1 files changed, 488 insertions, 0 deletions

diff --git a/arch/ia64/sn/kernel/irq.c b/arch/ia64/sn/kernel/irq.c
new file mode 100644
index 000000000..85d095154
--- /dev/null
+++ b/arch/ia64/sn/kernel/irq.c
@@ -0,0 +1,488 @@
+/*
+ * Platform dependent support for SGI SN
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2000-2008 Silicon Graphics, Inc.  All Rights Reserved.
+ */
+
+#include <linux/irq.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/rculist.h>
+#include <linux/slab.h>
+#include <asm/sn/addrs.h>
+#include <asm/sn/arch.h>
+#include <asm/sn/intr.h>
+#include <asm/sn/pcibr_provider.h>
+#include <asm/sn/pcibus_provider_defs.h>
+#include <asm/sn/pcidev.h>
+#include <asm/sn/shub_mmr.h>
+#include <asm/sn/sn_sal.h>
+#include <asm/sn/sn_feature_sets.h>
+
+static void register_intr_pda(struct sn_irq_info *sn_irq_info);
+static void unregister_intr_pda(struct sn_irq_info *sn_irq_info);
+
+extern int sn_ioif_inited;
+struct list_head **sn_irq_lh;
+static DEFINE_SPINLOCK(sn_irq_info_lock); /* non-IRQ lock */
+
+u64 sn_intr_alloc(nasid_t local_nasid, int local_widget,
+				     struct sn_irq_info *sn_irq_info,
+				     int req_irq, nasid_t req_nasid,
+				     int req_slice)
+{
+	struct ia64_sal_retval ret_stuff;
+	ret_stuff.status = 0;
+	ret_stuff.v0 = 0;
+
+	SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
+			(u64) SAL_INTR_ALLOC, (u64) local_nasid,
+			(u64) local_widget, __pa(sn_irq_info), (u64) req_irq,
+			(u64) req_nasid, (u64) req_slice);
+
+	return ret_stuff.status;
+}
+
+void sn_intr_free(nasid_t local_nasid, int local_widget,
+				struct sn_irq_info *sn_irq_info)
+{
+	struct ia64_sal_retval ret_stuff;
+	ret_stuff.status = 0;
+	ret_stuff.v0 = 0;
+
+	SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
+			(u64) SAL_INTR_FREE, (u64) local_nasid,
+			(u64) local_widget, (u64) sn_irq_info->irq_irq,
+			(u64) sn_irq_info->irq_cookie, 0, 0);
+}
+
+u64 sn_intr_redirect(nasid_t local_nasid, int local_widget,
+		      struct sn_irq_info *sn_irq_info,
+		      nasid_t req_nasid, int req_slice)
+{
+	struct ia64_sal_retval ret_stuff;
+	ret_stuff.status = 0;
+	ret_stuff.v0 = 0;
+
+	SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
+			(u64) SAL_INTR_REDIRECT, (u64) local_nasid,
+			(u64) local_widget, __pa(sn_irq_info),
+			(u64) req_nasid, (u64) req_slice, 0);
+
+	return ret_stuff.status;
+}
+
+static unsigned int sn_startup_irq(struct irq_data *data)
+{
+	return 0;
+}
+
+static void sn_shutdown_irq(struct irq_data *data)
+{
+}
+
+extern void ia64_mca_register_cpev(int);
+
+static void sn_disable_irq(struct irq_data *data)
+{
+	if (data->irq == local_vector_to_irq(IA64_CPE_VECTOR))
+		ia64_mca_register_cpev(0);
+}
+
+static void sn_enable_irq(struct irq_data *data)
+{
+	if (data->irq == local_vector_to_irq(IA64_CPE_VECTOR))
+		ia64_mca_register_cpev(data->irq);
+}
+
+static void sn_ack_irq(struct irq_data *data)
+{
+	u64 event_occurred, mask;
+	unsigned int irq = data->irq & 0xff;
+
+	event_occurred = HUB_L((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED));
+	mask = event_occurred & SH_ALL_INT_MASK;
+	HUB_S((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS), mask);
+	__set_bit(irq, (volatile void *)pda->sn_in_service_ivecs);
+
+	irq_move_irq(data);
+}
+
+struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info,
+				       nasid_t nasid, int slice)
+{
+	int vector;
+	int cpuid;
+#ifdef CONFIG_SMP
+	int cpuphys;
+#endif
+	int64_t bridge;
+	int local_widget, status;
+	nasid_t local_nasid;
+	struct sn_irq_info *new_irq_info;
+	struct sn_pcibus_provider *pci_provider;
+
+	bridge = (u64) sn_irq_info->irq_bridge;
+	if (!bridge) {
+		return NULL; /* irq is not a device interrupt */
+	}
+
+	local_nasid = NASID_GET(bridge);
+
+	if (local_nasid & 1)
+		local_widget = TIO_SWIN_WIDGETNUM(bridge);
+	else
+		local_widget = SWIN_WIDGETNUM(bridge);
+	vector = sn_irq_info->irq_irq;
+
+	/* Make use of SAL_INTR_REDIRECT if PROM supports it */
+	status = sn_intr_redirect(local_nasid, local_widget, sn_irq_info, nasid, slice);
+	if (!status) {
+		new_irq_info = sn_irq_info;
+		goto finish_up;
+	}
+
+	/*
+	 * PROM does not support SAL_INTR_REDIRECT, or it failed.
