1 files changed, 363 insertions, 0 deletions
diff --git a/arch/sparc/kernel/irq_32.c b/arch/sparc/kernel/irq_32.c
new file mode 100644
index 000000000..e8452be51
--- /dev/null
+++ b/arch/sparc/kernel/irq_32.c
@@ -0,0 +1,363 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Interrupt request handling routines. On the
+ * Sparc the IRQs are basically 'cast in stone'
+ * and you are supposed to probe the prom's device
+ * node trees to find out who's got which IRQ.
+ *
+ *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
+ *  Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx)
+ *  Copyright (C) 1995,2002 Pete A. Zaitcev (zaitcev@yahoo.com)
+ *  Copyright (C) 1996 Dave Redman (djhr@tadpole.co.uk)
+ *  Copyright (C) 1998-2000 Anton Blanchard (anton@samba.org)
+ */
+
+#include <linux/kernel_stat.h>
+#include <linux/seq_file.h>
+#include <linux/export.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cpudata.h>
+#include <asm/setup.h>
+#include <asm/pcic.h>
+#include <asm/leon.h>
+
+#include "kernel.h"
+#include "irq.h"
+
+/* platform specific irq setup */
+struct sparc_config sparc_config;
+
+unsigned long arch_local_irq_save(void)
+{
+	unsigned long retval;
+	unsigned long tmp;
+
+	__asm__ __volatile__(
+		"rd	%%psr, %0\n\t"
+		"or	%0, %2, %1\n\t"
+		"wr	%1, 0, %%psr\n\t"
+		"nop; nop; nop\n"
+		: "=&r" (retval), "=r" (tmp)
+		: "i" (PSR_PIL)
+		: "memory");
+
+	return retval;
+}
+EXPORT_SYMBOL(arch_local_irq_save);
+
+void arch_local_irq_enable(void)
+{
+	unsigned long tmp;
+
+	__asm__ __volatile__(
+		"rd	%%psr, %0\n\t"
+		"andn	%0, %1, %0\n\t"
+		"wr	%0, 0, %%psr\n\t"
+		"nop; nop; nop\n"
+		: "=&r" (tmp)
+		: "i" (PSR_PIL)
+		: "memory");
+}
+EXPORT_SYMBOL(arch_local_irq_enable);
+
+void arch_local_irq_restore(unsigned long old_psr)
+{
+	unsigned long tmp;
+
+	__asm__ __volatile__(
+		"rd	%%psr, %0\n\t"
+		"and	%2, %1, %2\n\t"
+		"andn	%0, %1, %0\n\t"
+		"wr	%0, %2, %%psr\n\t"
+		"nop; nop; nop\n"
+		: "=&r" (tmp)
+		: "i" (PSR_PIL), "r" (old_psr)
+		: "memory");
+}
+EXPORT_SYMBOL(arch_local_irq_restore);
+
+/*
+ * Dave Redman (djhr@tadpole.co.uk)
+ *
+ * IRQ numbers.. These are no longer restricted to 15..
+ *
+ * this is done to enable SBUS cards and onboard IO to be masked
+ * correctly. using the interrupt level isn't good enough.
+ *
+ * For example:
+ *   A device interrupting at sbus level6 and the Floppy both come in
+ *   at IRQ11, but enabling and disabling them requires writing to
+ *   different bits in the SLAVIO/SEC.
+ *
+ * As a result of these changes sun4m machines could now support
+ * directed CPU interrupts using the existing enable/disable irq code
+ * with tweaks.
+ *
+ * Sun4d complicates things even further.  IRQ numbers are arbitrary
+ * 32-bit values in that case.  Since this is similar to sparc64,
+ * we adopt a virtual IRQ numbering scheme as is done there.
+ * Virutal interrupt numbers are allocated by build_irq().  So NR_IRQS
+ * just becomes a limit of how many interrupt sources we can handle in
+ * a single system.  Even fully loaded SS2000 machines top off at
+ * about 32 interrupt sources or so, therefore a NR_IRQS value of 64
+ * is more than enough.
+  *
+ * We keep a map of per-PIL enable interrupts.  These get wired
+ * up via the irq_chip->startup() method which gets invoked by
+ * the generic IRQ layer during request_irq().
