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1/*2 * Copyright 2012 Red Hat Inc.3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the "Software"),6 * to deal in the Software without restriction, including without limitation7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,8 * and/or sell copies of the Software, and to permit persons to whom the9 * Software is furnished to do so, subject to the following conditions:10 *11 * The above copyright notice and this permission notice shall be included in12 * all copies or substantial portions of the Software.13 *14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR20 * OTHER DEALINGS IN THE SOFTWARE.21 *22 * Authors: Ben Skeggs23 */24#include "priv.h"25#include "regsnv04.h"26 27static void28nv40_timer_init(struct nvkm_timer *tmr)29{30 struct nvkm_subdev *subdev = &tmr->subdev;31 struct nvkm_device *device = subdev->device;32 u32 f = 0; /*XXX: figure this out */33 u32 n, d;34 35 /* aim for 31.25MHz, which gives us nanosecond timestamps */36 d = 1000000 / 32;37 n = f;38 39 if (!f) {40 n = nvkm_rd32(device, NV04_PTIMER_NUMERATOR);41 d = nvkm_rd32(device, NV04_PTIMER_DENOMINATOR);42 if (!n || !d) {43 n = 1;44 d = 1;45 }46 nvkm_warn(subdev, "unknown input clock freq\n");47 }48 49 /* reduce ratio to acceptable values */50 while (((n % 5) == 0) && ((d % 5) == 0)) {51 n /= 5;52 d /= 5;53 }54 55 while (((n % 2) == 0) && ((d % 2) == 0)) {56 n /= 2;57 d /= 2;58 }59 60 while (n > 0xffff || d > 0xffff) {61 n >>= 1;62 d >>= 1;63 }64 65 nvkm_debug(subdev, "input frequency : %dHz\n", f);66 nvkm_debug(subdev, "numerator : %08x\n", n);67 nvkm_debug(subdev, "denominator : %08x\n", d);68 nvkm_debug(subdev, "timer frequency : %dHz\n", f * d / n);69 70 nvkm_wr32(device, NV04_PTIMER_NUMERATOR, n);71 nvkm_wr32(device, NV04_PTIMER_DENOMINATOR, d);72}73 74static const struct nvkm_timer_func75nv40_timer = {76 .init = nv40_timer_init,77 .intr = nv04_timer_intr,78 .read = nv04_timer_read,79 .time = nv04_timer_time,80 .alarm_init = nv04_timer_alarm_init,81 .alarm_fini = nv04_timer_alarm_fini,82};83 84int85nv40_timer_new(struct nvkm_device *device, enum nvkm_subdev_type type, int inst,86 struct nvkm_timer **ptmr)87{88 return nvkm_timer_new_(&nv40_timer, device, type, inst, ptmr);89}90