drivers/hwtracing/intel_th/sth.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Intel(R) Trace Hub Software Trace Hub support
   4  *
   5  * Copyright (C) 2014-2015 Intel Corporation.
   6  */
   7
   8 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/types.h>
  11 #include <linux/module.h>
  12 #include <linux/device.h>
  13 #include <linux/io.h>
  14 #include <linux/mm.h>
  15 #include <linux/slab.h>
  16 #include <linux/stm.h>
  17
  18 #include "intel_th.h"
  19 #include "sth.h"
  20
  21 struct sth_device {
  22         void __iomem    *base;
  23         void __iomem    *channels;
  24         phys_addr_t     channels_phys;
  25         struct device   *dev;
  26         struct stm_data stm;
  27         unsigned int    sw_nmasters;
  28 };
  29
  30 static struct intel_th_channel __iomem *
  31 sth_channel(struct sth_device *sth, unsigned int master, unsigned int channel)
  32 {
  33         struct intel_th_channel __iomem *sw_map = sth->channels;
  34
  35         return &sw_map[(master - sth->stm.sw_start) * sth->stm.sw_nchannels +
  36                        channel];
  37 }
  38
  39 static void sth_iowrite(void __iomem *dest, const unsigned char *payload,
  40                         unsigned int size)
  41 {
  42         switch (size) {
  43 #ifdef CONFIG_64BIT
  44         case 8:
  45                 writeq_relaxed(*(u64 *)payload, dest);
  46                 break;
  47 #endif
  48         case 4:
  49                 writel_relaxed(*(u32 *)payload, dest);
  50                 break;
  51         case 2:
  52                 writew_relaxed(*(u16 *)payload, dest);
  53                 break;
  54         case 1:
  55                 writeb_relaxed(*(u8 *)payload, dest);
  56                 break;
  57         default:
  58                 break;
  59         }
  60 }
  61
  62 static ssize_t notrace sth_stm_packet(struct stm_data *stm_data,
  63                                       unsigned int master,
  64                                       unsigned int channel,
  65                                       unsigned int packet,
  66                                       unsigned int flags,
  67                                       unsigned int size,
  68                                       const unsigned char *payload)
  69 {
  70         struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
  71         struct intel_th_channel __iomem *out =
  72                 sth_channel(sth, master, channel);
  73         u64 __iomem *outp = &out->Dn;
  74         unsigned long reg = REG_STH_TRIG;
  75
  76 #ifndef CONFIG_64BIT
  77         if (size > 4)
  78                 size = 4;
  79 #endif
  80
  81         size = rounddown_pow_of_two(size);
  82
  83         switch (packet) {
  84         /* Global packets (GERR, XSYNC, TRIG) are sent with register writes */
  85         case STP_PACKET_GERR:
  86                 reg += 4;
  87                 fallthrough;
  88
  89         case STP_PACKET_XSYNC:
  90                 reg += 8;
  91                 fallthrough;
  92
  93         case STP_PACKET_TRIG:
  94                 if (flags & STP_PACKET_TIMESTAMPED)
  95                         reg += 4;
  96                 writeb_relaxed(*payload, sth->base + reg);
  97                 break;
  98
  99         case STP_PACKET_MERR:
 100                 if (size > 4)
 101                         size = 4;
 102
 103                 sth_iowrite(&out->MERR, payload, size);
 104                 break;
 105
 106         case STP_PACKET_FLAG:
 107                 if (flags & STP_PACKET_TIMESTAMPED)
 108                         outp = (u64 __iomem *)&out->FLAG_TS;
 109                 else
 110                         outp = (u64 __iomem *)&out->FLAG;
 111
 112                 size = 0;
 113                 writeb_relaxed(0, outp);
 114                 break;
 115
 116         case STP_PACKET_USER:
 117                 if (flags & STP_PACKET_TIMESTAMPED)
 118                         outp = &out->USER_TS;
 119                 else
 120                         outp = &out->USER;
 121                 sth_iowrite(outp, payload, size);
 122                 break;
 123
 124         case STP_PACKET_DATA:
 125                 outp = &out->Dn;
 126
 127                 if (flags & STP_PACKET_TIMESTAMPED)
 128                         outp += 2;
 129                 if (flags & STP_PACKET_MARKED)
