[POWERPC] Add new interrupt mapping core and change platforms to use it

This adds the new irq remapper core and removes the old one.  Because
there are some fundamental conflicts with the old code, like the value
of NO_IRQ which I'm now setting to 0 (as per discussions with Linus),
etc..., this commit also changes the relevant platform and driver code
over to use the new remapper (so as not to cause difficulties later
in bisecting).

This patch removes the old pre-parsing of the open firmware interrupt
tree along with all the bogus assumptions it made to try to renumber
interrupts according to the platform. This is all to be handled by the
new code now.

For the pSeries XICS interrupt controller, a single remapper host is
created for the whole machine regardless of how many interrupt
presentation and source controllers are found, and it's set to match
any device node that isn't a 8259.  That works fine on pSeries and
avoids having to deal with some of the complexities of split source
controllers vs. presentation controllers in the pSeries device trees.

The powerpc i8259 PIC driver now always requests the legacy interrupt
range. It also has the feature of being able to match any device node
(including NULL) if passed no device node as an input. That will help
porting over platforms with broken device-trees like Pegasos who don't
have a proper interrupt tree.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 129 insertions, 117 deletions

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 476b564a208..54a52437265 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -76,6 +76,9 @@
 #define DBG(fmt...)
 #endif
 
+/* move those away to a .h */
+extern void smp_init_pseries_mpic(void);
+extern void smp_init_pseries_xics(void);
 extern void find_udbg_vterm(void);
 
 int fwnmi_active;  /* TRUE if an FWNMI handler is present */
@@ -83,7 +86,7 @@ int fwnmi_active;  /* TRUE if an FWNMI handler is present */
 static void pseries_shared_idle_sleep(void);
 static void pseries_dedicated_idle_sleep(void);
 
-struct mpic *pSeries_mpic;
+static struct device_node *pSeries_mpic_node;
 
 static void pSeries_show_cpuinfo(struct seq_file *m)
 {
@@ -118,78 +121,92 @@ static void __init fwnmi_init(void)
 		fwnmi_active = 1;
 }
 
-void pSeries_8259_cascade(unsigned int irq, struct irq_desc *desc,
+void pseries_8259_cascade(unsigned int irq, struct irq_desc *desc,
 			  struct pt_regs *regs)
 {
-	unsigned int max = 100;
-
-	while(max--) {
-		int cascade_irq = i8259_irq(regs);
-		if (max == 99)
-			desc->chip->eoi(irq);
-		if (cascade_irq < 0)
-			break;
+	unsigned int cascade_irq = i8259_irq(regs);
+	if (cascade_irq != NO_IRQ)
 		generic_handle_irq(cascade_irq, regs);
-	};
+	desc->chip->eoi(irq);
 }
 
-static void __init pSeries_init_mpic(void)
+static void __init pseries_mpic_init_IRQ(void)
 {
+	struct device_node *np, *old, *cascade = NULL;
         unsigned int *addrp;
-	struct device_node *np;
 	unsigned long intack = 0;
-
-	/* All ISUs are setup, complete initialization */
-	mpic_init(pSeries_mpic);
-
-	/* Check what kind of cascade ACK we have */
-        if (!(np = of_find_node_by_name(NULL, "pci"))
-            || !(addrp = (unsigned int *)
-                 get_property(np, "8259-interrupt-acknowledge", NULL)))
-                printk(KERN_ERR "Cannot find pci to get ack address\n");
-        else
-		intack = addrp[prom_n_addr_cells(np)-1];
-	of_node_put(np);
-
-	/* Setup the legacy interrupts & controller */
-	i8259_init(intack, 0);
-
-	/* Hook cascade to mpic */
-	set_irq_chained_handler(NUM_ISA_INTERRUPTS, pSeries_8259_cascade);
-}
-
-static void __init pSeries_setup_mpic(void)
-{
 	unsigned int *opprop;
 	unsigned long openpic_addr = 0;
-        unsigned char senses[NR_IRQS - NUM_ISA_INTERRUPTS];
-        struct device_node *root;
-	int irq_count;
+	unsigned int cascade_irq;
+	int naddr, n, i, opplen;
+	struct mpic *mpic;
 
-	/* Find the Open PIC if present */
-	root = of_find_node_by_path("/");
-	opprop = (unsigned int *) get_property(root, "platform-open-pic", NULL);
+	np = of_find_node_by_path("/");
+	naddr = prom_n_addr_cells(np);
+	opprop = (unsigned int *) get_property(np, "platform-open-pic", &opplen);
 	if (opprop != 0) {
-		int n = prom_n_addr_cells(root);
-
-		for (openpic_addr = 0; n > 0; --n)
-			openpic_addr = (openpic_addr << 32) + *opprop++;
+		openpic_addr = of_read_number(opprop, naddr);
 		printk(KERN_DEBUG "OpenPIC addr: %lx\n", openpic_addr);
 	}
-	of_node_put(root);
+	of_node_put(np);
 
