drivers/gpu/drm/nouveau/nvkm/subdev/i2c/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 "aux.h"
  26
  27 struct gm200_i2c_aux {
  28         struct nvkm_i2c_aux base;
  29         int ch;
  30 };
  31
  32 static void
  33 gm200_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), 0x00310000, 0x00000000);
  37 }
  38
  39 static int
  40 gm200_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 & 0x03010000);
  58
  59         /* set some magic, and wait up to 1ms for it to appear */
  60         nvkm_mask(device, 0x00d954 + (aux->ch * 0x50), 0x00300000, 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 & 0x03000000) != urep);
  71
  72         return 0;
  73 }
  74
  75 static int
  76 gm200_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_device *device = aux->base.pad->i2c->subdev.device;
  81         const u32 base = aux->ch * 0x50;
  82         u32 ctrl, stat, timeout, retries = 0;
  83         u32 xbuf[4] = {};
  84         int ret, i;
  85
  86         AUX_TRACE(&aux->base, "%d: %08x %d", type, addr, *size);
  87
  88         ret = gm200_i2c_aux_init(aux);
  89         if (ret < 0)
  90                 goto out;
  91
  92         stat = nvkm_rd32(device, 0x00d958 + base);
  93         if (!(stat & 0x10000000)) {
  94                 AUX_TRACE(&aux->base, "sink not detected");
  95                 ret = -ENXIO;
  96                 goto out;
  97         }
  98
  99         if (!(type & 1)) {
 100                 memcpy(xbuf, data, *size);
 101                 for (i = 0; i < 16; i += 4) {
 102                         AUX_TRACE(&aux->base, "wr %08x", xbuf[i / 4]);
 103                         nvkm_wr32(device, 0x00d930 + base + i, xbuf[i / 4]);
 104                 }
 105         }
 106
 107         ctrl  = nvkm_rd32(device, 0x00d954 + base);
 108         ctrl &= ~0x0001f1ff;
 109         ctrl |= type << 12;
 110         ctrl |= (*size ? (*size - 1) : 0x00000100);
 111         nvkm_wr32(device, 0x00d950 + base, addr);
 112
 113         /* (maybe) retry transaction a number of times on failure... */
 114         do {
 115                 /* reset, and delay a while if this is a retry */
 116                 nvkm_wr32(device, 0x00d954 + base, 0x80000000 | ctrl);
 117                 nvkm_wr32(device, 0x00d954 + base, 0x00000000 | ctrl);
 118                 if (retries)
 119                         udelay(400);
 120
 121                 /* transaction request, wait up to 2ms for it to complete */
 122                 nvkm_wr32(device, 0x00d954 + base, 0x00010000 | ctrl);
 123
 124                 timeout = 2000;
 125                 do {
 126                         ctrl = nvkm_rd32(device, 0x00d954 + base);
 127                         udelay(1);
 128                         if (!timeout--) {
 129                                 AUX_ERR(&aux->base, "timeout %08x", ctrl);
 130                                 ret = -EIO;
 131                                 goto out;
 132                         }
 133                 } while (ctrl & 0x00010000);
 134                 ret = 0;
 135
 136                 /* read status, and check if transaction completed ok */
 137                 stat = nvkm_mask(device, 0x00d958 + base, 0, 0);
 138                 if ((stat & 0x000f0000) == 0x00080000 ||
 139                     (stat & 0x000f0000) == 0x00020000)
 140                         ret = 1;
 141                 if ((stat & 0x00000100))
 142                         ret = -ETIMEDOUT;
 143                 if ((stat & 0x00000e00))
 144                         ret = -EIO;
 145
 146                 AUX_TRACE(&aux->base, "%02d %08x %08x", retries, ctrl, stat);
 147         } while (ret && retry && retries++ < 32);
 148
 149         if (type & 1) {
 150                 for (i = 0; i < 16; i += 4) {
 151                         xbuf[i / 4] = nvkm_rd32(device, 0x00d940 + base + i);
 152                         AUX_TRACE(&aux->base, "rd %08x", xbuf[i / 4]);
 153                 }
 154                 memcpy(data, xbuf, *size);
 155                 *size = stat & 0x0000001f;
 156         }
 157
 158 out:
 159         gm200_i2c_aux_fini(aux);
 160         return ret < 0 ? ret : (stat & 0x000f0000) >> 16;
 161 }
 162
 163 static const struct nvkm_i2c_aux_func
 164 gm200_i2c_aux_func = {
 165         .address_only = true,
 166         .xfer = gm200_i2c_aux_xfer,
 167 };
 168
 169 int
 170 gm200_i2c_aux_new(struct nvkm_i2c_pad *pad, int index, u8 drive,
 171                 struct nvkm_i2c_aux **paux)
 172 {
 173         struct gm200_i2c_aux *aux;
 174
 175         if (!(aux = kzalloc(sizeof(*aux), GFP_KERNEL)))
 176                 return -ENOMEM;
 177         *paux = &aux->base;
 178
 179         nvkm_i2c_aux_ctor(&gm200_i2c_aux_func, pad, index, &aux->base);
 180         aux->ch = drive;
 181         aux->base.intr = 1 << aux->ch;
 182         return 0;
 183 }