+	 * Revert to old method.
+	 */
+	new_irq_info = kmemdup(sn_irq_info, sizeof(struct sn_irq_info),
+			       GFP_ATOMIC);
+	if (new_irq_info == NULL)
+		return NULL;
+
+	/* Free the old PROM new_irq_info structure */
+	sn_intr_free(local_nasid, local_widget, new_irq_info);
+	unregister_intr_pda(new_irq_info);
+
+	/* allocate a new PROM new_irq_info struct */
+	status = sn_intr_alloc(local_nasid, local_widget,
+			       new_irq_info, vector,
+			       nasid, slice);
+
+	/* SAL call failed */
+	if (status) {
+		kfree(new_irq_info);
+		return NULL;
+	}
+
+	register_intr_pda(new_irq_info);
+	spin_lock(&sn_irq_info_lock);
+	list_replace_rcu(&sn_irq_info->list, &new_irq_info->list);
+	spin_unlock(&sn_irq_info_lock);
+	kfree_rcu(sn_irq_info, rcu);
+
+
+finish_up:
+	/* Update kernels new_irq_info with new target info */
+	cpuid = nasid_slice_to_cpuid(new_irq_info->irq_nasid,
+				     new_irq_info->irq_slice);
+	new_irq_info->irq_cpuid = cpuid;
+
+	pci_provider = sn_pci_provider[new_irq_info->irq_bridge_type];
+
+	/*
+	 * If this represents a line interrupt, target it.  If it's
+	 * an msi (irq_int_bit < 0), it's already targeted.
+	 */
+	if (new_irq_info->irq_int_bit >= 0 &&
+	    pci_provider && pci_provider->target_interrupt)
+		(pci_provider->target_interrupt)(new_irq_info);
+
+#ifdef CONFIG_SMP
+	cpuphys = cpu_physical_id(cpuid);
+	set_irq_affinity_info((vector & 0xff), cpuphys, 0);
+#endif
+
+	return new_irq_info;
+}
+
+static int sn_set_affinity_irq(struct irq_data *data,
+			       const struct cpumask *mask, bool force)
+{
+	struct sn_irq_info *sn_irq_info, *sn_irq_info_safe;
+	unsigned int irq = data->irq;
+	nasid_t nasid;
+	int slice;
+
+	nasid = cpuid_to_nasid(cpumask_first_and(mask, cpu_online_mask));
+	slice = cpuid_to_slice(cpumask_first_and(mask, cpu_online_mask));
+
+	list_for_each_entry_safe(sn_irq_info, sn_irq_info_safe,
+				 sn_irq_lh[irq], list)
+		(void)sn_retarget_vector(sn_irq_info, nasid, slice);
+
+	return 0;
+}
+
+#ifdef CONFIG_SMP
+void sn_set_err_irq_affinity(unsigned int irq)
+{
+        /*
+         * On systems which support CPU disabling (SHub2), all error interrupts
+         * are targeted at the boot CPU.
