-----Original Message-----
From: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Sent: Monday, January 10, 2022 6:59 PM
To: Sajida Bhanu (Temp) (QUIC) <quic_c_sbhanu@xxxxxxxxxxx>; riteshh@xxxxxxxxxxxxxx; Asutosh Das (asd) <asutoshd@xxxxxxxxxxx>; ulf.hansson@xxxxxxxxxx; agross@xxxxxxxxxx; bjorn.andersson@xxxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx; linux-arm-msm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
Cc: stummala@xxxxxxxxxxxxxx; vbadigan@xxxxxxxxxxxxxx; Ram Prakash Gupta (QUIC) <quic_rampraka@xxxxxxxxxxx>; Pradeep Pragallapati (QUIC) <quic_pragalla@xxxxxxxxxxx>; sartgarg@xxxxxxxxxxxxxx; nitirawa@xxxxxxxxxxxxxx; sayalil@xxxxxxxxxxxxxx
Subject: Re: [PATCH V2] mmc: debugfs: add error statistics
On 10/01/2022 15:11, Sajida Bhanu (Temp) (QUIC) wrote:
> Hi Adrian,
>
> Thanks for the review.
>
> Please find the inline comments
>
> Thanks,
> Sajida
>
> -----Original Message-----
> From: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> Sent: Friday, January 7, 2022 1:13 PM
> To: Sajida Bhanu (Temp) (QUIC) <quic_c_sbhanu@xxxxxxxxxxx>;
> riteshh@xxxxxxxxxxxxxx; Asutosh Das (asd) <asutoshd@xxxxxxxxxxx>;
> ulf.hansson@xxxxxxxxxx; agross@xxxxxxxxxx; bjorn.andersson@xxxxxxxxxx;
> linux-mmc@xxxxxxxxxxxxxxx; linux-arm-msm@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx
> Cc: stummala@xxxxxxxxxxxxxx; vbadigan@xxxxxxxxxxxxxx; Ram Prakash
> Gupta (QUIC) <quic_rampraka@xxxxxxxxxxx>; Pradeep Pragallapati (QUIC)
> <quic_pragalla@xxxxxxxxxxx>; sartgarg@xxxxxxxxxxxxxx;
> nitirawa@xxxxxxxxxxxxxx; sayalil@xxxxxxxxxxxxxx
> Subject: Re: [PATCH V2] mmc: debugfs: add error statistics
>
> On 04/01/2022 17:02, Sajida Bhanu (Temp) (QUIC) wrote:
>> Hi Adrian,
>>
>> Thanks for the review.
>>
>> Please find the inline comments.
>>
>> Thanks,
>> Sajida
>>
>> -----Original Message-----
>> From: Adrian Hunter <adrian.hunter@xxxxxxxxx>
>> Sent: Monday, January 3, 2022 3:20 PM
>> To: Sajida Bhanu (Temp) (QUIC) <quic_c_sbhanu@xxxxxxxxxxx>;
>> riteshh@xxxxxxxxxxxxxx; Asutosh Das (asd) <asutoshd@xxxxxxxxxxx>;
>> ulf.hansson@xxxxxxxxxx; agross@xxxxxxxxxx;
>> bjorn.andersson@xxxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx;
>> linux-arm-msm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
>> Cc: stummala@xxxxxxxxxxxxxx; vbadigan@xxxxxxxxxxxxxx; Ram Prakash
>> Gupta (QUIC) <quic_rampraka@xxxxxxxxxxx>; Pradeep Pragallapati (QUIC)
>> <quic_pragalla@xxxxxxxxxxx>; sartgarg@xxxxxxxxxxxxxx;
>> nitirawa@xxxxxxxxxxxxxx; sayalil@xxxxxxxxxxxxxx
>> Subject: Re: [PATCH V2] mmc: debugfs: add error statistics
>>
>> On 21/12/2021 09:16, Sajida Bhanu (Temp) (QUIC) wrote:
>>> Hi Adrian,
>>>
>>> Thanks for the review.
