linuxdebug/drivers/gpu/drm/nouveau/nvkm/subdev/timer/nv41.c

87 lines
2.5 KiB
C

/*
* Copyright 2012 Red Hat Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors: Ben Skeggs
*/
#include "priv.h"
#include "regsnv04.h"
static void
nv41_timer_init(struct nvkm_timer *tmr)
{
struct nvkm_subdev *subdev = &tmr->subdev;
struct nvkm_device *device = subdev->device;
u32 f = device->crystal;
u32 m = 1, n, d;
/* aim for 31.25MHz, which gives us nanosecond timestamps */
d = 1000000 / 32;
n = f;
while (n < (d * 2)) {
n += (n / m);
m++;
}
/* reduce ratio to acceptable values */
while (((n % 5) == 0) && ((d % 5) == 0)) {
n /= 5;
d /= 5;
}
while (((n % 2) == 0) && ((d % 2) == 0)) {
n /= 2;
d /= 2;
}
while (n > 0xffff || d > 0xffff) {
n >>= 1;
d >>= 1;
}
nvkm_debug(subdev, "input frequency : %dHz\n", f);
nvkm_debug(subdev, "input multiplier: %d\n", m);
nvkm_debug(subdev, "numerator : %08x\n", n);
nvkm_debug(subdev, "denominator : %08x\n", d);
nvkm_debug(subdev, "timer frequency : %dHz\n", (f * m) * d / n);
nvkm_wr32(device, 0x009220, m - 1);
nvkm_wr32(device, NV04_PTIMER_NUMERATOR, n);
nvkm_wr32(device, NV04_PTIMER_DENOMINATOR, d);
}
static const struct nvkm_timer_func
nv41_timer = {
.init = nv41_timer_init,
.intr = nv04_timer_intr,
.read = nv04_timer_read,
.time = nv04_timer_time,
.alarm_init = nv04_timer_alarm_init,
.alarm_fini = nv04_timer_alarm_fini,
};
int
nv41_timer_new(struct nvkm_device *device, enum nvkm_subdev_type type, int inst,
struct nvkm_timer **ptmr)
{
return nvkm_timer_new_(&nv41_timer, device, type, inst, ptmr);
}