diff options
Diffstat (limited to 'target/linux/ubicom32/files/arch/ubicom32/kernel/irq.c')
| -rw-r--r-- | target/linux/ubicom32/files/arch/ubicom32/kernel/irq.c | 597 |
1 files changed, 0 insertions, 597 deletions
diff --git a/target/linux/ubicom32/files/arch/ubicom32/kernel/irq.c b/target/linux/ubicom32/files/arch/ubicom32/kernel/irq.c deleted file mode 100644 index c041f23e25..0000000000 --- a/target/linux/ubicom32/files/arch/ubicom32/kernel/irq.c +++ /dev/null @@ -1,597 +0,0 @@ -/* - * arch/ubicom32/kernel/irq.c - * Ubicom32 architecture IRQ support. - * - * (C) Copyright 2009, Ubicom, Inc. - * (C) Copyright 2007, Greg Ungerer <gerg@snapgear.com> - * - * This file is part of the Ubicom32 Linux Kernel Port. - * - * The Ubicom32 Linux Kernel Port 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. - * - * The Ubicom32 Linux Kernel Port 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 the Ubicom32 Linux Kernel Port. If not, - * see <http://www.gnu.org/licenses/>. - * - * Ubicom32 implementation derived from (with many thanks): - * arch/m68knommu - * arch/blackfin - * arch/parisc - */ - -#include <linux/types.h> -#include <linux/irq.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/kernel_stat.h> -#include <linux/module.h> -#include <linux/seq_file.h> -#include <linux/proc_fs.h> -#include <asm/system.h> -#include <asm/traps.h> -#include <asm/ldsr.h> -#include <asm/ip5000.h> -#include <asm/machdep.h> -#include <asm/asm-offsets.h> -#include <asm/thread.h> -#include <asm/devtree.h> - -unsigned int irq_soft_avail; -static struct irqaction ubicom32_reserve_action[NR_IRQS]; - -#if !defined(CONFIG_DEBUG_IRQMEASURE) -#define IRQ_DECLARE_MEASUREMENT -#define IRQ_MEASUREMENT_START() -#define IRQ_MEASUREMENT_END(irq) -#else -#define IRQ_DECLARE_MEASUREMENT \ - int __diff; \ - unsigned int __tstart; - -#define IRQ_MEASUREMENT_START() \ - __tstart = UBICOM32_IO_TIMER->sysval; - -#define IRQ_MEASUREMENT_END(irq) \ - __diff = (int)UBICOM32_IO_TIMER->sysval - (int)__tstart; \ - irq_measurement_update((irq), __diff); - -/* - * We keep track of the time spent in both irq_enter() - * and irq_exit(). - */ -#define IRQ_WEIGHT 32 - -struct irq_measurement { - volatile unsigned int min; - volatile unsigned int avg; - volatile unsigned int max; -}; - -static DEFINE_SPINLOCK(irq_measurement_lock); - -/* - * Add 1 in for softirq (irq_exit()); - */ -static struct irq_measurement irq_measurements[NR_IRQS + 1]; - -/* - * irq_measurement_update() - * Update an entry in the measurement array for this irq. - */ -static void irq_measurement_update(int irq, int sample) -{ - struct irq_measurement *im = &irq_measurements[irq]; - spin_lock(&irq_measurement_lock); - if ((im->min == 0) || (im->min > sample)) { - im->min = sample; - } - if (im->max < sample) { - im->max = sample; - } - im->avg = ((im->avg * (IRQ_WEIGHT - 1)) + sample) / IRQ_WEIGHT; - spin_unlock(&irq_measurement_lock); -} -#endif - -/* - * irq_kernel_stack_check() - * See if the kernel stack is within STACK_WARN of the end. - */ -static void irq_kernel_stack_check(int irq, struct pt_regs *regs) -{ -#ifdef CONFIG_DEBUG_STACKOVERFLOW - unsigned long sp; - - /* - * Make sure that we are not close to the top of the stack and thus - * can not really service this interrupt. - */ - asm volatile ( - "and.4 %0, SP, %1 \n\t" - : "=d" (sp) - : "d" (THREAD_SIZE - 1) - : "cc" - ); - - if (sp < (sizeof(struct thread_info) + STACK_WARN)) { - printk(KERN_WARNING - "cpu[%d]: possible overflow detected sp remain: %p, " - "irq: %d, regs: %p\n", - thread_get_self(), (void *)sp, irq, regs); - dump_stack(); - } - - if (sp < (sizeof(struct thread_info) + 16)) { - THREAD_STALL; - } -#endif -} - -/* - * irq_get_lsb() - * Get the LSB set in value - */ -static int irq_get_lsb(unsigned int value) -{ - static unsigned char irq_bits[8] = { - 3, 0, 1, 0, 2, 0, 1, 0 - }; - u32_t nextbit = 0; - - value = (value >> nextbit) | (value << ((sizeof(value) * 8) - nextbit)); - - /* - * It's unlikely that we find that we execute the body of this while - * loop. 50% of the time we won't take this at all and then of the - * cases where we do about 50% of those we only execute once. - */ - if (!(value & 0xffff)) { - nextbit += 0x10; - value >>= 16; - } - - if (!(value & 0xff)) { - nextbit += 0x08; - value >>= 8; - } - - if (!(value & 0xf)) { - nextbit += 0x04; - value >>= 4; - } - - nextbit += irq_bits[value & 0x7]; - if (nextbit > 63) { - panic("nextbit out of range: %d\n", nextbit); - } - return nextbit; -} - -/* - * ubicom32_reserve_handler() - * Bogus handler associated with pre-reserved IRQ(s). - */ -static irqreturn_t ubicom32_reserve_handler(int irq, void *dev_id) -{ - BUG(); - return IRQ_HANDLED; -} - -/* - * __irq_disable_vector() - * Disable the interrupt by clearing the appropriate bit in the - * LDSR Mask Register. - */ -static void __irq_disable_vector(unsigned int irq) -{ - ldsr_disable_vector(irq); -} - -/* - * __irq_ack_vector() - * Acknowledge the specific interrupt by clearing the associate bit in - * hardware - */ -static void __irq_ack_vector(unsigned int irq) -{ - if (irq < 32) { - asm volatile ("move.4 INT_CLR0, %0" : : "d" (1 << irq)); - } else { - asm volatile ("move.4 INT_CLR1, %0" : : "d" (1 << (irq - 32))); - } -} - -/* - * __irq_enable_vector() - * Clean and then enable the interrupt by setting the appropriate bit in - * the LDSR Mask Register. - */ -static void __irq_enable_vector(unsigned int irq) -{ - /* - * Acknowledge, really clear the vector. - */ - __irq_ack_vector(irq); - ldsr_enable_vector(irq); -} - -/* - * __irq_mask_vector() - */ -static void __irq_mask_vector(unsigned int irq) -{ - ldsr_mask_vector(irq); -} - -/* - * __irq_unmask_vector() - */ -static void __irq_unmask_vector(unsigned int irq) -{ - ldsr_unmask_vector(irq); -} - -/* - * __irq_end_vector() - * Called once an interrupt is completed (reset the LDSR mask). - */ -static void __irq_end_vector(unsigned int irq) -{ - ldsr_unmask_vector(irq); -} - -#if defined(CONFIG_SMP) -/* - * __irq_set_affinity() - * Set the cpu affinity for this interrupt. - * affinity container allocated at boot - */ -static void __irq_set_affinity(unsigned int irq, const struct cpumask *dest) -{ - smp_set_affinity(irq, dest); - cpumask_copy(irq_desc[irq].affinity, dest); -} -#endif - -/* - * On-Chip Generic Interrupt function handling. - */ -static struct irq_chip ubicom32_irq_chip = { - .name = "Ubicom32", - .startup = NULL, - .shutdown = NULL, - .enable = __irq_enable_vector, - .disable = __irq_disable_vector, - .ack = __irq_ack_vector, - .mask = __irq_mask_vector, - .unmask = __irq_unmask_vector, - .end = __irq_end_vector, -#if defined(CONFIG_SMP) - .set_affinity = __irq_set_affinity, -#endif -}; - -/* - * do_IRQ() - * Primary interface for handling IRQ() requests. - */ -asmlinkage void do_IRQ(int irq, struct pt_regs *regs) -{ - struct pt_regs *oldregs; - struct thread_info *ti = current_thread_info(); - - IRQ_DECLARE_MEASUREMENT; - - /* - * Mark that we are inside of an interrupt and - * that interrupts are disabled. - */ - oldregs = set_irq_regs(regs); - ti->interrupt_nesting++; - trace_hardirqs_off(); - irq_kernel_stack_check(irq, regs); - - /* - * Start