--- /dev/null
+/*
+ * Cell Internal Interrupt Controller
+ *
+ * Copyright (C) 2006 Benjamin Herrenschmidt (benh@kernel.crashing.org)
+ * IBM, Corp.
+ *
+ * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
+ *
+ * Author: Arnd Bergmann <arndb@de.ibm.com>
+ *
+ * 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, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * TODO:
+ * - Fix various assumptions related to HW CPU numbers vs. linux CPU numbers
+ * vs node numbers in the setup code
+ * - Implement proper handling of maxcpus=1/2 (that is, routing of irqs from
+ * a non-active node to the active node)
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/export.h>
+#include <linux/percpu.h>
+#include <linux/types.h>
+#include <linux/ioport.h>
+#include <linux/kernel_stat.h>
+
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/prom.h>
+#include <asm/ptrace.h>
+#include <asm/machdep.h>
+#include <asm/cell-regs.h>
+
+#include "interrupt.h"
+
+struct iic {
+ struct cbe_iic_thread_regs __iomem *regs;
+ u8 target_id;
+ u8 eoi_stack[16];
+ int eoi_ptr;
+ struct device_node *node;
+};
+
+static DEFINE_PER_CPU(struct iic, cpu_iic);
+#define IIC_NODE_COUNT 2
+static struct irq_domain *iic_host;
+
+/* Convert between "pending" bits and hw irq number */
+static irq_hw_number_t iic_pending_to_hwnum(struct cbe_iic_pending_bits bits)
+{
+ unsigned char unit = bits.source & 0xf;
+ unsigned char node = bits.source >> 4;
+ unsigned char class = bits.class & 3;
+
+ /* Decode IPIs */
+ if (bits.flags & CBE_IIC_IRQ_IPI)
+ return IIC_IRQ_TYPE_IPI | (bits.prio >> 4);
+ else
+ return (node << IIC_IRQ_NODE_SHIFT) | (class << 4) | unit;
+}
+
+static void iic_mask(struct irq_data *d)
+{
+}
+
+static void iic_unmask(struct irq_data *d)
+{
+}
+
+static void iic_eoi(struct irq_data *d)
+{
+ struct iic *iic = this_cpu_ptr(&cpu_iic);
+ out_be64(&iic->regs->prio, iic->eoi_stack[--iic->eoi_ptr]);
+ BUG_ON(iic->eoi_ptr < 0);
+}
+
+static struct irq_chip iic_chip = {
+ .name = "CELL-IIC",
+ .irq_mask = iic_mask,
+ .irq_unmask = iic_unmask,
+ .irq_eoi = iic_eoi,
+};
+
+
+static void iic_ioexc_eoi(struct irq_data *d)
+{
+}
+
+static void iic_ioexc_cascade(unsigned int irq, struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct cbe_iic_regs __iomem *node_iic =
+ (void __iomem *)irq_desc_get_handler_data(desc);
+ unsigned int base = (irq & 0xffffff00) | IIC_IRQ_TYPE_IOEXC;
+ unsigned long bits, ack;
+ int cascade;
+
+ for (;;) {
+ bits = in_be64(&node_iic->iic_is);
+ if (bits == 0)
+ break;
+ /* pre-ack edge interrupts */
+ ack = bits & IIC_ISR_EDGE_MASK;
+ if (ack)
+ out_be64(&node_iic->iic_is, ack);
+ /* handle them */
+ for (cascade = 63; cascade >= 0; cascade--)
+ if (bits & (0x8000000000000000UL >> cascade)) {
+ unsigned int cirq =
+ irq_linear_revmap(iic_host,
+ base | cascade);
+ if (cirq != NO_IRQ)
+ generic_handle_irq(cirq);
+ }
+ /* post-ack level interrupts */
+ ack = bits & ~IIC_ISR_EDGE_MASK;
+ if (ack)
+ out_be64(&node_iic->iic_is, ack);
+ }
+ chip->irq_eoi(&desc->irq_data);
+}
+
+
+static struct irq_chip iic_ioexc_chip = {
+ .name = "CELL-IOEX",
+ .irq_mask = iic_mask,
+ .irq_unmask = iic_unmask,
+ .irq_eoi = iic_ioexc_eoi,
+};
+
+/* Get an IRQ number from the pending state register of the IIC */
+static unsigned int iic_get_irq(void)
+{
+ struct cbe_iic_pending_bits pending;
+ struct iic *iic;
+ unsigned int virq;
+
+ iic = this_cpu_ptr(&cpu_iic);
+ *(unsigned long *) &pending =
