Re: [PATCH 5/7] coresight: tmc: Move ACPI support from AMBA driver to platform driver

[Suzuki K Poulose]

On 22/11/2023 17:04, Sudeep Holla wrote:
> On Fri, Oct 27, 2023 at 12:59:41PM +0530, Anshuman Khandual wrote:
> > Add support for the tmc devices in the platform driver, which can then be
> > used on ACPI based platforms. This change would now allow runtime power
> > management for ACPI based systems. The driver would try to enable the APB
> > clock if available.
> >
> > Cc: Lorenzo Pieralisi <lpieralisi@xxxxxxxxxx>
> > Cc: Sudeep Holla <sudeep.holla@xxxxxxx>
> > Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> > Cc: Mike Leach <mike.leach@xxxxxxxxxx>
> > Cc: James Clark <james.clark@xxxxxxx>
> > Cc: linux-acpi@xxxxxxxxxxxxxxx
> > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> > Cc: linux-kernel@xxxxxxxxxxxxxxx
> > Cc: coresight@xxxxxxxxxxxxxxxx
> > Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> > ---
> >   drivers/acpi/arm64/amba.c                     |   2 -
> >   .../hwtracing/coresight/coresight-tmc-core.c  | 127 +++++++++++++++---
> >   drivers/hwtracing/coresight/coresight-tmc.h   |   1 +
> >   3 files changed, 113 insertions(+), 17 deletions(-)
>
> [...]
>
> > diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
> > index 7ec5365e2b64..618bc0b7a1a5 100644
> > --- a/drivers/hwtracing/coresight/coresight-tmc-core.c
> > +++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
>
> [...]
>
> > @@ -573,9 +579,9 @@ static void tmc_shutdown(struct amba_device *adev)
> >   	spin_unlock_irqrestore(&drvdata->spinlock, flags);
> >   }
> >   
> > -static void tmc_remove(struct amba_device *adev)
> > +static void __tmc_remove(struct device *dev)
> >   {
> > -	struct tmc_drvdata *drvdata = dev_get_drvdata(&adev->dev);
> > +	struct tmc_drvdata *drvdata = dev_get_drvdata(dev);
> >   
> >   	/*
> >   	 * Since misc_open() holds a refcount on the f_ops, which is
> > @@ -586,6 +592,11 @@ static void tmc_remove(struct amba_device *adev)
> >   	coresight_unregister(drvdata->csdev);
> >   }
> >   
> > +static void tmc_remove(struct amba_device *adev)
> > +{
> > +	__tmc_remove(&adev->dev);
> > +}
> > +
> >   static const struct amba_id tmc_ids[] = {
> >   	CS_AMBA_ID(0x000bb961),
> >   	/* Coresight SoC 600 TMC-ETR/ETS */
> > @@ -613,6 +624,92 @@ static struct amba_driver tmc_driver = {
> >   
> >   module_amba_driver(tmc_driver);
> >   
> > +static int tmc_platform_probe(struct platform_device *pdev)
> > +{
> > +	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	struct tmc_drvdata *drvdata;
> > +	int ret = 0;
> > +
> > +	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
> > +	if (!drvdata)
> > +		return -ENOMEM;
> > +
> > +	drvdata->pclk = coresight_get_enable_apb_pclk(&pdev->dev);
> > +	if (IS_ERR(drvdata->pclk))
> > +		return -ENODEV;
> > +
>
> --->8
> > +	if (res) {
> > +		drvdata->base = devm_ioremap_resource(&pdev->dev, res);
> > +		if (IS_ERR(drvdata->base)) {
> > +			clk_put(drvdata->pclk);
> > +			return PTR_ERR(drvdata->base);
> > +		}
> > +	}
> > +
> ---
>
> You need drop the above hunk as _tmc_probe() already takes care of that.
> This is the root cause for the issue I reported in the other thread. Also
> sorry for the confusion, I had to refer to coresight-tmc-core.c and post
> the patch to unify module_init/exit but completely mixed up the file/patch
> and referred coresight-tpiu-core.c instead as that patch was dealing with
> it.

Thank you Sudeep for getting to the bottom of the problem !

Suzuki
>