diff options
Diffstat (limited to 'arch/mips/kernel/cevt-bcm1480.c')
| -rw-r--r-- | arch/mips/kernel/cevt-bcm1480.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/mips/kernel/cevt-bcm1480.c b/arch/mips/kernel/cevt-bcm1480.c new file mode 100644 index 000000000..d39a2963b --- /dev/null +++ b/arch/mips/kernel/cevt-bcm1480.c @@ -0,0 +1,138 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2000,2001,2004 Broadcom Corporation + */ +#include <linux/clockchips.h> +#include <linux/interrupt.h> +#include <linux/percpu.h> +#include <linux/smp.h> +#include <linux/irq.h> + +#include <asm/addrspace.h> +#include <asm/io.h> +#include <asm/time.h> + +#include <asm/sibyte/bcm1480_regs.h> +#include <asm/sibyte/sb1250_regs.h> +#include <asm/sibyte/bcm1480_int.h> +#include <asm/sibyte/bcm1480_scd.h> + +#include <asm/sibyte/sb1250.h> + +#define IMR_IP2_VAL K_BCM1480_INT_MAP_I0 +#define IMR_IP3_VAL K_BCM1480_INT_MAP_I1 +#define IMR_IP4_VAL K_BCM1480_INT_MAP_I2 + +/* + * The general purpose timer ticks at 1MHz independent if + * the rest of the system + */ + +static int sibyte_set_periodic(struct clock_event_device *evt) +{ + unsigned int cpu = smp_processor_id(); + void __iomem *cfg, *init; + + cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)); + init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT)); + + __raw_writeq(0, cfg); + __raw_writeq((V_SCD_TIMER_FREQ / HZ) - 1, init); + __raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS, cfg); + return 0; +} + +static int sibyte_shutdown(struct clock_event_device *evt) +{ + unsigned int cpu = smp_processor_id(); + void __iomem *cfg; + + cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)); + + /* Stop the timer until we actually program a shot */ + __raw_writeq(0, cfg); + return 0; +} + +static int sibyte_next_event(unsigned long delta, struct clock_event_device *cd) +{ + unsigned int cpu = smp_processor_id(); + void __iomem *cfg, *init; + + cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)); + init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT)); + + __raw_writeq(0, cfg); + __raw_writeq(delta - 1, init); + __raw_writeq(M_SCD_TIMER_ENABLE, cfg); + + return 0; +} + +static irqreturn_t sibyte_counter_handler(int irq, void *dev_id) +{ + unsigned int cpu = smp_processor_id(); + struct clock_event_device *cd = dev_id; + void __iomem *cfg; + unsigned long tmode; + + if (clockevent_state_periodic(cd)) + tmode = M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS; + else + tmode = 0; + + /* ACK interrupt */ + cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)); + ____raw_writeq(tmode, cfg); + + cd->event_handler(cd); + + return IRQ_HANDLED; +} + +static DEFINE_PER_CPU(struct clock_event_device, sibyte_hpt_clockevent); +static DEFINE_PER_CPU(char [18], sibyte_hpt_name); + +void sb1480_clockevent_init(void) +{ + unsigned int cpu = smp_processor_id(); + unsigned int irq = K_BCM1480_INT_TIMER_0 + cpu; + struct clock_event_device *cd = &per_cpu(sibyte_hpt_clockevent, cpu); + unsigned char *name = per_cpu(sibyte_hpt_name, cpu); + unsigned long flags = IRQF_PERCPU | IRQF_TIMER; + + BUG_ON(cpu > 3); /* Only have 4 general purpose timers */ + + sprintf(name, "bcm1480-counter-%d", cpu); + cd->name = name; + cd->features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT; + clockevent_set_clock(cd, V_SCD_TIMER_FREQ); + cd->max_delta_ns = clockevent_delta2ns(0x7fffff, cd); + cd->max_delta_ticks = 0x7fffff; + cd->min_delta_ns = clockevent_delta2ns(2, cd); + cd->min_delta_ticks = 2; + cd->rating = 200; + cd->irq = irq; + cd->cpumask = cpumask_of(cpu); + cd->set_next_event = sibyte_next_event; + cd->set_state_shutdown = sibyte_shutdown; + cd->set_state_periodic = sibyte_set_periodic; + cd->set_state_oneshot = sibyte_shutdown; + clockevents_register_device(cd); + + bcm1480_mask_irq(cpu, irq); + + /* + * Map the timer interrupt to IP[4] of this cpu + */ + __raw_writeq(IMR_IP4_VAL, + IOADDR(A_BCM1480_IMR_REGISTER(cpu, + R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) + (irq << 3))); + + bcm1480_unmask_irq(cpu, irq); + + irq_set_affinity(irq, cpumask_of(cpu)); + if (request_irq(irq, sibyte_counter_handler, flags, name, cd)) + pr_err("Failed to request irq %d (%s)\n", irq, name); +} |