+ in_be64((u64 __iomem *) &iic->regs->pending_destr);
+ if (!(pending.flags & CBE_IIC_IRQ_VALID))
+ return NO_IRQ;
+ virq = irq_linear_revmap(iic_host, iic_pending_to_hwnum(pending));
+ if (virq == NO_IRQ)
+ return NO_IRQ;
+ iic->eoi_stack[++iic->eoi_ptr] = pending.prio;
+ BUG_ON(iic->eoi_ptr > 15);
+ return virq;
+}
+
+void iic_setup_cpu(void)
+{
+ out_be64(&this_cpu_ptr(&cpu_iic)->regs->prio, 0xff);
+}
+
+u8 iic_get_target_id(int cpu)
+{
+ return per_cpu(cpu_iic, cpu).target_id;
+}
+
+EXPORT_SYMBOL_GPL(iic_get_target_id);
+
+#ifdef CONFIG_SMP
+
+/* Use the highest interrupt priorities for IPI */
+static inline int iic_msg_to_irq(int msg)
+{
+ return IIC_IRQ_TYPE_IPI + 0xf - msg;
+}
+
+void iic_message_pass(int cpu, int msg)
+{
+ out_be64(&per_cpu(cpu_iic, cpu).regs->generate, (0xf - msg) << 4);
+}
+
+struct irq_domain *iic_get_irq_host(int node)
+{
+ return iic_host;
+}
+EXPORT_SYMBOL_GPL(iic_get_irq_host);
+
+static void iic_request_ipi(int msg)
+{
+ int virq;
+
+ virq = irq_create_mapping(iic_host, iic_msg_to_irq(msg));
+ if (virq == NO_IRQ) {
+ printk(KERN_ERR
+ "iic: failed to map IPI %s\n", smp_ipi_name[msg]);
+ return;
+ }
+
+ /*
+ * If smp_request_message_ipi encounters an error it will notify
+ * the error. If a message is not needed it will return non-zero.
+ */
+ if (smp_request_message_ipi(virq, msg))
+ irq_dispose_mapping(virq);
+}
+
+void iic_request_IPIs(void)
+{
+ iic_request_ipi(PPC_MSG_CALL_FUNCTION);
+ iic_request_ipi(PPC_MSG_RESCHEDULE);
+ iic_request_ipi(PPC_MSG_TICK_BROADCAST);
+ iic_request_ipi(PPC_MSG_DEBUGGER_BREAK);
+}
+
+#endif /* CONFIG_SMP */
+
+
+static int iic_host_match(struct irq_domain *h, struct device_node *node)
+{
+ return of_device_is_compatible(node,
+ "IBM,CBEA-Internal-Interrupt-Controller");
+}
+
+static int iic_host_map(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ switch (hw & IIC_IRQ_TYPE_MASK) {
+ case IIC_IRQ_TYPE_IPI:
+ irq_set_chip_and_handler(virq, &iic_chip, handle_percpu_irq);
+ break;
+ case IIC_IRQ_TYPE_IOEXC:
+ irq_set_chip_and_handler(virq, &iic_ioexc_chip,
+ handle_edge_eoi_irq);
+ break;
+ default:
+ irq_set_chip_and_handler(virq, &iic_chip, handle_edge_eoi_irq);
+ }
+ return 0;
+}
+
+static int iic_host_xlate(struct irq_domain *h, struct device_node *ct,
+ const u32 *intspec, unsigned int intsize,
+ irq_hw_number_t *out_hwirq, unsigned int *out_flags)
+
+{
+ unsigned int node, ext, unit, class;
+ const u32 *val;
+
+ if (!of_device_is_compatible(ct,
+ "IBM,CBEA-Internal-Interrupt-Controller"))
+ return -ENODEV;
+ if (intsize != 1)
+ return -ENODEV;
+ val = of_get_property(ct, "#interrupt-cells", NULL);
+ if (val == NULL || *val != 1)
+ return -ENODEV;
+
+ node = intspec[0] >> 24;
+ ext = (intspec[0] >> 16) & 0xff;
+ class = (intspec[0] >> 8) & 0xff;
+ unit = intspec[0] & 0xff;
+
+ /* Check if node is in supported range */
+ if (node > 1)
+ return -EINVAL;
+
+ /* Build up interrupt number, special case for IO exceptions */
+ *out_hwirq = (node << IIC_IRQ_NODE_SHIFT);
+ if (unit == IIC_UNIT_IIC && class == 1)
+ *out_hwirq |= IIC_IRQ_TYPE_IOEXC | ext;
+ else
+ *out_hwirq |= IIC_IRQ_TYPE_NORMAL |
+ (class << IIC_IRQ_CLASS_SHIFT) | unit;
+
+ /* Dummy flags, ignored by iic code */
+ *out_flags = IRQ_TYPE_EDGE_RISING;
+
+ return 0;
+}
+
+static const struct irq_domain_ops iic_host_ops = {
+ .match = iic_host_match,
+ .map = iic_host_map,
+ .xlate = iic_host_xlate,
+};
+
+static void __init init_one_iic(unsigned int hw_cpu, unsigned long addr,