+         */
+        if (is_shub2() && sn_prom_feature_available(PRF_CPU_DISABLE_SUPPORT))
+                set_irq_affinity_info(irq, cpu_physical_id(0), 0);
+}
+#else
+void sn_set_err_irq_affinity(unsigned int irq) { }
+#endif
+
+static void
+sn_mask_irq(struct irq_data *data)
+{
+}
+
+static void
+sn_unmask_irq(struct irq_data *data)
+{
+}
+
+struct irq_chip irq_type_sn = {
+	.name			= "SN hub",
+	.irq_startup		= sn_startup_irq,
+	.irq_shutdown		= sn_shutdown_irq,
+	.irq_enable		= sn_enable_irq,
+	.irq_disable		= sn_disable_irq,
+	.irq_ack		= sn_ack_irq,
+	.irq_mask		= sn_mask_irq,
+	.irq_unmask		= sn_unmask_irq,
+	.irq_set_affinity	= sn_set_affinity_irq
+};
+
+ia64_vector sn_irq_to_vector(int irq)
+{
+	if (irq >= IA64_NUM_VECTORS)
+		return 0;
+	return (ia64_vector)irq;
+}
+
+unsigned int sn_local_vector_to_irq(u8 vector)
+{
+	return (CPU_VECTOR_TO_IRQ(smp_processor_id(), vector));
+}
+
+void sn_irq_init(void)
+{
+	int i;
+
+	ia64_first_device_vector = IA64_SN2_FIRST_DEVICE_VECTOR;
+	ia64_last_device_vector = IA64_SN2_LAST_DEVICE_VECTOR;
+
+	for (i = 0; i < NR_IRQS; i++) {
+		if (irq_get_chip(i) == &no_irq_chip)
+			irq_set_chip(i, &irq_type_sn);
+	}
+}
+
+static void register_intr_pda(struct sn_irq_info *sn_irq_info)
+{
+	int irq = sn_irq_info->irq_irq;
+	int cpu = sn_irq_info->irq_cpuid;
+
+	if (pdacpu(cpu)->sn_last_irq < irq) {
+		pdacpu(cpu)->sn_last_irq = irq;
+	}
+
+	if (pdacpu(cpu)->sn_first_irq == 0 || pdacpu(cpu)->sn_first_irq > irq)
+		pdacpu(cpu)->sn_first_irq = irq;
+}
+
+static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
+{
+	int irq = sn_irq_info->irq_irq;
+	int cpu = sn_irq_info->irq_cpuid;
+	struct sn_irq_info *tmp_irq_info;
+	int i, foundmatch;
+
+	rcu_read_lock();
+	if (pdacpu(cpu)->sn_last_irq == irq) {
+		foundmatch = 0;
+		for (i = pdacpu(cpu)->sn_last_irq - 1;
+		     i && !foundmatch; i--) {
+			list_for_each_entry_rcu(tmp_irq_info,
+						sn_irq_lh[i],
+						list) {
+				if (tmp_irq_info->irq_cpuid == cpu) {
+					foundmatch = 1;
+					break;
+				}
+			}
+		}
+		pdacpu(cpu)->sn_last_irq = i;
+	}
+
+	if (pdacpu(cpu)->sn_first_irq == irq) {
+		foundmatch = 0;
+		for (i = pdacpu(cpu)->sn_first_irq + 1;
+		     i < NR_IRQS && !foundmatch; i++) {
+			list_for_each_entry_rcu(tmp_irq_info,
+						sn_irq_lh[i],
+						list) {
+				if (tmp_irq_info->irq_cpuid == cpu) {
+					foundmatch = 1;
+					break;
+				}
+			}
+		}
+		pdacpu(cpu)->sn_first_irq = ((i == NR_IRQS) ? 0 : i);
+	}
+	rcu_read_unlock();
+}
+
+void sn_irq_fixup(struct pci_dev *pci_dev, struct sn_irq_info *sn_irq_info)
+{
+	nasid_t nasid = sn_irq_info->irq_nasid;
+	int slice = sn_irq_info->irq_slice;
+	int cpu = nasid_slice_to_cpuid(nasid, slice);
+#ifdef CONFIG_SMP
+	int cpuphys;
+#endif
+
+	pci_dev_get(pci_dev);
+	sn_irq_info->irq_cpuid = cpu;
+	sn_irq_info->irq_pciioinfo = SN_PCIDEV_INFO(pci_dev);
+
+	/* link it into the sn_irq[irq] list */
+	spin_lock(&sn_irq_info_lock);
+	list_add_rcu(&sn_irq_info->list, sn_irq_lh[sn_irq_info->irq_irq]);
+	reserve_irq_vector(sn_irq_info->irq_irq);
+	if (sn_irq_info->irq_int_bit != -1)
+		irq_set_handler(sn_irq_info->irq_irq, handle_level_irq);
+	spin_unlock(&sn_irq_info_lock);
+
+	register_intr_pda(sn_irq_info);
+#ifdef CONFIG_SMP
+	cpuphys = cpu_physical_id(cpu);
+	set_irq_affinity_info(sn_irq_info->irq_irq, cpuphys, 0);
+	/*
+	 * Affinity was set by the PROM, prevent it from
+	 * being reset by the request_irq() path.
