1 files changed, 509 insertions, 0 deletions
diff --git a/arch/sparc/kernel/leon_kernel.c b/arch/sparc/kernel/leon_kernel.c
new file mode 100644
index 0000000000..4c61da491f
--- /dev/null
+++ b/arch/sparc/kernel/leon_kernel.c
@@ -0,0 +1,509 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
+ * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/interrupt.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+
+#include <asm/oplib.h>
+#include <asm/timer.h>
+#include <asm/prom.h>
+#include <asm/leon.h>
+#include <asm/leon_amba.h>
+#include <asm/traps.h>
+#include <asm/cacheflush.h>
+#include <asm/smp.h>
+#include <asm/setup.h>
+
+#include "kernel.h"
+#include "prom.h"
+#include "irq.h"
+
+struct leon3_irqctrl_regs_map *leon3_irqctrl_regs; /* interrupt controller base address */
+struct leon3_gptimer_regs_map *leon3_gptimer_regs; /* timer controller base address */
+
+int leondebug_irq_disable;
+int leon_debug_irqout;
+static volatile u32 dummy_master_l10_counter;
+unsigned long amba_system_id;
+static DEFINE_SPINLOCK(leon_irq_lock);
+
+static unsigned long leon3_gptimer_idx; /* Timer Index (0..6) within Timer Core */
+static unsigned long leon3_gptimer_ackmask; /* For clearing pending bit */
+unsigned long leon3_gptimer_irq; /* interrupt controller irq number */
+unsigned int sparc_leon_eirq;
+#define LEON_IMASK(cpu) (&leon3_irqctrl_regs->mask[cpu])
+#define LEON_IACK (&leon3_irqctrl_regs->iclear)
+#define LEON_DO_ACK_HW 1
+
+/* Return the last ACKed IRQ by the Extended IRQ controller. It has already
+ * been (automatically) ACKed when the CPU takes the trap.
+ */
+static inline unsigned int leon_eirq_get(int cpu)
+{
+	return LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->intid[cpu]) & 0x1f;
+}
+
+/* Handle one or multiple IRQs from the extended interrupt controller */
+static void leon_handle_ext_irq(struct irq_desc *desc)
+{
+	unsigned int eirq;
+	struct irq_bucket *p;
+	int cpu = sparc_leon3_cpuid();
+
+	eirq = leon_eirq_get(cpu);
+	p = irq_map[eirq];
+	if ((eirq & 0x10) && p && p->irq) /* bit4 tells if IRQ happened */
+		generic_handle_irq(p->irq);
+}
+
+/* The extended IRQ controller has been found, this function registers it */
+static void leon_eirq_setup(unsigned int eirq)
+{
+	unsigned long mask, oldmask;
+	unsigned int veirq;
+
+	if (eirq < 1 || eirq > 0xf) {
+		printk(KERN_ERR "LEON EXT IRQ NUMBER BAD: %d\n", eirq);
+		return;
+	}
+
+	veirq = leon_build_device_irq(eirq, leon_handle_ext_irq, "extirq", 0);
+
+	/*
+	 * Unmask the Extended IRQ, the IRQs routed through the Ext-IRQ
+	 * controller have a mask-bit of their own, so this is safe.
