linux/drivers/ptp/ptp_ixp46x.c
Thomas Gleixner 74ba9207e1 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 441 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520071858.739733335@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:36:45 +02:00

329 lines
6.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* PTP 1588 clock using the IXP46X
*
* Copyright (C) 2010 OMICRON electronics GmbH
*/
#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(&regs->systime_lo);
hi = __raw_readl(&regs->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, &regs->systime_lo);
__raw_writel(hi, &regs->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(&regs->event);
if (val & TSER_SNS) {
ack |= TSER_SNS;
if (ixp_clock->exts0_enabled) {
hi = __raw_readl(&regs->asms_hi);
lo = __raw_readl(&regs->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(&regs->amms_hi);
lo = __raw_readl(&regs->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, &regs->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, &regs->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(&register_lock, flags);
now = ixp_systime_read(regs);
now += delta;
ixp_systime_write(regs, now);
spin_unlock_irqrestore(&register_lock, flags);
return 0;
}
static int ptp_ixp_gettime(struct ptp_clock_info *ptp, struct timespec64 *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;
spin_lock_irqsave(&register_lock, flags);
ns = ixp_systime_read(regs);
spin_unlock_irqrestore(&register_lock, flags);
*ts = ns_to_timespec64(ns);
return 0;
}
static int ptp_ixp_settime(struct ptp_clock_info *ptp,
const struct timespec64 *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 = timespec64_to_ns(ts);
spin_lock_irqsave(&register_lock, flags);
ixp_systime_write(regs, ns);
spin_unlock_irqrestore(&register_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 const struct ptp_clock_info ptp_ixp_caps = {
.owner = THIS_MODULE,
.name = "IXP46X timer",
.max_adj = 66666655,
.n_ext_ts = N_EXT_TS,
.n_pins = 0,
.pps = 0,
.adjfreq = ptp_ixp_adjfreq,
.adjtime = ptp_ixp_adjtime,
.gettime64 = ptp_ixp_gettime,
.settime64 = ptp_ixp_settime,
.enable = ptp_ixp_enable,
};
/* module operations */
static struct ixp_clock ixp_clock;
static int setup_interrupt(int gpio)
{
int irq;
int err;
err = gpio_request(gpio, "ixp4-ptp");
if (err)
return err;
err = gpio_direction_input(gpio);
if (err)
return err;
irq = gpio_to_irq(gpio);
if (irq < 0)
return irq;
err = irq_set_irq_type(irq, IRQF_TRIGGER_FALLING);
if (err) {
pr_err("cannot set trigger type for irq %d\n", irq);
return err;
}
err = request_irq(irq, isr, 0, DRIVER, &ixp_clock);
if (err) {
pr_err("request_irq failed for irq %d\n", irq);
return err;
}
return irq;
}
static void __exit ptp_ixp_exit(void)
{
free_irq(MASTER_IRQ, &ixp_clock);
free_irq(SLAVE_IRQ, &ixp_clock);
ixp46x_phc_index = -1;
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, NULL);
if (IS_ERR(ixp_clock.ptp_clock))
return PTR_ERR(ixp_clock.ptp_clock);
ixp46x_phc_index = ptp_clock_index(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 <richardcochran@gmail.com>");
MODULE_DESCRIPTION("PTP clock using the IXP46X timer");
MODULE_LICENSE("GPL");