>>>
>>> Please find the inline comments.
>>
>> I find the way the inline comments are done a bit difficult to follow, since what I wrote is not quoted, and what you wrote is quoted. Normally it is the other way around.
>>
>>>
>>> Thanks,
>>> Sajida
>>>
>>> -----Original Message-----
>>> From: Adrian Hunter <adrian.hunter@xxxxxxxxx>
>>> Sent: Wednesday, December 15, 2021 7:33 PM
>>> To: Sajida Bhanu (Temp) (QUIC) <quic_c_sbhanu@xxxxxxxxxxx>;
>>> riteshh@xxxxxxxxxxxxxx; Asutosh Das (asd) <asutoshd@xxxxxxxxxxx>;
>>> ulf.hansson@xxxxxxxxxx; agross@xxxxxxxxxx;
>>> bjorn.andersson@xxxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx;
>>> linux-arm-msm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
>>> Cc: stummala@xxxxxxxxxxxxxx; vbadigan@xxxxxxxxxxxxxx; Ram Prakash
>>> Gupta (QUIC) <quic_rampraka@xxxxxxxxxxx>; Pradeep Pragallapati
>>> (QUIC) <quic_pragalla@xxxxxxxxxxx>; sartgarg@xxxxxxxxxxxxxx;
>>> nitirawa@xxxxxxxxxxxxxx; sayalil@xxxxxxxxxxxxxx
>>> Subject: Re: [PATCH V2] mmc: debugfs: add error statistics
>>>
>>> On 14/12/2021 16:41, Shaik Sajida Bhanu wrote:
>>>> Add debugfs entry to query eMMC and SD card errors statistics.
>>>> This feature is useful for debug and testing
>>>>
>>>> Signed-off-by: Shaik Sajida Bhanu <quic_c_sbhanu@xxxxxxxxxxx>
>>>> ---
>>>>
>>>> Changes since V1:
>>>> -Removed sysfs entry for eMMC and SD card error statistics and added
>>>> debugfs entry as suggested by Adrian Hunter and Ulf Hansson.
>>>
>>> Thanks for doing this.
>>>
>>>> ---
>>>> drivers/mmc/core/debugfs.c | 106 +++++++++++++++++++++++++++++++++++++++++++++
>>>> drivers/mmc/core/queue.c | 2 +
>>>> drivers/mmc/host/sdhci.c | 53 ++++++++++++++++++-----
>>>> include/linux/mmc/host.h | 37 ++++++++++++++++
>>>> 4 files changed, 186 insertions(+), 12 deletions(-)
>>>>
>>>> diff --git a/drivers/mmc/core/debugfs.c
>>>> b/drivers/mmc/core/debugfs.c index 3fdbc80..40210c34 100644
>>>> --- a/drivers/mmc/core/debugfs.c
>>>> +++ b/drivers/mmc/core/debugfs.c
>>>> @@ -223,6 +223,107 @@ static int mmc_clock_opt_set(void *data, u64
>>>> val) DEFINE_DEBUGFS_ATTRIBUTE(mmc_clock_fops, mmc_clock_opt_get, mmc_clock_opt_set,
>>>> "%llu\n");
>>>>
>>>> +static int mmc_err_state_get(void *data, u64 *val) {
>>>> + struct mmc_host *host = data;
>>>> +
>>>> + if (!host)
>>>> + return -EINVAL;
>>>> +
>>>> + *val = host->err_state ? 1 : 0;
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int mmc_err_state_clear(void *data, u64 val) {
>>>> + struct mmc_host *host = data;
>>>> +
>>>> + if (!host)
>>>> + return -EINVAL;
>>>> +
>>>> + host->err_state = false;
>>>
>>> Is there much reason to disable err stats from userspace?