 130                         outp++;
 131
 132                 sth_iowrite(outp, payload, size);
 133                 break;
 134         default:
 135                 return -ENOTSUPP;
 136         }
 137
 138         return size;
 139 }
 140
 141 static phys_addr_t
 142 sth_stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
 143                   unsigned int channel, unsigned int nr_chans)
 144 {
 145         struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
 146         phys_addr_t addr;
 147
 148         master -= sth->stm.sw_start;
 149         addr = sth->channels_phys + (master * sth->stm.sw_nchannels + channel) *
 150                 sizeof(struct intel_th_channel);
 151
 152         if (offset_in_page(addr) ||
 153             offset_in_page(nr_chans * sizeof(struct intel_th_channel)))
 154                 return 0;
 155
 156         return addr;
 157 }
 158
 159 static int sth_stm_link(struct stm_data *stm_data, unsigned int master,
 160                          unsigned int channel)
 161 {
 162         struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
 163
 164         return intel_th_set_output(to_intel_th_device(sth->dev), master);
 165 }
 166
 167 static int intel_th_sw_init(struct sth_device *sth)
 168 {
 169         u32 reg;
 170
 171         reg = ioread32(sth->base + REG_STH_STHCAP1);
 172         sth->stm.sw_nchannels = reg & 0xff;
 173
 174         reg = ioread32(sth->base + REG_STH_STHCAP0);
 175         sth->stm.sw_start = reg & 0xffff;
 176         sth->stm.sw_end = reg >> 16;
 177
 178         sth->sw_nmasters = sth->stm.sw_end - sth->stm.sw_start;
 179         dev_dbg(sth->dev, "sw_start: %x sw_end: %x masters: %x nchannels: %x\n",
 180                 sth->stm.sw_start, sth->stm.sw_end, sth->sw_nmasters,
 181                 sth->stm.sw_nchannels);
 182
 183         return 0;
 184 }
 185
 186 static int intel_th_sth_probe(struct intel_th_device *thdev)
 187 {
 188         struct device *dev = &thdev->dev;
 189         struct sth_device *sth;
 190         struct resource *res;
 191         void __iomem *base, *channels;
 192         int err;
 193
 194         res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
 195         if (!res)
 196                 return -ENODEV;
 197
 198         base = devm_ioremap(dev, res->start, resource_size(res));
 199         if (!base)
 200                 return -ENOMEM;
 201
 202         res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 1);
 203         if (!res)
 204                 return -ENODEV;
 205
 206         channels = devm_ioremap(dev, res->start, resource_size(res));
 207         if (!channels)
 208                 return -ENOMEM;
 209
 210         sth = devm_kzalloc(dev, sizeof(*sth), GFP_KERNEL);
 211         if (!sth)
 212                 return -ENOMEM;
 213
 214         sth->dev = dev;
 215         sth->base = base;
 216         sth->channels = channels;
 217         sth->channels_phys = res->start;
 218         sth->stm.name = dev_name(dev);
 219         sth->stm.packet = sth_stm_packet;
 220         sth->stm.mmio_addr = sth_stm_mmio_addr;
 221         sth->stm.sw_mmiosz = sizeof(struct intel_th_channel);
 222         sth->stm.link = sth_stm_link;
 223
 224         err = intel_th_sw_init(sth);
 225         if (err)
 226                 return err;
 227
 228         err = stm_register_device(dev, &sth->stm, THIS_MODULE);
 229         if (err) {
 230                 dev_err(dev, "stm_register_device failed\n");
 231                 return err;
 232         }
 233
 234         dev_set_drvdata(dev, sth);
 235
 236         return 0;
 237 }
 238
 239 static void intel_th_sth_remove(struct intel_th_device *thdev)
 240 {
 241         struct sth_device *sth = dev_get_drvdata(&thdev->dev);
 242
 243         stm_unregister_device(&sth->stm);
 244 }
 245
 246 static struct intel_th_driver intel_th_sth_driver = {
 247         .probe  = intel_th_sth_probe,
 248         .remove = intel_th_sth_remove,
 249         .driver = {
 250                 .name   = "sth",
 251                 .owner  = THIS_MODULE,
 252         },
 253 };
 254
 255 module_driver(intel_th_sth_driver,
 256               intel_th_driver_register,
 257               intel_th_driver_unregister);
 258
 259 MODULE_LICENSE("GPL v2");
 260 MODULE_DESCRIPTION("Intel(R) Trace Hub Software Trace Hub driver");
 261 MODULE_AUTHOR("Alexander Shishkin <[email protected]>");