cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

nouveau_led.c (3908B)

      1/*
      2 * Copyright (C) 2016 Martin Peres
      3 *
      4 * Permission is hereby granted, free of charge, to any person obtaining
      5 * a copy of this software and associated documentation files (the
      6 * "Software"), to deal in the Software without restriction, including
      7 * without limitation the rights to use, copy, modify, merge, publish,
      8 * distribute, sublicense, and/or sell copies of the Software, and to
      9 * permit persons to whom the Software is furnished to do so, subject to
     10 * the following conditions:
     11 *
     12 * The above copyright notice and this permission notice (including the
     13 * next paragraph) shall be included in all copies or substantial
     14 * portions of the Software.
     15 *
     16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     17 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
     19 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
     20 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
     21 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
     22 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     23 *
     24 */
     25
     26/*
     27 * Authors:
     28 *  Martin Peres <martin.peres@free.fr>
     29 */
     30
     31#include <linux/leds.h>
     32
     33#include "nouveau_led.h"
     34#include <nvkm/subdev/gpio.h>
     35
     36static enum led_brightness
     37nouveau_led_get_brightness(struct led_classdev *led)
     38{
     39	struct drm_device *drm_dev = container_of(led, struct nouveau_led, led)->dev;
     40	struct nouveau_drm *drm = nouveau_drm(drm_dev);
     41	struct nvif_object *device = &drm->client.device.object;
     42	u32 div, duty;
     43
     44	div =  nvif_rd32(device, 0x61c880) & 0x00ffffff;
     45	duty = nvif_rd32(device, 0x61c884) & 0x00ffffff;
     46
     47	if (div > 0)
     48		return duty * LED_FULL / div;
     49	else
     50		return 0;
     51}
     52
     53static void
     54nouveau_led_set_brightness(struct led_classdev *led, enum led_brightness value)
     55{
     56	struct drm_device *drm_dev = container_of(led, struct nouveau_led, led)->dev;
     57	struct nouveau_drm *drm = nouveau_drm(drm_dev);
     58	struct nvif_object *device = &drm->client.device.object;
     59
     60	u32 input_clk = 27e6; /* PDISPLAY.SOR[1].PWM is connected to the crystal */
     61	u32 freq = 100; /* this is what nvidia uses and it should be good-enough */
     62	u32 div, duty;
     63
     64	div = input_clk / freq;
     65	duty = value * div / LED_FULL;
     66
     67	/* for now, this is safe to directly poke those registers because:
     68	 *  - A: nvidia never puts the logo led to any other PWM controler
     69	 *       than PDISPLAY.SOR[1].PWM.
     70	 *  - B: nouveau does not touch these registers anywhere else
     71	 */
     72	nvif_wr32(device, 0x61c880, div);
     73	nvif_wr32(device, 0x61c884, 0xc0000000 | duty);
     74}
     75
     76
     77int
     78nouveau_led_init(struct drm_device *dev)
     79{
     80	struct nouveau_drm *drm = nouveau_drm(dev);
     81	struct nvkm_gpio *gpio = nvxx_gpio(&drm->client.device);
     82	struct dcb_gpio_func logo_led;
     83	int ret;
     84
     85	if (!gpio)
     86		return 0;
     87
     88	/* check that there is a GPIO controlling the logo LED */
     89	if (nvkm_gpio_find(gpio, 0, DCB_GPIO_LOGO_LED_PWM, 0xff, &logo_led))
     90		return 0;
     91
     92	drm->led = kzalloc(sizeof(*drm->led), GFP_KERNEL);
     93	if (!drm->led)
     94		return -ENOMEM;
     95	drm->led->dev = dev;
     96
     97	drm->led->led.name = "nvidia-logo";
     98	drm->led->led.max_brightness = 255;
     99	drm->led->led.brightness_get = nouveau_led_get_brightness;
    100	drm->led->led.brightness_set = nouveau_led_set_brightness;
    101
    102	ret = led_classdev_register(dev->dev, &drm->led->led);
    103	if (ret) {
    104		kfree(drm->led);
    105		drm->led = NULL;
    106		return ret;
    107	}
    108
    109	return 0;
    110}
    111
    112void
    113nouveau_led_suspend(struct drm_device *dev)
    114{
    115	struct nouveau_drm *drm = nouveau_drm(dev);
    116
    117	if (drm->led)
    118		led_classdev_suspend(&drm->led->led);
    119}
    120
    121void
    122nouveau_led_resume(struct drm_device *dev)
    123{
    124	struct nouveau_drm *drm = nouveau_drm(dev);
    125
    126	if (drm->led)
    127		led_classdev_resume(&drm->led->led);
    128}
    129
    130void
    131nouveau_led_fini(struct drm_device *dev)
    132{
    133	struct nouveau_drm *drm = nouveau_drm(dev);
    134
    135	if (drm->led) {
    136		led_classdev_unregister(&drm->led->led);
    137		kfree(drm->led);
    138		drm->led = NULL;
    139	}
    140}