>>>
>>>>>>>> Yes , while debugging we can go and check err_state , It is false means no errors happened in driver level and true means errors happened in driver level and then we can go and check err_stats[] to know more on error details like data CRC , command CRC etc.
>>
>> That is not exectly how it is programmed. "err_state is false" means no errors have been recorded, not that no errors happended.
>>
>>>>>>>> If user wants to explicitly clear then he can use this.
>
> Seems over compilicated. A user can just diff the old and new values:
>
> cat /sys/kernel/debug/mmc0/err_stats > /tmp/old-stats ...later...
> cat /sys/kernel/debug/mmc0/err_stats > /tmp/new-stats diff
> /tmp/old-stats /tmp/new-stats mv /tmp/new-stats /tmp/old-stats
>
> I suggest just outputting the stats
>
>>>>>>>> Thanks for the suggestion Adrain.
> This way user has to call write to store the err_stats data to /tmp/old-stats and user has to call read to read /tmp/old-stats.
Only if you need to see what has changed
>
> And our idea is user call only read to get error stats info.
>
> Please suggest me which is okay.
Please let's start with just outputting the stats.
>>>>> Sure. Thanks for the suggestion.
>
> Thanks,
> Sajida
>
>>
>>>
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +DEFINE_SIMPLE_ATTRIBUTE(mmc_err_state, mmc_err_state_get,
>>>> + mmc_err_state_clear, "%llu\n");
>>>> +
>>>> +static int mmc_err_stats_show(struct seq_file *file, void *data) {
>>>> + struct mmc_host *host = (struct mmc_host *)file->private;
>>>> +
>>>> + if (!host)
>>>> + return -EINVAL;
>>>
>>> I was thinking we needed a way to determine whether stats were being collected because not all drivers would support it at least initially e.g.
>>>
>>> if (!host->err_stats_enabled) {
>>> seq_printf(file, "Not supported by driver\n");
>>> return 0;
>>> }
>>>
>>>>>>>>>> You mean declare another variable (err_stats_enabled) and enable it in probe?
>>
>> Yes, although it is not clear if this is the same as what you want from err_state, i.e. is err_state different from err_stats_enabled?
>>
>>>>>>> Yes, err_state and err_stats_enabled both are different. err_state will be set if any errors happened in driver level.
>> err_stats_enabled will be set if err_stats feature enabled, if any vendor wants to use err_stats feature they will set this err_stats_enabled in their vendor specific file.
>>
>>>
>>>> +
>>>> + seq_printf(file, "# Command Timeout Occurred:\t %d\n",
>>>> + host->err_stats[MMC_ERR_CMD_TIMEOUT]);
>>>
>>> Maybe put the descriptions in an array and iterate e.g.
>>>
>>> const char *desc[MMC_ERR_MAX] = {
>>> [MMC_ERR_CMD_TIMEOUT] = "Command Timeout Occurred",
>>> etc
>>> };
>>> int i;
>>>
>>> if (!host)
>>> return -EINVAL;
>>>
>>> for (i = 0; i < MMC_ERR_MAX; i++) {
>>> if (desc[i])
>>> seq_printf(file, "# %s:\t %d\n",
>>> desc[1], host->err_stats[i]);
>>> }
>>>
>>>>>>>>>> Sure
>>>
>>>> +
>>>> + seq_printf(file, "# Command CRC Errors Occurred:\t %d\n",
>>>> + host->err_stats[MMC_ERR_CMD_CRC]);
>>>> +
>>>> + seq_printf(file, "# Data Timeout Occurred:\t %d\n",
>>>> + host->err_stats[MMC_ERR_DAT_TIMEOUT]);
