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Diffstat (limited to 'arch/x86/kernel/i8259_64.c')
-rw-r--r--arch/x86/kernel/i8259_64.c544
1 files changed, 544 insertions, 0 deletions
diff --git a/arch/x86/kernel/i8259_64.c b/arch/x86/kernel/i8259_64.c
new file mode 100644
index 00000000000..948cae64609
--- /dev/null
+++ b/arch/x86/kernel/i8259_64.c
@@ -0,0 +1,544 @@
+#include <linux/linkage.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/timex.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <linux/sysdev.h>
+#include <linux/bitops.h>
+
+#include <asm/acpi.h>
+#include <asm/atomic.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/hw_irq.h>
+#include <asm/pgtable.h>
+#include <asm/delay.h>
+#include <asm/desc.h>
+#include <asm/apic.h>
+
+/*
+ * Common place to define all x86 IRQ vectors
+ *
+ * This builds up the IRQ handler stubs using some ugly macros in irq.h
+ *
+ * These macros create the low-level assembly IRQ routines that save
+ * register context and call do_IRQ(). do_IRQ() then does all the
+ * operations that are needed to keep the AT (or SMP IOAPIC)
+ * interrupt-controller happy.
+ */
+
+#define BI(x,y) \
+ BUILD_IRQ(x##y)
+
+#define BUILD_16_IRQS(x) \
+ BI(x,0) BI(x,1) BI(x,2) BI(x,3) \
+ BI(x,4) BI(x,5) BI(x,6) BI(x,7) \
+ BI(x,8) BI(x,9) BI(x,a) BI(x,b) \
+ BI(x,c) BI(x,d) BI(x,e) BI(x,f)
+
+/*
+ * ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
+ * (these are usually mapped to vectors 0x30-0x3f)
+ */
+
+/*
+ * The IO-APIC gives us many more interrupt sources. Most of these
+ * are unused but an SMP system is supposed to have enough memory ...
+ * sometimes (mostly wrt. hw bugs) we get corrupted vectors all
+ * across the spectrum, so we really want to be prepared to get all
+ * of these. Plus, more powerful systems might have more than 64
+ * IO-APIC registers.
+ *
+ * (these are usually mapped into the 0x30-0xff vector range)
+ */
+ BUILD_16_IRQS(0x2) BUILD_16_IRQS(0x3)
+BUILD_16_IRQS(0x4) BUILD_16_IRQS(0x5) BUILD_16_IRQS(0x6) BUILD_16_IRQS(0x7)
+BUILD_16_IRQS(0x8) BUILD_16_IRQS(0x9) BUILD_16_IRQS(0xa) BUILD_16_IRQS(0xb)
+BUILD_16_IRQS(0xc) BUILD_16_IRQS(0xd) BUILD_16_IRQS(0xe) BUILD_16_IRQS(0xf)
+
+#undef BUILD_16_IRQS
+#undef BI
+
+
+#define IRQ(x,y) \
+ IRQ##x##y##_interrupt
+
+#define IRQLIST_16(x) \
+ IRQ(x,0), IRQ(x,1), IRQ(x,2), IRQ(x,3), \
+ IRQ(x,4), IRQ(x,5), IRQ(x,6), IRQ(x,7), \
+ IRQ(x,8), IRQ(x,9), IRQ(x,a), IRQ(x,b), \
+ IRQ(x,c), IRQ(x,d), IRQ(x,e), IRQ(x,f)
+
+/* for the irq vectors */
+static void (*interrupt[NR_VECTORS - FIRST_EXTERNAL_VECTOR])(void) = {
+ IRQLIST_16(0x2), IRQLIST_16(0x3),
+ IRQLIST_16(0x4), IRQLIST_16(0x5), IRQLIST_16(0x6), IRQLIST_16(0x7),
+ IRQLIST_16(0x8), IRQLIST_16(0x9), IRQLIST_16(0xa), IRQLIST_16(0xb),
+ IRQLIST_16(0xc), IRQLIST_16(0xd), IRQLIST_16(0xe), IRQLIST_16(0xf)
+};
+
+#undef IRQ
+#undef IRQLIST_16
+
+/*
+ * This is the 'legacy' 8259A Programmable Interrupt Controller,
+ * present in the majority of PC/AT boxes.