 	BUG_ON(openpic_addr == 0);
 
-	/* Get the sense values from OF */
-	prom_get_irq_senses(senses, NUM_ISA_INTERRUPTS, NR_IRQS);
-	
 	/* Setup the openpic driver */
-	irq_count = NR_IRQS - NUM_ISA_INTERRUPTS - 4; /* leave room for IPIs */
-	pSeries_mpic = mpic_alloc(openpic_addr, MPIC_PRIMARY,
-				  16, 16, irq_count, /* isu size, irq offset, irq count */ 
-				  NR_IRQS - 4, /* ipi offset */
-				  senses, irq_count, /* sense & sense size */
-				  " MPIC     ");
+	mpic = mpic_alloc(pSeries_mpic_node, openpic_addr,
+			  MPIC_PRIMARY,
+			  16, 250, /* isu size, irq count */
+			  " MPIC     ");
+	BUG_ON(mpic == NULL);
+
+	/* Add ISUs */
+	opplen /= sizeof(u32);
+	for (n = 0, i = naddr; i < opplen; i += naddr, n++) {
+		unsigned long isuaddr = of_read_number(opprop + i, naddr);
+		mpic_assign_isu(mpic, n, isuaddr);
+	}
+
+	/* All ISUs are setup, complete initialization */
+	mpic_init(mpic);
+
+	/* Look for cascade */
+	for_each_node_by_type(np, "interrupt-controller")
+		if (device_is_compatible(np, "chrp,iic")) {
+			cascade = np;
+			break;
+		}
+	if (cascade == NULL)
+		return;
+
+	cascade_irq = irq_of_parse_and_map(cascade, 0);
+	if (cascade == NO_IRQ) {
+		printk(KERN_ERR "xics: failed to map cascade interrupt");
+		return;
+	}
+
+	/* Check ACK type */
+	for (old = of_node_get(cascade); old != NULL ; old = np) {
+		np = of_get_parent(old);
+		of_node_put(old);
+		if (np == NULL)
+			break;
+		if (strcmp(np->name, "pci") != 0)
+			continue;
+		addrp = (u32 *)get_property(np, "8259-interrupt-acknowledge",
+					    NULL);
+		if (addrp == NULL)
+			continue;
+		naddr = prom_n_addr_cells(np);
+		intack = addrp[naddr-1];
+		if (naddr > 1)
+			intack |= ((unsigned long)addrp[naddr-2]) << 32;
+	}
+	if (intack)
+		printk(KERN_DEBUG "mpic: PCI 8259 intack at 0x%016lx\n",
+		       intack);
+	i8259_init(cascade, intack);
+	of_node_put(cascade);
+	set_irq_chained_handler(cascade_irq, pseries_8259_cascade);
 }
 
 static void pseries_lpar_enable_pmcs(void)
@@ -207,21 +224,67 @@ static void pseries_lpar_enable_pmcs(void)
 		get_lppaca()->pmcregs_in_use = 1;
 }
 
-static void __init pSeries_setup_arch(void)
+#ifdef CONFIG_KEXEC
+static void pseries_kexec_cpu_down_mpic(int crash_shutdown, int secondary)
 {
-	/* Fixup ppc_md depending on the type of interrupt controller */
-	if (ppc64_interrupt_controller == IC_OPEN_PIC) {
-		ppc_md.init_IRQ       = pSeries_init_mpic;
-		ppc_md.get_irq        = mpic_get_irq;
-		/* Allocate the mpic now, so that find_and_init_phbs() can
-		 * fill the ISUs */
-		pSeries_setup_mpic();
-	} else
-		ppc_md.init_IRQ       = xics_init_IRQ;
+	mpic_teardown_this_cpu(secondary);
+}
 