>>>> +
>>>> + seq_printf(file, "# Data CRC Errors Occurred:\t %d\n",
>>>> + host->err_stats[MMC_ERR_DAT_CRC]);
>>>> +
>>>> + seq_printf(file, "# Auto-Cmd Error Occurred:\t %d\n",
>>>> + host->err_stats[MMC_ERR_ADMA]);
>>>> +
>>>> + seq_printf(file, "# ADMA Error Occurred:\t %d\n",
>>>> + host->err_stats[MMC_ERR_ADMA]);
>>>> +
>>>> + seq_printf(file, "# Tuning Error Occurred:\t %d\n",
>>>> + host->err_stats[MMC_ERR_TUNING]);
>>>> +
>>>> + seq_printf(file, "# CMDQ RED Errors:\t\t %d\n",
>>>> + host->err_stats[MMC_ERR_CMDQ_RED]);
>>>> +
>>>> + seq_printf(file, "# CMDQ GCE Errors:\t\t %d\n",
>>>> + host->err_stats[MMC_ERR_CMDQ_GCE]);
>>>> +
>>>> + seq_printf(file, "# CMDQ ICCE Errors:\t\t %d\n",
>>>> + host->err_stats[MMC_ERR_CMDQ_ICCE]);
>>>> +
>>>> + seq_printf(file, "# Request Timedout:\t %d\n",
>>>> + host->err_stats[MMC_ERR_REQ_TIMEOUT]);
>>>> +
>>>> + seq_printf(file, "# CMDQ Request Timedout:\t %d\n",
>>>> + host->err_stats[MMC_ERR_CMDQ_REQ_TIMEOUT]);
>>>> +
>>>> + seq_printf(file, "# ICE Config Errors:\t\t %d\n",
>>>> + host->err_stats[MMC_ERR_ICE_CFG]);
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int mmc_err_stats_open(struct inode *inode, struct file
>>>> +*file) {
>>>> + return single_open(file, mmc_err_stats_show, inode->i_private); }
>>>> +
>>>> +static ssize_t mmc_err_stats_write(struct file *filp, const char __user *ubuf,
>>>> + size_t cnt, loff_t *ppos)
>>>> +{
>>>> + struct mmc_host *host = filp->f_mapping->host->i_private;
>>>> +
>>>> + if (!host)
>>>> + return -EINVAL;
>>>> +
>>>> + pr_debug("%s: Resetting MMC error statistics\n", __func__);
>>>> + memset(host->err_stats, 0, sizeof(host->err_stats));
>>>> +
>>>> + return cnt;
>>>> +}
>>>> +
>>>> +static const struct file_operations mmc_err_stats_fops = {
>>>> + .open = mmc_err_stats_open,
>>>> + .read = seq_read,
>>>> + .write = mmc_err_stats_write,
>>>> +};
>>>> +
>>>> void mmc_add_host_debugfs(struct mmc_host *host) {
>>>> struct dentry *root;
>>>> @@ -236,6 +337,11 @@ void mmc_add_host_debugfs(struct mmc_host *host)
>>>> debugfs_create_file_unsafe("clock", S_IRUSR | S_IWUSR, root, host,
>>>> &mmc_clock_fops);
>>>>
>>>> + debugfs_create_file("err_state", 0600, root, host,
>>>> + &mmc_err_state);
>>>> + debugfs_create_file("err_stats", 0600, root, host,
>>>> + &mmc_err_stats_fops);
>>>> +
>>>> #ifdef CONFIG_FAIL_MMC_REQUEST
>>>> if (fail_request)
>>>> setup_fault_attr(&fail_default_attr, fail_request); diff --git
>>>> a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c index
>>>> b15c034..5243929 100644
>>>> --- a/drivers/mmc/core/queue.c
>>>> +++ b/drivers/mmc/core/queue.c
>>>> @@ -100,6 +100,8 @@ static enum blk_eh_timer_return mmc_cqe_timed_out(struct request *req)
>>>> enum mmc_issue_type issue_type = mmc_issue_type(mq, req);
>>>> bool recovery_needed = false;
>>>>
>>>> + mmc_debugfs_err_stats_inc(host, MMC_ERR_CMDQ_REQ_TIMEOUT);
>>>> +
>>>> switch (issue_type) {
>>>> case MMC_ISSUE_ASYNC:
>>>> case MMC_ISSUE_DCMD:
>>>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
>>>
>>> I think the core changes should be a separate patch from sdhci.
