ppc32: PowerMac G5 interrupt management

The cascaded northbridge MPIC is currently dealt with a special
modified version of open_pic.c (open_pic2.c). A better mecanism
will have to be found for 2.7

arch/ppc/platforms/pmac_pic.c

@@ -34,6 +34,7 @@
 #include <asm/time.h>
 #include <asm/open_pic.h>
 #include <asm/xmon.h>
+#include <asm/pmac_feature.h>
 
 #include "pmac_pic.h"
 
@@ -363,32 +364,76 @@ static int __init enable_second_ohare(void)
 	return irqctrler->intrs[0].line;
 }
 
-void __init
-pmac_pic_init(void)
+#ifdef CONFIG_POWER4
+static irqreturn_t k2u3_action(int cpl, void *dev_id, struct pt_regs *regs)
+{
+	int irq;
+
+	irq = openpic2_get_irq(regs);
+	if (irq != -1)
+		ppc_irq_dispatch_handler(regs, irq);
+	return IRQ_HANDLED;
+}
+#endif /* CONFIG_POWER4 */
+
+void __init pmac_pic_init(void)
 {
         int i;
-        struct device_node *irqctrler;
+        struct device_node *irqctrler  = NULL;
+        struct device_node *irqctrler2 = NULL;
+	struct device_node *np;
         unsigned long addr;
 	int irq_cascade = -1;
 
 	/* We first try to detect Apple's new Core99 chipset, since mac-io
 	 * is quite different on those machines and contains an IBM MPIC2.
 	 */
-	irqctrler = find_type_devices("open-pic");
+	np = find_type_devices("open-pic");
+	while(np) {
+		if (np->parent && !strcmp(np->parent->name, "u3"))
+			irqctrler2 = np;
+		else
+			irqctrler = np;
+		np = np->next;
+	}
 	if (irqctrler != NULL)
 	{
-		printk("PowerMac using OpenPIC irq controller\n");
 		if (irqctrler->n_addrs > 0)
 		{
-			unsigned char senses[NR_IRQS];
+			unsigned char senses[128];
+
+			printk(KERN_INFO "PowerMac using OpenPIC irq controller at 0x%08x\n",
+			       irqctrler->addrs[0].address);
 
-			prom_get_irq_senses(senses, 0, NR_IRQS);
+			prom_get_irq_senses(senses, 0, 128);
 			OpenPIC_InitSenses = senses;
-			OpenPIC_NumInitSenses = NR_IRQS;
+			OpenPIC_NumInitSenses = 128;
 			ppc_md.get_irq = openpic_get_irq;
+			pmac_call_feature(PMAC_FTR_ENABLE_MPIC, irqctrler, 0, 0);
 			OpenPIC_Addr = ioremap(irqctrler->addrs[0].address,
 					       irqctrler->addrs[0].size);
 			openpic_init(0);
+
+#ifdef CONFIG_POWER4
+			if (irqctrler2 != NULL && irqctrler2->n_intrs > 0 &&
+			    irqctrler2->n_addrs > 0) {
+				printk(KERN_INFO "Slave OpenPIC at 0x%08x hooked on IRQ %d\n",
+				       irqctrler2->addrs[0].address,
+				       irqctrler2->intrs[0].line);
+				pmac_call_feature(PMAC_FTR_ENABLE_MPIC, irqctrler2, 0, 0);
+				OpenPIC2_Addr = ioremap(irqctrler2->addrs[0].address,
+							irqctrler2->addrs[0].size);
+				prom_get_irq_senses(senses, PMAC_OPENPIC2_OFFSET,
+						    PMAC_OPENPIC2_OFFSET+128);
+				OpenPIC_InitSenses = senses;
+				OpenPIC_NumInitSenses = 128;
+				openpic2_init(PMAC_OPENPIC2_OFFSET);
+				if (request_irq(irqctrler2->intrs[0].line, k2u3_action, 0,
+						"U3->K2 Cascade", NULL))
+					printk("Unable to get OpenPIC IRQ for cascade\n");
+			}
+#endif /* CONFIG_POWER4 */
+
 #ifdef CONFIG_XMON
 			{
 				struct device_node* pswitch;

