drivers/hwtracing/coresight/coresight-funnel.c

   1 /* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
   2  *
   3  * Description: CoreSight Funnel driver
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 and
   7  * only version 2 as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/init.h>
  17 #include <linux/types.h>
  18 #include <linux/device.h>
  19 #include <linux/err.h>
  20 #include <linux/fs.h>
  21 #include <linux/slab.h>
  22 #include <linux/pm_runtime.h>
  23 #include <linux/coresight.h>
  24 #include <linux/amba/bus.h>
  25 #include <linux/clk.h>
  26
  27 #include "coresight-priv.h"
  28
  29 #define FUNNEL_FUNCTL           0x000
  30 #define FUNNEL_PRICTL           0x004
  31
  32 #define FUNNEL_HOLDTIME_MASK    0xf00
  33 #define FUNNEL_HOLDTIME_SHFT    0x8
  34 #define FUNNEL_HOLDTIME         (0x7 << FUNNEL_HOLDTIME_SHFT)
  35
  36 /**
  37  * struct funnel_drvdata - specifics associated to a funnel component
  38  * @base:       memory mapped base address for this component.
  39  * @dev:        the device entity associated to this component.
  40  * @atclk:      optional clock for the core parts of the funnel.
  41  * @csdev:      component vitals needed by the framework.
  42  * @priority:   port selection order.
  43  */
  44 struct funnel_drvdata {
  45         void __iomem            *base;
  46         struct device           *dev;
  47         struct clk              *atclk;
  48         struct coresight_device *csdev;
  49         unsigned long           priority;
  50 };
  51
  52 static void funnel_enable_hw(struct funnel_drvdata *drvdata, int port)
  53 {
  54         u32 functl;
  55
  56         CS_UNLOCK(drvdata->base);
  57
  58         functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
  59         functl &= ~FUNNEL_HOLDTIME_MASK;
  60         functl |= FUNNEL_HOLDTIME;
  61         functl |= (1 << port);
  62         writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);
  63         writel_relaxed(drvdata->priority, drvdata->base + FUNNEL_PRICTL);
  64
  65         CS_LOCK(drvdata->base);
  66 }
  67
  68 static int funnel_enable(struct coresight_device *csdev, int inport,
  69                          int outport)
  70 {
  71         struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  72
  73         funnel_enable_hw(drvdata, inport);
  74
  75         dev_info(drvdata->dev, "FUNNEL inport %d enabled\n", inport);
  76         return 0;
  77 }
  78
  79 static void funnel_disable_hw(struct funnel_drvdata *drvdata, int inport)
  80 {
  81         u32 functl;
  82
  83         CS_UNLOCK(drvdata->base);
  84
  85         functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
  86         functl &= ~(1 << inport);
  87         writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);
  88
  89         CS_LOCK(drvdata->base);
  90 }
  91
  92 static void funnel_disable(struct coresight_device *csdev, int inport,
  93                            int outport)
  94 {
  95         struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  96
  97         funnel_disable_hw(drvdata, inport);
  98
  99         dev_info(drvdata->dev, "FUNNEL inport %d disabled\n", inport);
 100 }
 101
 102 static const struct coresight_ops_link funnel_link_ops = {
 103         .enable         = funnel_enable,
 104         .disable        = funnel_disable,
 105 };
 106
 107 static const struct coresight_ops funnel_cs_ops = {
 108         .link_ops       = &funnel_link_ops,
 109 };
 110
 111 static ssize_t priority_show(struct device *dev,
 112                              struct device_attribute *attr, char *buf)
 113 {
 114         struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
 115         unsigned long val = drvdata->priority;
 116
 117         return sprintf(buf, "%#lx\n", val);
 118 }
 119
 120 static ssize_t priority_store(struct device *dev,
 121                               struct device_attribute *attr,
 122                               const char *buf, size_t size)
 123 {
 124         int ret;
 125         unsigned long val;
 126         struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
 127
 128         ret = kstrtoul(buf, 16, &val);
 129         if (ret)
 130                 return ret;
 131
 132         drvdata->priority = val;
 133         return size;
 134 }
 135 static DEVICE_ATTR_RW(priority);
