Initial import

1 files changed, 518 insertions, 0 deletions

diff --git a/arch/sparc/kernel/sun4d_irq.c b/arch/sparc/kernel/sun4d_irq.c
new file mode 100644
index 000000000..a1bb2675b
--- /dev/null
+++ b/arch/sparc/kernel/sun4d_irq.c
@@ -0,0 +1,518 @@
+/*
+ * SS1000/SC2000 interrupt handling.
+ *
+ *  Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ *  Heavily based on arch/sparc/kernel/irq.c.
+ */
+
+#include <linux/kernel_stat.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+
+#include <asm/timer.h>
+#include <asm/traps.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/sbi.h>
+#include <asm/cacheflush.h>
+#include <asm/setup.h>
+#include <asm/oplib.h>
+
+#include "kernel.h"
+#include "irq.h"
+
+/* Sun4d interrupts fall roughly into two categories.  SBUS and
+ * cpu local.  CPU local interrupts cover the timer interrupts
+ * and whatnot, and we encode those as normal PILs between
+ * 0 and 15.
+ * SBUS interrupts are encodes as a combination of board, level and slot.
+ */
+
+struct sun4d_handler_data {
+	unsigned int cpuid;    /* target cpu */
+	unsigned int real_irq; /* interrupt level */
+};
+
+
+static unsigned int sun4d_encode_irq(int board, int lvl, int slot)
+{
+	return (board + 1) << 5 | (lvl << 2) | slot;
+}
+
+struct sun4d_timer_regs {
+	u32	l10_timer_limit;
+	u32	l10_cur_countx;
+	u32	l10_limit_noclear;
+	u32	ctrl;
+	u32	l10_cur_count;
+};
+
+static struct sun4d_timer_regs __iomem *sun4d_timers;
+
+#define SUN4D_TIMER_IRQ        10
+
+/* Specify which cpu handle interrupts from which board.
+ * Index is board - value is cpu.
+ */
+static unsigned char board_to_cpu[32];
+
+static int pil_to_sbus[] = {
+	0,
+	0,
+	1,
+	2,
+	0,
+	3,
+	0,
+	4,
+	0,
+	5,
+	0,
+	6,
+	0,
+	7,
+	0,
+	0,
+};
+
+/* Exported for sun4d_smp.c */
+DEFINE_SPINLOCK(sun4d_imsk_lock);
+
+/* SBUS interrupts are encoded integers including the board number
+ * (plus one), the SBUS level, and the SBUS slot number.  Sun4D
+ * IRQ dispatch is done by:
+ *
+ * 1) Reading the BW local interrupt table in order to get the bus
+ *    interrupt mask.
+ *
+ *    This table is indexed by SBUS interrupt level which can be
+ *    derived from the PIL we got interrupted on.
+ *
+ * 2) For each bus showing interrupt pending from #1, read the
+ *    SBI interrupt state register.  This will indicate which slots
+ *    have interrupts pending for that SBUS interrupt level.
+ *
+ * 3) Call the genreric IRQ support.
+ */
+static void sun4d_sbus_handler_irq(int sbusl)
+{
+	unsigned int bus_mask;
+	unsigned int sbino, slot;
+	unsigned int sbil;
+
+	bus_mask = bw_get_intr_mask(sbusl) & 0x3ffff;
+	bw_clear_intr_mask(sbusl, bus_mask);
+
+	sbil = (sbusl << 2);
+	/* Loop for each pending SBI */
+	for (sbino = 0; bus_mask; sbino++, bus_mask >>= 1) {
+		unsigned int idx, mask;
+
+		if (!(bus_mask & 1))
+			continue;
+		/* XXX This seems to ACK the irq twice.  acquire_sbi()
+		 * XXX uses swap, therefore this writes 0xf << sbil,
+		 * XXX then later release_sbi() will write the individual
+		 * XXX bits which were set again.
