From 0ab2b7d08ea7226dc72ff0f8c05f470566facf7c Mon Sep 17 00:00:00 2001 From: Raghu Gandham Date: Wed, 10 Apr 2013 16:30:12 -0500 Subject: MIPS: Add new GIC clockevent driver. Add new clockevent driver that uses the counter present on the MIPS Global Interrupt Controller. Signed-off-by: Raghu Gandham Signed-off-by: Steven J. Hill diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 4b62305..44e29b64 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -912,6 +912,9 @@ config CEVT_GT641XX config CEVT_R4K bool +config CEVT_GIC + bool + config CEVT_SB1250 bool @@ -1819,6 +1822,15 @@ config FORCE_MAX_ZONEORDER The page size is not necessarily 4KB. Keep this in mind when choosing a value for this option. +config CEVT_GIC + bool "Use GIC global counter for clock events" + depends on IRQ_GIC && !(MIPS_SEAD3 || MIPS_MT_SMTC) + help + Use the GIC global counter for the clock events. The R4K clock + event driver is always present, so if the platform ends up not + detecting a GIC, it will fall back to the R4K timer for the + generation of clock events. + config BOARD_SCACHE bool diff --git a/arch/mips/include/asm/gic.h b/arch/mips/include/asm/gic.h index 398cf54..7153b32 100644 --- a/arch/mips/include/asm/gic.h +++ b/arch/mips/include/asm/gic.h @@ -202,7 +202,7 @@ #define GIC_VPE_WD_COUNT0_OFS 0x0094 #define GIC_VPE_WD_INITIAL0_OFS 0x0098 #define GIC_VPE_COMPARE_LO_OFS 0x00a0 -#define GIC_VPE_COMPARE_HI 0x00a4 +#define GIC_VPE_COMPARE_HI_OFS 0x00a4 #define GIC_VPE_EIC_SHADOW_SET_BASE 0x0100 #define GIC_VPE_EIC_SS(intr) \ @@ -373,7 +373,10 @@ extern void gic_init(unsigned long gic_base_addr, unsigned long gic_addrspace_size, struct gic_intr_map *intrmap, unsigned int intrmap_size, unsigned int irqbase); extern void gic_clocksource_init(unsigned int); +extern unsigned int gic_compare_int (void); extern cycle_t gic_read_count(void); +extern cycle_t gic_read_compare(void); +extern void gic_write_compare(cycle_t cnt); extern void gic_send_ipi(unsigned int intr); extern unsigned int plat_ipi_call_int_xlate(unsigned int); extern unsigned int plat_ipi_resched_int_xlate(unsigned int); diff --git a/arch/mips/include/asm/time.h b/arch/mips/include/asm/time.h index 4784218..2d7b9df 100644 --- a/arch/mips/include/asm/time.h +++ b/arch/mips/include/asm/time.h @@ -53,11 +53,14 @@ extern int (*perf_irq)(void); extern unsigned int __weak get_c0_compare_int(void); extern int r4k_clockevent_init(void); extern int smtc_clockevent_init(void); +extern int gic_clockevent_init(void); static inline int mips_clockevent_init(void) { #ifdef CONFIG_MIPS_MT_SMTC return smtc_clockevent_init(); +#elif defined(CONFIG_CEVT_GIC) + return (gic_clockevent_init() | r4k_clockevent_init()); #elif defined(CONFIG_CEVT_R4K) return r4k_clockevent_init(); #else diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index bab8b16..3d95062 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_CEVT_BCM1480) += cevt-bcm1480.o obj-$(CONFIG_CEVT_R4K) += cevt-r4k.o obj-$(CONFIG_MIPS_MT_SMTC) += cevt-smtc.o obj-$(CONFIG_CEVT_DS1287) += cevt-ds1287.o +obj-$(CONFIG_CEVT_GIC) += cevt-gic.o obj-$(CONFIG_CEVT_GT641XX) += cevt-gt641xx.o obj-$(CONFIG_CEVT_SB1250) += cevt-sb1250.o obj-$(CONFIG_CEVT_TXX9) += cevt-txx9.o diff --git a/arch/mips/kernel/cevt-gic.c b/arch/mips/kernel/cevt-gic.c new file mode 100644 index 0000000..730eaf9 --- /dev/null +++ b/arch/mips/kernel/cevt-gic.c @@ -0,0 +1,104 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2013 Imagination Technologies Ltd. + */ +#include +#include +#include +#include +#include + +#include +#include +#include + +DEFINE_PER_CPU(struct clock_event_device, gic_clockevent_device); +int gic_timer_irq_installed; + + +static int gic_next_event(unsigned long delta, struct clock_event_device *evt) +{ + u64 cnt; + int res; + + cnt = gic_read_count(); + cnt += (u64)delta; + gic_write_compare(cnt); + res = ((int)(gic_read_count() - cnt) >= 0) ? -ETIME : 0; + return res; +} + +void gic_set_clock_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + /* Nothing to do ... */ +} + +irqreturn_t