Initial import

1 files changed, 520 insertions, 0 deletions

diff --git a/arch/cris/arch-v32/kernel/irq.c b/arch/cris/arch-v32/kernel/irq.c
new file mode 100644
index 000000000..6a881e0e9
--- /dev/null
+++ b/arch/cris/arch-v32/kernel/irq.c
@@ -0,0 +1,520 @@
+/*
+ * Copyright (C) 2003, Axis Communications AB.
+ */
+
+#include <asm/irq.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/smp.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/profile.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/threads.h>
+#include <linux/spinlock.h>
+#include <linux/kernel_stat.h>
+#include <hwregs/reg_map.h>
+#include <hwregs/reg_rdwr.h>
+#include <hwregs/intr_vect.h>
+#include <hwregs/intr_vect_defs.h>
+
+#define CPU_FIXED -1
+
+/* IRQ masks (refer to comment for crisv32_do_multiple) */
+#if TIMER0_INTR_VECT - FIRST_IRQ < 32
+#define TIMER_MASK (1 << (TIMER0_INTR_VECT - FIRST_IRQ))
+#undef TIMER_VECT1
+#else
+#define TIMER_MASK (1 << (TIMER0_INTR_VECT - FIRST_IRQ - 32))
+#define TIMER_VECT1
+#endif
+#ifdef CONFIG_ETRAX_KGDB
+#if defined(CONFIG_ETRAX_KGDB_PORT0)
+#define IGNOREMASK (1 << (SER0_INTR_VECT - FIRST_IRQ))
+#elif defined(CONFIG_ETRAX_KGDB_PORT1)
+#define IGNOREMASK (1 << (SER1_INTR_VECT - FIRST_IRQ))
+#elif defined(CONFIG_ETRAX_KGB_PORT2)
+#define IGNOREMASK (1 << (SER2_INTR_VECT - FIRST_IRQ))
+#elif defined(CONFIG_ETRAX_KGDB_PORT3)
+#define IGNOREMASK (1 << (SER3_INTR_VECT - FIRST_IRQ))
+#endif
+#endif
+
+DEFINE_SPINLOCK(irq_lock);
+
+struct cris_irq_allocation
+{
+  int cpu; /* The CPU to which the IRQ is currently allocated. */
+  cpumask_t mask; /* The CPUs to which the IRQ may be allocated. */
+};
+
+struct cris_irq_allocation irq_allocations[NR_REAL_IRQS] =
+  { [0 ... NR_REAL_IRQS - 1] = {0, CPU_MASK_ALL} };
+
+static unsigned long irq_regs[NR_CPUS] =
+{
+  regi_irq,
+};
+
+#if NR_REAL_IRQS > 32
+#define NBR_REGS 2
+#else
+#define NBR_REGS 1
+#endif
+
+unsigned long cpu_irq_counters[NR_CPUS];
+unsigned long irq_counters[NR_REAL_IRQS];
+
+/* From irq.c. */
+extern void weird_irq(void);
+
+/* From entry.S. */
+extern void system_call(void);
+extern void nmi_interrupt(void);
+extern void multiple_interrupt(void);
+extern void gdb_handle_exception(void);
+extern void i_mmu_refill(void);
+extern void i_mmu_invalid(void);
+extern void i_mmu_access(void);
+extern void i_mmu_execute(void);
+extern void d_mmu_refill(void);
+extern void d_mmu_invalid(void);
+extern void d_mmu_access(void);
+extern void d_mmu_write(void);
+
+/* From kgdb.c. */
+extern void kgdb_init(void);
+extern void breakpoint(void);
+
+/* From traps.c.  */
+extern void breakh_BUG(void);
+
+/*
+ * Build the IRQ handler stubs using macros from irq.h.