+		 */
+		mask = acquire_sbi(SBI2DEVID(sbino), 0xf << sbil);
+		mask &= (0xf << sbil);
+
+		/* Loop for each pending SBI slot */
+		slot = (1 << sbil);
+		for (idx = 0; mask != 0; idx++, slot <<= 1) {
+			unsigned int pil;
+			struct irq_bucket *p;
+
+			if (!(mask & slot))
+				continue;
+
+			mask &= ~slot;
+			pil = sun4d_encode_irq(sbino, sbusl, idx);
+
+			p = irq_map[pil];
+			while (p) {
+				struct irq_bucket *next;
+
+				next = p->next;
+				generic_handle_irq(p->irq);
+				p = next;
+			}
+			release_sbi(SBI2DEVID(sbino), slot);
+		}
+	}
+}
+
+void sun4d_handler_irq(unsigned int pil, struct pt_regs *regs)
+{
+	struct pt_regs *old_regs;
+	/* SBUS IRQ level (1 - 7) */
+	int sbusl = pil_to_sbus[pil];
+
+	/* FIXME: Is this necessary?? */
+	cc_get_ipen();
+
+	cc_set_iclr(1 << pil);
+
+#ifdef CONFIG_SMP
+	/*
+	 * Check IPI data structures after IRQ has been cleared. Hard and Soft
+	 * IRQ can happen at the same time, so both cases are always handled.
+	 */
+	if (pil == SUN4D_IPI_IRQ)
+		sun4d_ipi_interrupt();
+#endif
+
+	old_regs = set_irq_regs(regs);
+	irq_enter();
+	if (sbusl == 0) {
+		/* cpu interrupt */
+		struct irq_bucket *p;
+
+		p = irq_map[pil];
+		while (p) {
+			struct irq_bucket *next;
+
+			next = p->next;
+			generic_handle_irq(p->irq);
+			p = next;
+		}
+	} else {
+		/* SBUS interrupt */
+		sun4d_sbus_handler_irq(sbusl);
+	}
+	irq_exit();
+	set_irq_regs(old_regs);
+}
+
+
+static void sun4d_mask_irq(struct irq_data *data)
+{
+	struct sun4d_handler_data *handler_data = data->handler_data;
+	unsigned int real_irq;
+#ifdef CONFIG_SMP
+	int cpuid = handler_data->cpuid;
+	unsigned long flags;
+#endif
+	real_irq = handler_data->real_irq;
+#ifdef CONFIG_SMP
+	spin_lock_irqsave(&sun4d_imsk_lock, flags);
+	cc_set_imsk_other(cpuid, cc_get_imsk_other(cpuid) | (1 << real_irq));
+	spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
+#else
+	cc_set_imsk(cc_get_imsk() | (1 << real_irq));
+#endif
+}
+
+static void sun4d_unmask_irq(struct irq_data *data)
+{
+	struct sun4d_handler_data *handler_data = data->handler_data;
+	unsigned int real_irq;
+#ifdef CONFIG_SMP
+	int cpuid = handler_data->cpuid;
+	unsigned long flags;
+#endif
+	real_irq = handler_data->real_irq;
+
+#ifdef CONFIG_SMP
+	spin_lock_irqsave(&sun4d_imsk_lock, flags);
+	cc_set_imsk_other(cpuid, cc_get_imsk_other(cpuid) & ~(1 << real_irq));
+	spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
+#else
+	cc_set_imsk(cc_get_imsk() & ~(1 << real_irq));
+#endif
+}
+
+static unsigned int sun4d_startup_irq(struct irq_data *data)
+{
+	irq_link(data->irq);
+	sun4d_unmask_irq(data);
+	return 0;
+}
+
+static void sun4d_shutdown_irq(struct irq_data *data)
+{
+	sun4d_mask_irq(data);
+	irq_unlink(data->irq);
+}
+
+static struct irq_chip sun4d_irq = {
+	.name		= "sun4d",
+	.irq_startup	= sun4d_startup_irq,
+	.irq_shutdown	= sun4d_shutdown_irq,
+	.irq_unmask	= sun4d_unmask_irq,
+	.irq_mask	= sun4d_mask_irq,
+};
+
+#ifdef CONFIG_SMP
+/* Setup IRQ distribution scheme. */
+void __init sun4d_distribute_irqs(void)
+{
+	struct device_node *dp;
+
+	int cpuid = cpu_logical_map(1);
+
+	if (cpuid == -1)
+		cpuid = cpu_logical_map(0);
+	for_each_node_by_name(dp, "sbi") {
+		int devid = of_getintprop_default(dp, "device-id", 0);
+		int board = of_getintprop_default(dp, "board#", 0);
+		board_to_cpu[board] = cpuid;
+		set_sbi_tid(devid, cpuid << 3);
+	}
+	printk(KERN_ERR "All sbus IRQs directed to CPU%d\n", cpuid);
+}
+#endif
+
+static void sun4d_clear_clock_irq(void)
+{
+	sbus_readl(&sun4d_timers->l10_timer_limit);