>>> I would probably split into 4:
>>> mmc core
>>> mmc block driver
>>> cqhci driver
>>> sdhci driver
>>>
>>>>>>> Sure
>>>
>>>> index 07c6da1..d742051 100644
>>>> --- a/drivers/mmc/host/sdhci.c
>>>> +++ b/drivers/mmc/host/sdhci.c
>>>> @@ -113,6 +113,7 @@ void sdhci_dumpregs(struct sdhci_host *host)
>>>> if (host->ops->dump_vendor_regs)
>>>> host->ops->dump_vendor_regs(host);
>>>>
>>>> + mmc_debugfs_err_stats_enable(host->mmc);
>>>
>>> Why here and not in e.g. __sdhci_add_host() ?
>>>
>>>>>>> If any errors happened in driver level then we will call sdhci_dumpregs() right( err_state true means some errors happened in driver level ). So it is better to call mmc_debugfs_err_stats_enable() here.
>>
>> Registers are not dumped for most errors. Please move this to __sdhci_add_host().
>>
>>>>>> err_state is true means errors happened in driver level and for most of the errors we are dumping the registers, so I am thinking it is better to have this call in sdhci_dumpregs() only.
>>
>>>
>>>> SDHCI_DUMP("============================================\n");
>>>> }
>>>> EXPORT_SYMBOL_GPL(sdhci_dumpregs);
>>>> @@ -3159,6 +3160,7 @@ static void sdhci_timeout_timer(struct timer_list *t)
>>>> spin_lock_irqsave(&host->lock, flags);
>>>>
>>>> if (host->cmd && !sdhci_data_line_cmd(host->cmd)) {
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_REQ_TIMEOUT);
>>>> pr_err("%s: Timeout waiting for hardware cmd interrupt.\n",
>>>> mmc_hostname(host->mmc));
>>>> sdhci_dumpregs(host);
>>>> @@ -3181,6 +3183,7 @@ static void sdhci_timeout_data_timer(struct
>>>> timer_list *t)
>>>>
>>>> if (host->data || host->data_cmd ||
>>>> (host->cmd && sdhci_data_line_cmd(host->cmd))) {
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_REQ_TIMEOUT);
>>>> pr_err("%s: Timeout waiting for hardware interrupt.\n",
>>>> mmc_hostname(host->mmc));
>>>> sdhci_dumpregs(host);
>>>> @@ -3240,11 +3243,15 @@ static void sdhci_cmd_irq(struct sdhci_host
>>>> *host, u32 intmask, u32 *intmask_p)
>>>>
>>>> if (intmask & (SDHCI_INT_TIMEOUT | SDHCI_INT_CRC |
>>>> SDHCI_INT_END_BIT | SDHCI_INT_INDEX)) {
>>>> - if (intmask & SDHCI_INT_TIMEOUT)
>>>> + if (intmask & SDHCI_INT_TIMEOUT) {
>>>> host->cmd->error = -ETIMEDOUT;
>>>> - else
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_CMD_TIMEOUT);
>>>> + } else {
>>>> host->cmd->error = -EILSEQ;
>>>> -
>>>> + if (host->cmd->opcode != MMC_SEND_TUNING_BLOCK ||
>>>> + host->cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200)
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_CMD_CRC);
>>>> + }
>>>> /* Treat data command CRC error the same as data CRC error */
>>>> if (host->cmd->data &&
>>>> (intmask & (SDHCI_INT_CRC | SDHCI_INT_TIMEOUT)) == @@
>>>> -3266,6
>>>> +3273,7 @@ static void sdhci_cmd_irq(struct sdhci_host *host, u32