+ */
+#ifdef CONFIG_CRIS_MACH_ARTPEC3
+BUILD_TIMER_IRQ(0x31, 0)
+#else
+BUILD_IRQ(0x31)
+#endif
+BUILD_IRQ(0x32)
+BUILD_IRQ(0x33)
+BUILD_IRQ(0x34)
+BUILD_IRQ(0x35)
+BUILD_IRQ(0x36)
+BUILD_IRQ(0x37)
+BUILD_IRQ(0x38)
+BUILD_IRQ(0x39)
+BUILD_IRQ(0x3a)
+BUILD_IRQ(0x3b)
+BUILD_IRQ(0x3c)
+BUILD_IRQ(0x3d)
+BUILD_IRQ(0x3e)
+BUILD_IRQ(0x3f)
+BUILD_IRQ(0x40)
+BUILD_IRQ(0x41)
+BUILD_IRQ(0x42)
+BUILD_IRQ(0x43)
+BUILD_IRQ(0x44)
+BUILD_IRQ(0x45)
+BUILD_IRQ(0x46)
+BUILD_IRQ(0x47)
+BUILD_IRQ(0x48)
+BUILD_IRQ(0x49)
+BUILD_IRQ(0x4a)
+#ifdef CONFIG_ETRAXFS
+BUILD_TIMER_IRQ(0x4b, 0)
+#else
+BUILD_IRQ(0x4b)
+#endif
+BUILD_IRQ(0x4c)
+BUILD_IRQ(0x4d)
+BUILD_IRQ(0x4e)
+BUILD_IRQ(0x4f)
+BUILD_IRQ(0x50)
+#if MACH_IRQS > 32
+BUILD_IRQ(0x51)
+BUILD_IRQ(0x52)
+BUILD_IRQ(0x53)
+BUILD_IRQ(0x54)
+BUILD_IRQ(0x55)
+BUILD_IRQ(0x56)
+BUILD_IRQ(0x57)
+BUILD_IRQ(0x58)
+BUILD_IRQ(0x59)
+BUILD_IRQ(0x5a)
+BUILD_IRQ(0x5b)
+BUILD_IRQ(0x5c)
+BUILD_IRQ(0x5d)
+BUILD_IRQ(0x5e)
+BUILD_IRQ(0x5f)
+BUILD_IRQ(0x60)
+BUILD_IRQ(0x61)
+BUILD_IRQ(0x62)
+BUILD_IRQ(0x63)
+BUILD_IRQ(0x64)
+BUILD_IRQ(0x65)
+BUILD_IRQ(0x66)
+BUILD_IRQ(0x67)
+BUILD_IRQ(0x68)
+BUILD_IRQ(0x69)
+BUILD_IRQ(0x6a)
+BUILD_IRQ(0x6b)
+BUILD_IRQ(0x6c)
+BUILD_IRQ(0x6d)
+BUILD_IRQ(0x6e)
+BUILD_IRQ(0x6f)
+BUILD_IRQ(0x70)
+#endif
+
+/* Pointers to the low-level handlers. */
+static void (*interrupt[MACH_IRQS])(void) = {
+	IRQ0x31_interrupt, IRQ0x32_interrupt, IRQ0x33_interrupt,
+	IRQ0x34_interrupt, IRQ0x35_interrupt, IRQ0x36_interrupt,
+	IRQ0x37_interrupt, IRQ0x38_interrupt, IRQ0x39_interrupt,
+	IRQ0x3a_interrupt, IRQ0x3b_interrupt, IRQ0x3c_interrupt,
+	IRQ0x3d_interrupt, IRQ0x3e_interrupt, IRQ0x3f_interrupt,
+	IRQ0x40_interrupt, IRQ0x41_interrupt, IRQ0x42_interrupt,
+	IRQ0x43_interrupt, IRQ0x44_interrupt, IRQ0x45_interrupt,
+	IRQ0x46_interrupt, IRQ0x47_interrupt, IRQ0x48_interrupt,
+	IRQ0x49_interrupt, IRQ0x4a_interrupt, IRQ0x4b_interrupt,
+	IRQ0x4c_interrupt, IRQ0x4d_interrupt, IRQ0x4e_interrupt,
+	IRQ0x4f_interrupt, IRQ0x50_interrupt,
+#if MACH_IRQS > 32
+	IRQ0x51_interrupt, IRQ0x52_interrupt, IRQ0x53_interrupt,
+	IRQ0x54_interrupt, IRQ0x55_interrupt, IRQ0x56_interrupt,
+	IRQ0x57_interrupt, IRQ0x58_interrupt, IRQ0x59_interrupt,
+	IRQ0x5a_interrupt, IRQ0x5b_interrupt, IRQ0x5c_interrupt,
+	IRQ0x5d_interrupt, IRQ0x5e_interrupt, IRQ0x5f_interrupt,
+	IRQ0x60_interrupt, IRQ0x61_interrupt, IRQ0x62_interrupt,
+	IRQ0x63_interrupt, IRQ0x64_interrupt, IRQ0x65_interrupt,
+	IRQ0x66_interrupt, IRQ0x67_interrupt, IRQ0x68_interrupt,
+	IRQ0x69_interrupt, IRQ0x6a_interrupt, IRQ0x6b_interrupt,
+	IRQ0x6c_interrupt, IRQ0x6d_interrupt, IRQ0x6e_interrupt,
+	IRQ0x6f_interrupt, IRQ0x70_interrupt,
+#endif
+};
+
+void
+block_irq(int irq, int cpu)
+{
+	int intr_mask;
+        unsigned long flags;
+
+	spin_lock_irqsave(&irq_lock, flags);
+	/* Remember, 1 let thru, 0 block. */
+	if (irq - FIRST_IRQ < 32) {
+		intr_mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu],
+			rw_mask, 0);
+		intr_mask &= ~(1 << (irq - FIRST_IRQ));
+		REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask,