+}
+
+static void sun4d_load_profile_irq(int cpu, unsigned int limit)
+{
+	unsigned int value = limit ? timer_value(limit) : 0;
+	bw_set_prof_limit(cpu, value);
+}
+
+static void __init sun4d_load_profile_irqs(void)
+{
+	int cpu = 0, mid;
+
+	while (!cpu_find_by_instance(cpu, NULL, &mid)) {
+		sun4d_load_profile_irq(mid >> 3, 0);
+		cpu++;
+	}
+}
+
+static unsigned int _sun4d_build_device_irq(unsigned int real_irq,
+                                            unsigned int pil,
+                                            unsigned int board)
+{
+	struct sun4d_handler_data *handler_data;
+	unsigned int irq;
+
+	irq = irq_alloc(real_irq, pil);
+	if (irq == 0) {
+		prom_printf("IRQ: allocate for %d %d %d failed\n",
+			real_irq, pil, board);
+		goto err_out;
+	}
+
+	handler_data = irq_get_handler_data(irq);
+	if (unlikely(handler_data))
+		goto err_out;
+
+	handler_data = kzalloc(sizeof(struct sun4d_handler_data), GFP_ATOMIC);
+	if (unlikely(!handler_data)) {
+		prom_printf("IRQ: kzalloc(sun4d_handler_data) failed.\n");
+		prom_halt();
+	}
+	handler_data->cpuid    = board_to_cpu[board];
+	handler_data->real_irq = real_irq;
+	irq_set_chip_and_handler_name(irq, &sun4d_irq,
+	                              handle_level_irq, "level");
+	irq_set_handler_data(irq, handler_data);
+
+err_out:
+	return irq;
+}
+
+
+
+static unsigned int sun4d_build_device_irq(struct platform_device *op,
+                                           unsigned int real_irq)
+{
+	struct device_node *dp = op->dev.of_node;
+	struct device_node *board_parent, *bus = dp->parent;
+	char *bus_connection;
+	const struct linux_prom_registers *regs;
+	unsigned int pil;
+	unsigned int irq;
+	int board, slot;
+	int sbusl;
+
+	irq = real_irq;
+	while (bus) {
+		if (!strcmp(bus->name, "sbi")) {
+			bus_connection = "io-unit";
+			break;
+		}
+
+		if (!strcmp(bus->name, "bootbus")) {
+			bus_connection = "cpu-unit";
+			break;
+		}
+
+		bus = bus->parent;
+	}
+	if (!bus)
+		goto err_out;
+
+	regs = of_get_property(dp, "reg", NULL);
+	if (!regs)
+		goto err_out;
+
+	slot = regs->which_io;
+
+	/*
+	 * If Bus nodes parent is not io-unit/cpu-unit or the io-unit/cpu-unit
+	 * lacks a "board#" property, something is very wrong.
+	 */
+	if (!bus->parent || strcmp(bus->parent->name, bus_connection)) {
+		printk(KERN_ERR "%s: Error, parent is not %s.\n",
+			bus->full_name, bus_connection);
+		goto err_out;
+	}
+	board_parent = bus->parent;
+	board = of_getintprop_default(board_parent, "board#", -1);
+	if (board == -1) {
+		printk(KERN_ERR "%s: Error, lacks board# property.\n",
+			board_parent->full_name);
+		goto err_out;
+	}
+
+	sbusl = pil_to_sbus[real_irq];
+	if (sbusl)
+		pil = sun4d_encode_irq(board, sbusl, slot);
+	else
+		pil = real_irq;
+
+	irq = _sun4d_build_device_irq(real_irq, pil, board);
+err_out:
+	return irq;
+}
+
+static unsigned int sun4d_build_timer_irq(unsigned int board,
+                                          unsigned int real_irq)
+{
+	return _sun4d_build_device_irq(real_irq, real_irq, board);
+}
+
+
+static void __init sun4d_fixup_trap_table(void)
+{
+#ifdef CONFIG_SMP
+	unsigned long flags;
+	struct tt_entry *trap_table = &sparc_ttable[SP_TRAP_IRQ1 + (14 - 1)];
+
+	/* Adjust so that we jump directly to smp4d_ticker */
+	lvl14_save[2] += smp4d_ticker - real_irq_entry;
+
+	/* For SMP we use the level 14 ticker, however the bootup code
+	 * has copied the firmware's level 14 vector into the boot cpu's
+	 * trap table, we must fix this now or we get squashed.
