On 9/12/2023 2:56 PM, Mukesh Ojha wrote:
> Thanks for your time in reviewing this.
>
> On 9/11/2023 4:31 PM, Krzysztof Kozlowski wrote:
>> On 09/09/2023 22:16, Mukesh Ojha wrote:
>>> Minidump is a best effort mechanism to collect useful and predefined
>>> data for first level of debugging on end user devices running on
>>> Qualcomm SoCs. It is built on the premise that System on Chip (SoC)
>>> or subsystem part of SoC crashes, due to a range of hardware and
>>> software bugs. Hence, the ability to collect accurate data is only
>>> a best-effort. The data collected could be invalid or corrupted,
>>> data collection itself could fail, and so on.
>>
>> ...
>>
>>> +static int qcom_apss_md_table_init(struct minidump *md,
>>> + struct minidump_subsystem *mdss_toc)
>>> +{
>>> + struct minidump_ss_data *mdss_data;
>>> +
>>> + mdss_data = devm_kzalloc(md->dev, sizeof(*mdss_data), GFP_KERNEL);
>>> + if (!mdss_data)
>>> + return -ENOMEM;
>>> +
>>> + mdss_data->md_ss_toc = mdss_toc;
>>> + mdss_data->md_regions = devm_kcalloc(md->dev, MAX_NUM_ENTRIES,
>>> + sizeof(struct minidump_region),
>>> + GFP_KERNEL);
>>> + if (!mdss_data->md_regions)
>>> + return -ENOMEM;
>>> +
>>> + mdss_toc = mdss_data->md_ss_toc;
>>> + mdss_toc->regions_baseptr =
>>> cpu_to_le64(virt_to_phys(mdss_data->md_regions));
>>> + mdss_toc->enabled = cpu_to_le32(MINIDUMP_SS_ENABLED);
>>> + mdss_toc->status = cpu_to_le32(1);
>>> + mdss_toc->region_count = cpu_to_le32(0);
>>> +
>>> + /* Tell bootloader not to encrypt the regions of this subsystem */
>>> + mdss_toc->encryption_status = cpu_to_le32(MINIDUMP_SS_ENCR_DONE);
>>> + mdss_toc->encryption_required =
>>> cpu_to_le32(MINIDUMP_SS_ENCR_NOTREQ);
>>> +
>>> + md->apss_data = mdss_data;
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int qcom_apss_minidump_probe(struct platform_device *pdev)
>>> +{
>>> + struct minidump_global_toc *mdgtoc;
>>> + struct minidump *md;
>>> + size_t size;
>>> + int ret;
>>> +
>>> + md = devm_kzalloc(&pdev->dev, sizeof(struct minidump), GFP_KERNEL);
>>
>> sizeof(*)
>>
>> Didn't you get such comments already?
>
> Ok, will fix this, no i have not got such comments as of yet.
> Any reason of using this way?
Got the reason, thanks.
-Mukesh
>
>>
>>
>>> + if (!md)
>>> + return -ENOMEM;
>>> +
>>> + md->dev = &pdev->dev;
>>> + mdgtoc = qcom_smem_get(QCOM_SMEM_HOST_ANY, SBL_MINIDUMP_SMEM_ID,
>>> &size);
>>> + if (IS_ERR(mdgtoc)) {
>>> + ret = PTR_ERR(mdgtoc);
>>> + dev_err(md->dev, "Couldn't find minidump smem item: %d\n",
>>> ret);
>>> + return ret;
>>
>> The syntax is:
>> return dev_err_probe
>
> ACK.
>
>>
>>> + }
>>> +
>>> + if (size < sizeof(*mdgtoc) || !mdgtoc->status) {
>>> + dev_err(md->dev, "minidump table is not initialized: %d\n",
>>> ret);
>>
>> ret is uninitialized here. Please use automated tools for checking your
>> code:
>> coccinelle, smatch and sparse
>
> Thanks.
>
>>
>>> + return -EINVAL;
>>> + }
>>> +
>>> + mutex_init(&md->md_lock);
>>> + ret = qcom_apss_md_table_init(md,
>>> &mdgtoc->subsystems[MINIDUMP_APSS_DESC]);
>>> + if (ret) {
>>> + dev_err(md->dev, "apss minidump initialization failed:
>>> %d\n", ret);
>>> + return ret;
>>> + }
>>> +
>>> + /* First entry would be ELF header */
>>> + ret = qcom_md_add_elfheader(md);
>>> + if (ret) {
>>> + dev_err(md->dev, "Failed to add elf header: %d\n", ret);
>>> + memset(md->apss_data->md_ss_toc, 0, sizeof(struct
>>> minidump_subsystem));
>>
>> Why do you need it?
>
> Earlier, i got comment about clearing the SS TOC(subsystem table of
> content) which is shared with other SS and it will have stale values.
>
>>
>>> + return ret;
>>> + }
>>> +
>>> + platform_set_drvdata(pdev, md);
>>> +
>>> + return ret;
>>> +}
>>> +
>>> +static int qcom_apss_minidump_remove(struct platform_device *pdev)
>>> +{
>>> + struct minidump *md = platform_get_drvdata(pdev);
>>> + struct minidump_ss_data *mdss_data;
>>> +
>>> + mdss_data = md->apss_data;
>>> + memset(mdss_data->md_ss_toc, cpu_to_le32(0), sizeof(struct
>>> minidump_subsystem));
>>
>> Why do you need it?
>
> Same as above.
>
>>
>>> + md = NULL;
>>
>> That's useless assignment.
>
> Ok.
>
>>
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static struct platform_driver qcom_minidump_driver = {
>>> + .probe = qcom_apss_minidump_probe,
>>> + .remove = qcom_apss_minidump_remove,
>>> + .driver = {
>>> + .name = "qcom-minidump-smem",
>>> + },
>>> +};
>>> +
>>> +module_platform_driver(qcom_minidump_driver);
>>> +
>>> +MODULE_DESCRIPTION("Qualcomm APSS minidump driver");
>>> +MODULE_LICENSE("GPL");
>>> +MODULE_ALIAS("platform:qcom-minidump-smem");
>>
>> Add a proper ID table instead of re-inventing it with module aliases.
>
> Ok.
>
> -Mukesh
>
>>
>> Best regards,
>> Krzysztof
>>