linux/drivers/hwtracing/coresight/coresight-funnel.c
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   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 */
  44struct 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
  52static 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
  68static 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
  79static 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
  92static 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
 102static const struct coresight_ops_link funnel_link_ops = {
 103        .enable         = funnel_enable,
 104        .disable        = funnel_disable,
 105};
 106
 107static const struct coresight_ops funnel_cs_ops = {
 108        .link_ops       = &funnel_link_ops,
 109};
 110
 111static 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
 120static 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}
 135static DEVICE_ATTR_RW(priority);
 136
 137static 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
 148static 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}
 162static DEVICE_ATTR_RO(funnel_ctrl);
 163
 164static struct attribute *coresight_funnel_attrs[] = {
 165        &dev_attr_funnel_ctrl.attr,
 166        &dev_attr_priority.attr,
 167        NULL,
 168};
 169ATTRIBUTE_GROUPS(coresight_funnel);
 170
 171static 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
 224static 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
 234static 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
 245static const struct dev_pm_ops funnel_dev_pm_ops = {
 246        SET_RUNTIME_PM_OPS(funnel_runtime_suspend, funnel_runtime_resume, NULL)
 247};
 248
 249static struct amba_id funnel_ids[] = {
 250        {
 251                .id     = 0x0003b908,
 252                .mask   = 0x0003ffff,
 253        },
 254        { 0, 0},
 255};
 256
 257static 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};
 267builtin_amba_driver(funnel_driver);
 268