drivers/coresight/coresight-funnel.c

   1 /* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License version 2 and
   5  * only version 2 as published by the Free Software Foundation.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/types.h>
  17 #include <linux/device.h>
  18 #include <linux/err.h>
  19 #include <linux/fs.h>
  20 #include <linux/slab.h>
  21 #include <linux/clk.h>
  22 #include <linux/coresight.h>
  23 #include <linux/amba/bus.h>
  24
  25 #include "coresight-priv.h"
  26
  27 #define FUNNEL_FUNCTL           0x000
  28 #define FUNNEL_PRICTL           0x004
  29
  30 #define FUNNEL_HOLDTIME_MASK    0xf00
  31 #define FUNNEL_HOLDTIME_SHFT    0x8
  32 #define FUNNEL_HOLDTIME         (0x7 << FUNNEL_HOLDTIME_SHFT)
  33
  34 /**
  35  * struct funnel_drvdata - specifics associated to a funnel component
  36  * @base:       memory mapped base address for this component.
  37  * @dev:        the device entity associated to this component.
  38  * @csdev:      component vitals needed by the framework.
  39  * @clk:        the clock this component is associated to.
  40  * @priority:   port selection order.
  41  */
  42 struct funnel_drvdata {
  43         void __iomem            *base;
  44         struct device           *dev;
  45         struct coresight_device *csdev;
  46         struct clk              *clk;
  47         unsigned long           priority;
  48 };
  49
  50 static void funnel_enable_hw(struct funnel_drvdata *drvdata, int port)
  51 {
  52         u32 functl;
  53
  54         CS_UNLOCK(drvdata->base);
  55
  56         functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
  57         functl &= ~FUNNEL_HOLDTIME_MASK;
  58         functl |= FUNNEL_HOLDTIME;
  59         functl |= (1 << port);
  60         writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);
  61         writel_relaxed(drvdata->priority, drvdata->base + FUNNEL_PRICTL);
  62
  63         CS_LOCK(drvdata->base);
  64 }
  65
  66 static int funnel_enable(struct coresight_device *csdev, int inport,
  67                          int outport)
  68 {
  69         struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  70         int ret;
  71
  72         ret = clk_prepare_enable(drvdata->clk);
  73         if (ret)
  74                 return ret;
  75
  76         funnel_enable_hw(drvdata, inport);
  77
  78         dev_info(drvdata->dev, "FUNNEL inport %d enabled\n", inport);
  79         return 0;
  80 }
  81
  82 static void funnel_disable_hw(struct funnel_drvdata *drvdata, int inport)
  83 {
  84         u32 functl;
  85
  86         CS_UNLOCK(drvdata->base);
  87
  88         functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
  89         functl &= ~(1 << inport);
  90         writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);
  91
  92         CS_LOCK(drvdata->base);
  93 }
  94
  95 static void funnel_disable(struct coresight_device *csdev, int inport,
  96                            int outport)
  97 {
  98         struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  99
 100         funnel_disable_hw(drvdata, inport);
 101
 102         clk_disable_unprepare(drvdata->clk);
 103
 104         dev_info(drvdata->dev, "FUNNEL inport %d disabled\n", inport);
 105 }
 106
 107 static const struct coresight_ops_link funnel_link_ops = {
 108         .enable         = funnel_enable,
 109         .disable        = funnel_disable,
 110 };
 111
 112 static const struct coresight_ops funnel_cs_ops = {
 113         .link_ops       = &funnel_link_ops,
 114 };
 115
 116 static ssize_t priority_show(struct device *dev,
 117                              struct device_attribute *attr, char *buf)
 118 {
 119         struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
 120         unsigned long val = drvdata->priority;
 121
 122         return sprintf(buf, "%#lx\n", val);
 123 }
 124
 125 static ssize_t priority_store(struct device *dev,
 126                               struct device_attribute *attr,