+			0, intr_mask);
+	} else {
+		intr_mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu],
+			rw_mask, 1);
+		intr_mask &= ~(1 << (irq - FIRST_IRQ - 32));
+		REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask,
+			1, intr_mask);
+	}
+        spin_unlock_irqrestore(&irq_lock, flags);
+}
+
+void
+unblock_irq(int irq, int cpu)
+{
+	int intr_mask;
+        unsigned long flags;
+
+        spin_lock_irqsave(&irq_lock, flags);
+	/* Remember, 1 let thru, 0 block. */
+	if (irq - FIRST_IRQ < 32) {
+		intr_mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu],
+			rw_mask, 0);
+		intr_mask |= (1 << (irq - FIRST_IRQ));
+		REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask,
+			0, intr_mask);
+	} else {
+		intr_mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu],
+			rw_mask, 1);
+		intr_mask |= (1 << (irq - FIRST_IRQ - 32));
+		REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask,
+			1, intr_mask);
+	}
+        spin_unlock_irqrestore(&irq_lock, flags);
+}
+
+/* Find out which CPU the irq should be allocated to. */
+static int irq_cpu(int irq)
+{
+	int cpu;
+        unsigned long flags;
+
+        spin_lock_irqsave(&irq_lock, flags);
+        cpu = irq_allocations[irq - FIRST_IRQ].cpu;
+
+	/* Fixed interrupts stay on the local CPU. */
+	if (cpu == CPU_FIXED)
+        {
+		spin_unlock_irqrestore(&irq_lock, flags);
+		return smp_processor_id();
+        }
+
+
+	/* Let the interrupt stay if possible */
+	if (cpumask_test_cpu(cpu, &irq_allocations[irq - FIRST_IRQ].mask))
+		goto out;
+
+	/* IRQ must be moved to another CPU. */
+	cpu = cpumask_first(&irq_allocations[irq - FIRST_IRQ].mask);
+	irq_allocations[irq - FIRST_IRQ].cpu = cpu;
+out:
+	spin_unlock_irqrestore(&irq_lock, flags);
+	return cpu;
+}
+
+void crisv32_mask_irq(int irq)
+{
+	int cpu;
+
+	for (cpu = 0; cpu < NR_CPUS; cpu++)
+		block_irq(irq, cpu);
+}
+
+void crisv32_unmask_irq(int irq)
+{
+	unblock_irq(irq, irq_cpu(irq));
+}
+
+
+static void enable_crisv32_irq(struct irq_data *data)
+{
+	crisv32_unmask_irq(data->irq);
+}
+
+static void disable_crisv32_irq(struct irq_data *data)
+{
+	crisv32_mask_irq(data->irq);
+}
+
+static int set_affinity_crisv32_irq(struct irq_data *data,
+				    const struct cpumask *dest, bool force)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&irq_lock, flags);
+	irq_allocations[data->irq - FIRST_IRQ].mask = *dest;
+	spin_unlock_irqrestore(&irq_lock, flags);
+	return 0;
+}
+
+static struct irq_chip crisv32_irq_type = {
+	.name			= "CRISv32",
+	.irq_shutdown		= disable_crisv32_irq,
+	.irq_enable		= enable_crisv32_irq,
+	.irq_disable		= disable_crisv32_irq,
+	.irq_set_affinity	= set_affinity_crisv32_irq,
+};
+
+void
+set_exception_vector(int n, irqvectptr addr)
+{
+	etrax_irv->v[n] = (irqvectptr) addr;
+}
+
+extern void do_IRQ(int irq, struct pt_regs * regs);
+
+void
+crisv32_do_IRQ(int irq, int block, struct pt_regs* regs)
+{
+	/* Interrupts that may not be moved to another CPU may
+	 * skip blocking. This is currently only valid for the
+	 * timer IRQ and the IPI and is used for the timer