arch/ppc/syslib/Makefile

@@ -31,6 +31,7 @@ obj-$(CONFIG_PCI)		+= qspan_pci.o i8259.o
 endif
 obj-$(CONFIG_PPC_OF)		+= prom_init.o prom.o of_device.o
 obj-$(CONFIG_PPC_PMAC)		+= open_pic.o indirect_pci.o
+obj-$(CONFIG_POWER4)		+= open_pic2.o
 obj-$(CONFIG_PPC_CHRP)		+= open_pic.o indirect_pci.o i8259.o
 obj-$(CONFIG_PPC_PREP)		+= open_pic.o indirect_pci.o i8259.o
 obj-$(CONFIG_ADIR)		+= i8259.o indirect_pci.o pci_auto.o \

arch/ppc/syslib/open_pic.c

@@ -610,12 +610,15 @@ void openpic_request_IPIs(void)
 
 void __devinit do_openpic_setup_cpu(void)
 {
+#ifdef CONFIG_IRQ_ALL_CPUS
  	int i;
-	u32 msk = 1 << smp_hw_index[smp_processor_id()];
-
+	u32 msk;
+#endif
 	spin_lock(&openpic_setup_lock);
 
 #ifdef CONFIG_IRQ_ALL_CPUS
+	msk = 1 << smp_hw_index[smp_processor_id()];
+
  	/* let the openpic know we want intrs. default affinity
  	 * is 0xffffffff until changed via /proc
  	 * That's how it's done on x86. If we want it differently, then
@@ -788,15 +791,25 @@ static void openpic_set_sense(u_int irq, int sense)
  */
 static void openpic_ack_irq(unsigned int irq_nr)
 {
+#ifdef __SLOW_VERSION__
 	openpic_disable_irq(irq_nr);
 	openpic_eoi();
+#else
+	if ((irq_desc[irq_nr].status & IRQ_LEVEL) == 0)
+		openpic_eoi();
+#endif
 }
 
 static void openpic_end_irq(unsigned int irq_nr)
 {
+#ifdef __SLOW_VERSION__
 	if (!(irq_desc[irq_nr].status & (IRQ_DISABLED|IRQ_INPROGRESS))
 	    && irq_desc[irq_nr].action)
 		openpic_enable_irq(irq_nr);
+#else
+	if ((irq_desc[irq_nr].status & IRQ_LEVEL) != 0)
+		openpic_eoi();
+#endif
 }
 
 static void openpic_set_affinity(unsigned int irq_nr, unsigned long cpumask)

include/asm-ppc/open_pic.h

@@ -21,8 +21,8 @@
  *  Non-offset'ed vector numbers
  */
 
-#define OPENPIC_VEC_TIMER	64	/* and up */
-#define OPENPIC_VEC_IPI		72	/* and up */
+#define OPENPIC_VEC_TIMER	110	/* and up */
+#define OPENPIC_VEC_IPI		118	/* and up */
 #define OPENPIC_VEC_SPURIOUS	127
 
 /* OpenPIC IRQ controller structure */
@@ -51,6 +51,7 @@ extern void openpic_setup_ISU(int isu_num, unsigned long addr);
 extern void openpic_cause_IPI(u_int ipi, u_int cpumask);
 extern void smp_openpic_message_pass(int target, int msg, unsigned long data,
 				     int wait);
+extern void openpic_set_k2_cascade(int irq);
 
 extern inline int openpic_to_irq(int irq)
 {
@@ -64,5 +65,25 @@ extern inline int openpic_to_irq(int irq)
 		return 0;
 	}
 }
-/*extern int open_pic_irq_offset;*/
+/* Support for second openpic on G5 macs */
+
+// FIXME: To be replaced by sane cascaded controller management */
+
+#define PMAC_OPENPIC2_OFFSET	128
+
+#define OPENPIC2_VEC_TIMER	110	/* and up */
+#define OPENPIC2_VEC_IPI	118	/* and up */
+#define OPENPIC2_VEC_SPURIOUS	127
+
+
+extern void* OpenPIC2_Addr;
+
+/* Exported functions */
+extern void openpic2_set_sources(int first_irq, int num_irqs, void *isr);
+extern void openpic2_init(int linux_irq_offset);
+extern void openpic2_init_nmi_irq(u_int irq);
+extern u_int openpic2_irq(void);
+extern void openpic2_eoi(void);
+extern int openpic2_get_irq(struct pt_regs *regs);
+extern void openpic2_setup_ISU(int isu_num, unsigned long addr);
 #endif /* _PPC_KERNEL_OPEN_PIC_H */