+	 */
+	local_irq_save(flags);
+	patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
+	trap_table->inst_one = lvl14_save[0];
+	trap_table->inst_two = lvl14_save[1];
+	trap_table->inst_three = lvl14_save[2];
+	trap_table->inst_four = lvl14_save[3];
+	local_ops->cache_all();
+	local_irq_restore(flags);
+#endif
+}
+
+static void __init sun4d_init_timers(void)
+{
+	struct device_node *dp;
+	struct resource res;
+	unsigned int irq;
+	const u32 *reg;
+	int err;
+	int board;
+
+	dp = of_find_node_by_name(NULL, "cpu-unit");
+	if (!dp) {
+		prom_printf("sun4d_init_timers: Unable to find cpu-unit\n");
+		prom_halt();
+	}
+
+	/* Which cpu-unit we use is arbitrary, we can view the bootbus timer
+	 * registers via any cpu's mapping.  The first 'reg' property is the
+	 * bootbus.
+	 */
+	reg = of_get_property(dp, "reg", NULL);
+	if (!reg) {
+		prom_printf("sun4d_init_timers: No reg property\n");
+		prom_halt();
+	}
+
+	board = of_getintprop_default(dp, "board#", -1);
+	if (board == -1) {
+		prom_printf("sun4d_init_timers: No board# property on cpu-unit\n");
+		prom_halt();
+	}
+
+	of_node_put(dp);
+
+	res.start = reg[1];
+	res.end = reg[2] - 1;
+	res.flags = reg[0] & 0xff;
+	sun4d_timers = of_ioremap(&res, BW_TIMER_LIMIT,
+				  sizeof(struct sun4d_timer_regs), "user timer");
+	if (!sun4d_timers) {
+		prom_printf("sun4d_init_timers: Can't map timer regs\n");
+		prom_halt();
+	}
+
+#ifdef CONFIG_SMP
+	sparc_config.cs_period = SBUS_CLOCK_RATE * 2;  /* 2 seconds */
+#else
+	sparc_config.cs_period = SBUS_CLOCK_RATE / HZ; /* 1/HZ sec  */
+	sparc_config.features |= FEAT_L10_CLOCKEVENT;
+#endif
+	sparc_config.features |= FEAT_L10_CLOCKSOURCE;
+	sbus_writel(timer_value(sparc_config.cs_period),
+		    &sun4d_timers->l10_timer_limit);
+
+	master_l10_counter = &sun4d_timers->l10_cur_count;
+
+	irq = sun4d_build_timer_irq(board, SUN4D_TIMER_IRQ);
+	err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
+	if (err) {
+		prom_printf("sun4d_init_timers: request_irq() failed with %d\n",
+		             err);
+		prom_halt();
+	}
+	sun4d_load_profile_irqs();
+	sun4d_fixup_trap_table();
+}
+
+void __init sun4d_init_sbi_irq(void)
+{
+	struct device_node *dp;
+	int target_cpu;
+
+	target_cpu = boot_cpu_id;
+	for_each_node_by_name(dp, "sbi") {
+		int devid = of_getintprop_default(dp, "device-id", 0);
+		int board = of_getintprop_default(dp, "board#", 0);
+		unsigned int mask;
+
+		set_sbi_tid(devid, target_cpu << 3);
+		board_to_cpu[board] = target_cpu;
+
+		/* Get rid of pending irqs from PROM */
+		mask = acquire_sbi(devid, 0xffffffff);
+		if (mask) {
+			printk(KERN_ERR "Clearing pending IRQs %08x on SBI %d\n",
+			       mask, board);
+			release_sbi(devid, mask);
+		}
+	}
+}
+
+void __init sun4d_init_IRQ(void)
+{
+	local_irq_disable();
+
+	sparc_config.init_timers      = sun4d_init_timers;
+	sparc_config.build_device_irq = sun4d_build_device_irq;
+	sparc_config.clock_rate       = SBUS_CLOCK_RATE;
+	sparc_config.clear_clock_irq  = sun4d_clear_clock_irq;
+	sparc_config.load_profile_irq = sun4d_load_profile_irq;
+
+	/* Cannot enable interrupts until OBP ticker is disabled. */
+}