+	 * interrupt to avoid watchdog starvation.
+	 */
+	if (!block) {
+		do_IRQ(irq, regs);
+		return;
+	}
+
+	block_irq(irq, smp_processor_id());
+	do_IRQ(irq, regs);
+
+	unblock_irq(irq, irq_cpu(irq));
+}
+
+/* If multiple interrupts occur simultaneously we get a multiple
+ * interrupt from the CPU and software has to sort out which
+ * interrupts that happened. There are two special cases here:
+ *
+ * 1. Timer interrupts may never be blocked because of the
+ *    watchdog (refer to comment in include/asr/arch/irq.h)
+ * 2. GDB serial port IRQs are unhandled here and will be handled
+ *    as a single IRQ when it strikes again because the GDB
+ *    stubb wants to save the registers in its own fashion.
+ */
+void
+crisv32_do_multiple(struct pt_regs* regs)
+{
+	int cpu;
+	int mask;
+	int masked[NBR_REGS];
+	int bit;
+	int i;
+
+	cpu = smp_processor_id();
+
+	/* An extra irq_enter here to prevent softIRQs to run after
+         * each do_IRQ. This will decrease the interrupt latency.
+	 */
+	irq_enter();
+
+	for (i = 0; i < NBR_REGS; i++) {
+		/* Get which IRQs that happened. */
+		masked[i] = REG_RD_INT_VECT(intr_vect, irq_regs[cpu],
+			r_masked_vect, i);
+
+		/* Calculate new IRQ mask with these IRQs disabled. */
+		mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, i);
+		mask &= ~masked[i];
+
+	/* Timer IRQ is never masked */
+#ifdef TIMER_VECT1
+		if ((i == 1) && (masked[0] & TIMER_MASK))
+			mask |= TIMER_MASK;
+#else
+		if ((i == 0) && (masked[0] & TIMER_MASK))
+			mask |= TIMER_MASK;
+#endif
+		/* Block all the IRQs */
+		REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, i, mask);
+
+	/* Check for timer IRQ and handle it special. */
+#ifdef TIMER_VECT1
+		if ((i == 1) && (masked[i] & TIMER_MASK)) {
+			masked[i] &= ~TIMER_MASK;
+			do_IRQ(TIMER0_INTR_VECT, regs);
+		}
+#else
+		if ((i == 0) && (masked[i] & TIMER_MASK)) {
+			 masked[i] &= ~TIMER_MASK;
+			 do_IRQ(TIMER0_INTR_VECT, regs);
+		}
+#endif
+	}
+
+#ifdef IGNORE_MASK
+	/* Remove IRQs that can't be handled as multiple. */
+	masked[0] &= ~IGNORE_MASK;
+#endif
+
+	/* Handle the rest of the IRQs. */
+	for (i = 0; i < NBR_REGS; i++) {
+		for (bit = 0; bit < 32; bit++) {
+			if (masked[i] & (1 << bit))
+				do_IRQ(bit + FIRST_IRQ + i*32, regs);
+		}
+	}
+
+	/* Unblock all the IRQs. */
+	for (i = 0; i < NBR_REGS; i++) {
+		mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, i);
+		mask |= masked[i];
+		REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, i, mask);
+	}
+
+	/* This irq_exit() will trigger the soft IRQs. */
+	irq_exit();
+}
+
+static int crisv32_irq_map(struct irq_domain *h, unsigned int virq,
+			   irq_hw_number_t hw_irq_num)
+{
+	irq_set_chip_and_handler(virq, &crisv32_irq_type, handle_simple_irq);
+
+	return 0;
+}
+
+static struct irq_domain_ops crisv32_irq_ops = {
+	.map	= crisv32_irq_map,
+	.xlate	= irq_domain_xlate_onecell,
+};
+
+/*
+ * This is called by start_kernel. It fixes the IRQ masks and setup the
+ * interrupt vector table to point to bad_interrupt pointers.
