diff options
Diffstat (limited to 'arch/ppc64/kernel/bpa_iic.c')
| -rw-r--r-- | arch/ppc64/kernel/bpa_iic.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/bpa_iic.c b/arch/ppc64/kernel/bpa_iic.c new file mode 100644 index 00000000000..c8f3dc3fad7 --- /dev/null +++ b/arch/ppc64/kernel/bpa_iic.c @@ -0,0 +1,270 @@ +/* + * BPA 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 "bpa_iic.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 = " BPA-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 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 +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, mesg); +} + +static irqreturn_t iic_ipi_action(int irq, void *dev_id, struct pt_regs *regs) +{ + + smp_message_recv(irq - IIC_IPI_OFFSET, regs); + return IRQ_HANDLED; +} + +static void iic_request_ipi(int irq, const char *name) +{ + /* 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(IIC_IPI_OFFSET + PPC_MSG_CALL_FUNCTION, "IPI-call"); + iic_request_ipi(IIC_IPI_OFFSET + PPC_MSG_RESCHEDULE, "IPI-resched"); +#ifdef CONFIG_DEBUGGER + iic_request_ipi(IIC_IPI_OFFSET + 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(); +} |