Add ARM Generic Timer driver.

Submitted by:	Ruslan Bukin <br@bsdpad.com>
This commit is contained in:
Aleksandr Rybalko 2013-06-29 12:27:50 +00:00
parent 83bee1a9ba
commit 48d5dbc7a2
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=252372

374
sys/arm/arm/generic_timer.c Normal file
View File

@ -0,0 +1,374 @@
/*-
* Copyright (c) 2011 The FreeBSD Foundation
* Copyright (c) 2013 Ruslan Bukin <br@bsdpad.com>
* All rights reserved.
*
* Based on mpcore_timer.c developed by Ben Gray <ben.r.gray@gmail.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the company nor the name of the author may be used to
* endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/**
* Cortex-A15 (and probably A7) Generic Timer
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/malloc.h>
#include <sys/rman.h>
#include <sys/timeet.h>
#include <sys/timetc.h>
#include <sys/watchdog.h>
#include <machine/bus.h>
#include <machine/cpu.h>
#include <machine/frame.h>
#include <machine/intr.h>
#include <dev/fdt/fdt_common.h>
#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <machine/bus.h>
#include <machine/fdt.h>
#define GENERIC_TIMER_CTRL_ENABLE (1 << 0)
#define GENERIC_TIMER_CTRL_INT_MASK (1 << 1)
#define GENERIC_TIMER_CTRL_INT_STAT (1 << 2)
#define GENERIC_TIMER_REG_CTRL 0
#define GENERIC_TIMER_REG_TVAL 1
#define CNTPSIRQ 29
struct arm_tmr_softc {
struct resource *irq_res;
uint32_t clkfreq;
struct eventtimer et;
};
static struct arm_tmr_softc *arm_tmr_sc = NULL;
static timecounter_get_t arm_tmr_get_timecount;
static struct timecounter arm_tmr_timecount = {
.tc_name = "ARM MPCore Timecounter",
.tc_get_timecount = arm_tmr_get_timecount,
.tc_poll_pps = NULL,
.tc_counter_mask = ~0u,
.tc_frequency = 0,
.tc_quality = 1000,
};
static inline int
get_freq(void)
{
uint32_t val;
__asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
return (val);
}
static inline int
set_freq(uint32_t val)
{
__asm volatile("mcr p15, 0, %[val], c14, c0, 0" : :
[val] "r" (val));
isb();
return (val);
}
static inline long
get_cntpct(void)
{
uint64_t val;
__asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (val));
return (val);
}
static inline int
set_ctrl(uint32_t val)
{
__asm volatile("mcr p15, 0, %[val], c14, c2, 1" : :
[val] "r" (val));
isb();
return (0);
}
static inline int
set_tval(uint32_t val)
{
__asm volatile("mcr p15, 0, %[val], c14, c2, 0" : :
[val] "r" (val));
isb();
return (0);
}
static inline int
get_ctrl(void)
{
uint32_t val;
__asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val));
return (val);
}
static inline int
get_tval(void)
{
uint32_t val;
__asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
return (val);
}
static inline void
disable_user_access(void)
{
uint32_t cntkctl;
__asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl));
cntkctl &= ~((3 << 8) | (7 << 0));
__asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl));
isb();
}
static unsigned
arm_tmr_get_timecount(struct timecounter *tc)
{
return (get_cntpct());
}
static int
arm_tmr_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
{
struct arm_tmr_softc *sc;
int counts, ctrl;
sc = (struct arm_tmr_softc *)et->et_priv;
if (first != 0) {
counts = ((uint32_t)et->et_frequency * first) >> 32;
ctrl = get_ctrl();
ctrl &= ~GENERIC_TIMER_CTRL_INT_MASK;
ctrl |= GENERIC_TIMER_CTRL_ENABLE;
set_tval(counts);
set_ctrl(ctrl);
return (0);
}
return (EINVAL);
}
static int