+ */
+void __init
+init_IRQ(void)
+{
+	int i;
+	int j;
+	reg_intr_vect_rw_mask vect_mask = {0};
+	struct device_node *np;
+	struct irq_domain *domain;
+
+	/* Clear all interrupts masks. */
+	for (i = 0; i < NBR_REGS; i++)
+		REG_WR_VECT(intr_vect, regi_irq, rw_mask, i, vect_mask);
+
+	for (i = 0; i < 256; i++)
+		etrax_irv->v[i] = weird_irq;
+
+	np = of_find_compatible_node(NULL, NULL, "axis,crisv32-intc");
+	domain = irq_domain_add_legacy(np, NR_IRQS - FIRST_IRQ,
+				       FIRST_IRQ, FIRST_IRQ,
+				       &crisv32_irq_ops, NULL);
+	BUG_ON(!domain);
+	irq_set_default_host(domain);
+	of_node_put(np);
+
+	for (i = FIRST_IRQ, j = 0; j < NR_IRQS; i++, j++) {
+		set_exception_vector(i, interrupt[j]);
+	}
+
+	/* Mark Timer and IPI IRQs as CPU local */
+	irq_allocations[TIMER0_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED;
+	irq_set_status_flags(TIMER0_INTR_VECT, IRQ_PER_CPU);
+	irq_allocations[IPI_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED;
+	irq_set_status_flags(IPI_INTR_VECT, IRQ_PER_CPU);
+
+	set_exception_vector(0x00, nmi_interrupt);
+	set_exception_vector(0x30, multiple_interrupt);
+
+	/* Set up handler for various MMU bus faults. */
+	set_exception_vector(0x04, i_mmu_refill);
+	set_exception_vector(0x05, i_mmu_invalid);
+	set_exception_vector(0x06, i_mmu_access);
+	set_exception_vector(0x07, i_mmu_execute);
+	set_exception_vector(0x08, d_mmu_refill);
+	set_exception_vector(0x09, d_mmu_invalid);
+	set_exception_vector(0x0a, d_mmu_access);
+	set_exception_vector(0x0b, d_mmu_write);
+
+#ifdef CONFIG_BUG
+	/* Break 14 handler, used to implement cheap BUG().  */
+	set_exception_vector(0x1e, breakh_BUG);
+#endif
+
+	/* The system-call trap is reached by "break 13". */
+	set_exception_vector(0x1d, system_call);
+
+	/* Exception handlers for debugging, both user-mode and kernel-mode. */
+
+	/* Break 8. */
+	set_exception_vector(0x18, gdb_handle_exception);
+	/* Hardware single step. */
+	set_exception_vector(0x3, gdb_handle_exception);
+	/* Hardware breakpoint. */
+	set_exception_vector(0xc, gdb_handle_exception);
+
+#ifdef CONFIG_ETRAX_KGDB
+	kgdb_init();
+	/* Everything is set up; now trap the kernel. */
+	breakpoint();
+#endif
+}
+