1 files changed, 192 insertions, 81 deletions

diff --git a/arch/powerpc/sysdev/xics/xics-common.c b/arch/powerpc/sysdev/xics/xics-common.c
index 9049d9f44485..c3fa539a9898 100644
--- a/arch/powerpc/sysdev/xics/xics-common.c
+++ b/arch/powerpc/sysdev/xics/xics-common.c
@@ -1,16 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright 2011 IBM Corporation.
- *
- *  This program is free software; you can redistribute it and/or
- *  modify it under the terms of the GNU General Public License
- *  as published by the Free Software Foundation; either version
- *  2 of the License, or (at your option) any later version.
- *
  */
 #include <linux/types.h>
 #include <linux/threads.h>
 #include <linux/kernel.h>
 #include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/debugfs.h>
 #include <linux/smp.h>
 #include <linux/interrupt.h>
@@ -20,8 +16,8 @@
 #include <linux/of.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
+#include <linux/delay.h>
 
-#include <asm/prom.h>
 #include <asm/io.h>
 #include <asm/smp.h>
 #include <asm/machdep.h>
@@ -42,14 +38,14 @@ DEFINE_PER_CPU(struct xics_cppr, xics_cppr);
 
 struct irq_domain *xics_host;
 
-static LIST_HEAD(ics_list);
+static struct ics *xics_ics;
 
 void xics_update_irq_servers(void)
 {
 	int i, j;
 	struct device_node *np;
 	u32 ilen;
-	const u32 *ireg;
+	const __be32 *ireg;
 	u32 hcpuid;
 
 	/* Find the server numbers for the boot cpu. */
@@ -75,8 +71,8 @@ void xics_update_irq_servers(void)
 	 * default distribution server
 	 */
 	for (j = 0; j < i; j += 2) {
-		if (ireg[j] == hcpuid) {
-			xics_default_distrib_server = ireg[j+1];
+		if (be32_to_cpu(ireg[j]) == hcpuid) {
+			xics_default_distrib_server = be32_to_cpu(ireg[j+1]);
 			break;
 		}
 	}
@@ -115,47 +111,44 @@ void xics_setup_cpu(void)
 
 void xics_mask_unknown_vec(unsigned int vec)
 {
-	struct ics *ics;
-
 	pr_err("Interrupt 0x%x (real) is invalid, disabling it.\n", vec);
 
-	list_for_each_entry(ics, &ics_list, link)
-		ics->mask_unknown(ics, vec);
+	if (WARN_ON(!xics_ics))
+		return;
+	xics_ics->mask_unknown(xics_ics, vec);
 }
 
 
 #ifdef CONFIG_SMP
 
-static void xics_request_ipi(void)
+static void __init xics_request_ipi(void)
 {
 	unsigned int ipi;
 
 	ipi = irq_create_mapping(xics_host, XICS_IPI);
-	BUG_ON(ipi == NO_IRQ);
+	BUG_ON(!ipi);
 
 	/*
 	 * IPIs are marked IRQF_PERCPU. The handler was set in map.
 	 */
 	BUG_ON(request_irq(ipi, icp_ops->ipi_action,
-			   IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL));
+			   IRQF_NO_DEBUG | IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL));
 }
 
-int __init xics_smp_probe(void)
+void __init xics_smp_probe(void)
 {
-	/* Setup cause_ipi callback  based on which ICP is used */
-	smp_ops->cause_ipi = icp_ops->cause_ipi;
-
 	/* Register all the IPIs */
 	xics_request_ipi();
 
-	return cpumask_weight(cpu_possible_mask);
+	/* Setup cause_ipi callback based on which ICP is used */
+	smp_ops->cause_ipi = icp_ops->cause_ipi;
 }
 
 #endif /* CONFIG_SMP */
 
-void xics_teardown_cpu(void)
+noinstr void xics_teardown_cpu(void)
 {
-	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
+	struct xics_cppr *os_cppr = this_cpu_ptr(&xics_cppr);
 
 	/*
 	 * we have to reset the cppr index to 0 because we're
@@ -166,7 +159,7 @@ void xics_teardown_cpu(void)
 	icp_ops->teardown_cpu();
 }
 
-void xics_kexec_teardown_cpu(int secondary)
+noinstr void xics_kexec_teardown_cpu(int secondary)
 {
 	xics_teardown_cpu();
 