 127                               const char *buf, size_t size)
 128 {
 129         int ret;
 130         unsigned long val;
 131         struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
 132
 133         ret = kstrtoul(buf, 16, &val);
 134         if (ret)
 135                 return ret;
 136
 137         drvdata->priority = val;
 138         return size;
 139 }
 140 static DEVICE_ATTR_RW(priority);
 141
 142 static u32 get_funnel_ctrl_hw(struct funnel_drvdata *drvdata)
 143 {
 144         u32 functl;
 145
 146         CS_UNLOCK(drvdata->base);
 147         functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
 148         CS_LOCK(drvdata->base);
 149
 150         return functl;
 151 }
 152
 153 static ssize_t funnel_ctrl_show(struct device *dev,
 154                              struct device_attribute *attr, char *buf)
 155 {
 156         int ret;
 157         u32 val;
 158         struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
 159
 160         ret = clk_prepare_enable(drvdata->clk);
 161         if (ret)
 162                 return ret;
 163
 164         val = get_funnel_ctrl_hw(drvdata);
 165         clk_disable_unprepare(drvdata->clk);
 166
 167         return sprintf(buf, "%#x\n", val);
 168 }
 169 static DEVICE_ATTR_RO(funnel_ctrl);
 170
 171 static struct attribute *coresight_funnel_attrs[] = {
 172         &dev_attr_funnel_ctrl.attr,
 173         &dev_attr_priority.attr,
 174         NULL,
 175 };
 176 ATTRIBUTE_GROUPS(coresight_funnel);
 177
 178 static int funnel_probe(struct amba_device *adev, const struct amba_id *id)
 179 {
 180         void __iomem *base;
 181         struct device *dev = &adev->dev;
 182         struct coresight_platform_data *pdata = NULL;
 183         struct funnel_drvdata *drvdata;
 184         struct resource *res = &adev->res;
 185         struct coresight_desc *desc;
 186         struct device_node *np = adev->dev.of_node;
 187
 188         if (np) {
 189                 pdata = of_get_coresight_platform_data(dev, np);
 190                 if (IS_ERR(pdata))
 191                         return PTR_ERR(pdata);
 192                 adev->dev.platform_data = pdata;
 193         }
 194
 195         drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
 196         if (!drvdata)
 197                 return -ENOMEM;
 198
 199         drvdata->dev = &adev->dev;
 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
 209         drvdata->clk = adev->pclk;
 210
 211         desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
 212         if (!desc)
 213                 return -ENOMEM;
 214
 215         desc->type = CORESIGHT_DEV_TYPE_LINK;
 216         desc->subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG;
 217         desc->ops = &funnel_cs_ops;
 218         desc->pdata = pdata;
 219         desc->dev = dev;
 220         desc->groups = coresight_funnel_groups;
 221         drvdata->csdev = coresight_register(desc);
 222         if (IS_ERR(drvdata->csdev))
 223                 return PTR_ERR(drvdata->csdev);
 224
 225         dev_info(dev, "FUNNEL initialized\n");
 226         return 0;
 227 }
 228
 229 static int funnel_remove(struct amba_device *adev)
 230 {
 231         struct funnel_drvdata *drvdata = amba_get_drvdata(adev);
 232
 233         coresight_unregister(drvdata->csdev);
 234         return 0;
 235 }
 236
 237 static struct amba_id funnel_ids[] = {
 238         {
 239                 .id     = 0x0003b908,
 240                 .mask   = 0x0003ffff,
 241         },
 242         { 0, 0},
 243 };
 244
 245 static struct amba_driver funnel_driver = {
 246         .drv = {
 247                 .name   = "coresight-funnel",
 248                 .owner  = THIS_MODULE,
 249         },
 250         .probe          = funnel_probe,
 251         .remove         = funnel_remove,
 252         .id_table       = funnel_ids,
 253 };
 254
 255 module_amba_driver(funnel_driver);
 256
 257 MODULE_LICENSE("GPL v2");
 258 MODULE_DESCRIPTION("CoreSight Funnel driver");