gic_compare_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *cd; + int cpu = smp_processor_id(); + + gic_write_compare(gic_read_compare()); + cd = &per_cpu(gic_clockevent_device, cpu); + cd->event_handler(cd); + return IRQ_HANDLED; +} + +struct irqaction gic_compare_irqaction = { + .handler = gic_compare_interrupt, + .flags = IRQF_PERCPU | IRQF_TIMER, + .name = "timer", +}; + + +void gic_event_handler(struct clock_event_device *dev) +{ +} + +int __cpuinit gic_clockevent_init(void) +{ + unsigned int cpu = smp_processor_id(); + struct clock_event_device *cd; + unsigned int irq; + + if (!cpu_has_counter || !gic_frequency) + return -ENXIO; + + irq = MIPS_GIC_IRQ_BASE; + + cd = &per_cpu(gic_clockevent_device, cpu); + + cd->name = "MIPS GIC"; + cd->features = CLOCK_EVT_FEAT_ONESHOT; + + clockevent_set_clock(cd, gic_frequency); + + /* Calculate the min / max delta */ + cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd); + cd->min_delta_ns = clockevent_delta2ns(0x300, cd); + + cd->rating = 300; + cd->irq = irq; + cd->cpumask = cpumask_of(cpu); + cd->set_next_event = gic_next_event; + cd->set_mode = gic_set_clock_mode; + cd->event_handler = gic_event_handler; + + clockevents_register_device(cd); + + GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_MAP), 0x80000002); + GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_SMASK), GIC_VPE_SMASK_CMP_MSK); + + if (gic_timer_irq_installed) + return 0; + + gic_timer_irq_installed = 1; + + setup_irq(irq, &gic_compare_irqaction); + irq_set_handler(irq, handle_percpu_irq); + return 0; +} diff --git a/arch/mips/kernel/cevt-r4k.c b/arch/mips/kernel/cevt-r4k.c index 0309aef..0613f46 100644 --- a/arch/mips/kernel/cevt-r4k.c +++ b/arch/mips/kernel/cevt-r4k.c @@ -72,6 +72,9 @@ irqreturn_t c0_compare_interrupt(int irq, void *dev_id) /* Clear Count/Compare Interrupt */ write_c0_compare(read_c0_compare()); cd = &per_cpu(mips_clockevent_device, cpu); +#ifdef CONFIG_CEVT_GIC + if (!gic_present) +#endif cd->event_handler(cd); } @@ -203,6 +206,9 @@ int __cpuinit r4k_clockevent_init(void) cd->set_mode = mips_set_clock_mode; cd->event_handler = mips_event_handler; +#ifdef CONFIG_CEVT_GIC + if (!gic_present) +#endif clockevents_register_device(cd); if (cp0_timer_irq_installed) diff --git a/arch/mips/kernel/irq-gic.c b/arch/mips/kernel/irq-gic.c index 6a476e1..c01b307 100644 --- a/arch/mips/kernel/irq-gic.c +++ b/arch/mips/kernel/irq-gic.c @@ -33,7 +33,7 @@ static struct gic_pcpu_mask pcpu_masks[NR_CPUS]; static struct gic_pending_regs pending_regs[NR_CPUS]; static struct gic_intrmask_regs intrmask_regs[NR_CPUS]; -#ifdef CONFIG_CSRC_GIC +#if defined(CONFIG_CSRC_GIC) || defined(CONFIG_CEVT_GIC) cycle_t gic_read_count(void) { unsigned int hi, hi2, lo; @@ -46,6 +46,24 @@ cycle_t gic_read_count(void) return (((cycle_t) hi) << 32) + lo; } + +void gic_write_compare(cycle_t cnt) +{ + GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_HI), + (int)(cnt >> 32)); + GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_LO), + (int)(cnt & 0xffffffff)); +} + +cycle_t gic_read_compare(void) +{ + unsigned int hi, lo; + + GICREAD(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_HI), hi); + GICREAD(GIC_REG(VPE_LOCAL, GIC_VPE_COMPARE_LO), lo); + + return (((cycle_t) hi) << 32) + lo; +} #endif unsigned int gic_get_timer_pending(void) @@ -134,6 +152,17 @@ static void __init vpe_local_setup(unsigned int numvpes) } } +unsigned int gic_compare_int(void) +{ + unsigned int pending; + + GICREAD(GIC_REG(VPE_LOCAL, GIC_VPE_PEND), pending); + if (pending & GIC_VPE_PEND_CMP_MSK) + return 1; + else + return 0; +} + unsigned int gic_get_int(void) { unsigned int i; diff --git a/arch/mips/mti-malta/malta-int.c b/arch/mips/mti-malta/malta-int.c index 8e840c2..0a1339a 100644 --- a/arch/mips/mti-malta/malta-int.c +++ b/arch/mips/mti-malta/malta-int.c @@ -133,6 +133,9 @@ static void malta_ipi_irqdispatch(void) { int irq; + if (gic_compare_int()) + do_IRQ(MIPS_GIC_IRQ_BASE); + irq = gic_get_int(); if (irq < 0) return; /* interrupt has already been cleared */ -- cgit v0.10.2