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-rw-r--r--arch/sparc/kernel/sun4d_irq.c519
1 files changed, 519 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..9a137c70e
--- /dev/null
+++ b/arch/sparc/kernel/sun4d_irq.c
@@ -0,0 +1,519 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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 = irq_data_get_irq_handler_data(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 = irq_data_get_irq_handler_data(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 (of_node_name_eq(bus, "sbi")) {
+ bus_connection = "io-unit";
+ break;
+ }
+
+ if (of_node_name_eq(bus, "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 (!of_node_name_eq(bus->parent, bus_connection)) {
+ printk(KERN_ERR "%pOF: Error, parent is not %s.\n",
+ bus, bus_connection);
+ goto err_out;
+ }
+ board_parent = bus->parent;
+ board = of_getintprop_default(board_parent, "board#", -1);
+ if (board == -1) {
+ printk(KERN_ERR "%pOF: Error, lacks board# property.\n",
+ board_parent);
+ 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. */
+}
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