the interrupt sequence - */ - irq_enter(); - - /* - * Execute the IRQ handler and any pending SoftIRQ requests. - */ - BUG_ON(!irqs_disabled()); - IRQ_MEASUREMENT_START(); - __do_IRQ(irq); - IRQ_MEASUREMENT_END(irq); - BUG_ON(!irqs_disabled()); - - /* - * TODO: Since IRQ's are disabled when calling irq_exit() - * modify Kconfig to set __ARCH_IRQ_EXIT_IRQS_DISABLED flag. - * This will slightly improve performance by enabling - * softirq handling to avoid disabling/disabled interrupts. - */ - IRQ_MEASUREMENT_START(); - irq_exit(); - IRQ_MEASUREMENT_END(NR_IRQS); - BUG_ON(!irqs_disabled()); - - /* - * Outside of an interrupt (or nested exit). - */ - set_irq_regs(oldregs); - trace_hardirqs_on(); - ti->interrupt_nesting--; -} - -/* - * irq_soft_alloc() - * Allocate a soft IRQ. - */ -int irq_soft_alloc(unsigned int *soft) -{ - if (irq_soft_avail == 0) { - printk(KERN_NOTICE "no soft irqs to allocate\n"); - return -EFAULT; - } - - *soft = irq_get_lsb(irq_soft_avail); - irq_soft_avail &= ~(1 << *soft); - return 0; -} - -/* - * ack_bad_irq() - * Called to handle an bad irq request. - */ -void ack_bad_irq(unsigned int irq) -{ - printk(KERN_ERR "IRQ: unexpected irq=%d\n", irq); - __irq_end_vector(irq); -} - -/* - * show_interrupts() - * Return a string that displays the state of each of the interrupts. - */ -int show_interrupts(struct seq_file *p, void *v) -{ - struct irqaction *ap; - int irq = *((loff_t *) v); - int j; - - if (irq >= NR_IRQS) { - return 0; - } - - if (irq == 0) { - seq_puts(p, " "); - for_each_online_cpu(j) { - seq_printf(p, "CPU%d ", j); - } - seq_putc(p, '\n'); - } - - ap = irq_desc[irq].action; - if (ap) { - seq_printf(p, "%3d: ", irq); - for_each_online_cpu(j) { - seq_printf(p, "%10u ", kstat_irqs_cpu(irq, j)); - } - seq_printf(p, "%14s ", irq_desc[irq].chip->name); - seq_printf(p, "%s", ap->name); - for (ap = ap->next; ap; ap = ap->next) { - seq_printf(p, ", %s", ap->name); - } - seq_putc(p, '\n'); - } - return 0; -} - -#if defined(CONFIG_DEBUG_IRQMEASURE) -static unsigned int irq_cycles_to_micro(unsigned int cycles, unsigned int frequency) -{ - unsigned int micro = (cycles / (frequency / 1000000)); - return micro; -} - -/* - * irq_measurement_show() - * Print out the min, avg, max values for each IRQ - * - * By request, the max value is reset after each dump. - */ -static int irq_measurement_show(struct seq_file *p, void *v) -{ - struct irqaction *ap; - unsigned int freq = processor_frequency(); - int irq = *((loff_t *) v); - - - if (irq == 0) { - seq_puts(p, "\tmin\tavg\tmax\t(micro-seconds)\n"); - } - - if (irq > NR_IRQS) { - return 0; - } - - if (irq == NR_IRQS) { - unsigned int min, avg, max; - spin_lock(&irq_measurement_lock); - min = irq_cycles_to_micro(irq_measurements[irq].min, freq); - avg = irq_cycles_to_micro(irq_measurements[irq].avg, freq); - max = irq_cycles_to_micro(irq_measurements[irq].max, freq); - irq_measurements[irq].max = 0; - spin_unlock(&irq_measurement_lock); - seq_printf(p, " \t%u\t%u\t%u\tsoftirq\n", min, avg, max); - return 0; - } - - ap = irq_desc[irq].action; - if (ap) { - unsigned int min, avg, max; - spin_lock(&irq_measurement_lock); - min = irq_cycles_to_micro(irq_measurements[irq].min, freq); - avg = irq_cycles_to_micro(irq_measurements[irq].avg, freq); - max = irq_cycles_to_micro(irq_measurements[irq].max, freq); - irq_measurements[irq].max = 0; - spin_unlock(&irq_measurement_lock); - seq_printf(p, "%2u:\t%u\t%u\t%u\t%s\n", irq, min, avg, max, ap->name); - } - return 0; -} - -static void *irq_measurement_start(struct