diff mbox series

[v13,3/5] soc: qcom: rpmh: Invalidate SLEEP and WAKE TCSes before flushing new data

Message ID 1583746236-13325-4-git-send-email-mkshah@codeaurora.org
State New
Headers show
Series [v13,1/5] arm64: dts: qcom: sc7180: Add cpuidle low power states | expand

Commit Message

Maulik Shah March 9, 2020, 9:30 a.m. UTC
TCSes have previously programmed data when rpmh_flush is called.
This can cause old data to trigger along with newly flushed.

Fix this by cleaning SLEEP and WAKE TCSes before new data is flushed.

With this there is no need to invoke rpmh_rsc_invalidate() call from
rpmh_invalidate().

Simplify rpmh_invalidate() by moving invalidate_batch() inside.

Fixes: 600513dfeef3 ("drivers: qcom: rpmh: cache sleep/wake state requests")
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
---
 drivers/soc/qcom/rpmh.c | 36 +++++++++++++++---------------------
 1 file changed, 15 insertions(+), 21 deletions(-)

Comments

Doug Anderson March 9, 2020, 11:42 p.m. UTC | #1
Hi,

On Mon, Mar 9, 2020 at 2:31 AM Maulik Shah <mkshah@codeaurora.org> wrote:
>
> TCSes have previously programmed data when rpmh_flush is called.
> This can cause old data to trigger along with newly flushed.
>
> Fix this by cleaning SLEEP and WAKE TCSes before new data is flushed.
>
> With this there is no need to invoke rpmh_rsc_invalidate() call from
> rpmh_invalidate().
>
> Simplify rpmh_invalidate() by moving invalidate_batch() inside.
>
> Fixes: 600513dfeef3 ("drivers: qcom: rpmh: cache sleep/wake state requests")
> Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
> ---
>  drivers/soc/qcom/rpmh.c | 36 +++++++++++++++---------------------
>  1 file changed, 15 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
> index 03630ae..5bed8f4 100644
> --- a/drivers/soc/qcom/rpmh.c
> +++ b/drivers/soc/qcom/rpmh.c
> @@ -317,19 +317,6 @@ static int flush_batch(struct rpmh_ctrlr *ctrlr)
>         return ret;
>  }
>
> -static void invalidate_batch(struct rpmh_ctrlr *ctrlr)
> -{
> -       struct batch_cache_req *req, *tmp;
> -       unsigned long flags;
> -
> -       spin_lock_irqsave(&ctrlr->cache_lock, flags);
> -       list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list)
> -               kfree(req);
> -       INIT_LIST_HEAD(&ctrlr->batch_cache);
> -       ctrlr->dirty = true;
> -       spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
> -}
> -
>  /**
>   * rpmh_write_batch: Write multiple sets of RPMH commands and wait for the
>   * batch to finish.
> @@ -467,6 +454,11 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr)
>                 return 0;
>         }
>
> +       /* Invalidate the TCSes first to avoid stale data */
> +       do {
> +               ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr));
> +       } while (ret == -EAGAIN);
> +

You forgot to actually check the return value.

if (ret)
  return ret;


>         /* First flush the cached batch requests */
>         ret = flush_batch(ctrlr);
>         if (ret)
> @@ -503,19 +495,21 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr)
>   *
>   * @dev: The device making the request
>   *
> - * Invalidate the sleep and active values in the TCS blocks.
> + * Invalidate the sleep and wake values in batch_cache.

