Quelle  coresight-funnel.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
 *
 * Description: CoreSight Funnel driver
 */

#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/coresight.h>
#include <linux/amba/bus.h>
#include <linux/clk.h>

#include "coresight-priv.h"

#define FUNNEL_FUNCTL  0x000
#define FUNNEL_PRICTL  0x004

#define FUNNEL_HOLDTIME_MASK 0xf00
#define FUNNEL_HOLDTIME_SHFT 0x8
#define FUNNEL_HOLDTIME  (0x7 << FUNNEL_HOLDTIME_SHFT)
#define FUNNEL_ENSx_MASK 0xff

DEFINE_CORESIGHT_DEVLIST(funnel_devs, "funnel");

/**
 * struct funnel_drvdata - specifics associated to a funnel component
 * @base: memory mapped base address for this component.
 * @atclk: optional clock for the core parts of the funnel.
 * @pclk: APB clock if present, otherwise NULL
 * @csdev: component vitals needed by the framework.
 * @priority: port selection order.
 * @spinlock: serialize enable/disable operations.
 */
struct funnel_drvdata {
 void __iomem  *base;
 struct clk  *atclk;
 struct clk  *pclk;
 struct coresight_device *csdev;
 unsigned long  priority;
 raw_spinlock_t  spinlock;
};

static int dynamic_funnel_enable_hw(struct funnel_drvdata *drvdata, int port)
{
 u32 functl;
 int rc = 0;
 struct coresight_device *csdev = drvdata->csdev;

 CS_UNLOCK(drvdata->base);

 functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
 /* Claim the device only when we enable the first slave */
 if (!(functl & FUNNEL_ENSx_MASK)) {
  rc = coresight_claim_device_unlocked(csdev);
  if (rc)
   goto done;
 }

 functl &= ~FUNNEL_HOLDTIME_MASK;
 functl |= FUNNEL_HOLDTIME;
 functl |= (1 << port);
 writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);
 writel_relaxed(drvdata->priority, drvdata->base + FUNNEL_PRICTL);
done:
 CS_LOCK(drvdata->base);
 return rc;
}

static int funnel_enable(struct coresight_device *csdev,
    struct coresight_connection *in,
    struct coresight_connection *out)
{
 int rc = 0;
 struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 unsigned long flags;
 bool first_enable = false;

 raw_spin_lock_irqsave(&drvdata->spinlock, flags);
 if (in->dest_refcnt == 0) {
  if (drvdata->base)
   rc = dynamic_funnel_enable_hw(drvdata, in->dest_port);
  if (!rc)
   first_enable = true;
 }
 if (!rc)
  in->dest_refcnt++;
 raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);

 if (first_enable)
  dev_dbg(&csdev->dev, "FUNNEL inport %d enabled\n",
   in->dest_port);
 return rc;
}

static void dynamic_funnel_disable_hw(struct funnel_drvdata *drvdata,
          int inport)
{
 u32 functl;
 struct coresight_device *csdev = drvdata->csdev;

 CS_UNLOCK(drvdata->base);

 functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
 functl &= ~(1 << inport);
 writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);

 /* Disclaim the device if none of the slaves are now active */
 if (!(functl & FUNNEL_ENSx_MASK))
  coresight_disclaim_device_unlocked(csdev);

 CS_LOCK(drvdata->base);
}

static void funnel_disable(struct coresight_device *csdev,
      struct coresight_connection *in,
      struct coresight_connection *out)
{
 struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 unsigned long flags;
 bool last_disable = false;

 raw_spin_lock_irqsave(&drvdata->spinlock, flags);
 if (--in->dest_refcnt == 0) {
  if (drvdata->base)
   dynamic_funnel_disable_hw(drvdata, in->dest_port);
  last_disable = true;
 }
 raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);

 if (last_disable)
  dev_dbg(&csdev->dev, "FUNNEL inport %d disabled\n",
   in->dest_port);
}

static const struct coresight_ops_link funnel_link_ops = {
 .enable  = funnel_enable,
 .disable = funnel_disable,
};

static const struct coresight_ops funnel_cs_ops = {
 .link_ops = &funnel_link_ops,
};

