linux/arch/sparc/kernel/sun4d_irq.c
oftedal 9eeb08986f Add support for allocating irqs for bootbus devices
Some devices that can generate interrupts are connected directly to the
CPU through the bootbus on sun4d. This patch allows IRQs to be allocated
for such devices. The information used for allocating interrupts for
sbus devices are present at the corresponding SBI node. For bootbus
devices this information is present in the bootbus node.

Signed-off-by: Kjetil Oftedal <oftedal@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-07 16:06:33 -07:00

525 lines
12 KiB
C

/*
* 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/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 "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(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);
}
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
static void sun4d_set_cpu_int(int cpu, int level)
{
sun4d_send_ipi(cpu, level);
}
static void sun4d_clear_ipi(int cpu, int level)
{
}
static void sun4d_set_udt(int cpu)
{
}
/* 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)
{
bw_set_prof_limit(cpu, limit);
}
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++;
}
}
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;
}
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;
}
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_flush_cache_all();
local_irq_restore(flags);
#endif
}
static void __init sun4d_init_timers(irq_handler_t counter_fn)
{
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();
}
sbus_writel((((1000000/HZ) + 1) << 10), &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, counter_fn, 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();
BTFIXUPSET_CALL(clear_clock_irq, sun4d_clear_clock_irq, BTFIXUPCALL_NORM);
BTFIXUPSET_CALL(load_profile_irq, sun4d_load_profile_irq, BTFIXUPCALL_NORM);
sparc_irq_config.init_timers = sun4d_init_timers;
sparc_irq_config.build_device_irq = sun4d_build_device_irq;
#ifdef CONFIG_SMP
BTFIXUPSET_CALL(set_cpu_int, sun4d_set_cpu_int, BTFIXUPCALL_NORM);
BTFIXUPSET_CALL(clear_cpu_int, sun4d_clear_ipi, BTFIXUPCALL_NOP);
BTFIXUPSET_CALL(set_irq_udt, sun4d_set_udt, BTFIXUPCALL_NOP);
#endif
/* Cannot enable interrupts until OBP ticker is disabled. */
}