Thanks for updating this.  It was on my todo list.  Can you also
update the function description, which still says "Invalidate all
sleep and active sets sets."  While you're at it, remove the double
"sets".
Maulik Shah March 10, 2020, 11:09 a.m. UTC | #2
On 3/10/2020 5:12 AM, Doug Anderson wrote:
> Hi,
>
> On Mon, Mar 9, 2020 at 2:31 AM Maulik Shah <mkshah@codeaurora.org> wrote:
>> TCSes have previously programmed data when rpmh_flush is called.
>> This can cause old data to trigger along with newly flushed.
>>
>> Fix this by cleaning SLEEP and WAKE TCSes before new data is flushed.
>>
>> With this there is no need to invoke rpmh_rsc_invalidate() call from
>> rpmh_invalidate().
>>
>> Simplify rpmh_invalidate() by moving invalidate_batch() inside.
>>
>> Fixes: 600513dfeef3 ("drivers: qcom: rpmh: cache sleep/wake state requests")
>> Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
>> ---
>>  drivers/soc/qcom/rpmh.c | 36 +++++++++++++++---------------------
>>  1 file changed, 15 insertions(+), 21 deletions(-)
>>
>> diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
>> index 03630ae..5bed8f4 100644
>> --- a/drivers/soc/qcom/rpmh.c
>> +++ b/drivers/soc/qcom/rpmh.c
>> @@ -317,19 +317,6 @@ static int flush_batch(struct rpmh_ctrlr *ctrlr)
>>         return ret;
>>  }
>>
>> -static void invalidate_batch(struct rpmh_ctrlr *ctrlr)
>> -{
>> -       struct batch_cache_req *req, *tmp;
>> -       unsigned long flags;
>> -
>> -       spin_lock_irqsave(&ctrlr->cache_lock, flags);
>> -       list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list)
>> -               kfree(req);
>> -       INIT_LIST_HEAD(&ctrlr->batch_cache);
>> -       ctrlr->dirty = true;
>> -       spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
>> -}
>> -
>>  /**
>>   * rpmh_write_batch: Write multiple sets of RPMH commands and wait for the
>>   * batch to finish.
>> @@ -467,6 +454,11 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr)
>>                 return 0;
>>         }
>>
>> +       /* Invalidate the TCSes first to avoid stale data */
>> +       do {
>> +               ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr));
>> +       } while (ret == -EAGAIN);
>> +
> You forgot to actually check the return value.
>
> if (ret)
>   return ret;
Done.
>
>>         /* First flush the cached batch requests */
>>         ret = flush_batch(ctrlr);
>>         if (ret)
>> @@ -503,19 +495,21 @@ int rpmh_flush(struct rpmh_ctrlr *ctrlr)
>>   *
>>   * @dev: The device making the request
>>   *
>> - * Invalidate the sleep and active values in the TCS blocks.
>> + * Invalidate the sleep and wake values in batch_cache.
> Thanks for updating this.  It was on my todo list.  Can you also
> update the function description, which still says "Invalidate all
> sleep and active sets sets."  While you're at it, remove the double
> "sets".

Done.

Thanks,
Maulik
diff mbox series

Patch

diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
index 03630ae..5bed8f4 100644
--- a/drivers/soc/qcom/rpmh.c
+++ b/drivers/soc/qcom/rpmh.c
@@ -317,19 +317,6 @@  static int flush_batch(struct rpmh_ctrlr *ctrlr)
 	return ret;
 }
 
-static void invalidate_batch(struct rpmh_ctrlr *ctrlr)
-{
-	struct batch_cache_req *req, *tmp;
-	unsigned long flags;
-
-	spin_lock_irqsave(&ctrlr->cache_lock, flags);
-	list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list)
-		kfree(req);
-	INIT_LIST_HEAD(&ctrlr->batch_cache);
-	ctrlr->dirty = true;
-	spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
-}
-
 /**
  * rpmh_write_batch: Write multiple sets of RPMH commands and wait for the
  * batch to finish.
@@ -467,6 +454,11 @@  int rpmh_flush(struct rpmh_ctrlr *ctrlr)
 		return 0;
 	}
 
+	/* Invalidate the TCSes first to avoid stale data */
+	do {
+		ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr));
+	} while (ret == -EAGAIN);
+
 	/* First flush the cached batch requests */
 	ret = flush_batch(ctrlr);
 	if (ret)
@@ -503,19 +495,21 @@  int rpmh_flush(struct rpmh_ctrlr *ctrlr)
  *
  * @dev: The device making the request
  *
- * Invalidate the sleep and active values in the TCS blocks.
+ * Invalidate the sleep and wake values in batch_cache.
  */
 int rpmh_invalidate(const struct device *dev)
 {
 	struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev);
-	int ret;
-
-	invalidate_batch(ctrlr);
+	struct batch_cache_req *req, *tmp;
+	unsigned long flags;
 
-	do {
-		ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr));
-	} while (ret == -EAGAIN);
+	spin_lock_irqsave(&ctrlr->cache_lock, flags);
+	list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list)
+		kfree(req);
+	INIT_LIST_HEAD(&ctrlr->batch_cache);
+	ctrlr->dirty = true;
+	spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
 
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL(rpmh_invalidate);