static ssize_t priority_show(struct device *dev,
        struct device_attribute *attr, char *buf)
{
 struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);
 unsigned long val = drvdata->priority;

 return sprintf(buf, "%#lx\n", val);
}

static ssize_t priority_store(struct device *dev,
         struct device_attribute *attr,
         const char *buf, size_t size)
{
 int ret;
 unsigned long val;
 struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);

 ret = kstrtoul(buf, 16, &val);
 if (ret)
  return ret;

 drvdata->priority = val;
 return size;
}
static DEVICE_ATTR_RW(priority);

static u32 get_funnel_ctrl_hw(struct funnel_drvdata *drvdata)
{
 u32 functl;

 CS_UNLOCK(drvdata->base);
 functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
 CS_LOCK(drvdata->base);

 return functl;
}

static ssize_t funnel_ctrl_show(struct device *dev,
        struct device_attribute *attr, char *buf)
{
 u32 val;
 struct funnel_drvdata *drvdata = dev_get_drvdata(dev->parent);

 pm_runtime_get_sync(dev->parent);

 val = get_funnel_ctrl_hw(drvdata);

 pm_runtime_put(dev->parent);

 return sprintf(buf, "%#x\n", val);
}
static DEVICE_ATTR_RO(funnel_ctrl);

static struct attribute *coresight_funnel_attrs[] = {
 &dev_attr_funnel_ctrl.attr,
 &dev_attr_priority.attr,
 NULL,
};
ATTRIBUTE_GROUPS(coresight_funnel);

static int funnel_probe(struct device *dev, struct resource *res)
{
 void __iomem *base;
 struct coresight_platform_data *pdata = NULL;
 struct funnel_drvdata *drvdata;
 struct coresight_desc desc = { 0 };

 if (is_of_node(dev_fwnode(dev)) &&
     of_device_is_compatible(dev->of_node, "arm,coresight-funnel"))
  dev_warn_once(dev, "Uses OBSOLETE CoreSight funnel binding\n");

 desc.name = coresight_alloc_device_name(&funnel_devs, dev);
 if (!desc.name)
  return -ENOMEM;

 drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
 if (!drvdata)
  return -ENOMEM;

 drvdata->atclk = devm_clk_get_optional_enabled(dev, "atclk");
 if (IS_ERR(drvdata->atclk))
  return PTR_ERR(drvdata->atclk);

 drvdata->pclk = coresight_get_enable_apb_pclk(dev);
 if (IS_ERR(drvdata->pclk))
  return PTR_ERR(drvdata->pclk);

 /*
 * Map the device base for dynamic-funnel, which has been
 * validated by AMBA core.
 */
 if (res) {
  base = devm_ioremap_resource(dev, res);
  if (IS_ERR(base))
   return PTR_ERR(base);
  drvdata->base = base;
  desc.groups = coresight_funnel_groups;
  desc.access = CSDEV_ACCESS_IOMEM(base);
  coresight_clear_self_claim_tag(&desc.access);
 }

 dev_set_drvdata(dev, drvdata);

 pdata = coresight_get_platform_data(dev);
 if (IS_ERR(pdata))
  return PTR_ERR(pdata);

 dev->platform_data = pdata;

 raw_spin_lock_init(&drvdata->spinlock);
 desc.type = CORESIGHT_DEV_TYPE_LINK;
 desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG;
 desc.ops = &funnel_cs_ops;
 desc.pdata = pdata;
 desc.dev = dev;
 drvdata->csdev = coresight_register(&desc);
 if (IS_ERR(drvdata->csdev))
  return PTR_ERR(drvdata->csdev);

 return 0;
}

static int funnel_remove(struct device *dev)
{
 struct funnel_drvdata *drvdata = dev_get_drvdata(dev);

 coresight_unregister(drvdata->csdev);

 return 0;
}

#ifdef CONFIG_PM
static int funnel_runtime_suspend(struct device *dev)
{
 struct funnel_drvdata *drvdata = dev_get_drvdata(dev);

 if (drvdata && !IS_ERR(drvdata->atclk))
  clk_disable_unprepare(drvdata->atclk);

