Re: [PATCH v2 1/2] coresight: replicator: Add Qualcomm CoreSight Replicator driver

[Mathieu Poirier <mathieu.poirier@linaro.org>]

On 7 May 2015 at 09:36, Ivan T. Ivanov <ivan.ivanov@linaro.org> wrote:
> From: Pratik Patel <pratikp@codeaurora.org>
>
> This driver manages Qualcomm CoreSight Replicator device, which
> resides on the AMBA bus. Replicator has been made programmable to
> allow software to turn of the replicator branch to sink that is not
> being used. This avoids trace traffic to the unused/non-current sink
> from causing back pressure that results in overflows at the source.
>
> Signed-off-by: Pratik Patel <pratikp@codeaurora.org>
> Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
> ---
>  .../devicetree/bindings/arm/coresight.txt          |   1 +
>  drivers/hwtracing/coresight/Kconfig                |   8 +
>  drivers/hwtracing/coresight/Makefile               |   1 +
>  .../coresight/coresight-replicator-qcom.c          | 214 +++++++++++++++++++++
>  4 files changed, 224 insertions(+)
>  create mode 100644 drivers/hwtracing/coresight/coresight-replicator-qcom.c
>
> diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt
> index f4d6a86..661a1be 100644
> --- a/Documentation/devicetree/bindings/arm/coresight.txt
> +++ b/Documentation/devicetree/bindings/arm/coresight.txt
> @@ -18,6 +18,7 @@ its hardware characteristcs.
>                 - "arm,coresight-funnel", "arm,primecell";
>                 - "arm,coresight-etm3x", "arm,primecell";
>                 - "arm,coresight-etm4x", "arm,primecell";
> +               - "qcom,coresight-replicator1x", "arm,primecell";
>
>         * reg: physical base address and length of the register
>           set(s) of the component.
> diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
> index 6b331d4..a57a51d 100644
> --- a/drivers/hwtracing/coresight/Kconfig
> +++ b/drivers/hwtracing/coresight/Kconfig
> @@ -68,4 +68,12 @@ config CORESIGHT_SOURCE_ETM4X
>           instructions that a processor is executing. This is primarily useful
>           for instruction level tracing. Depending on the implemented version
>           data tracing may also be available.
> +
> +config CORESIGHT_QCOM_REPLICATOR
> +       bool "Qualcomm CoreSight Replicator driver"
> +       help
> +         This enables support for Qualcomm CoreSight link driver. The programmable
> +         ATB replicator sends the ATB trace stream from the ETB/ETF to the TPIU
> +         and ETR.
> +
>  endif
> diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
> index 0af28d4..99f8e5f 100644
> --- a/drivers/hwtracing/coresight/Makefile
> +++ b/drivers/hwtracing/coresight/Makefile
> @@ -10,3 +10,4 @@ obj-$(CONFIG_CORESIGHT_LINKS_AND_SINKS) += coresight-funnel.o \
>                                            coresight-replicator.o
>  obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o coresight-etm-cp14.o
>  obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o
> +obj-$(CONFIG_CORESIGHT_QCOM_REPLICATOR) += coresight-replicator-qcom.o
> diff --git a/drivers/hwtracing/coresight/coresight-replicator-qcom.c b/drivers/hwtracing/coresight/coresight-replicator-qcom.c
> new file mode 100644
> index 0000000..deacea4
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-replicator-qcom.c
> @@ -0,0 +1,214 @@
> +/*
> + * Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/amba/bus.h>
> +#include <linux/clk.h>
> +#include <linux/coresight.h>
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/of.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/slab.h>
> +
> +#include "coresight-priv.h"
> +
> +#define REPLICATOR_IDFILTER0           0x000
> +#define REPLICATOR_IDFILTER1           0x004
> +
> +/**
> + * struct replicator_state - specifics associated to a replicator component
> + * @base:      memory mapped base address for this component.
> + * @dev:       the device entity associated with this component
> + * @atclk:     optional clock for the core parts of the replicator.
> + * @csdev:     component vitals needed by the framework
> + */
> +struct replicator_state {
> +       void __iomem            *base;
> +       struct device           *dev;
> +       struct clk              *atclk;
> +       struct coresight_device *csdev;
> +};
> +
> +static int replicator_enable(struct coresight_device *csdev, int inport,
> +                             int outport)
> +{
> +       struct replicator_state *drvdata = dev_get_drvdata(csdev->dev.parent);
> +
> +       pm_runtime_get_sync(drvdata->dev);
> +
> +       CS_UNLOCK(drvdata->base);
> +
> +       /*
> +        * Ensure that the other port is disabled
> +        * 0x00 - passing through the replicator unimpeded
> +        * 0xff - disable (or impede) the flow of ATB data
