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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/sparc/kernel/sun4d_irq.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/sparc/kernel/sun4d_irq.c')
-rw-r--r-- | arch/sparc/kernel/sun4d_irq.c | 519 |
1 files changed, 519 insertions, 0 deletions
diff --git a/arch/sparc/kernel/sun4d_irq.c b/arch/sparc/kernel/sun4d_irq.c new file mode 100644 index 000000000..9a137c70e --- /dev/null +++ b/arch/sparc/kernel/sun4d_irq.c @@ -0,0 +1,519 @@ +// 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. */ +} |