+ * plus some generic x86 specific things if generic specifics makes
+ * any sense at all.
+ * this file should become arch/i386/kernel/irq.c when the old irq.c
+ * moves to arch independent land
+ */
+
+static int i8259A_auto_eoi;
+DEFINE_SPINLOCK(i8259A_lock);
+static void mask_and_ack_8259A(unsigned int);
+
+static struct irq_chip i8259A_chip = {
+ .name = "XT-PIC",
+ .mask = disable_8259A_irq,
+ .disable = disable_8259A_irq,
+ .unmask = enable_8259A_irq,
+ .mask_ack = mask_and_ack_8259A,
+};
+
+/*
+ * 8259A PIC functions to handle ISA devices:
+ */
+
+/*
+ * This contains the irq mask for both 8259A irq controllers,
+ */
+static unsigned int cached_irq_mask = 0xffff;
+
+#define __byte(x,y) (((unsigned char *)&(y))[x])
+#define cached_21 (__byte(0,cached_irq_mask))
+#define cached_A1 (__byte(1,cached_irq_mask))
+
+/*
+ * Not all IRQs can be routed through the IO-APIC, eg. on certain (older)
+ * boards the timer interrupt is not really connected to any IO-APIC pin,
+ * it's fed to the master 8259A's IR0 line only.
+ *
+ * Any '1' bit in this mask means the IRQ is routed through the IO-APIC.
+ * this 'mixed mode' IRQ handling costs nothing because it's only used
+ * at IRQ setup time.
+ */
+unsigned long io_apic_irqs;
+
+void disable_8259A_irq(unsigned int irq)
+{
+ unsigned int mask = 1 << irq;
+ unsigned long flags;
+
+ spin_lock_irqsave(&i8259A_lock, flags);
+ cached_irq_mask |= mask;
+ if (irq & 8)
+ outb(cached_A1,0xA1);
+ else
+ outb(cached_21,0x21);
+ spin_unlock_irqrestore(&i8259A_lock, flags);
+}
+
+void enable_8259A_irq(unsigned int irq)
+{
+ unsigned int mask = ~(1 << irq);
+ unsigned long flags;
+
+ spin_lock_irqsave(&i8259A_lock, flags);
+ cached_irq_mask &= mask;
+ if (irq & 8)
+ outb(cached_A1,0xA1);
+ else
+ outb(cached_21,0x21);
+ spin_unlock_irqrestore(&i8259A_lock, flags);
+}
+
+int i8259A_irq_pending(unsigned int irq)
+{
+ unsigned int mask = 1<<irq;
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&i8259A_lock, flags);
+ if (irq < 8)
+ ret = inb(0x20) & mask;
+ else
+ ret = inb(0xA0) & (mask >> 8);
+ spin_unlock_irqrestore(&i8259A_lock, flags);
+
+ return ret;
+}
+
+void make_8259A_irq(unsigned int irq)
+{
+ disable_irq_nosync(irq);
+ io_apic_irqs &= ~(1<<irq);
+ set_irq_chip_and_handler_name(irq, &i8259A_chip, handle_level_irq,
+ "XT");
+ enable_irq(irq);
+}
+
+/*
+ * This function assumes to be called rarely. Switching between
+ * 8259A registers is slow.
+ * This has to be protected by the irq controller spinlock
+ * before being called.
+ */
+static inline int i8259A_irq_real(unsigned int irq)
+{
+ int value;
+ int irqmask = 1<<irq;
+
+ if (irq < 8) {
+ outb(0x0B,0x20); /* ISR register */
+ value = inb(0x20) & irqmask;
+ outb(0x0A,0x20); /* back to the IRR register */
+ return value;
+ }
+ outb(0x0B,0xA0); /* ISR register */
+ value = inb(0xA0) & (irqmask >> 8);
+ outb(0x0A,0xA0); /* back to the IRR register */
+ return value;
+}
+
+/*
+ * Careful! The 8259A is a fragile beast, it pretty
+ * much _has_ to be done exactly like this (mask it
+ * first, _then_ send the EOI, and the order of EOI
+ * to the two 8259s is important!
