drivers/hwtracing/intel_th/sth.c

   1 /*
   2  * Intel(R) Trace Hub Software Trace Hub support
   3  *
   4  * Copyright (C) 2014-2015 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  */
  15
  16 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  17
  18 #include <linux/types.h>
  19 #include <linux/module.h>
  20 #include <linux/device.h>
  21 #include <linux/io.h>
  22 #include <linux/mm.h>
  23 #include <linux/slab.h>
  24 #include <linux/stm.h>
  25
  26 #include "intel_th.h"
  27 #include "sth.h"
  28
  29 struct sth_device {
  30         void __iomem    *base;
  31         void __iomem    *channels;
  32         phys_addr_t     channels_phys;
  33         struct device   *dev;
  34         struct stm_data stm;
  35         unsigned int    sw_nmasters;
  36 };
  37
  38 static struct intel_th_channel __iomem *
  39 sth_channel(struct sth_device *sth, unsigned int master, unsigned int channel)
  40 {
  41         struct intel_th_channel __iomem *sw_map = sth->channels;
  42
  43         return &sw_map[(master - sth->stm.sw_start) * sth->stm.sw_nchannels +
  44                        channel];
  45 }
  46
  47 static void sth_iowrite(void __iomem *dest, const unsigned char *payload,
  48                         unsigned int size)
  49 {
  50         switch (size) {
  51 #ifdef CONFIG_64BIT
  52         case 8:
  53                 writeq_relaxed(*(u64 *)payload, dest);
  54                 break;
  55 #endif
  56         case 4:
  57                 writel_relaxed(*(u32 *)payload, dest);
  58                 break;
  59         case 2:
  60                 writew_relaxed(*(u16 *)payload, dest);
  61                 break;
  62         case 1:
  63                 writeb_relaxed(*(u8 *)payload, dest);
  64                 break;
  65         default:
  66                 break;
  67         }
  68 }
  69
  70 static ssize_t sth_stm_packet(struct stm_data *stm_data, unsigned int master,
  71                               unsigned int channel, unsigned int packet,
  72                               unsigned int flags, unsigned int size,
  73                               const unsigned char *payload)
  74 {
  75         struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
  76         struct intel_th_channel __iomem *out =
  77                 sth_channel(sth, master, channel);
  78         u64 __iomem *outp = &out->Dn;
  79         unsigned long reg = REG_STH_TRIG;
  80
  81 #ifndef CONFIG_64BIT
  82         if (size > 4)
  83                 size = 4;
  84 #endif
  85
  86         size = rounddown_pow_of_two(size);
  87
  88         switch (packet) {
  89         /* Global packets (GERR, XSYNC, TRIG) are sent with register writes */
  90         case STP_PACKET_GERR:
  91                 reg += 4;
  92         case STP_PACKET_XSYNC:
  93                 reg += 8;
  94         case STP_PACKET_TRIG:
  95                 if (flags & STP_PACKET_TIMESTAMPED)
  96                         reg += 4;
  97                 writeb_relaxed(*payload, sth->base + reg);
  98                 break;
  99
 100         case STP_PACKET_MERR:
 101                 if (size > 4)
 102                         size = 4;
 103
 104                 sth_iowrite(&out->MERR, payload, size);
 105                 break;
 106
 107         case STP_PACKET_FLAG:
 108                 if (flags & STP_PACKET_TIMESTAMPED)
 109                         outp = (u64 __iomem *)&out->FLAG_TS;
 110                 else
 111                         outp = (u64 __iomem *)&out->FLAG;
 112
 113                 size = 0;
 114                 writeb_relaxed(0, outp);
 115                 break;
 116
 117         case STP_PACKET_USER:
 118                 if (flags & STP_PACKET_TIMESTAMPED)
 119                         outp = &out->USER_TS;
 120                 else
 121                         outp = &out->USER;
 122                 sth_iowrite(outp, payload, size);
 123                 break;
 124
 125         case STP_PACKET_DATA:
 126                 outp = &out->Dn;
 127
 128                 if (flags & STP_PACKET_TIMESTAMPED)
 129                         outp += 2;
 130                 if (flags & STP_PACKET_MARKED)
 131                         outp++;
 132
 133                 sth_iowrite(outp, payload, size);
 134                 break;
 135         default:
 136                 return -ENOTSUPP;
 137         }
 138
 139         return size;
 140 }
 141
 142 static phys_addr_t
 143 sth_stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
 144                   unsigned int channel, unsigned int nr_chans)
 145 {
 146         struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
 147         phys_addr_t addr;
 148
 149         master -= sth->stm.sw_start;
 150         addr = sth->channels_phys + (master * sth->stm.sw_nchannels + channel) *
 151                 sizeof(struct intel_th_channel);
 152
 153         if (offset_in_page(addr) ||
 154             offset_in_page(nr_chans * sizeof(struct intel_th_channel)))
 155                 return 0;
 156
 157         return addr;
 158 }
 159
 160 static int sth_stm_link(struct stm_data *stm_data, unsigned int master,
 161                          unsigned int channel)
 162 {
 163         struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
 164
 165         intel_th_set_output(to_intel_th_device(sth->dev), master);
 166
 167         return 0;
 168 }
 169
 170 static int intel_th_sw_init(struct sth_device *sth)
 171 {
 172         u32 reg;
 173
 174         reg = ioread32(sth->base + REG_STH_STHCAP1);
 175         sth->stm.sw_nchannels = reg & 0xff;
 176
 177         reg = ioread32(sth->base + REG_STH_STHCAP0);
 178         sth->stm.sw_start = reg & 0xffff;
 179         sth->stm.sw_end = reg >> 16;
 180
 181         sth->sw_nmasters = sth->stm.sw_end - sth->stm.sw_start;
 182         dev_dbg(sth->dev, "sw_start: %x sw_end: %x masters: %x nchannels: %x\n",
 183                 sth->stm.sw_start, sth->stm.sw_end, sth->sw_nmasters,
 184                 sth->stm.sw_nchannels);
 185
 186         return 0;
 187 }
 188
 189 static int intel_th_sth_probe(struct intel_th_device *thdev)
 190 {
 191         struct device *dev = &thdev->dev;
 192         struct sth_device *sth;
 193         struct resource *res;
 194         void __iomem *base, *channels;
 195         int err;
 196
 197         res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
 198         if (!res)
 199                 return -ENODEV;
 200
 201         base = devm_ioremap(dev, res->start, resource_size(res));
 202         if (!base)
 203                 return -ENOMEM;
 204
 205         res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 1);
 206         if (!res)
 207                 return -ENODEV;
 208
 209         channels = devm_ioremap(dev, res->start, resource_size(res));
 210         if (!channels)
 211                 return -ENOMEM;
 212
 213         sth = devm_kzalloc(dev, sizeof(*sth), GFP_KERNEL);
 214         if (!sth)
 215                 return -ENOMEM;
 216
 217         sth->dev = dev;
 218         sth->base = base;
 219         sth->channels = channels;
 220         sth->channels_phys = res->start;
 221         sth->stm.name = dev_name(dev);
 222         sth->stm.packet = sth_stm_packet;
 223         sth->stm.mmio_addr = sth_stm_mmio_addr;
 224         sth->stm.sw_mmiosz = sizeof(struct intel_th_channel);
 225         sth->stm.link = sth_stm_link;
 226
 227         err = intel_th_sw_init(sth);
 228         if (err)
 229                 return err;
 230
 231         err = stm_register_device(dev, &sth->stm, THIS_MODULE);
 232         if (err) {
 233                 dev_err(dev, "stm_register_device failed\n");
 234                 return err;
 235         }
 236
 237         dev_set_drvdata(dev, sth);
 238
 239         return 0;
 240 }
 241
 242 static void intel_th_sth_remove(struct intel_th_device *thdev)
 243 {
 244         struct sth_device *sth = dev_get_drvdata(&thdev->dev);
 245
 246         stm_unregister_device(&sth->stm);
 247 }
 248
 249 static struct intel_th_driver intel_th_sth_driver = {
 250         .probe  = intel_th_sth_probe,
 251         .remove = intel_th_sth_remove,
 252         .driver = {
 253                 .name   = "sth",
 254                 .owner  = THIS_MODULE,
 255         },
 256 };
 257
 258 module_driver(intel_th_sth_driver,
 259               intel_th_driver_register,
 260               intel_th_driver_unregister);
 261
 262 MODULE_LICENSE("GPL v2");
 263 MODULE_DESCRIPTION("Intel(R) Trace Hub Software Trace Hub driver");
 264 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@intel.com>");