+	 */
+	irq_link(veirq);
+	mask = 1 << eirq;
+	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(boot_cpu_id));
+	LEON3_BYPASS_STORE_PA(LEON_IMASK(boot_cpu_id), (oldmask | mask));
+	sparc_leon_eirq = eirq;
+}
+
+unsigned long leon_get_irqmask(unsigned int irq)
+{
+	unsigned long mask;
+
+	if (!irq || ((irq > 0xf) && !sparc_leon_eirq)
+	    || ((irq > 0x1f) && sparc_leon_eirq)) {
+		printk(KERN_ERR
+		       "leon_get_irqmask: false irq number: %d\n", irq);
+		mask = 0;
+	} else {
+		mask = LEON_HARD_INT(irq);
+	}
+	return mask;
+}
+
+#ifdef CONFIG_SMP
+static int irq_choose_cpu(const struct cpumask *affinity)
+{
+	cpumask_t mask;
+
+	cpumask_and(&mask, cpu_online_mask, affinity);
+	if (cpumask_equal(&mask, cpu_online_mask) || cpumask_empty(&mask))
+		return boot_cpu_id;
+	else
+		return cpumask_first(&mask);
+}
+#else
+#define irq_choose_cpu(affinity) boot_cpu_id
+#endif
+
+static int leon_set_affinity(struct irq_data *data, const struct cpumask *dest,
+			     bool force)
+{
+	unsigned long mask, oldmask, flags;
+	int oldcpu, newcpu;
+
+	mask = (unsigned long)data->chip_data;
+	oldcpu = irq_choose_cpu(irq_data_get_affinity_mask(data));
+	newcpu = irq_choose_cpu(dest);
+
+	if (oldcpu == newcpu)
+		goto out;
+
+	/* unmask on old CPU first before enabling on the selected CPU */
+	spin_lock_irqsave(&leon_irq_lock, flags);
+	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(oldcpu));
+	LEON3_BYPASS_STORE_PA(LEON_IMASK(oldcpu), (oldmask & ~mask));
+	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(newcpu));
+	LEON3_BYPASS_STORE_PA(LEON_IMASK(newcpu), (oldmask | mask));
+	spin_unlock_irqrestore(&leon_irq_lock, flags);
+out:
+	return IRQ_SET_MASK_OK;
+}
+
+static void leon_unmask_irq(struct irq_data *data)
+{
+	unsigned long mask, oldmask, flags;
+	int cpu;
+
+	mask = (unsigned long)data->chip_data;
+	cpu = irq_choose_cpu(irq_data_get_affinity_mask(data));
+	spin_lock_irqsave(&leon_irq_lock, flags);
+	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
+	LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask | mask));
+	spin_unlock_irqrestore(&leon_irq_lock, flags);
+}
+
+static void leon_mask_irq(struct irq_data *data)
+{
+	unsigned long mask, oldmask, flags;
+	int cpu;
+
+	mask = (unsigned long)data->chip_data;
+	cpu = irq_choose_cpu(irq_data_get_affinity_mask(data));
+	spin_lock_irqsave(&leon_irq_lock, flags);
+	oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
+	LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask & ~mask));
+	spin_unlock_irqrestore(&leon_irq_lock, flags);
+}
+
+static unsigned int leon_startup_irq(struct irq_data *data)
+{
+	irq_link(data->irq);
+	leon_unmask_irq(data);
+	return 0;
+}
+
+static void leon_shutdown_irq(struct irq_data *data)
+{
+	leon_mask_irq(data);
+	irq_unlink(data->irq);
+}
+
+/* Used by external level sensitive IRQ handlers on the LEON: ACK IRQ ctrl */
+static void leon_eoi_irq(struct irq_data *data)
+{
+	unsigned long mask = (unsigned long)data->chip_data;
+
+	if (mask & LEON_DO_ACK_HW)
+		LEON3_BYPASS_STORE_PA(LEON_IACK, mask & ~LEON_DO_ACK_HW);
+}
+
+static struct irq_chip leon_irq = {
+	.name			= "leon",
+	.irq_startup		= leon_startup_irq,
+	.irq_shutdown		= leon_shutdown_irq,
+	.irq_mask		= leon_mask_irq,
+	.irq_unmask		= leon_unmask_irq,
+	.irq_eoi		= leon_eoi_irq,
+	.irq_set_affinity	= leon_set_affinity,
+};
+
+/*
+ * Build a LEON IRQ for the edge triggered LEON IRQ controller:
+ *  Edge (normal) IRQ           - handle_simple_irq, ack=DON'T-CARE, never ack
+ *  Level IRQ (PCI|Level-GPIO)  - handle_fasteoi_irq, ack=1, ack after ISR
+ *  Per-CPU Edge                - handle_percpu_irq, ack=0
+ */
+unsigned int leon_build_device_irq(unsigned int real_irq,
+				    irq_flow_handler_t flow_handler,
+				    const char *name, int do_ack)
+{
+	unsigned int irq;
+	unsigned long mask;
+	struct irq_desc *desc;
+
+	irq = 0;
+	mask = leon_get_irqmask(real_irq);
+	if (mask == 0)
+		goto out;
+
+	irq = irq_alloc(real_irq, real_irq);
+	if (irq == 0)
+		goto out;
+
+	if (do_ack)
+		mask |= LEON_DO_ACK_HW;
+
+	desc = irq_to_desc(irq);
+	if (!desc || !desc->handle_irq || desc->handle_irq == handle_bad_irq) {
+		irq_set_chip_and_handler_name(irq, &leon_irq,
+					      flow_handler, name);
+		irq_set_chip_data(irq, (void *)mask);
+	}