> +        */
> +       if (outport == 0) {
> +               writel_relaxed(0x00, drvdata->base + REPLICATOR_IDFILTER0);
> +               writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
> +       } else {
> +               writel_relaxed(0x00, drvdata->base + REPLICATOR_IDFILTER1);
> +               writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
> +       }
> +
> +       CS_LOCK(drvdata->base);
> +
> +       dev_info(drvdata->dev, "REPLICATOR enabled\n");
> +       return 0;
> +}
> +
> +static void replicator_disable(struct coresight_device *csdev, int inport,
> +                               int outport)
> +{
> +       struct replicator_state *drvdata = dev_get_drvdata(csdev->dev.parent);
> +
> +       CS_UNLOCK(drvdata->base);
> +
> +       /* disable the flow of ATB data through port */
> +       if (outport == 0)
> +               writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
> +       else
> +               writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
> +
> +       CS_LOCK(drvdata->base);
> +
> +       pm_runtime_put(drvdata->dev);
> +
> +       dev_info(drvdata->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 int replicator_probe(struct amba_device *adev, const struct amba_id *id)
> +{
> +       int ret;
> +       struct device *dev = &adev->dev;
> +       struct resource *res = &adev->res;
> +       struct coresight_platform_data *pdata = NULL;
> +       struct replicator_state *drvdata;
> +       struct coresight_desc *desc;
> +       struct device_node *np = adev->dev.of_node;
> +       void __iomem *base;
> +
> +       if (np) {
> +               pdata = of_get_coresight_platform_data(dev, np);
> +               if (IS_ERR(pdata))
> +                       return PTR_ERR(pdata);
> +               adev->dev.platform_data = pdata;
> +       }
> +
> +       drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
> +       if (!drvdata)
> +               return -ENOMEM;
> +
> +       drvdata->dev = &adev->dev;
> +       drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
> +       if (!IS_ERR(drvdata->atclk)) {
> +               ret = clk_prepare_enable(drvdata->atclk);
> +               if (ret)
> +                       return ret;
> +       }
> +
> +       /* Validity for the resource is already checked by the AMBA core */
> +       base = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(base))
> +               return PTR_ERR(base);
> +
> +       drvdata->base = base;
> +       dev_set_drvdata(dev, drvdata);
> +       pm_runtime_put(&adev->dev);
> +
> +       desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
> +       if (!desc)
> +               return -ENOMEM;
> +
> +       desc->type = CORESIGHT_DEV_TYPE_LINK;
> +       desc->subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT;
> +       desc->ops = &replicator_cs_ops;
> +       desc->pdata = adev->dev.platform_data;
> +       desc->dev = &adev->dev;
> +       drvdata->csdev = coresight_register(desc);
> +       if (IS_ERR(drvdata->csdev))
> +               return PTR_ERR(drvdata->csdev);
> +
> +       dev_info(dev, "%s initialized\n", (char *)id->data);
> +       return 0;
> +}
> +
> +static int replicator_remove(struct amba_device *adev)
> +{
> +       struct replicator_state *drvdata = amba_get_drvdata(adev);
> +
> +       pm_runtime_disable(&adev->dev);
> +       coresight_unregister(drvdata->csdev);
> +       return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int replicator_runtime_suspend(struct device *dev)
> +{
> +       struct replicator_state *drvdata = dev_get_drvdata(dev);
> +
> +       if (drvdata && !IS_ERR(drvdata->atclk))
> +               clk_disable_unprepare(drvdata->atclk);
> +
> +       return 0;
> +}
> +
> +static int replicator_runtime_resume(struct device *dev)
> +{
> +       struct replicator_state *drvdata = dev_get_drvdata(dev);
> +
> +       if (drvdata && !IS_ERR(drvdata->atclk))
> +               clk_prepare_enable(drvdata->atclk);
> +
> +       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 struct amba_id replicator_ids[] = {
> +       {
> +               .id     = 0x0003b909,
> +               .mask   = 0x0003ffff,
> +               .data   = "REPLICATOR 1.0",
> +       },
> +       { 0, 0 },
> +};
> +
> +static struct amba_driver replicator_driver = {
> +       .drv = {
> +               .name   = "coresight-replicator-qcom",
> +               .pm     = &replicator_dev_pm_ops,
> +       },
> +       .probe          = replicator_probe,
> +       .remove         = replicator_remove,
> +       .id_table       = replicator_ids,
> +};
> +
> +module_amba_driver(replicator_driver);
> --
> 1.9.1
>

Applied - thanks.