// 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 ([email protected])
* Copyright (C) 1995 Miguel de Icaza ([email protected])
* Copyright (C) 1995,2002 Pete A. Zaitcev ([email protected])
* Copyright (C) 1996 Dave Redman ([email protected])
* Copyright (C) 1998-2000 Anton Blanchard ([email protected])
*/
#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 ([email protected])
*
* 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[0];
INSTANTIATE(trap_table)
trap_table = &trapbase_cpu2[0];
INSTANTIATE(trap_table)
trap_table = &trapbase_cpu3[0];
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;
}
}
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