>>>> +intmask, u32 *intmask_p)
>>>> -ETIMEDOUT :
>>>> -EILSEQ;
>>>>
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_AUTO_CMD);
>>>> if (sdhci_auto_cmd23(host, mrq)) {
>>>> mrq->sbc->error = err;
>>>> __sdhci_finish_mrq(host, mrq);
>>>> @@ -3342,6 +3350,7 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 intmask)
>>>> if (intmask & SDHCI_INT_DATA_TIMEOUT) {
>>>> host->data_cmd = NULL;
>>>> data_cmd->error = -ETIMEDOUT;
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_CMD_TIMEOUT);
>>>> __sdhci_finish_mrq(host, data_cmd->mrq);
>>>> return;
>>>> }
>>>> @@ -3375,18 +3384,25 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 intmask)
>>>> return;
>>>> }
>>>>
>>>> - if (intmask & SDHCI_INT_DATA_TIMEOUT)
>>>> + if (intmask & SDHCI_INT_DATA_TIMEOUT) {
>>>> host->data->error = -ETIMEDOUT;
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_DAT_TIMEOUT);
>>>> + }
>>>> else if (intmask & SDHCI_INT_DATA_END_BIT)
>>>> host->data->error = -EILSEQ;
>>>> else if ((intmask & SDHCI_INT_DATA_CRC) &&
>>>> SDHCI_GET_CMD(sdhci_readw(host, SDHCI_COMMAND))
>>>> - != MMC_BUS_TEST_R)
>>>> + != MMC_BUS_TEST_R) {
>>>> host->data->error = -EILSEQ;
>>>> + if (host->cmd->opcode != MMC_SEND_TUNING_BLOCK ||
>>>> + host->cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200)
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_DAT_CRC);
>>>> + }
>>>> else if (intmask & SDHCI_INT_ADMA_ERROR) {
>>>> pr_err("%s: ADMA error: 0x%08x\n", mmc_hostname(host->mmc),
>>>> intmask);
>>>> sdhci_adma_show_error(host);
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_ADMA);
>>>> host->data->error = -EIO;
>>>> if (host->ops->adma_workaround)
>>>> host->ops->adma_workaround(host, intmask); @@ -3905,20 +3921,33
>>>> @@ bool sdhci_cqe_irq(struct sdhci_host *host, u32 intmask, int *cmd_error,
>>>> if (!host->cqe_on)
>>>> return false;
>>>>
>>>> - if (intmask & (SDHCI_INT_INDEX | SDHCI_INT_END_BIT | SDHCI_INT_CRC))
>>>> + if (intmask & (SDHCI_INT_INDEX | SDHCI_INT_END_BIT |
>>>> +SDHCI_INT_CRC)) {
>>>> *cmd_error = -EILSEQ;
>>>> - else if (intmask & SDHCI_INT_TIMEOUT)
>>>> + if (intmask & SDHCI_INT_CRC) {
>>>> + if (host->cmd->opcode != MMC_SEND_TUNING_BLOCK ||
>>>> + host->cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200)
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_CMD_CRC);
>>>> + }
>>>> + } else if (intmask & SDHCI_INT_TIMEOUT) {
>>>> *cmd_error = -ETIMEDOUT;
>>>> - else
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_CMD_TIMEOUT);
>>>> + } else
>>>> *cmd_error = 0;
>>>>
>>>> - if (intmask & (SDHCI_INT_DATA_END_BIT | SDHCI_INT_DATA_CRC))
>>>> + if (intmask & (SDHCI_INT_DATA_END_BIT | SDHCI_INT_DATA_CRC)) {
>>>> *data_error = -EILSEQ;
>>>> - else if (intmask & SDHCI_INT_DATA_TIMEOUT)