+ */
+
+
+/* Table of allocated irqs. Unused entries has irq == 0 */
+static struct irq_bucket irq_table[NR_IRQS];
+/* Protect access to irq_table */
+static DEFINE_SPINLOCK(irq_table_lock);
+
+/* Map between the irq identifier used in hw to the irq_bucket. */
+struct irq_bucket *irq_map[SUN4D_MAX_IRQ];
+/* Protect access to irq_map */
+static DEFINE_SPINLOCK(irq_map_lock);
+
+/* Allocate a new irq from the irq_table */
+unsigned int irq_alloc(unsigned int real_irq, unsigned int pil)
+{
+	unsigned long flags;
+	unsigned int i;
+
+	spin_lock_irqsave(&irq_table_lock, flags);
+	for (i = 1; i < NR_IRQS; i++) {
+		if (irq_table[i].real_irq == real_irq && irq_table[i].pil == pil)
+			goto found;
+	}
+
+	for (i = 1; i < NR_IRQS; i++) {
+		if (!irq_table[i].irq)
+			break;
+	}
+
+	if (i < NR_IRQS) {
+		irq_table[i].real_irq = real_irq;
+		irq_table[i].irq = i;
+		irq_table[i].pil = pil;
+	} else {
+		printk(KERN_ERR "IRQ: Out of virtual IRQs.\n");
+		i = 0;
+	}
+found:
+	spin_unlock_irqrestore(&irq_table_lock, flags);
+
+	return i;
+}
+
+/* Based on a single pil handler_irq may need to call several
+ * interrupt handlers. Use irq_map as entry to irq_table,
+ * and let each entry in irq_table point to the next entry.
+ */
+void irq_link(unsigned int irq)
+{
+	struct irq_bucket *p;
+	unsigned long flags;
+	unsigned int pil;
+
+	BUG_ON(irq >= NR_IRQS);
+
+	spin_lock_irqsave(&irq_map_lock, flags);
+
+	p = &irq_table[irq];
+	pil = p->pil;
+	BUG_ON(pil >= SUN4D_MAX_IRQ);
+	p->next = irq_map[pil];
+	irq_map[pil] = p;
+
+	spin_unlock_irqrestore(&irq_map_lock, flags);
+}
+
+void irq_unlink(unsigned int irq)
+{
+	struct irq_bucket *p, **pnext;
+	unsigned long flags;
+
+	BUG_ON(irq >= NR_IRQS);
+
+	spin_lock_irqsave(&irq_map_lock, flags);
+
+	p = &irq_table[irq];
+	BUG_ON(p->pil >= SUN4D_MAX_IRQ);
+	pnext = &irq_map[p->pil];
+	while (*pnext != p)
+		pnext = &(*pnext)->next;
+	*pnext = p->next;
+
+	spin_unlock_irqrestore(&irq_map_lock, flags);
+}
+
+
+/* /proc/interrupts printing */
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+	int j;
+
+#ifdef CONFIG_SMP
+	seq_printf(p, "RES: ");
+	for_each_online_cpu(j)
+		seq_printf(p, "%10u ", cpu_data(j).irq_resched_count);
+	seq_printf(p, "     IPI rescheduling interrupts\n");
+	seq_printf(p, "CAL: ");
+	for_each_online_cpu(j)
+		seq_printf(p, "%10u ", cpu_data(j).irq_call_count);
+	seq_printf(p, "     IPI function call interrupts\n");
+#endif
+	seq_printf(p, "NMI: ");
+	for_each_online_cpu(j)
+		seq_printf(p, "%10u ", cpu_data(j).counter);
+	seq_printf(p, "     Non-maskable interrupts\n");
+	return 0;
+}
+
+void handler_irq(unsigned int pil, struct pt_regs *regs)
+{
+	struct pt_regs *old_regs;
+	struct irq_bucket *p;
+
+	BUG_ON(pil > 15);
+	old_regs = set_irq_regs(regs);
+	irq_enter();
+
+	p = irq_map[pil];
+	while (p) {
+		struct irq_bucket *next = p->next;
+
+		generic_handle_irq(p->irq);
+		p = next;
+	}
+	irq_exit();
+	set_irq_regs(old_regs);
+}
+
+#if defined(CONFIG_BLK_DEV_FD) || defined(CONFIG_BLK_DEV_FD_MODULE)
+static unsigned int floppy_irq;
+
+int sparc_floppy_request_irq(unsigned int irq, irq_handler_t irq_handler)
+{