+ */
+static void mask_and_ack_8259A(unsigned int irq)
+{
+ unsigned int irqmask = 1 << irq;
+ unsigned long flags;
+
+ spin_lock_irqsave(&i8259A_lock, flags);
+ /*
+ * Lightweight spurious IRQ detection. We do not want
+ * to overdo spurious IRQ handling - it's usually a sign
+ * of hardware problems, so we only do the checks we can
+ * do without slowing down good hardware unnecessarily.
+ *
+ * Note that IRQ7 and IRQ15 (the two spurious IRQs
+ * usually resulting from the 8259A-1|2 PICs) occur
+ * even if the IRQ is masked in the 8259A. Thus we
+ * can check spurious 8259A IRQs without doing the
+ * quite slow i8259A_irq_real() call for every IRQ.
+ * This does not cover 100% of spurious interrupts,
+ * but should be enough to warn the user that there
+ * is something bad going on ...
+ */
+ if (cached_irq_mask & irqmask)
+ goto spurious_8259A_irq;
+ cached_irq_mask |= irqmask;
+
+handle_real_irq:
+ if (irq & 8) {
+ inb(0xA1); /* DUMMY - (do we need this?) */
+ outb(cached_A1,0xA1);
+ outb(0x60+(irq&7),0xA0);/* 'Specific EOI' to slave */
+ outb(0x62,0x20); /* 'Specific EOI' to master-IRQ2 */
+ } else {
+ inb(0x21); /* DUMMY - (do we need this?) */
+ outb(cached_21,0x21);
+ outb(0x60+irq,0x20); /* 'Specific EOI' to master */
+ }
+ spin_unlock_irqrestore(&i8259A_lock, flags);
+ return;
+
+spurious_8259A_irq:
+ /*
+ * this is the slow path - should happen rarely.
+ */
+ if (i8259A_irq_real(irq))
+ /*
+ * oops, the IRQ _is_ in service according to the
+ * 8259A - not spurious, go handle it.
+ */
+ goto handle_real_irq;
+
+ {
+ static int spurious_irq_mask;
+ /*
+ * At this point we can be sure the IRQ is spurious,
+ * lets ACK and report it. [once per IRQ]
+ */
+ if (!(spurious_irq_mask & irqmask)) {
+ printk(KERN_DEBUG "spurious 8259A interrupt: IRQ%d.\n", irq);
+ spurious_irq_mask |= irqmask;
+ }
+ atomic_inc(&irq_err_count);
+ /*
+ * Theoretically we do not have to handle this IRQ,
+ * but in Linux this does not cause problems and is
+ * simpler for us.
+ */
+ goto handle_real_irq;
+ }
+}
+
+void init_8259A(int auto_eoi)
+{
+ unsigned long flags;
+
+ i8259A_auto_eoi = auto_eoi;
+
+ spin_lock_irqsave(&i8259A_lock, flags);
+
+ outb(0xff, 0x21); /* mask all of 8259A-1 */
+ outb(0xff, 0xA1); /* mask all of 8259A-2 */
+
+ /*
+ * outb_p - this has to work on a wide range of PC hardware.
+ */
+ outb_p(0x11, 0x20); /* ICW1: select 8259A-1 init */
+ outb_p(IRQ0_VECTOR, 0x21); /* ICW2: 8259A-1 IR0-7 mapped to 0x30-0x37 */
+ outb_p(0x04, 0x21); /* 8259A-1 (the master) has a slave on IR2 */
+ if (auto_eoi)
+ outb_p(0x03, 0x21); /* master does Auto EOI */
+ else
+ outb_p(0x01, 0x21); /* master expects normal EOI */
+
+ outb_p(0x11, 0xA0); /* ICW1: select 8259A-2 init */
+ outb_p(IRQ8_VECTOR, 0xA1); /* ICW2: 8259A-2 IR0-7 mapped to 0x38-0x3f */
+ outb_p(0x02, 0xA1); /* 8259A-2 is a slave on master's IR2 */
+ outb_p(0x01, 0xA1); /* (slave's support for AEOI in flat mode
+ is to be investigated) */
+
+ if (auto_eoi)
+ /*
+ * in AEOI mode we just have to mask the interrupt
+ * when acking.