+static void pseries_kexec_cpu_down_xics(int crash_shutdown, int secondary)
+{
+	/* Don't risk a hypervisor call if we're crashing */
+	if (firmware_has_feature(FW_FEATURE_SPLPAR) && !crash_shutdown) {
+		unsigned long vpa = __pa(get_lppaca());
+
+		if (unregister_vpa(hard_smp_processor_id(), vpa)) {
+			printk("VPA deregistration of cpu %u (hw_cpu_id %d) "
+					"failed\n", smp_processor_id(),
+					hard_smp_processor_id());
+		}
+	}
+	xics_teardown_cpu(secondary);
+}
+#endif /* CONFIG_KEXEC */
+
+static void __init pseries_discover_pic(void)
+{
+	struct device_node *np;
+	char *typep;
+
+	for (np = NULL; (np = of_find_node_by_name(np,
+						   "interrupt-controller"));) {
+		typep = (char *)get_property(np, "compatible", NULL);
+		if (strstr(typep, "open-pic")) {
+			pSeries_mpic_node = of_node_get(np);
+			ppc_md.init_IRQ       = pseries_mpic_init_IRQ;
+			ppc_md.get_irq        = mpic_get_irq;
+#ifdef CONFIG_KEXEC
+			ppc_md.kexec_cpu_down = pseries_kexec_cpu_down_mpic;
+#endif
 #ifdef CONFIG_SMP
-	smp_init_pSeries();
+			smp_init_pseries_mpic();
 #endif
+			return;
+		} else if (strstr(typep, "ppc-xicp")) {
+			ppc_md.init_IRQ       = xics_init_IRQ;
+#ifdef CONFIG_KEXEC
+			ppc_md.kexec_cpu_down = pseries_kexec_cpu_down_xics;
+#endif
+#ifdef CONFIG_SMP
+			smp_init_pseries_xics();
+#endif
+			return;
+		}
+	}
+	printk(KERN_ERR "pSeries_discover_pic: failed to recognize"
+	       " interrupt-controller\n");
+}
+
+static void __init pSeries_setup_arch(void)
+{
+	/* Discover PIC type and setup ppc_md accordingly */
+	pseries_discover_pic();
+
 	/* openpic global configuration register (64-bit format). */
 	/* openpic Interrupt Source Unit pointer (64-bit format). */
 	/* python0 facility area (mmio) (64-bit format) REAL address. */
@@ -273,33 +336,6 @@ static int __init pSeries_init_panel(void)
 }
 arch_initcall(pSeries_init_panel);
 
-static  void __init pSeries_discover_pic(void)
-{
-	struct device_node *np;
-	char *typep;
-
-	/*
-	 * Setup interrupt mapping options that are needed for finish_device_tree
-	 * to properly parse the OF interrupt tree & do the virtual irq mapping
-	 */
-	__irq_offset_value = NUM_ISA_INTERRUPTS;
-	ppc64_interrupt_controller = IC_INVALID;
-	for (np = NULL; (np = of_find_node_by_name(np, "interrupt-controller"));) {
-		typep = (char *)get_property(np, "compatible", NULL);
-		if (strstr(typep, "open-pic")) {
-			ppc64_interrupt_controller = IC_OPEN_PIC;
-			break;
-		} else if (strstr(typep, "ppc-xicp")) {
-			ppc64_interrupt_controller = IC_PPC_XIC;
-			break;
-		}
-	}
-	if (ppc64_interrupt_controller == IC_INVALID)
-		printk("pSeries_discover_pic: failed to recognize"
-			" interrupt-controller\n");
-
-}
-
 static void pSeries_mach_cpu_die(void)
 {
 	local_irq_disable();
@@ -342,8 +378,6 @@ static void __init pSeries_init_early(void)
 
 	iommu_init_early_pSeries();
 
-	pSeries_discover_pic();
-
 	DBG(" <- pSeries_init_early()\n");
 }
 
@@ -515,27 +549,6 @@ static int pSeries_pci_probe_mode(struct pci_bus *bus)
 	return PCI_PROBE_NORMAL;
 }
 
-#ifdef CONFIG_KEXEC
-static void pseries_kexec_cpu_down(int crash_shutdown, int secondary)
-{
-	/* Don't risk a hypervisor call if we're crashing */
-	if (firmware_has_feature(FW_FEATURE_SPLPAR) && !crash_shutdown) {
-		unsigned long vpa = __pa(get_lppaca());
-
-		if (unregister_vpa(hard_smp_processor_id(), vpa)) {
-			printk("VPA deregistration of cpu %u (hw_cpu_id %d) "
-					"failed\n", smp_processor_id(),
-					hard_smp_processor_id());
-		}
-	}
-
-	if (ppc64_interrupt_controller == IC_OPEN_PIC)
-		mpic_teardown_this_cpu(secondary);
-	else
-		xics_teardown_cpu(secondary);
-}
-#endif
-
 define_machine(pseries) {
 	.name			= "pSeries",
 	.probe			= pSeries_probe,
@@ -560,7 +573,6 @@ define_machine(pseries) {
 	.system_reset_exception = pSeries_system_reset_exception,
 	.machine_check_exception = pSeries_machine_check_exception,
 #ifdef CONFIG_KEXEC
-	.kexec_cpu_down		= pseries_kexec_cpu_down,
 	.machine_kexec		= default_machine_kexec,
 	.machine_kexec_prepare	= default_machine_kexec_prepare,
 	.machine_crash_shutdown	= default_machine_crash_shutdown,