auxgm200.c

  1/*
  2 * Copyright 2015 Red Hat Inc.
  3 *
  4 * Permission is hereby granted, free of charge, to any person obtaining a
  5 * copy of this software and associated documentation files (the "Software"),
  6 * to deal in the Software without restriction, including without limitation
  7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  8 * and/or sell copies of the Software, and to permit persons to whom the
  9 * Software is furnished to do so, subject to the following conditions:
 10 *
 11 * The above copyright notice and this permission notice shall be included in
 12 * all copies or substantial busions of the Software.
 13 *
 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 18 * 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 OR
 20 * OTHER DEALINGS IN THE SOFTWARE.
 21 *
 22 * Authors: Ben Skeggs <bskeggs@redhat.com>
 23 */
 24#define gm200_i2c_aux(p) container_of((p), struct gm200_i2c_aux, base)
 25#include "auxch.h"
 26
 27struct gm200_i2c_aux {
 28	struct nvkm_i2c_aux base;
 29	int ch;
 30};
 31
 32static void
 33gm200_i2c_aux_fini(struct gm200_i2c_aux *aux)
 34{
 35	struct nvkm_device *device = aux->base.pad->i2c->subdev.device;
 36	nvkm_mask(device, 0x00d954 + (aux->ch * 0x50), 0x00710000, 0x00000000);
 37}
 38
 39static int
 40gm200_i2c_aux_init(struct gm200_i2c_aux *aux)
 41{
 42	struct nvkm_device *device = aux->base.pad->i2c->subdev.device;
 43	const u32 unksel = 1; /* nfi which to use, or if it matters.. */
 44	const u32 ureq = unksel ? 0x00100000 : 0x00200000;
 45	const u32 urep = unksel ? 0x01000000 : 0x02000000;
 46	u32 ctrl, timeout;
 47
 48	/* wait up to 1ms for any previous transaction to be done... */
 49	timeout = 1000;
 50	do {
 51		ctrl = nvkm_rd32(device, 0x00d954 + (aux->ch * 0x50));
 52		udelay(1);
 53		if (!timeout--) {
 54			AUX_ERR(&aux->base, "begin idle timeout %08x", ctrl);
 55			return -EBUSY;
 56		}
 57	} while (ctrl & 0x07010000);
 58
 59	/* set some magic, and wait up to 1ms for it to appear */
 60	nvkm_mask(device, 0x00d954 + (aux->ch * 0x50), 0x00700000, ureq);
 61	timeout = 1000;
 62	do {
 63		ctrl = nvkm_rd32(device, 0x00d954 + (aux->ch * 0x50));
 64		udelay(1);
 65		if (!timeout--) {
 66			AUX_ERR(&aux->base, "magic wait %08x", ctrl);
 67			gm200_i2c_aux_fini(aux);
 68			return -EBUSY;
 69		}
 70	} while ((ctrl & 0x07000000) != urep);
 71
 72	return 0;
 73}
 74
 75static int
 76gm200_i2c_aux_xfer(struct nvkm_i2c_aux *obj, bool retry,
 77		   u8 type, u32 addr, u8 *data, u8 *size)
 78{
 79	struct gm200_i2c_aux *aux = gm200_i2c_aux(obj);
 80	struct nvkm_i2c *i2c = aux->base.pad->i2c;
 81	struct nvkm_device *device = i2c->subdev.device;
 82	const u32 base = aux->ch * 0x50;
 83	u32 ctrl, stat, timeout, retries = 0;
 84	u32 xbuf[4] = {};
 85	int ret, i;
 86
 87	AUX_TRACE(&aux->base, "%d: %08x %d", type, addr, *size);
 88
 89	ret = gm200_i2c_aux_init(aux);
 90	if (ret < 0)
 91		goto out;
 92
 93	stat = nvkm_rd32(device, 0x00d958 + base);
 94	if (!(stat & 0x10000000)) {
 95		AUX_TRACE(&aux->base, "sink not detected");
 96		ret = -ENXIO;
 97		goto out;
 98	}
 99
100	nvkm_i2c_aux_autodpcd(i2c, aux->ch, false);
101
102	if (!(type & 1)) {
103		memcpy(xbuf, data, *size);
104		for (i = 0; i < 16; i += 4) {
105			AUX_TRACE(&aux->base, "wr %08x", xbuf[i / 4]);
106			nvkm_wr32(device, 0x00d930 + base + i, xbuf[i / 4]);
107		}
108	}
109
110	ctrl  = nvkm_rd32(device, 0x00d954 + base);
111	ctrl &= ~0x0001f1ff;
112	ctrl |= type << 12;
113	ctrl |= (*size ? (*size - 1) : 0x00000100);
114	nvkm_wr32(device, 0x00d950 + base, addr);
115
116	/* (maybe) retry transaction a number of times on failure... */
117	do {
118		/* reset, and delay a while if this is a retry */
119		nvkm_wr32(device, 0x00d954 + base, 0x80000000 | ctrl);
120		nvkm_wr32(device, 0x00d954 + base, 0x00000000 | ctrl);
121		if (retries)
122			udelay(400);
123
124		/* transaction request, wait up to 2ms for it to complete */
125		nvkm_wr32(device, 0x00d954 + base, 0x00010000 | ctrl);
126
127		timeout = 2000;
128		do {
129			ctrl = nvkm_rd32(device, 0x00d954 + base);
130			udelay(1);
131			if (!timeout--) {
132				AUX_ERR(&aux->base, "timeout %08x", ctrl);
133				ret = -EIO;
134				goto out_err;
135			}
136		} while (ctrl & 0x00010000);
137		ret = 0;
138
139		/* read status, and check if transaction completed ok */
140		stat = nvkm_mask(device, 0x00d958 + base, 0, 0);
141		if ((stat & 0x000f0000) == 0x00080000 ||
142		    (stat & 0x000f0000) == 0x00020000)
143			ret = 1;
144		if ((stat & 0x00000100))
145			ret = -ETIMEDOUT;
146		if ((stat & 0x00000e00))
147			ret = -EIO;
148
149		AUX_TRACE(&aux->base, "%02d %08x %08x", retries, ctrl, stat);
150	} while (ret && retry && retries++ < 32);
151
152	if (type & 1) {
153		for (i = 0; i < 16; i += 4) {
154			xbuf[i / 4] = nvkm_rd32(device, 0x00d940 + base + i);
155			AUX_TRACE(&aux->base, "rd %08x", xbuf[i / 4]);
156		}
157		memcpy(data, xbuf, *size);
158		*size = stat & 0x0000001f;
159	}
160
161out_err:
162	nvkm_i2c_aux_autodpcd(i2c, aux->ch, true);
163out:
164	gm200_i2c_aux_fini(aux);
165	return ret < 0 ? ret : (stat & 0x000f0000) >> 16;
166}
167
168static const struct nvkm_i2c_aux_func
169gm200_i2c_aux_func = {
170	.address_only = true,
171	.xfer = gm200_i2c_aux_xfer,
172};
173
174int
175gm200_i2c_aux_new(struct nvkm_i2c_pad *pad, int index, u8 drive,
176		struct nvkm_i2c_aux **paux)
177{
178	struct gm200_i2c_aux *aux;
179
180	if (!(aux = kzalloc(sizeof(*aux), GFP_KERNEL)))
181		return -ENOMEM;
182	*paux = &aux->base;
183
184	nvkm_i2c_aux_ctor(&gm200_i2c_aux_func, pad, index, &aux->base);
185	aux->ch = drive;
186	aux->base.intr = 1 << aux->ch;
187	return 0;
188}