+ */
+ i8259A_chip.mask_ack = disable_8259A_irq;
+ else
+ i8259A_chip.mask_ack = mask_and_ack_8259A;
+
+ udelay(100); /* wait for 8259A to initialize */
+
+ outb(cached_21, 0x21); /* restore master IRQ mask */
+ outb(cached_A1, 0xA1); /* restore slave IRQ mask */
+
+ spin_unlock_irqrestore(&i8259A_lock, flags);
+}
+
+static char irq_trigger[2];
+/**
+ * ELCR registers (0x4d0, 0x4d1) control edge/level of IRQ
+ */
+static void restore_ELCR(char *trigger)
+{
+ outb(trigger[0], 0x4d0);
+ outb(trigger[1], 0x4d1);
+}
+
+static void save_ELCR(char *trigger)
+{
+ /* IRQ 0,1,2,8,13 are marked as reserved */
+ trigger[0] = inb(0x4d0) & 0xF8;
+ trigger[1] = inb(0x4d1) & 0xDE;
+}
+
+static int i8259A_resume(struct sys_device *dev)
+{
+ init_8259A(i8259A_auto_eoi);
+ restore_ELCR(irq_trigger);
+ return 0;
+}
+
+static int i8259A_suspend(struct sys_device *dev, pm_message_t state)
+{
+ save_ELCR(irq_trigger);
+ return 0;
+}
+
+static int i8259A_shutdown(struct sys_device *dev)
+{
+ /* Put the i8259A into a quiescent state that
+ * the kernel initialization code can get it
+ * out of.
+ */
+ outb(0xff, 0x21); /* mask all of 8259A-1 */
+ outb(0xff, 0xA1); /* mask all of 8259A-1 */
+ return 0;
+}
+
+static struct sysdev_class i8259_sysdev_class = {
+ set_kset_name("i8259"),
+ .suspend = i8259A_suspend,
+ .resume = i8259A_resume,
+ .shutdown = i8259A_shutdown,
+};
+
+static struct sys_device device_i8259A = {
+ .id = 0,
+ .cls = &i8259_sysdev_class,
+};
+
+static int __init i8259A_init_sysfs(void)
+{
+ int error = sysdev_class_register(&i8259_sysdev_class);
+ if (!error)
+ error = sysdev_register(&device_i8259A);
+ return error;
+}
+
+device_initcall(i8259A_init_sysfs);
+
+/*
+ * IRQ2 is cascade interrupt to second interrupt controller
+ */
+
+static struct irqaction irq2 = { no_action, 0, CPU_MASK_NONE, "cascade", NULL, NULL};
+DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
+ [0 ... IRQ0_VECTOR - 1] = -1,
+ [IRQ0_VECTOR] = 0,
+ [IRQ1_VECTOR] = 1,
+ [IRQ2_VECTOR] = 2,
+ [IRQ3_VECTOR] = 3,
+ [IRQ4_VECTOR] = 4,
+ [IRQ5_VECTOR] = 5,
+ [IRQ6_VECTOR] = 6,
+ [IRQ7_VECTOR] = 7,
+ [IRQ8_VECTOR] = 8,
+ [IRQ9_VECTOR] = 9,
+ [IRQ10_VECTOR] = 10,
+ [IRQ11_VECTOR] = 11,
+ [IRQ12_VECTOR] = 12,
+ [IRQ13_VECTOR] = 13,
+ [IRQ14_VECTOR] = 14,
+ [IRQ15_VECTOR] = 15,
+ [IRQ15_VECTOR + 1 ... NR_VECTORS - 1] = -1
+};
+
+void __init init_ISA_irqs (void)
+{
+ int i;
+
+ init_bsp_APIC();
+ init_8259A(0);
+
+ for (i = 0; i < NR_IRQS; i++) {
+ irq_desc[i].status = IRQ_DISABLED;
+ irq_desc[i].action = NULL;
+ irq_desc[i].depth = 1;
+
+ if (i < 16) {
+ /*
+ * 16 old-style INTA-cycle interrupts:
+ */
+ set_irq_chip_and_handler_name(i, &i8259A_chip,
+ handle_level_irq, "XT");
+ } else {
+ /*
+ * 'high' PCI IRQs filled in on demand
+ */
+ irq_desc[i].chip = &no_irq_chip;