 136
 137 static u32 get_funnel_ctrl_hw(struct funnel_drvdata *drvdata)
 138 {
 139         u32 functl;
 140
 141         CS_UNLOCK(drvdata->base);
 142         functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
 143         CS_LOCK(drvdata->base);
 144
 145         return functl;
 146 }
 147
 148 static ssize_t funnel_ctrl_show(struct device *dev,
 149                              struct device_attribute *attr, char *buf)
 150 {
 151         u32 val;
 152         struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
 153
 154         pm_runtime_get_sync(drvdata->dev);
 155
 156         val = get_funnel_ctrl_hw(drvdata);
 157
 158         pm_runtime_put(drvdata->dev);
 159
 160         return sprintf(buf, "%#x\n", val);
 161 }
 162 static DEVICE_ATTR_RO(funnel_ctrl);
 163
 164 static struct attribute *coresight_funnel_attrs[] = {
 165         &dev_attr_funnel_ctrl.attr,
 166         &dev_attr_priority.attr,
 167         NULL,
 168 };
 169 ATTRIBUTE_GROUPS(coresight_funnel);
 170
 171 static int funnel_probe(struct amba_device *adev, const struct amba_id *id)
 172 {
 173         int ret;
 174         void __iomem *base;
 175         struct device *dev = &adev->dev;
 176         struct coresight_platform_data *pdata = NULL;
 177         struct funnel_drvdata *drvdata;
 178         struct resource *res = &adev->res;
 179         struct coresight_desc desc = { 0 };
 180         struct device_node *np = adev->dev.of_node;
 181
 182         if (np) {
 183                 pdata = of_get_coresight_platform_data(dev, np);
 184                 if (IS_ERR(pdata))
 185                         return PTR_ERR(pdata);
 186                 adev->dev.platform_data = pdata;
 187         }
 188
 189         drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
 190         if (!drvdata)
 191                 return -ENOMEM;
 192
 193         drvdata->dev = &adev->dev;
 194         drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
 195         if (!IS_ERR(drvdata->atclk)) {
 196                 ret = clk_prepare_enable(drvdata->atclk);
 197                 if (ret)
 198                         return ret;
 199         }
 200         dev_set_drvdata(dev, drvdata);
 201
 202         /* Validity for the resource is already checked by the AMBA core */
 203         base = devm_ioremap_resource(dev, res);
 204         if (IS_ERR(base))
 205                 return PTR_ERR(base);
 206
 207         drvdata->base = base;
 208         pm_runtime_put(&adev->dev);
 209
 210         desc.type = CORESIGHT_DEV_TYPE_LINK;
 211         desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG;
 212         desc.ops = &funnel_cs_ops;
 213         desc.pdata = pdata;
 214         desc.dev = dev;
 215         desc.groups = coresight_funnel_groups;
 216         drvdata->csdev = coresight_register(&desc);
 217         if (IS_ERR(drvdata->csdev))
 218                 return PTR_ERR(drvdata->csdev);
 219
 220         return 0;
 221 }
 222
 223 #ifdef CONFIG_PM
 224 static int funnel_runtime_suspend(struct device *dev)
 225 {
 226         struct funnel_drvdata *drvdata = dev_get_drvdata(dev);
 227
 228         if (drvdata && !IS_ERR(drvdata->atclk))
 229                 clk_disable_unprepare(drvdata->atclk);
 230
 231         return 0;
 232 }
 233
 234 static int funnel_runtime_resume(struct device *dev)
 235 {
 236         struct funnel_drvdata *drvdata = dev_get_drvdata(dev);
 237
 238         if (drvdata && !IS_ERR(drvdata->atclk))
 239                 clk_prepare_enable(drvdata->atclk);
 240
 241         return 0;
 242 }
 243 #endif
 244
 245 static const struct dev_pm_ops funnel_dev_pm_ops = {
 246         SET_RUNTIME_PM_OPS(funnel_runtime_suspend, funnel_runtime_resume, NULL)
 247 };
 248
 249 static struct amba_id funnel_ids[] = {
 250         {
 251                 .id     = 0x0003b908,
 252                 .mask   = 0x0003ffff,
 253         },
 254         { 0, 0},
 255 };
 256
 257 static struct amba_driver funnel_driver = {
 258         .drv = {
 259                 .name   = "coresight-funnel",
 260                 .owner  = THIS_MODULE,
 261                 .pm     = &funnel_dev_pm_ops,
 262                 .suppress_bind_attrs = true,
 263         },
 264         .probe          = funnel_probe,
 265         .id_table       = funnel_ids,
 266 };
 267 builtin_amba_driver(funnel_driver);