diff options
Diffstat (limited to 'arch/mips/kernel/cevt-sb1250.c')
| -rw-r--r-- | arch/mips/kernel/cevt-sb1250.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/arch/mips/kernel/cevt-sb1250.c b/arch/mips/kernel/cevt-sb1250.c new file mode 100644 index 00000000000..e2029d0fc39 --- /dev/null +++ b/arch/mips/kernel/cevt-sb1250.c @@ -0,0 +1,148 @@ +/* + * Copyright (C) 2000, 2001 Broadcom Corporation + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ +#include <linux/clockchips.h> +#include <linux/interrupt.h> +#include <linux/percpu.h> + +#include <asm/addrspace.h> +#include <asm/io.h> +#include <asm/time.h> + +#include <asm/sibyte/sb1250.h> +#include <asm/sibyte/sb1250_regs.h> +#include <asm/sibyte/sb1250_int.h> +#include <asm/sibyte/sb1250_scd.h> + +#define IMR_IP2_VAL K_INT_MAP_I0 +#define IMR_IP3_VAL K_INT_MAP_I1 +#define IMR_IP4_VAL K_INT_MAP_I2 + +/* + * The general purpose timer ticks at 1MHz independent if + * the rest of the system + */ +static void sibyte_set_mode(enum clock_event_mode mode, + 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)); + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + __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); + break; + + case CLOCK_EVT_MODE_ONESHOT: + /* Stop the timer until we actually program a shot */ + case CLOCK_EVT_MODE_SHUTDOWN: + __raw_writeq(0, cfg); + break; + + case CLOCK_EVT_MODE_UNUSED: /* shuddup gcc */ + case CLOCK_EVT_MODE_RESUME: + ; + } +} + +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(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 (cd->mode == CLOCK_EVT_MODE_PERIODIC) + 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(struct irqaction, sibyte_hpt_irqaction); +static DEFINE_PER_CPU(char [18], sibyte_hpt_name); + +void __cpuinit sb1250_clockevent_init(void) +{ + unsigned int cpu = smp_processor_id(); + unsigned int irq = K_INT_TIMER_0 + cpu; + struct irqaction *action = &per_cpu(sibyte_hpt_irqaction, cpu); + struct clock_event_device *cd = &per_cpu(sibyte_hpt_clockevent, cpu); + unsigned char *name = per_cpu(sibyte_hpt_name, cpu); + + /* Only have 4 general purpose timers, and we use last one as hpt */ + BUG_ON(cpu > 2); + + sprintf(name, "sb1250-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->min_delta_ns = clockevent_delta2ns(1, cd); + cd->rating = 200; + cd->irq = irq; + cd->cpumask = cpumask_of_cpu(cpu); + cd->set_next_event = sibyte_next_event; + cd->set_mode = sibyte_set_mode; + clockevents_register_device(cd); + + sb1250_mask_irq(cpu, irq); + + /* + * Map the timer interrupt to IP[4] of this cpu + */ + __raw_writeq(IMR_IP4_VAL, + IOADDR(A_IMR_REGISTER(cpu, R_IMR_INTERRUPT_MAP_BASE) + + (irq << 3))); + + sb1250_unmask_irq(cpu, irq); + + action->handler = sibyte_counter_handler; + action->flags = IRQF_DISABLED | IRQF_PERCPU; + action->name = name; + action->dev_id = cd; + setup_irq(irq, action); +} |