aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/platforms/cell/interrupt.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/platforms/cell/interrupt.c')
-rw-r--r--arch/powerpc/platforms/cell/interrupt.c284
1 files changed, 284 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/cell/interrupt.c b/arch/powerpc/platforms/cell/interrupt.c
new file mode 100644
index 000000000000..7fbe78a9327d
--- /dev/null
+++ b/arch/powerpc/platforms/cell/interrupt.c
@@ -0,0 +1,284 @@
+/*
+ * Cell Internal Interrupt Controller
+ *
+ * (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.
+ */
+
+#include <linux/config.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/percpu.h>
+#include <linux/types.h>
+
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/prom.h>
+#include <asm/ptrace.h>
+
+#include "interrupt.h"
+
+struct iic_pending_bits {
+ u32 data;
+ u8 flags;
+ u8 class;
+ u8 source;
+ u8 prio;
+};
+
+enum iic_pending_flags {
+ IIC_VALID = 0x80,
+ IIC_IPI = 0x40,
+};
+
+struct iic_regs {
+ struct iic_pending_bits pending;
+ struct iic_pending_bits pending_destr;
+ u64 generate;
+ u64 prio;
+};
+
+struct iic {
+ struct iic_regs __iomem *regs;
+};
+
+static DEFINE_PER_CPU(struct iic, iic);
+
+void iic_local_enable(void)
+{
+ out_be64(&__get_cpu_var(iic).regs->prio, 0xff);
+}
+
+void iic_local_disable(void)
+{
+ out_be64(&__get_cpu_var(iic).regs->prio, 0x0);
+}
+
+static unsigned int iic_startup(unsigned int irq)
+{
+ return 0;
+}
+
+static void iic_enable(unsigned int irq)
+{
+ iic_local_enable();
+}
+
+static void iic_disable(unsigned int irq)
+{
+}
+
+static void iic_end(unsigned int irq)
+{
+ iic_local_enable();
+}
+
+static struct hw_interrupt_type iic_pic = {
+ .typename = " CELL-IIC ",
+ .startup = iic_startup,
+ .enable = iic_enable,
+ .disable = iic_disable,
+ .end = iic_end,
+};
+
+static int iic_external_get_irq(struct iic_pending_bits pending)
+{
+ int irq;
+ unsigned char node, unit;
+
+ node = pending.source >> 4;
+ unit = pending.source & 0xf;
+ irq = -1;
+
+ /*
+ * This mapping is specific to the Cell Broadband
+ * Engine. We might need to get the numbers
+ * from the device tree to support future CPUs.
+ */
+ switch (unit) {
+ case 0x00:
+ case 0x0b:
+ /*
+ * One of these units can be connected
+ * to an external interrupt controller.
+ */
+ if (pending.prio > 0x3f ||
+ pending.class != 2)
+ break;
+ irq = IIC_EXT_OFFSET
+ + spider_get_irq(pending.prio + node * IIC_NODE_STRIDE)
+ + node * IIC_NODE_STRIDE;
+ break;
+ case 0x01 ... 0x04:
+ case 0x07 ... 0x0a:
+ /*
+ * These units are connected to the SPEs
+ */
+ if (pending.class > 2)
+ break;
+ irq = IIC_SPE_OFFSET
+ + pending.class * IIC_CLASS_STRIDE
+ + node * IIC_NODE_STRIDE
+ + unit;
+ break;
+ }
+ if (irq == -1)
+ printk(KERN_WARNING "Unexpected interrupt class %02x, "
+ "source %02x, prio %02x, cpu %02x\n", pending.class,
+ pending.source, pending.prio, smp_processor_id());
+ return irq;
+}
+
+/* Get an IRQ number from the pending state register of the IIC */
+int iic_get_irq(struct pt_regs *regs)
+{
+ struct iic *iic;
+ int irq;
+ struct iic_pending_bits pending;
