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Message-ID: <00e8622a-915b-b5e0-12cd-78bb6a2758c9@quicinc.com>
Date:   Tue, 5 Jul 2022 10:35:51 +0530
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Subject: Re: [PATCHv2] iommu/arm-smmu-qcom: Add debug support for TLB sync
 timeouts
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From:   Sai Prakash Ranjan <quic_saipraka@quicinc.com>
To:     Will Deacon <will@kernel.org>, Robin Murphy <robin.murphy@arm.com>,
        "Joerg Roedel" <joro@8bytes.org>
CC:     <iommu@lists.linux-foundation.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <linux-arm-msm@vger.kernel.org>,
        <quic_guptap@quicinc.com>, Rob Clark <robdclark@chromium.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>
References: <20220526041403.9984-1-quic_saipraka@quicinc.com>
 <21d5fc44-4870-02bb-70b4-d9e1188c9cc1@quicinc.com>
In-Reply-To: <21d5fc44-4870-02bb-70b4-d9e1188c9cc1@quicinc.com>
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On 6/23/2022 11:32 AM, Sai Prakash Ranjan wrote:
> On 5/26/2022 9:44 AM, Sai Prakash Ranjan wrote:
>> TLB sync timeouts can be due to various reasons such as TBU power down
>> or pending TCU/TBU invalidation/sync and so on. Debugging these often
>> require dumping of some implementation defined registers to know the
>> status of TBU/TCU operations and some of these registers are not
>> accessible in non-secure world such as from kernel and requires SMC
>> calls to read them in the secure world. So, add this debug support
>> to dump implementation defined registers for TLB sync timeout issues.
>>
>> Signed-off-by: Sai Prakash Ranjan <quic_saipraka@quicinc.com>
>> ---
>>
>> Changes in v2:
>>   * Use scm call consistently so that it works on older chipsets where
>>     some of these regs are secure registers.
>>   * Add device specific data to get the implementation defined register
>>     offsets.
>>
>> ---
>>   drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 161 ++++++++++++++++++---
>>   drivers/iommu/arm/arm-smmu/arm-smmu.c      |   2 +
>>   drivers/iommu/arm/arm-smmu/arm-smmu.h      |   1 +
>>   3 files changed, 146 insertions(+), 18 deletions(-)
>
> Any comments on this patch?

Gentle Ping !!

Thanks,
Sai