diff options
Diffstat (limited to 'drivers/ptp')
| -rw-r--r-- | drivers/ptp/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/ptp/Makefile | 1 | ||||
| -rw-r--r-- | drivers/ptp/ptp_ixp46x.c | 332 |
3 files changed, 346 insertions, 0 deletions
diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig index 12eb844..fcfafd0 100644 --- a/drivers/ptp/Kconfig +++ b/drivers/ptp/Kconfig @@ -40,4 +40,17 @@ config PTP_1588_CLOCK_GIANFAR To compile this driver as a module, choose M here: the module will be called gianfar_ptp. +config PTP_1588_CLOCK_IXP46X + tristate "Intel IXP46x as PTP clock" + depends on PTP_1588_CLOCK + depends on IXP4XX_ETH + help + This driver adds support for using the IXP46X as a PTP + clock. This clock is only useful if your PTP programs are + getting hardware time stamps on the PTP Ethernet packets + using the SO_TIMESTAMPING API. + + To compile this driver as a module, choose M here: the module + will be called ptp_ixp46x. + endmenu diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile index 480e2af..f6933e8 100644 --- a/drivers/ptp/Makefile +++ b/drivers/ptp/Makefile @@ -4,3 +4,4 @@ ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o obj-$(CONFIG_PTP_1588_CLOCK) += ptp.o +obj-$(CONFIG_PTP_1588_CLOCK_IXP46X) += ptp_ixp46x.o diff --git a/drivers/ptp/ptp_ixp46x.c b/drivers/ptp/ptp_ixp46x.c new file mode 100644 index 0000000..803d665 --- /dev/null +++ b/drivers/ptp/ptp_ixp46x.c @@ -0,0 +1,332 @@ +/* + * PTP 1588 clock using the IXP46X + * + * Copyright (C) 2010 OMICRON electronics GmbH + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + */ +#include <linux/device.h> +#include <linux/err.h> +#include <linux/gpio.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/module.h> + +#include <linux/ptp_clock_kernel.h> +#include <mach/ixp46x_ts.h> + +#define DRIVER "ptp_ixp46x" +#define N_EXT_TS 2 +#define MASTER_GPIO 8 +#define MASTER_IRQ 25 +#define SLAVE_GPIO 7 +#define SLAVE_IRQ 24 + +struct ixp_clock { + struct ixp46x_ts_regs *regs; + struct ptp_clock *ptp_clock; + struct ptp_clock_info caps; + int exts0_enabled; + int exts1_enabled; +}; + +DEFINE_SPINLOCK(register_lock); + +/* + * Register access functions + */ + +static u64 ixp_systime_read(struct ixp46x_ts_regs *regs) +{ + u64 ns; + u32 lo, hi; + + lo = __raw_readl(®s->systime_lo); + hi = __raw_readl(®s->systime_hi); + + ns = ((u64) hi) << 32; + ns |= lo; + ns <<= TICKS_NS_SHIFT; + + return ns; +} + +static void ixp_systime_write(struct ixp46x_ts_regs *regs, u64 ns) +{ + u32 hi, lo; + + ns >>= TICKS_NS_SHIFT; + hi = ns >> 32; + lo = ns & 0xffffffff; + + __raw_writel(lo, ®s->systime_lo); + __raw_writel(hi, ®s->systime_hi); +} + +/* + * Interrupt service routine + */ + +static irqreturn_t isr(int irq, void *priv) +{ + struct ixp_clock *ixp_clock = priv; + struct ixp46x_ts_regs *regs = ixp_clock->regs; + struct ptp_clock_event event; + u32 ack = 0, lo, hi, val; + + val = __raw_readl(®s->event); + + if (val & TSER_SNS) { + ack |= TSER_SNS; + if (ixp_clock->exts0_enabled) { + hi = __raw_readl(®s->asms_hi); + lo = __raw_readl(®s->asms_lo); + event.type = PTP_CLOCK_EXTTS; + event.index = 0; + event.timestamp = ((u64) hi) << 32; + event.timestamp |= lo; + event.timestamp <<= TICKS_NS_SHIFT; + ptp_clock_event(ixp_clock->ptp_clock, &event); + } + } + + if (val & TSER_SNM) { + ack |= TSER_SNM; + if (ixp_clock->exts1_enabled) { + hi = __raw_readl(®s->amms_hi); + lo = __raw_readl(®s->amms_lo); + event.type = PTP_CLOCK_EXTTS; + event.index = 1; + event.timestamp = ((u64) hi) << 32; + event.timestamp |= lo; + event.timestamp <<= TICKS_NS_SHIFT; + ptp_clock_event(ixp_clock->ptp_clock, &event); + } + } + + if (val & TTIPEND) + ack |= TTIPEND; /* this bit seems to be always set */ + + if (ack) { + __raw_writel(ack, ®s->event); + return IRQ_HANDLED; + } else + return IRQ_NONE; +} + +/* + * PTP clock operations + */ + +static int ptp_ixp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) +{ + u64 adj; + u32 diff, addend; + int neg_adj = 0; + struct ixp_clock *ixp_clock = container_of(ptp, struct ixp_clock, caps); + struct ixp46x_ts_regs *regs = ixp_clock->regs; + + if (ppb < 0) { + neg_adj = 1; + ppb = -ppb; + } + addend = DEFAULT_ADDEND; + adj = addend; + adj *= ppb; + diff = div_u64(adj, 1000000000ULL); + + addend = neg_adj ? addend - diff : addend + diff; + + __raw_writel(addend, ®s->addend); + + return 0; +} + +static int ptp_ixp_adjtime(struct ptp_clock_info *ptp, s64 delta) +{ + s64 now; + unsigned long flags; + struct ixp_clock *ixp_clock = container_of(ptp, struct ixp_clock, caps); + struct ixp46x_ts_regs *regs = ixp_clock->regs; + + spin_lock_irqsave(®ister_lock, flags); + + now = ixp_systime_read(regs); + now += delta; + ixp_systime_write(regs, now); + + spin_unlock_irqrestore(®ister_lock, flags); + + return 0; +} + +static int ptp_ixp_gettime(struct ptp_clock_info *ptp, struct timespec *ts) +{ + u64 ns; + u32 remainder; + unsigned long flags; + struct ixp_clock *ixp_clock = container_of(ptp, struct ixp_clock, caps); + struct ixp46x_ts_regs *regs = ixp_clock->regs; + + spin_lock_irqsave(®ister_lock, flags); + + ns = ixp_systime_read(regs); + + spin_unlock_irqrestore(®ister_lock, flags); + + ts->tv_sec = div_u64_rem(ns, 1000000000, &remainder); + ts->tv_nsec = remainder; + return 0; +} + +static int ptp_ixp_settime(struct ptp_clock_info *ptp, + const struct timespec *ts) +{ + u64 ns; + unsigned long flags; + struct ixp_clock *ixp_clock = container_of(ptp, struct ixp_clock, caps); + struct ixp46x_ts_regs *regs = ixp_clock->regs; + + ns = ts->tv_sec * 1000000000ULL; + ns += ts->tv_nsec; + + spin_lock_irqsave(®ister_lock, flags); + + ixp_systime_write(regs, ns); + + spin_unlock_irqrestore(®ister_lock, flags); + + return 0; +} + +static int ptp_ixp_enable(struct ptp_clock_info *ptp, + struct ptp_clock_request *rq, int on) +{ + struct ixp_clock *ixp_clock = container_of(ptp, struct ixp_clock, caps); + + switch (rq->type) { + case PTP_CLK_REQ_EXTTS: + switch (rq->extts.index) { + case 0: + ixp_clock->exts0_enabled = on ? 1 : 0; + break; + case 1: + ixp_clock->exts1_enabled = on ? 1 : 0; + break; + default: + return -EINVAL; + } + return 0; + default: + break; + } + + return -EOPNOTSUPP; +} + +static struct ptp_clock_info ptp_ixp_caps = { + .owner = THIS_MODULE, + .name = "IXP46X timer", + .max_adj = 66666655, + .n_ext_ts = N_EXT_TS, + .pps = 0, + .adjfreq = ptp_ixp_adjfreq, + .adjtime = ptp_ixp_adjtime, + .gettime = ptp_ixp_gettime, + .settime = ptp_ixp_settime, + .enable = ptp_ixp_enable, +}; + +/* module operations */ + +static struct ixp_clock ixp_clock; + +static int setup_interrupt(int gpio) +{ + int irq; + + gpio_line_config(gpio, IXP4XX_GPIO_IN); + + irq = gpio_to_irq(gpio); + + if (NO_IRQ == irq) + return NO_IRQ; + + if (irq_set_irq_type(irq, IRQF_TRIGGER_FALLING)) { + pr_err("cannot set trigger type for irq %d\n", irq); + return NO_IRQ; + } + + if (request_irq(irq, isr, 0, DRIVER, &ixp_clock)) { + pr_err("request_irq failed for irq %d\n", irq); + return NO_IRQ; + } + + return irq; +} + +static void __exit ptp_ixp_exit(void) +{ + free_irq(MASTER_IRQ, &ixp_clock); + free_irq(SLAVE_IRQ, &ixp_clock); + ptp_clock_unregister(ixp_clock.ptp_clock); +} + +static int __init ptp_ixp_init(void) +{ + if (!cpu_is_ixp46x()) + return -ENODEV; + + ixp_clock.regs = + (struct ixp46x_ts_regs __iomem *) IXP4XX_TIMESYNC_BASE_VIRT; + + ixp_clock.caps = ptp_ixp_caps; + + ixp_clock.ptp_clock = ptp_clock_register(&ixp_clock.caps); + + if (IS_ERR(ixp_clock.ptp_clock)) + return PTR_ERR(ixp_clock.ptp_clock); + + __raw_writel(DEFAULT_ADDEND, &ixp_clock.regs->addend); + __raw_writel(1, &ixp_clock.regs->trgt_lo); + __raw_writel(0, &ixp_clock.regs->trgt_hi); + __raw_writel(TTIPEND, &ixp_clock.regs->event); + + if (MASTER_IRQ != setup_interrupt(MASTER_GPIO)) { + pr_err("failed to setup gpio %d as irq\n", MASTER_GPIO); + goto no_master; + } + if (SLAVE_IRQ != setup_interrupt(SLAVE_GPIO)) { + pr_err("failed to setup gpio %d as irq\n", SLAVE_GPIO); + goto no_slave; + } + + return 0; +no_slave: + free_irq(MASTER_IRQ, &ixp_clock); +no_master: + ptp_clock_unregister(ixp_clock.ptp_clock); + return -ENODEV; +} + +module_init(ptp_ixp_init); +module_exit(ptp_ixp_exit); + +MODULE_AUTHOR("Richard Cochran <richard.cochran@omicron.at>"); +MODULE_DESCRIPTION("PTP clock using the IXP46X timer"); +MODULE_LICENSE("GPL"); |