+ struct device_node *node)
+{
+ /* XXX FIXME: should locate the linux CPU number from the HW cpu
+ * number properly. We are lucky for now
+ */
+ struct iic *iic = &per_cpu(cpu_iic, hw_cpu);
+
+ iic->regs = ioremap(addr, sizeof(struct cbe_iic_thread_regs));
+ BUG_ON(iic->regs == NULL);
+
+ iic->target_id = ((hw_cpu & 2) << 3) | ((hw_cpu & 1) ? 0xf : 0xe);
+ iic->eoi_stack[0] = 0xff;
+ iic->node = of_node_get(node);
+ out_be64(&iic->regs->prio, 0);
+
+ printk(KERN_INFO "IIC for CPU %d target id 0x%x : %s\n",
+ hw_cpu, iic->target_id, node->full_name);
+}
+
+static int __init setup_iic(void)
+{
+ struct device_node *dn;
+ struct resource r0, r1;
+ unsigned int node, cascade, found = 0;
+ struct cbe_iic_regs __iomem *node_iic;
+ const u32 *np;
+
+ for (dn = NULL;
+ (dn = of_find_node_by_name(dn,"interrupt-controller")) != NULL;) {
+ if (!of_device_is_compatible(dn,
+ "IBM,CBEA-Internal-Interrupt-Controller"))
+ continue;
+ np = of_get_property(dn, "ibm,interrupt-server-ranges", NULL);
+ if (np == NULL) {
+ printk(KERN_WARNING "IIC: CPU association not found\n");
+ of_node_put(dn);
+ return -ENODEV;
+ }
+ if (of_address_to_resource(dn, 0, &r0) ||
+ of_address_to_resource(dn, 1, &r1)) {
+ printk(KERN_WARNING "IIC: Can't resolve addresses\n");
+ of_node_put(dn);
+ return -ENODEV;
+ }
+ found++;
+ init_one_iic(np[0], r0.start, dn);
+ init_one_iic(np[1], r1.start, dn);
+
+ /* Setup cascade for IO exceptions. XXX cleanup tricks to get
+ * node vs CPU etc...
+ * Note that we configure the IIC_IRR here with a hard coded
+ * priority of 1. We might want to improve that later.
+ */
+ node = np[0] >> 1;
+ node_iic = cbe_get_cpu_iic_regs(np[0]);
+ cascade = node << IIC_IRQ_NODE_SHIFT;
+ cascade |= 1 << IIC_IRQ_CLASS_SHIFT;
+ cascade |= IIC_UNIT_IIC;
+ cascade = irq_create_mapping(iic_host, cascade);
+ if (cascade == NO_IRQ)
+ continue;
+ /*
+ * irq_data is a generic pointer that gets passed back
+ * to us later, so the forced cast is fine.
+ */
+ irq_set_handler_data(cascade, (void __force *)node_iic);
+ irq_set_chained_handler(cascade, iic_ioexc_cascade);
+ out_be64(&node_iic->iic_ir,
+ (1 << 12) /* priority */ |
+ (node << 4) /* dest node */ |
+ IIC_UNIT_THREAD_0 /* route them to thread 0 */);
+ /* Flush pending (make sure it triggers if there is
+ * anything pending
+ */
+ out_be64(&node_iic->iic_is, 0xfffffffffffffffful);
+ }
+
+ if (found)
+ return 0;
+ else
+ return -ENODEV;
+}
+
+void __init iic_init_IRQ(void)
+{
+ /* Setup an irq host data structure */
+ iic_host = irq_domain_add_linear(NULL, IIC_SOURCE_COUNT, &iic_host_ops,
+ NULL);
+ BUG_ON(iic_host == NULL);
+ irq_set_default_host(iic_host);
+
+ /* Discover and initialize iics */
+ if (setup_iic() < 0)
+ panic("IIC: Failed to initialize !\n");
+
+ /* Set master interrupt handling function */
+ ppc_md.get_irq = iic_get_irq;
+
+ /* Enable on current CPU */
+ iic_setup_cpu();
+}
+
+void iic_set_interrupt_routing(int cpu, int thread, int priority)
+{
+ struct cbe_iic_regs __iomem *iic_regs = cbe_get_cpu_iic_regs(cpu);
+ u64 iic_ir = 0;
+ int node = cpu >> 1;
+
+ /* Set which node and thread will handle the next interrupt */
+ iic_ir |= CBE_IIC_IR_PRIO(priority) |
+ CBE_IIC_IR_DEST_NODE(node);
+ if (thread == 0)
+ iic_ir |= CBE_IIC_IR_DEST_UNIT(CBE_IIC_IR_PT_0);
+ else
+ iic_ir |= CBE_IIC_IR_DEST_UNIT(CBE_IIC_IR_PT_1);
+ out_be64(&iic_regs->iic_ir, iic_ir);
+}
Code Review / kvmfornfv.git / blobdiff