+
+out:
+	return irq;
+}
+
+static unsigned int _leon_build_device_irq(struct platform_device *op,
+					   unsigned int real_irq)
+{
+	return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
+}
+
+void leon_update_virq_handling(unsigned int virq,
+			      irq_flow_handler_t flow_handler,
+			      const char *name, int do_ack)
+{
+	unsigned long mask = (unsigned long)irq_get_chip_data(virq);
+
+	mask &= ~LEON_DO_ACK_HW;
+	if (do_ack)
+		mask |= LEON_DO_ACK_HW;
+
+	irq_set_chip_and_handler_name(virq, &leon_irq,
+				      flow_handler, name);
+	irq_set_chip_data(virq, (void *)mask);
+}
+
+static u32 leon_cycles_offset(void)
+{
+	u32 rld, val, ctrl, off;
+
+	rld = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld);
+	val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
+	ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
+	if (LEON3_GPTIMER_CTRL_ISPENDING(ctrl)) {
+		val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
+		off = 2 * rld - val;
+	} else {
+		off = rld - val;
+	}
+
+	return off;
+}
+
+#ifdef CONFIG_SMP
+
+/* smp clockevent irq */
+static irqreturn_t leon_percpu_timer_ce_interrupt(int irq, void *unused)
+{
+	struct clock_event_device *ce;
+	int cpu = smp_processor_id();
+
+	leon_clear_profile_irq(cpu);
+
+	if (cpu == boot_cpu_id)
+		timer_interrupt(irq, NULL);
+
+	ce = &per_cpu(sparc32_clockevent, cpu);
+
+	irq_enter();
+	if (ce->event_handler)
+		ce->event_handler(ce);
+	irq_exit();
+
+	return IRQ_HANDLED;
+}
+
+#endif /* CONFIG_SMP */
+
+void __init leon_init_timers(void)
+{
+	int irq, eirq;
+	struct device_node *rootnp, *np, *nnp;
+	struct property *pp;
+	int len;
+	int icsel;
+	int ampopts;
+	int err;
+	u32 config;
+	u32 ctrl;
+
+	sparc_config.get_cycles_offset = leon_cycles_offset;
+	sparc_config.cs_period = 1000000 / HZ;
+	sparc_config.features |= FEAT_L10_CLOCKSOURCE;
+
+#ifndef CONFIG_SMP
+	sparc_config.features |= FEAT_L10_CLOCKEVENT;
+#endif
+
+	leondebug_irq_disable = 0;
+	leon_debug_irqout = 0;
+	master_l10_counter = (u32 __iomem *)&dummy_master_l10_counter;
+	dummy_master_l10_counter = 0;
+
+	rootnp = of_find_node_by_path("/ambapp0");
+	if (!rootnp)
+		goto bad;
+
+	/* Find System ID: GRLIB build ID and optional CHIP ID */
+	pp = of_find_property(rootnp, "systemid", &len);
+	if (pp)
+		amba_system_id = *(unsigned long *)pp->value;
+
+	/* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
+	np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
+	if (!np) {
+		np = of_find_node_by_name(rootnp, "01_00d");
+		if (!np)
+			goto bad;
+	}
+	pp = of_find_property(np, "reg", &len);
+	if (!pp)
+		goto bad;
+	leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
+
+	/* Find GPTIMER Timer Registers base address otherwise bail out. */
+	nnp = rootnp;
+
+retry:
+	np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
+	if (!np) {
+		np = of_find_node_by_name(nnp, "01_011");
+		if (!np)
+			goto bad;
+	}
+
+	ampopts = 0;
+	pp = of_find_property(np, "ampopts", &len);
+	if (pp) {
+		ampopts = *(int *)pp->value;
+		if (ampopts == 0) {
+			/* Skip this instance, resource already
+			 * allocated by other OS */
+			nnp = np;
+			goto retry;
+		}
+	}
+
+	/* Select Timer-Instance on Timer Core. Default is zero */
+	leon3_gptimer_idx = ampopts & 0x7;
+
+	pp = of_find_property(np, "reg", &len);
+	if (pp)
+		leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
+					pp->value;
+	pp = of_find_property(np, "interrupts", &len);
+	if (pp)
+		leon3_gptimer_irq = *(unsigned int *)pp->value;
+
+	if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
+		goto bad;
+
+	ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
+	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
+			      ctrl | LEON3_GPTIMER_CTRL_PENDING);
+	ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
+
+	if ((ctrl & LEON3_GPTIMER_CTRL_PENDING) != 0)
+		leon3_gptimer_ackmask = ~LEON3_GPTIMER_CTRL_PENDING;
+	else
+		leon3_gptimer_ackmask = ~0;
+
+	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
+	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
+				(((1000000 / HZ) - 1)));
+	LEON3_BYPASS_STORE_PA(
+			&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
+
+	/*
+	 * The IRQ controller may (if implemented) consist of multiple
+	 * IRQ controllers, each mapped on a 4Kb boundary.