+	 */
+	irqd_mark_affinity_was_set(irq_get_irq_data(sn_irq_info->irq_irq));
+#endif
+}
+
+void sn_irq_unfixup(struct pci_dev *pci_dev)
+{
+	struct sn_irq_info *sn_irq_info;
+
+	/* Only cleanup IRQ stuff if this device has a host bus context */
+	if (!SN_PCIDEV_BUSSOFT(pci_dev))
+		return;
+
+	sn_irq_info = SN_PCIDEV_INFO(pci_dev)->pdi_sn_irq_info;
+	if (!sn_irq_info)
+		return;
+	if (!sn_irq_info->irq_irq) {
+		kfree(sn_irq_info);
+		return;
+	}
+
+	unregister_intr_pda(sn_irq_info);
+	spin_lock(&sn_irq_info_lock);
+	list_del_rcu(&sn_irq_info->list);
+	spin_unlock(&sn_irq_info_lock);
+	if (list_empty(sn_irq_lh[sn_irq_info->irq_irq]))
+		free_irq_vector(sn_irq_info->irq_irq);
+	kfree_rcu(sn_irq_info, rcu);
+	pci_dev_put(pci_dev);
+
+}
+
+static inline void
+sn_call_force_intr_provider(struct sn_irq_info *sn_irq_info)
+{
+	struct sn_pcibus_provider *pci_provider;
+
+	pci_provider = sn_pci_provider[sn_irq_info->irq_bridge_type];
+
+	/* Don't force an interrupt if the irq has been disabled */
+	if (!irqd_irq_disabled(irq_get_irq_data(sn_irq_info->irq_irq)) &&
+	    pci_provider && pci_provider->force_interrupt)
+		(*pci_provider->force_interrupt)(sn_irq_info);
+}
+
+/*
+ * Check for lost interrupts.  If the PIC int_status reg. says that
+ * an interrupt has been sent, but not handled, and the interrupt
+ * is not pending in either the cpu irr regs or in the soft irr regs,
+ * and the interrupt is not in service, then the interrupt may have
+ * been lost.  Force an interrupt on that pin.  It is possible that
+ * the interrupt is in flight, so we may generate a spurious interrupt,
+ * but we should never miss a real lost interrupt.
+ */
+static void sn_check_intr(int irq, struct sn_irq_info *sn_irq_info)
+{
+	u64 regval;
+	struct pcidev_info *pcidev_info;
+	struct pcibus_info *pcibus_info;
+
+	/*
+	 * Bridge types attached to TIO (anything but PIC) do not need this WAR
+	 * since they do not target Shub II interrupt registers.  If that
+	 * ever changes, this check needs to accommodate.
+	 */
+	if (sn_irq_info->irq_bridge_type != PCIIO_ASIC_TYPE_PIC)
+		return;
+
+	pcidev_info = (struct pcidev_info *)sn_irq_info->irq_pciioinfo;
+	if (!pcidev_info)
+		return;
+
+	pcibus_info =
+	    (struct pcibus_info *)pcidev_info->pdi_host_pcidev_info->
+	    pdi_pcibus_info;
+	regval = pcireg_intr_status_get(pcibus_info);
+
+	if (!ia64_get_irr(irq_to_vector(irq))) {
+		if (!test_bit(irq, pda->sn_in_service_ivecs)) {
+			regval &= 0xff;
+			if (sn_irq_info->irq_int_bit & regval &
+			    sn_irq_info->irq_last_intr) {
+				regval &= ~(sn_irq_info->irq_int_bit & regval);
+				sn_call_force_intr_provider(sn_irq_info);
+			}
+		}
+	}
+	sn_irq_info->irq_last_intr = regval;
+}
+
+void sn_lb_int_war_check(void)
+{
+	struct sn_irq_info *sn_irq_info;
+	int i;
+
+	if (!sn_ioif_inited || pda->sn_first_irq == 0)
+		return;
+
+	rcu_read_lock();
+	for (i = pda->sn_first_irq; i <= pda->sn_last_irq; i++) {
+		list_for_each_entry_rcu(sn_irq_info, sn_irq_lh[i], list) {
+			sn_check_intr(i, sn_irq_info);
+		}
+	}
+	rcu_read_unlock();
+}
+
+void __init sn_irq_lh_init(void)
+{
+	int i;
+
+	sn_irq_lh = kmalloc(sizeof(struct list_head *) * NR_IRQS, GFP_KERNEL);
+	if (!sn_irq_lh)
+		panic("SN PCI INIT: Failed to allocate memory for PCI init\n");
+
+	for (i = 0; i < NR_IRQS; i++) {
+		sn_irq_lh[i] = kmalloc(sizeof(struct list_head), GFP_KERNEL);
+		if (!sn_irq_lh[i])
+			panic("SN PCI INIT: Failed IRQ memory allocation\n");
+
+		INIT_LIST_HEAD(sn_irq_lh[i]);
+	}
+}