 if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
  clk_disable_unprepare(drvdata->pclk);

 return 0;
}

static int funnel_runtime_resume(struct device *dev)
{
 struct funnel_drvdata *drvdata = dev_get_drvdata(dev);

 if (drvdata && !IS_ERR(drvdata->atclk))
  clk_prepare_enable(drvdata->atclk);

 if (drvdata && !IS_ERR_OR_NULL(drvdata->pclk))
  clk_prepare_enable(drvdata->pclk);
 return 0;
}
#endif

static const struct dev_pm_ops funnel_dev_pm_ops = {
 SET_RUNTIME_PM_OPS(funnel_runtime_suspend, funnel_runtime_resume, NULL)
};

static int funnel_platform_probe(struct platform_device *pdev)
{
 struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 int ret;

 pm_runtime_get_noresume(&pdev->dev);
 pm_runtime_set_active(&pdev->dev);
 pm_runtime_enable(&pdev->dev);

 ret = funnel_probe(&pdev->dev, res);
 pm_runtime_put(&pdev->dev);
 if (ret)
  pm_runtime_disable(&pdev->dev);

 return ret;
}

static void funnel_platform_remove(struct platform_device *pdev)
{
 struct funnel_drvdata *drvdata = dev_get_drvdata(&pdev->dev);

 if (WARN_ON(!drvdata))
  return;

 funnel_remove(&pdev->dev);
 pm_runtime_disable(&pdev->dev);
}

static const struct of_device_id funnel_match[] = {
 {.compatible = "arm,coresight-static-funnel"},
 {}
};

MODULE_DEVICE_TABLE(of, funnel_match);

#ifdef CONFIG_ACPI
static const struct acpi_device_id funnel_acpi_ids[] = {
 {"ARMHC9FE", 0, 0, 0}, /* ARM Coresight Static Funnel */
 {"ARMHC9FF", 0, 0, 0}, /* ARM CoreSight Dynamic Funnel */
 {},
};

MODULE_DEVICE_TABLE(acpi, funnel_acpi_ids);
#endif

static struct platform_driver funnel_driver = {
 .probe  = funnel_platform_probe,
 .remove  = funnel_platform_remove,
 .driver  = {
  .name   = "coresight-funnel",
  /* THIS_MODULE is taken care of by platform_driver_register() */
  .of_match_table = funnel_match,
  .acpi_match_table = ACPI_PTR(funnel_acpi_ids),
  .pm = &funnel_dev_pm_ops,
  .suppress_bind_attrs = true,
 },
};

static int dynamic_funnel_probe(struct amba_device *adev,
    const struct amba_id *id)
{
 int ret;

 ret = funnel_probe(&adev->dev, &adev->res);
 if (!ret)
  pm_runtime_put(&adev->dev);

 return ret;
}

static void dynamic_funnel_remove(struct amba_device *adev)
{
 funnel_remove(&adev->dev);
}

static const struct amba_id dynamic_funnel_ids[] = {
 {
  .id     = 0x000bb908,
  .mask   = 0x000fffff,
 },
 {
  /* Coresight SoC-600 */
  .id     = 0x000bb9eb,
  .mask   = 0x000fffff,
 },
 { 0, 0, NULL },
};

MODULE_DEVICE_TABLE(amba, dynamic_funnel_ids);

static struct amba_driver dynamic_funnel_driver = {
 .drv = {
  .name = "coresight-dynamic-funnel",
  .pm = &funnel_dev_pm_ops,
  .suppress_bind_attrs = true,
 },
 .probe  = dynamic_funnel_probe,
 .remove  = dynamic_funnel_remove,
 .id_table = dynamic_funnel_ids,
};

static int __init funnel_init(void)
{
 return coresight_init_driver("funnel", &dynamic_funnel_driver, &funnel_driver,
         THIS_MODULE);
}

static void __exit funnel_exit(void)
{
 coresight_remove_driver(&dynamic_funnel_driver, &funnel_driver);
}

module_init(funnel_init);
module_exit(funnel_exit);

MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");
MODULE_DESCRIPTION("Arm CoreSight Funnel Driver");
MODULE_LICENSE("GPL v2");