1/* $NetBSD: nouveau_nvkm_subdev_timer_nv41.c,v 1.3 2021/12/18 23:45:42 riastradh Exp $ */ 2 3/* 4 * Copyright 2012 Red Hat Inc. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the "Software"), 8 * to deal in the Software without restriction, including without limitation 9 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 10 * and/or sell copies of the Software, and to permit persons to whom the 11 * Software is furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 22 * OTHER DEALINGS IN THE SOFTWARE. 23 * 24 * Authors: Ben Skeggs 25 */ 26#include <sys/cdefs.h> 27__KERNEL_RCSID(0, "$NetBSD: nouveau_nvkm_subdev_timer_nv41.c,v 1.3 2021/12/18 23:45:42 riastradh Exp $"); 28 29#include "priv.h" 30#include "regsnv04.h" 31 32static void 33nv41_timer_init(struct nvkm_timer *tmr) 34{ 35 struct nvkm_subdev *subdev = &tmr->subdev; 36 struct nvkm_device *device = subdev->device; 37 u32 f = device->crystal; 38 u32 m = 1, n, d; 39 40 /* aim for 31.25MHz, which gives us nanosecond timestamps */ 41 d = 1000000 / 32; 42 n = f; 43 44 while (n < (d * 2)) { 45 n += (n / m); 46 m++; 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, "input multiplier: %d\n", m); 67 nvkm_debug(subdev, "numerator : %08x\n", n); 68 nvkm_debug(subdev, "denominator : %08x\n", d); 69 nvkm_debug(subdev, "timer frequency : %dHz\n", (f * m) * d / n); 70 71 nvkm_wr32(device, 0x009220, m - 1); 72 nvkm_wr32(device, NV04_PTIMER_NUMERATOR, n); 73 nvkm_wr32(device, NV04_PTIMER_DENOMINATOR, d); 74} 75 76static const struct nvkm_timer_func 77nv41_timer = { 78 .init = nv41_timer_init, 79 .intr = nv04_timer_intr, 80 .read = nv04_timer_read, 81 .time = nv04_timer_time, 82 .alarm_init = nv04_timer_alarm_init, 83 .alarm_fini = nv04_timer_alarm_fini, 84}; 85 86int 87nv41_timer_new(struct nvkm_device *device, int index, struct nvkm_timer **ptmr) 88{ 89 return nvkm_timer_new_(&nv41_timer, device, index, ptmr); 90} 91