+ }
+ }
+}
+
+static void setup_timer_hardware(void)
+{
+ outb_p(0x34,0x43); /* binary, mode 2, LSB/MSB, ch 0 */
+ udelay(10);
+ outb_p(LATCH & 0xff , 0x40); /* LSB */
+ udelay(10);
+ outb(LATCH >> 8 , 0x40); /* MSB */
+}
+
+static int timer_resume(struct sys_device *dev)
+{
+ setup_timer_hardware();
+ return 0;
+}
+
+void i8254_timer_resume(void)
+{
+ setup_timer_hardware();
+}
+
+static struct sysdev_class timer_sysclass = {
+ set_kset_name("timer_pit"),
+ .resume = timer_resume,
+};
+
+static struct sys_device device_timer = {
+ .id = 0,
+ .cls = &timer_sysclass,
+};
+
+static int __init init_timer_sysfs(void)
+{
+ int error = sysdev_class_register(&timer_sysclass);
+ if (!error)
+ error = sysdev_register(&device_timer);
+ return error;
+}
+
+device_initcall(init_timer_sysfs);
+
+void __init init_IRQ(void)
+{
+ int i;
+
+ init_ISA_irqs();
+ /*
+ * Cover the whole vector space, no vector can escape
+ * us. (some of these will be overridden and become
+ * 'special' SMP interrupts)
+ */
+ for (i = 0; i < (NR_VECTORS - FIRST_EXTERNAL_VECTOR); i++) {
+ int vector = FIRST_EXTERNAL_VECTOR + i;
+ if (vector != IA32_SYSCALL_VECTOR)
+ set_intr_gate(vector, interrupt[i]);
+ }
+
+#ifdef CONFIG_SMP
+ /*
+ * The reschedule interrupt is a CPU-to-CPU reschedule-helper
+ * IPI, driven by wakeup.
+ */
+ set_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
+
+ /* IPIs for invalidation */
+ set_intr_gate(INVALIDATE_TLB_VECTOR_START+0, invalidate_interrupt0);
+ set_intr_gate(INVALIDATE_TLB_VECTOR_START+1, invalidate_interrupt1);
+ set_intr_gate(INVALIDATE_TLB_VECTOR_START+2, invalidate_interrupt2);
+ set_intr_gate(INVALIDATE_TLB_VECTOR_START+3, invalidate_interrupt3);
+ set_intr_gate(INVALIDATE_TLB_VECTOR_START+4, invalidate_interrupt4);
+ set_intr_gate(INVALIDATE_TLB_VECTOR_START+5, invalidate_interrupt5);
+ set_intr_gate(INVALIDATE_TLB_VECTOR_START+6, invalidate_interrupt6);
+ set_intr_gate(INVALIDATE_TLB_VECTOR_START+7, invalidate_interrupt7);
+
+ /* IPI for generic function call */
+ set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
+
+ /* Low priority IPI to cleanup after moving an irq */
+ set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
+#endif
+ set_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
+ set_intr_gate(THRESHOLD_APIC_VECTOR, threshold_interrupt);
+
+ /* self generated IPI for local APIC timer */
+ set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
+
+ /* IPI vectors for APIC spurious and error interrupts */
+ set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
+ set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
+
+ /*
+ * Set the clock to HZ Hz, we already have a valid
+ * vector now:
+ */
+ setup_timer_hardware();
+
+ if (!acpi_ioapic)
+ setup_irq(2, &irq2);
+}