arm_tmr_stop(struct eventtimer *et)
{
int ctrl;
ctrl = get_ctrl();
ctrl &= GENERIC_TIMER_CTRL_ENABLE;
set_ctrl(ctrl);
return (0);
}
static int
arm_tmr_intr(void *arg)
{
struct arm_tmr_softc *sc;
int ctrl;
sc = (struct arm_tmr_softc *)arg;
ctrl = get_ctrl();
if (ctrl & GENERIC_TIMER_CTRL_INT_STAT) {
ctrl |= GENERIC_TIMER_CTRL_INT_MASK;
set_ctrl(ctrl);
}
if (sc->et.et_active)
sc->et.et_event_cb(&sc->et, sc->et.et_arg);
return (FILTER_HANDLED);
}
static int
arm_tmr_probe(device_t dev)
{
if (!ofw_bus_is_compatible(dev, "arm,armv7-timer"))
return (ENXIO);
device_set_desc(dev, "ARMv7 Generic Timer");
return (BUS_PROBE_DEFAULT);
}
static int
arm_tmr_attach(device_t dev)
{
struct arm_tmr_softc *sc;
phandle_t node;
pcell_t clock;
void *ihl;
int rid;
int error;
sc = device_get_softc(dev);
if (arm_tmr_sc)
return (ENXIO);
/* Get the base clock frequency */
node = ofw_bus_get_node(dev);
error = OF_getprop(node, "clock-frequency", &clock, sizeof(clock));
if (error <= 0) {
device_printf(dev, "missing clock-frequency "
"attribute in FDT\n");
return (ENXIO);
}
sc->clkfreq = fdt32_to_cpu(clock);
rid = 0;
sc->irq_res = bus_alloc_resource(dev, SYS_RES_IRQ, &rid,
CNTPSIRQ, CNTPSIRQ, 1, RF_SHAREABLE | RF_ACTIVE);
arm_tmr_sc = sc;
/* Setup and enable the timer */
if (bus_setup_intr(dev, sc->irq_res, INTR_TYPE_CLK, arm_tmr_intr,
NULL, sc, &ihl) != 0) {
bus_release_resource(dev, SYS_RES_IRQ, rid, sc->irq_res);
device_printf(dev, "Unable to setup the CLK irq handler.\n");
return (ENXIO);
}
set_freq(sc->clkfreq);
disable_user_access();
arm_tmr_timecount.tc_frequency = sc->clkfreq;
tc_init(&arm_tmr_timecount);
sc->et.et_name = "ARM MPCore Eventtimer";
sc->et.et_flags = ET_FLAGS_ONESHOT | ET_FLAGS_PERCPU;
sc->et.et_quality = 1000;
sc->et.et_frequency = sc->clkfreq;
sc->et.et_min_period = (0x00000002LLU << 32) / sc->et.et_frequency;
sc->et.et_max_period = (0xfffffffeLLU << 32) / sc->et.et_frequency;
sc->et.et_start = arm_tmr_start;
sc->et.et_stop = arm_tmr_stop;
sc->et.et_priv = sc;
et_register(&sc->et);
return (0);
}
static device_method_t arm_tmr_methods[] = {
DEVMETHOD(device_probe, arm_tmr_probe),
DEVMETHOD(device_attach, arm_tmr_attach),
{ 0, 0 }
};
static driver_t arm_tmr_driver = {
"generic_timer",
arm_tmr_methods,
sizeof(struct arm_tmr_softc),
};
static devclass_t arm_tmr_devclass;
DRIVER_MODULE(timer, simplebus, arm_tmr_driver, arm_tmr_devclass, 0, 0);
void
cpu_initclocks(void)
{
if (PCPU_GET(cpuid) == 0)
cpu_initclocks_bsp();
else
cpu_initclocks_ap();
}
void
DELAY(int usec)
{
int32_t counts, counts_per_usec;
uint32_t first, last;
/*
* Check the timers are setup, if not just
* use a for loop for the meantime
*/
if (arm_tmr_sc == NULL) {
for (; usec > 0; usec--)
for (counts = 200; counts > 0; counts--)
/*
* Prevent gcc from optimizing
* out the loop
*/
cpufunc_nullop();
return;
}
/* Get the number of times to count */
counts_per_usec = ((arm_tmr_timecount.tc_frequency / 1000000) + 1);
/*
* Clamp the timeout at a maximum value (about 32 seconds with
* a 66MHz clock). *Nobody* should be delay()ing for anywhere
* near that length of time and if they are, they should be hung
* out to dry.
*/
if (usec >= (0x80000000U / counts_per_usec))
counts = (0x80000000U / counts_per_usec) - 1;
else
counts = usec * counts_per_usec;
first = get_cntpct();
while (counts > 0) {
last = get_cntpct();
counts -= (int32_t)(last - first);
first = last;
}
}