seq_file *f, loff_t *pos) -{ - return (*pos <= NR_IRQS) ? pos : NULL; -} - -static void *irq_measurement_next(struct seq_file *f, void *v, loff_t *pos) -{ - (*pos)++; - if (*pos > NR_IRQS) - return NULL; - return pos; -} - -static void irq_measurement_stop(struct seq_file *f, void *v) -{ - /* Nothing to do */ -} - -static const struct seq_operations irq_measurement_seq_ops = { - .start = irq_measurement_start, - .next = irq_measurement_next, - .stop = irq_measurement_stop, - .show = irq_measurement_show, -}; - -static int irq_measurement_open(struct inode *inode, struct file *filp) -{ - return seq_open(filp, &irq_measurement_seq_ops); -} - -static const struct file_operations irq_measurement_fops = { - .open = irq_measurement_open, - .read = seq_read, - .llseek = seq_lseek, - .release = seq_release, -}; - -static int __init irq_measurement_init(void) -{ - proc_create("irq_measurements", 0, NULL, &irq_measurement_fops); - return 0; -} -module_init(irq_measurement_init); -#endif - -/* - * init_IRQ(void) - * Initialize the on-chip IRQ subsystem. - */ -void __init init_IRQ(void) -{ - int irq; - struct devtree_node *p = NULL; - struct devtree_node *iter = NULL; - unsigned int mask = 0; - unsigned int reserved = 0; - - /* - * Pull out the list of software interrupts that are avialable to - * Linux and provide an allocation function for them. The first - * 24 interrupts of INT0 are software interrupts. - */ - irq_soft_avail = 0; - if (processor_interrupts(&irq_soft_avail, NULL) < 0) { - printk(KERN_WARNING "No Soft IRQ(s) available\n"); - } - irq_soft_avail &= ((1 << 24) - 1); - - /* - * Initialize all of the on-chip interrupt handling - * to use a common set of interrupt functions. - */ - for (irq = 0; irq < NR_IRQS; irq++) { - irq_desc[irq].status = IRQ_DISABLED; - irq_desc[irq].action = NULL; - irq_desc[irq].depth = 1; - set_irq_chip(irq, &ubicom32_irq_chip); - } - - /* - * The sendirq of a devnode is not registered within Linux but instead - * is used by the software I/O thread. These interrupts are reserved. - * The recvirq is used by Linux and registered by a device driver, these - * are not reserved. - * - * recvirq(s) that are in the software interrupt range are not supposed - * to be marked as reserved. We track this while we scan the device - * nodes. - */ - p = devtree_find_next(&iter); - while (p) { - unsigned char sendirq, recvirq; - devtree_irq(p, &sendirq, &recvirq); - - /* - * If the sendirq is valid, mark that irq as taken by the - * devtree node. - */ - if (sendirq < NR_IRQS) { - ubicom32_reserve_action[sendirq].handler = - ubicom32_reserve_handler; - ubicom32_reserve_action[sendirq].name = p->name; - irq_desc[sendirq].action = - &ubicom32_reserve_action[sendirq]; - mask |= (1 << sendirq); - } - - /* - * Track the relevant recieve IRQ(s) - */ - if (recvirq < 24) { - mask |= (1 << recvirq); - } - - /* - * Move to the next node. - */ - p = devtree_find_next(&iter); - } - - /* - * Remove these bits from the irq_soft_avail list and then use the - * result as the list of pre-reserved IRQ(s). - */ - reserved = ~irq_soft_avail & ~mask; - for (irq = 0; irq < 24; irq++) { - if ((reserved & (1 << irq))) { - ubicom32_reserve_action[irq].handler = - ubicom32_reserve_handler; - ubicom32_reserve_action[irq].name = "reserved"; - irq_desc[irq].action = &ubicom32_reserve_action[irq]; - } - } - - /* - * Initialize the LDSR which is the Ubicom32 programmable - * interrupt controller. - */ - ldsr_init(); - - /* - * The Ubicom trap code needs a 2nd init after IRQ(s) are setup. - */ - trap_init_interrupt(); -} |