linux/arch/sparc/kernel/sun4d_irq.c
Rob Herring 29c990dfc7 sparc: Use of_node_name_eq for node name comparisons
Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-18 13:35:21 -08:00

520 lines
12 KiB
C

// 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. */
}