned int mpic_irq_get_priority(unsigned int irq)
 
         spin_lock_irqsave(&mpic_lock, flags);
         if (is_ipi)
-                reg = mpic_ipi_read(src = MPIC_VEC_IPI_0);
+                reg = mpic_ipi_read(src = mpic->ipi_vecs[0]);
         else
                 reg = mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI));
         spin_unlock_irqrestore(&mpic_lock, flags);
@@ -1313,7 +1333,7 @@ unsigned int mpic_get_one_irq(struct mpic *mpic)
 #ifdef DEBUG_LOW
         DBG("%s: get_one_irq(): %d\n", mpic->name, src);
 #endif
-        if (unlikely(src == MPIC_VEC_SPURRIOUS))
+        if (unlikely(src == mpic->spurious_vec))
                 return NO_IRQ;
         return irq_linear_revmap(mpic->irqhost, src);
 }
@@ -1345,7 +1365,7 @@ void mpic_request_ipis(void)
 
         for (i = 0; i < 4; i++) {
                 unsigned int vipi = irq_create_mapping(mpic->irqhost,
-                                                       MPIC_VEC_IPI_0 + i);
+                                                       mpic->ipi_vecs[0] + i);
                 if (vipi == NO_IRQ) {
                         printk(KERN_ERR "Failed to map IPI %d\n", i);
                         break;