>>>> + if (intmask & SDHCI_INT_DATA_CRC) {
>>>> + if (host->cmd->opcode != MMC_SEND_TUNING_BLOCK ||
>>>> + host->cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200)
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_DAT_CRC);
>>>> + }
>>>> + } else if (intmask & SDHCI_INT_DATA_TIMEOUT) {
>>>> *data_error = -ETIMEDOUT;
>>>> - else if (intmask & SDHCI_INT_ADMA_ERROR)
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_DAT_TIMEOUT);
>>>> + } else if (intmask & SDHCI_INT_ADMA_ERROR) {
>>>> *data_error = -EIO;
>>>> - else
>>>> + mmc_debugfs_err_stats_inc(host->mmc, MMC_ERR_ADMA);
>>>> + } else
>>>> *data_error = 0;
>>>>
>>>> /* Clear selected interrupts. */
>>>> diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
>>>> index 7afb57c..c263f8f 100644
>>>> --- a/include/linux/mmc/host.h
>>>> +++ b/include/linux/mmc/host.h
>>>> @@ -93,6 +93,23 @@ struct mmc_clk_phase_map {
>>>>
>>>> struct mmc_host;
>>>>
>>>> +enum mmc_err_stat {
>>>> + MMC_ERR_CMD_TIMEOUT,
>>>> + MMC_ERR_CMD_CRC,
>>>> + MMC_ERR_DAT_TIMEOUT,
>>>> + MMC_ERR_DAT_CRC,
>>>> + MMC_ERR_AUTO_CMD,
>>>> + MMC_ERR_ADMA,
>>>> + MMC_ERR_TUNING,
>>>> + MMC_ERR_CMDQ_RED,
>>>> + MMC_ERR_CMDQ_GCE,
>>>> + MMC_ERR_CMDQ_ICCE,
>>>> + MMC_ERR_REQ_TIMEOUT,
>>>> + MMC_ERR_CMDQ_REQ_TIMEOUT,
>>>> + MMC_ERR_ICE_CFG,
>>>> + MMC_ERR_MAX,
>>>> +};
>>>> +
>>>> struct mmc_host_ops {
>>>> /*
>>>> * It is optional for the host to implement pre_req and post_req
>>>> in @@ -500,6 +517,8 @@ struct mmc_host {
>>>>
>>>> /* Host Software Queue support */
>>>> bool hsq_enabled;
>>>> + u32 err_stats[MMC_ERR_MAX];
>>>
>>> If you make it u64 then we don't have to think about the value overflowing.
>>>
>>>>>> Sure
>>>
>>>> + bool err_state;
>>>>
>>>> unsigned long private[] ____cacheline_aligned;
>>>> };
>>>> @@ -635,6 +654,24 @@ static inline enum dma_data_direction mmc_get_dma_dir(struct mmc_data *data)
>>>> return data->flags & MMC_DATA_WRITE ? DMA_TO_DEVICE :
>>>> DMA_FROM_DEVICE; }
>>>>
>>>> +static inline void mmc_debugfs_err_stats_enable(struct mmc_host
>>>> +*mmc) {
>>>> + mmc->err_state = true;
>>>> +}
>>>> +
>>>> +static inline void mmc_debugfs_err_stats_inc(struct mmc_host *mmc,
>>>> + enum mmc_err_stat stat) {
>>>> +
>>>> + /*
>>>> + * Ignore the command timeout errors observed during
>>>> + * the card init as those are excepted.
>>>> + */
>>>> + if (!mmc->err_state)
>>>> + mmc->err_stats[MMC_ERR_CMD_TIMEOUT] = 0;
>>>
>>> This would be better handled in the card init code somewhere, not here.
>>>
>>>>>>> Sure.
>>>
>>>> +
>>>> + mmc->err_stats[stat] += 1;
>>>> +}
>>>> +
>>>> int mmc_send_tuning(struct mmc_host *host, u32 opcode, int
>>>> *cmd_error); int mmc_send_abort_tuning(struct mmc_host *host, u32
>>>> opcode); int mmc_get_ext_csd(struct mmc_card *card, u8
>>>> **new_ext_csd);
>>>>
>>>
>>
>
