acpi: Remove ETM from AMBA scan list (was Re: [PATCH V6 6/6] coresight: etm4x: Add ACPI support in platform driver)

[Suzuki K Poulose <suzuki.poulose@arm.com>]

Hi Rafael/Len

On 19/07/2023 11:11, Suzuki K Poulose wrote:
> Rafael, Len
> 
> Ping (packets 6, lost 100%).
> 
> 
> On 10/07/2023 17:40, Suzuki K Poulose wrote:
>> Rafael, Len
>>
>> On 10/07/2023 07:25, Anshuman Khandual wrote:
>>> From: Suzuki K Poulose <suzuki.poulose@arm.com>
>>>
>>> Drop ETM4X ACPI ID from the AMBA ACPI device list, and instead just 
>>> move it
>>> inside the new ACPI devices list detected and used via platform driver.
>>>
>>> Cc: "Rafael J. Wysocki" <rafael@kernel.org>
>>> Cc: Len Brown <lenb@kernel.org>
>>> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
>>> Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
>>> Cc: Mike Leach <mike.leach@linaro.org>
>>> Cc: Leo Yan <leo.yan@linaro.org>
>>> Cc: Sudeep Holla <sudeep.holla@arm.com>
>>> Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
>>> Cc: linux-acpi@vger.kernel.org
>>> Cc: coresight@lists.linaro.org
>>> Cc: linux-arm-kernel@lists.infradead.org
>>> Cc: linux-kernel@vger.kernel.org
>>> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> (for ACPI specific 
>>> changes)
>>> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
>>> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
>>
>> We would like to queue this via coresight tree. The acpi_amba bits have
>> been reviewed by Sudeep. Please could you give us an Ack, if you are
>> happy with the proposal ?
>>

Please could one of you respond to this patch ? We are blocked on your 
Ack for queuing this. There are machines out there, which rely on this
patch to use Arm self-hosted tracing based on CoreSight.

Kind regards
Suzuki

> 
> Kind regards
> Suzuki
> 
>> Kind regards
>> Suzuki
>>
>>
>>> ---
>>>   drivers/acpi/acpi_amba.c                           |  1 -
>>>   drivers/hwtracing/coresight/coresight-etm4x-core.c | 10 ++++++++++
>>>   2 files changed, 10 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/acpi/acpi_amba.c b/drivers/acpi/acpi_amba.c
>>> index f5b443ab01c2..099966cbac5a 100644
>>> --- a/drivers/acpi/acpi_amba.c
>>> +++ b/drivers/acpi/acpi_amba.c
>>> @@ -22,7 +22,6 @@
>>>   static const struct acpi_device_id amba_id_list[] = {
>>>       {"ARMH0061", 0}, /* PL061 GPIO Device */
>>>       {"ARMH0330", 0}, /* ARM DMA Controller DMA-330 */
>>> -    {"ARMHC500", 0}, /* ARM CoreSight ETM4x */
>>>       {"ARMHC501", 0}, /* ARM CoreSight ETR */
>>>       {"ARMHC502", 0}, /* ARM CoreSight STM */
>>>       {"ARMHC503", 0}, /* ARM CoreSight Debug */
>>> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c 
>>> b/drivers/hwtracing/coresight/coresight-etm4x-core.c
>>> index 43f583987250..703b6fcbb6a5 100644
>>> --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
>>> +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
>>> @@ -3,6 +3,7 @@
>>>    * Copyright (c) 2014, The Linux Foundation. All rights reserved.
>>>    */
>>> +#include <linux/acpi.h>
>>>   #include <linux/bitops.h>
>>>   #include <linux/kernel.h>
>>>   #include <linux/moduleparam.h>
>>> @@ -2347,12 +2348,21 @@ static const struct of_device_id 
>>> etm4_sysreg_match[] = {
>>>       {}
>>>   };
>>> +#ifdef CONFIG_ACPI
>>> +static const struct acpi_device_id etm4x_acpi_ids[] = {
>>> +    {"ARMHC500", 0}, /* ARM CoreSight ETM4x */
>>> +    {}
>>> +};
>>> +MODULE_DEVICE_TABLE(acpi, etm4x_acpi_ids);
>>> +#endif
>>> +
>>>   static struct platform_driver etm4_platform_driver = {
>>>       .probe        = etm4_probe_platform_dev,
>>>       .remove        = etm4_remove_platform_dev,
>>>       .driver            = {
>>>           .name            = "coresight-etm4x",
>>>           .of_match_table        = etm4_sysreg_match,
>>> +        .acpi_match_table    = ACPI_PTR(etm4x_acpi_ids),
>>>           .suppress_bind_attrs    = true,
>>>           .pm            = &etm4_dev_pm_ops,
>>>       },
>>
>