+
+ iic = &__get_cpu_var(iic);
+ *(unsigned long *) &pending =
+ in_be64((unsigned long __iomem *) &iic->regs->pending_destr);
+
+ irq = -1;
+ if (pending.flags & IIC_VALID) {
+ if (pending.flags & IIC_IPI) {
+ irq = IIC_IPI_OFFSET + (pending.prio >> 4);
+/*
+ if (irq > 0x80)
+ printk(KERN_WARNING "Unexpected IPI prio %02x"
+ "on CPU %02x\n", pending.prio,
+ smp_processor_id());
+*/
+ } else {
+ irq = iic_external_get_irq(pending);
+ }
+ }
+ return irq;
+}
+
+static struct iic_regs __iomem *find_iic(int cpu)
+{
+ struct device_node *np;
+ int nodeid = cpu / 2;
+ unsigned long regs;
+ struct iic_regs __iomem *iic_regs;
+
+ for (np = of_find_node_by_type(NULL, "cpu");
+ np;
+ np = of_find_node_by_type(np, "cpu")) {
+ if (nodeid == *(int *)get_property(np, "node-id", NULL))
+ break;
+ }
+
+ if (!np) {
+ printk(KERN_WARNING "IIC: CPU %d not found\n", cpu);
+ iic_regs = NULL;
+ } else {
+ regs = *(long *)get_property(np, "iic", NULL);
+
+ /* hack until we have decided on the devtree info */
+ regs += 0x400;
+ if (cpu & 1)
+ regs += 0x20;
+
+ printk(KERN_DEBUG "IIC for CPU %d at %lx\n", cpu, regs);
+ iic_regs = __ioremap(regs, sizeof(struct iic_regs),
+ _PAGE_NO_CACHE);
+ }
+ return iic_regs;
+}
+
+#ifdef CONFIG_SMP
+
+/* Use the highest interrupt priorities for IPI */
+static inline int iic_ipi_to_irq(int ipi)
+{
+ return IIC_IPI_OFFSET + IIC_NUM_IPIS - 1 - ipi;
+}
+
+static inline int iic_irq_to_ipi(int irq)
+{
+ return IIC_NUM_IPIS - 1 - (irq - IIC_IPI_OFFSET);
+}
+
+void iic_setup_cpu(void)
+{
+ out_be64(&__get_cpu_var(iic).regs->prio, 0xff);
+}
+
+void iic_cause_IPI(int cpu, int mesg)
+{
+ out_be64(&per_cpu(iic, cpu).regs->generate, (IIC_NUM_IPIS - 1 - mesg) << 4);
+}
+
+static irqreturn_t iic_ipi_action(int irq, void *dev_id, struct pt_regs *regs)
+{
+ smp_message_recv(iic_irq_to_ipi(irq), regs);
+ return IRQ_HANDLED;
+}
+
+static void iic_request_ipi(int ipi, const char *name)
+{
+ int irq;
+
+ irq = iic_ipi_to_irq(ipi);
+ /* IPIs are marked SA_INTERRUPT as they must run with irqs
+ * disabled */
+ get_irq_desc(irq)->handler = &iic_pic;
+ get_irq_desc(irq)->status |= IRQ_PER_CPU;
+ request_irq(irq, iic_ipi_action, SA_INTERRUPT, name, NULL);
+}
+
+void iic_request_IPIs(void)
+{
+ iic_request_ipi(PPC_MSG_CALL_FUNCTION, "IPI-call");
+ iic_request_ipi(PPC_MSG_RESCHEDULE, "IPI-resched");
+#ifdef CONFIG_DEBUGGER
+ iic_request_ipi(PPC_MSG_DEBUGGER_BREAK, "IPI-debug");
+#endif /* CONFIG_DEBUGGER */
+}
+#endif /* CONFIG_SMP */
+
+static void iic_setup_spe_handlers(void)
+{
+ int be, isrc;
+
+ /* Assume two threads per BE are present */
+ for (be=0; be < num_present_cpus() / 2; be++) {
+ for (isrc = 0; isrc < IIC_CLASS_STRIDE * 3; isrc++) {
+ int irq = IIC_NODE_STRIDE * be + IIC_SPE_OFFSET + isrc;
+ get_irq_desc(irq)->handler = &iic_pic;
+ }
+ }
+}
+
+void iic_init_IRQ(void)
+{
+ int cpu, irq_offset;
+ struct iic *iic;
+
+ irq_offset = 0;
+ for_each_cpu(cpu) {
+ iic = &per_cpu(iic, cpu);
+ iic->regs = find_iic(cpu);
+ if (iic->regs)
+ out_be64(&iic->regs->prio, 0xff);
+ }
+ iic_setup_spe_handlers();
+}

Privacy Policy