@@ -190,6 +183,8 @@ void xics_migrate_irqs_away(void)
 	unsigned int irq, virq;
 	struct irq_desc *desc;
 
+	pr_debug("%s: CPU %u\n", __func__, cpu);
+
 	/* If we used to be the default server, move to the new "boot_cpuid" */
 	if (hw_cpu == xics_default_server)
 		xics_update_irq_servers();
@@ -200,24 +195,23 @@ void xics_migrate_irqs_away(void)
 	/* Remove ourselves from the global interrupt queue */
 	xics_set_cpu_giq(xics_default_distrib_server, 0);
 
-	/* Allow IPIs again... */
-	icp_ops->set_priority(DEFAULT_PRIORITY);
-
 	for_each_irq_desc(virq, desc) {
 		struct irq_chip *chip;
 		long server;
 		unsigned long flags;
-		struct ics *ics;
+		struct irq_data *irqd;
 
 		/* We can't set affinity on ISA interrupts */
-		if (virq < NUM_ISA_INTERRUPTS)
+		if (virq < NR_IRQS_LEGACY)
 			continue;
 		/* We only need to migrate enabled IRQS */
 		if (!desc->action)
 			continue;
-		if (desc->irq_data.domain != xics_host)
+		/* We need a mapping in the XICS IRQ domain */
+		irqd = irq_domain_get_irq_data(xics_host, virq);
+		if (!irqd)
 			continue;
-		irq = desc->irq_data.hwirq;
+		irq = irqd_to_hwirq(irqd);
 		/* We need to get IPIs still. */
 		if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
 			continue;
@@ -228,13 +222,10 @@ void xics_migrate_irqs_away(void)
 		raw_spin_lock_irqsave(&desc->lock, flags);
 
 		/* Locate interrupt server */
-		server = -1;
-		ics = irq_get_chip_data(virq);
-		if (ics)
-			server = ics->get_server(ics, irq);
+		server = xics_ics->get_server(xics_ics, irq);
 		if (server < 0) {
-			printk(KERN_ERR "%s: Can't find server for irq %d\n",
-			       __func__, irq);
+			pr_err("%s: Can't find server for irq %d/%x\n",
+			       __func__, virq, irq);
 			goto unlock;
 		}
 
@@ -247,8 +238,8 @@ void xics_migrate_irqs_away(void)
 
 		/* This is expected during cpu offline. */
 		if (cpu_online(cpu))
-			pr_warning("IRQ %u affinity broken off cpu %u\n",
-			       virq, cpu);
+			pr_warn("IRQ %u affinity broken off cpu %u\n",
+				virq, cpu);
 
 		/* Reset affinity to all cpus */
 		raw_spin_unlock_irqrestore(&desc->lock, flags);
@@ -257,6 +248,19 @@ void xics_migrate_irqs_away(void)
 unlock:
 		raw_spin_unlock_irqrestore(&desc->lock, flags);
 	}
+
+	/* Allow "sufficient" time to drop any inflight IRQ's */
+	mdelay(5);
+
+	/*
+	 * Allow IPIs again. This is done at the very end, after migrating all
+	 * interrupts, the expectation is that we'll only get woken up by an IPI
+	 * interrupt beyond this point, but leave externals masked just to be
+	 * safe. If we're using icp-opal this may actually allow all
+	 * interrupts anyway, but that should be OK.
+	 */
+	icp_ops->set_priority(DEFAULT_PRIORITY);
+
 }
 #endif /* CONFIG_HOTPLUG_CPU */
 
@@ -300,15 +304,12 @@ int xics_get_irq_server(unsigned int virq, const struct cpumask *cpumask,
 }
 #endif /* CONFIG_SMP */
 
-static int xics_host_match(struct irq_domain *h, struct device_node *node)
+static int xics_host_match(struct irq_domain *h, struct device_node *node,
+			   enum irq_domain_bus_token bus_token)
 {
-	struct ics *ics;
-
-	list_for_each_entry(ics, &ics_list, link)
-		if (ics->host_match(ics, node))
-			return 1;
-
-	return 0;
+	if (WARN_ON(!xics_ics))
+		return 0;
+	return xics_ics->host_match(xics_ics, node) ? 1 : 0;
 }
 
 /* Dummies */
@@ -322,29 +323,36 @@ static struct irq_chip xics_ipi_chip = {
 	.irq_unmask = xics_ipi_unmask,
 };
 
