Re: [PATCH 4/5] coresight: Add better messages for coresight_timeout

[Suzuki K Poulose]

On 31/05/16 18:58, Joe Perches wrote:
> On Tue, 2016-05-31 at 12:57 +0100, Suzuki K Poulose wrote:
> > When we encounter a timeout waiting for a status change via
> > coresight_timeout, the caller always print the offset which
> > was tried. This is pretty much useless as it doesn't specify
> > the bit position we wait for. Also, one needs to lookup the
> > TRM to figure out, what was wrong. This patch changes all
> > such error messages to print something more meaningful.
>
> trivia:
>
> Perhaps consistently using
> 	dev_err(dev, "timeout while waiting for %s\n", "<foo>");
> could make the object code a bit smaller.
>
> > diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
> []
> > @@ -184,8 +184,7 @@ static void etb_disable_hw(struct etb_drvdata *drvdata)
> >
> >   	if (coresight_timeout(drvdata->base, ETB_FFCR, ETB_FFCR_BIT, 0)) {
> >   		dev_err(drvdata->dev,
> > -			"timeout observed when probing at offset %#x\n",
> > -			ETB_FFCR);
> > +			"timeout while waiting for completion of Manual Flush\n");
>
> ie:
> 		dev_err(drvdata->dev,
> 			"timeout while waiting for %s\n",
> 			"completion of Manual Flush");
>
> but that depends on how many of these coresight
> files are compiled and linked.

Or we could move the timeout message to coresight_timeout(). The only disadvantage is
if a caller is OK with silent timeouts. How about :

int coresight_timeout(void *base, u32 offset, u32 bit, u32 val, char *info)

where the message can be suppressed if info == NULL ?

Mathieu, your thoughts ?

> There is a while/when usage difference in some of
> the output messages.

Right, I will fix them. This was a merged version of individual patches, hence
the changes.

Cheers
Suzuki