drivers/hwtracing/coresight/coresight-tpda.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
   4  */
   5
   6 #include <linux/amba/bus.h>
   7 #include <linux/bitfield.h>
   8 #include <linux/coresight.h>
   9 #include <linux/device.h>
  10 #include <linux/err.h>
  11 #include <linux/fs.h>
  12 #include <linux/io.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/of.h>
  16 #include <linux/platform_device.h>
  17
  18 #include "coresight-priv.h"
  19 #include "coresight-tpda.h"
  20 #include "coresight-trace-id.h"
  21
  22 DEFINE_CORESIGHT_DEVLIST(tpda_devs, "tpda");
  23
  24 /* Settings pre enabling port control register */
  25 static void tpda_enable_pre_port(struct tpda_drvdata *drvdata)
  26 {
  27         u32 val;
  28
  29         val = readl_relaxed(drvdata->base + TPDA_CR);
  30         val &= ~TPDA_CR_ATID;
  31         val |= FIELD_PREP(TPDA_CR_ATID, drvdata->atid);
  32         writel_relaxed(val, drvdata->base + TPDA_CR);
  33 }
  34
  35 static void tpda_enable_port(struct tpda_drvdata *drvdata, int port)
  36 {
  37         u32 val;
  38
  39         val = readl_relaxed(drvdata->base + TPDA_Pn_CR(port));
  40         /* Enable the port */
  41         val |= TPDA_Pn_CR_ENA;
  42         writel_relaxed(val, drvdata->base + TPDA_Pn_CR(port));
  43 }
  44
  45 static void __tpda_enable(struct tpda_drvdata *drvdata, int port)
  46 {
  47         CS_UNLOCK(drvdata->base);
  48
  49         if (!drvdata->csdev->enable)
  50                 tpda_enable_pre_port(drvdata);
  51
  52         tpda_enable_port(drvdata, port);
  53
  54         CS_LOCK(drvdata->base);
  55 }
  56
  57 static int tpda_enable(struct coresight_device *csdev, int inport, int outport)
  58 {
  59         struct tpda_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  60
  61         spin_lock(&drvdata->spinlock);
  62         if (atomic_read(&csdev->refcnt[inport]) == 0)
  63                 __tpda_enable(drvdata, inport);
  64
  65         atomic_inc(&csdev->refcnt[inport]);
  66         spin_unlock(&drvdata->spinlock);
  67
  68         dev_dbg(drvdata->dev, "TPDA inport %d enabled.\n", inport);
  69         return 0;
  70 }
  71
  72 static void __tpda_disable(struct tpda_drvdata *drvdata, int port)
  73 {
  74         u32 val;
  75
  76         CS_UNLOCK(drvdata->base);
  77
  78         val = readl_relaxed(drvdata->base + TPDA_Pn_CR(port));
  79         val &= ~TPDA_Pn_CR_ENA;
  80         writel_relaxed(val, drvdata->base + TPDA_Pn_CR(port));
  81
  82         CS_LOCK(drvdata->base);
  83 }
  84
  85 static void tpda_disable(struct coresight_device *csdev, int inport,
  86                            int outport)
  87 {
  88         struct tpda_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  89
  90         spin_lock(&drvdata->spinlock);
  91         if (atomic_dec_return(&csdev->refcnt[inport]) == 0)
  92                 __tpda_disable(drvdata, inport);
  93
  94         spin_unlock(&drvdata->spinlock);
  95
  96         dev_dbg(drvdata->dev, "TPDA inport %d disabled\n", inport);
  97 }
  98
  99 static const struct coresight_ops_link tpda_link_ops = {
 100         .enable         = tpda_enable,
 101         .disable        = tpda_disable,
 102 };
 103
 104 static const struct coresight_ops tpda_cs_ops = {
 105         .link_ops       = &tpda_link_ops,
 106 };
 107
 108 static int tpda_init_default_data(struct tpda_drvdata *drvdata)
 109 {
 110         int atid;
 111         /*
 112          * TPDA must has a unique atid. This atid can uniquely
 113          * identify the TPDM trace source connected to the TPDA.
 114          * The TPDMs which are connected to same TPDA share the
 115          * same trace-id. When TPDA does packetization, different
 116          * port will have unique channel number for decoding.
 117          */
 118         atid = coresight_trace_id_get_system_id();
 119         if (atid < 0)
 120                 return atid;
 121
 122         drvdata->atid = atid;
 123         return 0;
 124 }
 125
 126 static int tpda_probe(struct amba_device *adev, const struct amba_id *id)
 127 {
 128         int ret;
 129         struct device *dev = &adev->dev;
 130         struct coresight_platform_data *pdata;
 131         struct tpda_drvdata *drvdata;
 132         struct coresight_desc desc = { 0 };
 133         void __iomem *base;
 134
 135         pdata = coresight_get_platform_data(dev);
 136         if (IS_ERR(pdata))
 137                 return PTR_ERR(pdata);
 138         adev->dev.platform_data = pdata;
 139
 140         drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
 141         if (!drvdata)
 142                 return -ENOMEM;
 143
 144         drvdata->dev = &adev->dev;
 145         dev_set_drvdata(dev, drvdata);
 146
 147         base = devm_ioremap_resource(dev, &adev->res);
 148         if (IS_ERR(base))
 149                 return PTR_ERR(base);
 150         drvdata->base = base;
 151
 152         spin_lock_init(&drvdata->spinlock);
 153
 154         ret = tpda_init_default_data(drvdata);
 155         if (ret)
 156                 return ret;
 157
 158         desc.name = coresight_alloc_device_name(&tpda_devs, dev);
 159         if (!desc.name)
 160                 return -ENOMEM;
 161         desc.type = CORESIGHT_DEV_TYPE_LINK;
 162         desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG;
 163         desc.ops = &tpda_cs_ops;
 164         desc.pdata = adev->dev.platform_data;
 165         desc.dev = &adev->dev;
 166         desc.access = CSDEV_ACCESS_IOMEM(base);
 167         drvdata->csdev = coresight_register(&desc);
 168         if (IS_ERR(drvdata->csdev))
 169                 return PTR_ERR(drvdata->csdev);
 170
 171         pm_runtime_put(&adev->dev);
 172
 173         dev_dbg(drvdata->dev, "TPDA initialized\n");
 174         return 0;
 175 }
 176
 177 static void tpda_remove(struct amba_device *adev)
 178 {
 179         struct tpda_drvdata *drvdata = dev_get_drvdata(&adev->dev);
 180
 181         coresight_trace_id_put_system_id(drvdata->atid);
 182         coresight_unregister(drvdata->csdev);
 183 }
 184
 185 /*
 186  * Different TPDA has different periph id.
 187  * The difference is 0-7 bits' value. So ignore 0-7 bits.
 188  */
 189 static struct amba_id tpda_ids[] = {
 190         {
 191                 .id     = 0x000f0f00,
 192                 .mask   = 0x000fff00,
 193         },
 194         { 0, 0},
 195 };
 196
 197 static struct amba_driver tpda_driver = {
 198         .drv = {
 199                 .name   = "coresight-tpda",
 200                 .owner  = THIS_MODULE,
 201                 .suppress_bind_attrs = true,
 202         },
 203         .probe          = tpda_probe,
 204         .remove         = tpda_remove,
 205         .id_table       = tpda_ids,
 206 };
 207
 208 module_amba_driver(tpda_driver);
 209
 210 MODULE_LICENSE("GPL");
 211 MODULE_DESCRIPTION("Trace, Profiling & Diagnostic Aggregator driver");