-static int xics_host_map(struct irq_domain *h, unsigned int virq,
-			 irq_hw_number_t hw)
+static int xics_host_map(struct irq_domain *domain, unsigned int virq,
+			 irq_hw_number_t hwirq)
 {
-	struct ics *ics;
-
-	pr_devel("xics: map virq %d, hwirq 0x%lx\n", virq, hw);
+	pr_devel("xics: map virq %d, hwirq 0x%lx\n", virq, hwirq);
 
-	/* They aren't all level sensitive but we just don't really know */
-	irq_set_status_flags(virq, IRQ_LEVEL);
+	/*
+	 * Mark interrupts as edge sensitive by default so that resend
+	 * actually works. The device-tree parsing will turn the LSIs
+	 * back to level.
+	 */
+	irq_clear_status_flags(virq, IRQ_LEVEL);
 
 	/* Don't call into ICS for IPIs */
-	if (hw == XICS_IPI) {
+	if (hwirq == XICS_IPI) {
 		irq_set_chip_and_handler(virq, &xics_ipi_chip,
 					 handle_percpu_irq);
 		return 0;
 	}
 
-	/* Let the ICS setup the chip data */
-	list_for_each_entry(ics, &ics_list, link)
-		if (ics->map(ics, virq) == 0)
-			return 0;
+	if (WARN_ON(!xics_ics))
+		return -EINVAL;
+
+	if (xics_ics->check(xics_ics, hwirq))
+		return -EINVAL;
 
-	return -EINVAL;
+	/* Let the ICS be the chip data for the XICS domain. For ICS native */
+	irq_domain_set_info(domain, virq, hwirq, xics_ics->chip,
+			    xics_ics, handle_fasteoi_irq, NULL, NULL);
+
+	return 0;
 }
 
 static int xics_host_xlate(struct irq_domain *h, struct device_node *ct,
@@ -352,38 +360,133 @@ static int xics_host_xlate(struct irq_domain *h, struct device_node *ct,
 			   irq_hw_number_t *out_hwirq, unsigned int *out_flags)
 
 {
-	/* Current xics implementation translates everything
-	 * to level. It is not technically right for MSIs but this
-	 * is irrelevant at this point. We might get smarter in the future
-	 */
 	*out_hwirq = intspec[0];
-	*out_flags = IRQ_TYPE_LEVEL_LOW;
+
+	/*
+	 * If intsize is at least 2, we look for the type in the second cell,
+	 * we assume the LSB indicates a level interrupt.
+	 */
+	if (intsize > 1) {
+		if (intspec[1] & 1)
+			*out_flags = IRQ_TYPE_LEVEL_LOW;
+		else
+			*out_flags = IRQ_TYPE_EDGE_RISING;
+	} else
+		*out_flags = IRQ_TYPE_LEVEL_LOW;
 
 	return 0;
 }
 
-static struct irq_domain_ops xics_host_ops = {
+int xics_set_irq_type(struct irq_data *d, unsigned int flow_type)
+{
+	/*
+	 * We only support these. This has really no effect other than setting
+	 * the corresponding descriptor bits mind you but those will in turn
+	 * affect the resend function when re-enabling an edge interrupt.
+	 *
+	 * Set set the default to edge as explained in map().
+	 */
+	if (flow_type == IRQ_TYPE_DEFAULT || flow_type == IRQ_TYPE_NONE)
+		flow_type = IRQ_TYPE_EDGE_RISING;
+
+	if (flow_type != IRQ_TYPE_EDGE_RISING &&
+	    flow_type != IRQ_TYPE_LEVEL_LOW)
+		return -EINVAL;
+
+	irqd_set_trigger_type(d, flow_type);
+
+	return IRQ_SET_MASK_OK_NOCOPY;
+}
+
+int xics_retrigger(struct irq_data *data)
+{
+	/*
+	 * We need to push a dummy CPPR when retriggering, since the subsequent
+	 * EOI will try to pop it. Passing 0 works, as the function hard codes
+	 * the priority value anyway.
+	 */
+	xics_push_cppr(0);
+
+	/* Tell the core to do a soft retrigger */
+	return 0;
+}
+
+#ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
+static int xics_host_domain_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
+				      unsigned long *hwirq, unsigned int *type)
+{
+	return xics_host_xlate(d, to_of_node(fwspec->fwnode), fwspec->param,
+			       fwspec->param_count, hwirq, type);
+}
+
+static int xics_host_domain_alloc(struct irq_domain *domain, unsigned int virq,
+				  unsigned int nr_irqs, void *arg)
+{
+	struct irq_fwspec *fwspec = arg;
+	irq_hw_number_t hwirq;
+	unsigned int type = IRQ_TYPE_NONE;
+	int i, rc;
+
+	rc = xics_host_domain_translate(domain, fwspec, &hwirq, &type);
+	if (rc)
+		return rc;
+
+	pr_debug("%s %d/%lx #%d\n", __func__, virq, hwirq, nr_irqs);
+
+	for (i = 0; i < nr_irqs; i++)
+		irq_domain_set_info(domain, virq + i, hwirq + i, xics_ics->chip,
+				    xics_ics, handle_fasteoi_irq, NULL, NULL);
+
+	return 0;
+}
+
+static void xics_host_domain_free(struct irq_domain *domain,
+				  unsigned int virq, unsigned int nr_irqs)
+{
+	pr_debug("%s %d #%d\n", __func__, virq, nr_irqs);
+}
+#endif
+
+static const struct irq_domain_ops xics_host_ops = {
+#ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
+	.alloc	= xics_host_domain_alloc,
+	.free	= xics_host_domain_free,
+	.translate = xics_host_domain_translate,
+#endif
 	.match = xics_host_match,
 	.map = xics_host_map,
 	.xlate = xics_host_xlate,
 };
 
