Quelle  coresight-replicator.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
 *
 * Description: CoreSight Replicator driver
 */

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

#include "coresight-priv.h"

#define REPLICATOR_IDFILTER0  0x000
#define REPLICATOR_IDFILTER1  0x004

DEFINE_CORESIGHT_DEVLIST(replicator_devs, "replicator");

/**
 * struct replicator_drvdata - specifics associated to a replicator component
 * @base: memory mapped base address for this component. Also indicates
 * whether this one is programmable or not.
 * @atclk: optional clock for the core parts of the replicator.
 * @pclk: APB clock if present, otherwise NULL
 * @csdev: component vitals needed by the framework
 * @spinlock: serialize enable/disable operations.
 * @check_idfilter_val: check if the context is lost upon clock removal.
 */
struct replicator_drvdata {
 void __iomem  *base;
 struct clk  *atclk;
 struct clk  *pclk;
 struct coresight_device *csdev;
 raw_spinlock_t  spinlock;
 bool   check_idfilter_val;
};

static void dynamic_replicator_reset(struct replicator_drvdata *drvdata)
{
 struct coresight_device *csdev = drvdata->csdev;

 CS_UNLOCK(drvdata->base);

 if (!coresight_claim_device_unlocked(csdev)) {
  writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
  writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
  coresight_disclaim_device_unlocked(csdev);
 }

 CS_LOCK(drvdata->base);
}

/*
 * replicator_reset : Reset the replicator configuration to sane values.
 */
static void replicator_reset(struct replicator_drvdata *drvdata)
{
 if (drvdata->base)
  dynamic_replicator_reset(drvdata);
}

static int dynamic_replicator_enable(struct replicator_drvdata *drvdata,
         int inport, int outport)
{
 int rc = 0;
 u32 id0val, id1val;
 struct coresight_device *csdev = drvdata->csdev;

 CS_UNLOCK(drvdata->base);

 id0val = readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0);
 id1val = readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1);

 /*
 * Some replicator designs lose context when AMBA clocks are removed,
 * so have a check for this.
 */
 if (drvdata->check_idfilter_val && id0val == 0x0 && id1val == 0x0)
  id0val = id1val = 0xff;

 if (id0val == 0xff && id1val == 0xff)
  rc = coresight_claim_device_unlocked(csdev);

 if (!rc) {
  switch (outport) {
  case 0:
   id0val = 0x0;
   break;
  case 1:
   id1val = 0x0;
   break;
  default:
   WARN_ON(1);
   rc = -EINVAL;
  }
 }

 /* Ensure that the outport is enabled. */
 if (!rc) {
  writel_relaxed(id0val, drvdata->base + REPLICATOR_IDFILTER0);
  writel_relaxed(id1val, drvdata->base + REPLICATOR_IDFILTER1);
 }

 CS_LOCK(drvdata->base);

 return rc;
}

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

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

 if (first_enable)
  dev_dbg(&csdev->dev, "REPLICATOR enabled\n");
 return rc;
}

static void dynamic_replicator_disable(struct replicator_drvdata *drvdata,
           int inport, int outport)
{
 u32 reg;
 struct coresight_device *csdev = drvdata->csdev;

 switch (outport) {
 case 0:
  reg = REPLICATOR_IDFILTER0;
  break;
 case 1:
  reg = REPLICATOR_IDFILTER1;
  break;
 default:
  WARN_ON(1);
  return;
 }

 CS_UNLOCK(drvdata->base);

 /* disable the flow of ATB data through port */
 writel_relaxed(0xff, drvdata->base + reg);

 if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0xff) &&
     (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0xff))
  coresight_disclaim_device_unlocked(csdev);
 CS_LOCK(drvdata->base);
}

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

 raw_spin_lock_irqsave(&drvdata->spinlock, flags);
 if (--out->src_refcnt == 0) {
  if (drvdata->base)
   dynamic_replicator_disable(drvdata, in->dest_port,
         out->src_port);
  last_disable = true;
 }
 raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);

 if (last_disable)
  dev_dbg(&csdev->dev, "REPLICATOR disabled\n");
}

static const struct coresight_ops_link replicator_link_ops = {
 .enable  = replicator_enable,
 .disable = replicator_disable,
};

static const struct coresight_ops replicator_cs_ops = {
 .link_ops = &replicator_link_ops,
};

static struct attribute *replicator_mgmt_attrs[] = {
 coresight_simple_reg32(idfilter0, REPLICATOR_IDFILTER0),
 coresight_simple_reg32(idfilter1, REPLICATOR_IDFILTER1),
 NULL,
};

static const struct attribute_group replicator_mgmt_group = {
 .attrs = replicator_mgmt_attrs,
 .name = "mgmt",
};

static const struct attribute_group *replicator_groups[] = {
 &replicator_mgmt_group,
 NULL,
};