+	unsigned int cpu_irq;
+	int err;
+
+
+	err = request_irq(irq, irq_handler, 0, "floppy", NULL);
+	if (err)
+		return -1;
+
+	/* Save for later use in floppy interrupt handler */
+	floppy_irq = irq;
+
+	cpu_irq = (irq & (NR_IRQS - 1));
+
+	/* Dork with trap table if we get this far. */
+#define INSTANTIATE(table) \
+	table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_one = SPARC_RD_PSR_L0; \
+	table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two = \
+		SPARC_BRANCH((unsigned long) floppy_hardint, \
+			     (unsigned long) &table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two);\
+	table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_three = SPARC_RD_WIM_L3; \
+	table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_four = SPARC_NOP;
+
+	INSTANTIATE(sparc_ttable)
+
+#if defined CONFIG_SMP
+	if (sparc_cpu_model != sparc_leon) {
+		struct tt_entry *trap_table;
+
+		trap_table = &trapbase_cpu1;
+		INSTANTIATE(trap_table)
+		trap_table = &trapbase_cpu2;
+		INSTANTIATE(trap_table)
+		trap_table = &trapbase_cpu3;
+		INSTANTIATE(trap_table)
+	}
+#endif
+#undef INSTANTIATE
+	/*
+	 * XXX Correct thing whould be to flush only I- and D-cache lines
+	 * which contain the handler in question. But as of time of the
+	 * writing we have no CPU-neutral interface to fine-grained flushes.
+	 */
+	flush_cache_all();
+	return 0;
+}
+EXPORT_SYMBOL(sparc_floppy_request_irq);
+
+/*
+ * These variables are used to access state from the assembler
+ * interrupt handler, floppy_hardint, so we cannot put these in
+ * the floppy driver image because that would not work in the
+ * modular case.
+ */
+volatile unsigned char *fdc_status;
+EXPORT_SYMBOL(fdc_status);
+
+char *pdma_vaddr;
+EXPORT_SYMBOL(pdma_vaddr);
+
+unsigned long pdma_size;
+EXPORT_SYMBOL(pdma_size);
+
+volatile int doing_pdma;
+EXPORT_SYMBOL(doing_pdma);
+
+char *pdma_base;
+EXPORT_SYMBOL(pdma_base);
+
+unsigned long pdma_areasize;
+EXPORT_SYMBOL(pdma_areasize);
+
+/* Use the generic irq support to call floppy_interrupt
+ * which was setup using request_irq() in sparc_floppy_request_irq().
+ * We only have one floppy interrupt so we do not need to check
+ * for additional handlers being wired up by irq_link()
+ */
+void sparc_floppy_irq(int irq, void *dev_id, struct pt_regs *regs)
+{
+	struct pt_regs *old_regs;
+
+	old_regs = set_irq_regs(regs);
+	irq_enter();
+	generic_handle_irq(floppy_irq);
+	irq_exit();
+	set_irq_regs(old_regs);
+}
+#endif
+
+/* djhr
+ * This could probably be made indirect too and assigned in the CPU
+ * bits of the code. That would be much nicer I think and would also
+ * fit in with the idea of being able to tune your kernel for your machine
+ * by removing unrequired machine and device support.
+ *
+ */
+
+void __init init_IRQ(void)
+{
+	switch (sparc_cpu_model) {
+	case sun4m:
+		pcic_probe();
+		if (pcic_present())
+			sun4m_pci_init_IRQ();
+		else
+			sun4m_init_IRQ();
+		break;
+
+	case sun4d:
+		sun4d_init_IRQ();
+		break;
+
+	case sparc_leon:
+		leon_init_IRQ();
+		break;
+
+	default:
+		prom_printf("Cannot initialize IRQs on this Sun machine...");
+		break;
+	}
+}
+