-static void __init xics_init_host(void)
+static int __init xics_allocate_domain(void)
 {
-	xics_host = irq_domain_add_tree(NULL, &xics_host_ops, NULL);
-	BUG_ON(xics_host == NULL);
-	irq_set_default_host(xics_host);
+	struct fwnode_handle *fn;
+
+	fn = irq_domain_alloc_named_fwnode("XICS");
+	if (!fn)
+		return -ENOMEM;
+
+	xics_host = irq_domain_create_tree(fn, &xics_host_ops, NULL);
+	if (!xics_host) {
+		irq_domain_free_fwnode(fn);
+		return -ENOMEM;
+	}
+
+	irq_set_default_domain(xics_host);
+	return 0;
 }
 
 void __init xics_register_ics(struct ics *ics)
 {
-	list_add(&ics->link, &ics_list);
+	if (WARN_ONCE(xics_ics, "XICS: Source Controller is already defined !"))
+		return;
+	xics_ics = ics;
 }
 
 static void __init xics_get_server_size(void)
 {
 	struct device_node *np;
-	const u32 *isize;
+	const __be32 *isize;
 
 	/* We fetch the interrupt server size from the first ICS node
 	 * we find if any
@@ -391,10 +494,11 @@ static void __init xics_get_server_size(void)
 	np = of_find_compatible_node(NULL, NULL, "ibm,ppc-xics");
 	if (!np)
 		return;
+
 	isize = of_get_property(np, "ibm,interrupt-server#-size", NULL);
-	if (!isize)
-		return;
-	xics_interrupt_server_size = *isize;
+	if (isize)
+		xics_interrupt_server_size = be32_to_cpu(*isize);
+
 	of_node_put(np);
 }
 
@@ -405,10 +509,13 @@ void __init xics_init(void)
 	/* Fist locate ICP */
 	if (firmware_has_feature(FW_FEATURE_LPAR))
 		rc = icp_hv_init();
-	if (rc < 0)
+	if (rc < 0) {
 		rc = icp_native_init();
+		if (rc == -ENODEV)
+		    rc = icp_opal_init();
+	}
 	if (rc < 0) {
-		pr_warning("XICS: Cannot find a Presentation Controller !\n");
+		pr_warn("XICS: Cannot find a Presentation Controller !\n");
 		return;
 	}
 
@@ -423,11 +530,15 @@ void __init xics_init(void)
 	if (rc < 0)
 		rc = ics_opal_init();
 	if (rc < 0)
-		pr_warning("XICS: Cannot find a Source Controller !\n");
+		rc = ics_native_init();
+	if (rc < 0)
+		pr_warn("XICS: Cannot find a Source Controller !\n");
 
 	/* Initialize common bits */
 	xics_get_server_size();
 	xics_update_irq_servers();
-	xics_init_host();
+	rc = xics_allocate_domain();
+	if (rc < 0)
+		pr_err("XICS: Failed to create IRQ domain");
 	xics_setup_cpu();
 }