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

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

 desc.name = coresight_alloc_device_name(&replicator_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-replicator, 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 = replicator_groups;
  desc.access = CSDEV_ACCESS_IOMEM(base);
  coresight_clear_self_claim_tag(&desc.access);
 }

 if (fwnode_property_present(dev_fwnode(dev),
        "qcom,replicator-loses-context"))
  drvdata->check_idfilter_val = true;

 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_SPLIT;
 desc.ops = &replicator_cs_ops;
 desc.pdata = dev->platform_data;
 desc.dev = dev;

 drvdata->csdev = coresight_register(&desc);
 if (IS_ERR(drvdata->csdev))
  return PTR_ERR(drvdata->csdev);

 replicator_reset(drvdata);
 return 0;
}

static int replicator_remove(struct device *dev)
{
 struct replicator_drvdata *drvdata = dev_get_drvdata(dev);

 coresight_unregister(drvdata->csdev);
 return 0;
}

static int replicator_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 = replicator_probe(&pdev->dev, res);
 pm_runtime_put(&pdev->dev);
 if (ret)
  pm_runtime_disable(&pdev->dev);

 return ret;
}

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

 if (WARN_ON(!drvdata))
  return;

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

#ifdef CONFIG_PM
static int replicator_runtime_suspend(struct device *dev)
{
 struct replicator_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 replicator_runtime_resume(struct device *dev)
{
 struct replicator_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 replicator_dev_pm_ops = {
 SET_RUNTIME_PM_OPS(replicator_runtime_suspend,
      replicator_runtime_resume, NULL)
};

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

MODULE_DEVICE_TABLE(of, replicator_match);

#ifdef CONFIG_ACPI
static const struct acpi_device_id replicator_acpi_ids[] = {
 {"ARMHC985", 0, 0, 0}, /* ARM CoreSight Static Replicator */
 {"ARMHC98D", 0, 0, 0}, /* ARM CoreSight Dynamic Replicator */
 {}
};

MODULE_DEVICE_TABLE(acpi, replicator_acpi_ids);
#endif

static struct platform_driver replicator_driver = {
 .probe          = replicator_platform_probe,
 .remove         = replicator_platform_remove,
 .driver         = {
  .name   = "coresight-replicator",
  /* THIS_MODULE is taken care of by platform_driver_register() */
  .of_match_table = of_match_ptr(replicator_match),
  .acpi_match_table = ACPI_PTR(replicator_acpi_ids),
  .pm = &replicator_dev_pm_ops,
  .suppress_bind_attrs = true,
 },
};

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

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

 return ret;
}

static void dynamic_replicator_remove(struct amba_device *adev)
{
 replicator_remove(&adev->dev);
}

static const struct amba_id dynamic_replicator_ids[] = {
 CS_AMBA_ID(0x000bb909),
 CS_AMBA_ID(0x000bb9ec),  /* Coresight SoC-600 */
 {},
};

MODULE_DEVICE_TABLE(amba, dynamic_replicator_ids);

static struct amba_driver dynamic_replicator_driver = {
 .drv = {
  .name = "coresight-dynamic-replicator",
  .pm = &replicator_dev_pm_ops,
  .suppress_bind_attrs = true,
 },
 .probe  = dynamic_replicator_probe,
 .remove         = dynamic_replicator_remove,
 .id_table = dynamic_replicator_ids,
};

static int __init replicator_init(void)
{
 return coresight_init_driver("replicator", &dynamic_replicator_driver, &replicator_driver,
         THIS_MODULE);
}

static void __exit replicator_exit(void)
{
 coresight_remove_driver(&dynamic_replicator_driver, &replicator_driver);
}

module_init(replicator_init);
module_exit(replicator_exit);

MODULE_AUTHOR("Pratik Patel ");
MODULE_AUTHOR("Mathieu Poirier ");
MODULE_DESCRIPTION("Arm CoreSight Replicator Driver");
MODULE_LICENSE("GPL v2");