+	 * Each CPU may be routed to different IRQCTRLs, however
+	 * we assume that all CPUs (in SMP system) is routed to the
+	 * same IRQ Controller, and for non-SMP only one IRQCTRL is
+	 * accessed anyway.
+	 * In AMP systems, Linux must run on CPU0 for the time being.
+	 */
+	icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
+	icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
+	leon3_irqctrl_regs += icsel;
+
+	/* Mask all IRQs on boot-cpu IRQ controller */
+	LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
+
+	/* Probe extended IRQ controller */
+	eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
+		>> 16) & 0xf;
+	if (eirq != 0)
+		leon_eirq_setup(eirq);
+
+#ifdef CONFIG_SMP
+	{
+		unsigned long flags;
+
+		/*
+		 * In SMP, sun4m adds a IPI handler to IRQ trap handler that
+		 * LEON never must take, sun4d and LEON overwrites the branch
+		 * with a NOP.
+		 */
+		local_irq_save(flags);
+		patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
+		local_ops->cache_all();
+		local_irq_restore(flags);
+	}
+#endif
+
+	config = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config);
+	if (config & (1 << LEON3_GPTIMER_SEPIRQ))
+		leon3_gptimer_irq += leon3_gptimer_idx;
+	else if ((config & LEON3_GPTIMER_TIMERS) > 1)
+		pr_warn("GPTIMER uses shared irqs, using other timers of the same core will fail.\n");
+
+#ifdef CONFIG_SMP
+	/* Install per-cpu IRQ handler for broadcasted ticker */
+	irq = leon_build_device_irq(leon3_gptimer_irq, handle_percpu_irq,
+				    "per-cpu", 0);
+	err = request_irq(irq, leon_percpu_timer_ce_interrupt,
+			  IRQF_PERCPU | IRQF_TIMER, "timer", NULL);
+#else
+	irq = _leon_build_device_irq(NULL, leon3_gptimer_irq);
+	err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
+#endif
+	if (err) {
+		pr_err("Unable to attach timer IRQ%d\n", irq);
+		prom_halt();
+	}
+	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
+			      LEON3_GPTIMER_EN |
+			      LEON3_GPTIMER_RL |
+			      LEON3_GPTIMER_LD |
+			      LEON3_GPTIMER_IRQEN);
+	return;
+bad:
+	printk(KERN_ERR "No Timer/irqctrl found\n");
+	BUG();
+	return;
+}
+
+static void leon_clear_clock_irq(void)
+{
+	u32 ctrl;
+
+	ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
+	LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
+			      ctrl & leon3_gptimer_ackmask);
+}
+
+static void leon_load_profile_irq(int cpu, unsigned int limit)
+{
+}
+
+#ifdef CONFIG_SMP
+void leon_clear_profile_irq(int cpu)
+{
+}
+
+void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
+{
+	unsigned long mask, flags, *addr;
+	mask = leon_get_irqmask(irq_nr);
+	spin_lock_irqsave(&leon_irq_lock, flags);
+	addr = (unsigned long *)LEON_IMASK(cpu);
+	LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
+	spin_unlock_irqrestore(&leon_irq_lock, flags);
+}
+
+#endif
+
+void __init leon_init_IRQ(void)
+{
+	sparc_config.init_timers      = leon_init_timers;
+	sparc_config.build_device_irq = _leon_build_device_irq;
+	sparc_config.clock_rate       = 1000000;
+	sparc_config.clear_clock_irq  = leon_clear_clock_irq;
+	sparc_config.load_profile_irq = leon_load_profile_irq;
+}