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

On 1 June 2016 at 03:34, Suzuki K Poulose [off-list ref] wrote:

On 31/05/16 18:58, Joe Perches wrote:

quoted

On Tue, 2016-05-31 at 12:57 +0100, Suzuki K Poulose wrote:

quoted

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.

quoted

diff --git a/drivers/hwtracing/coresight/coresight-etb10.c

b/drivers/hwtracing/coresight/coresight-etb10.c

[]

quoted

@@ -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 ?

I'd rather keep things separate.

Thanks,
Mathieu

quoted

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