From: Jeeja KP <jeeja.kp@xxxxxxxxx>
Poll implementation is not quite accurate, especially for smaller
values of timeout or timeout values close to the actual timeout needed
Use jiffies to set the timeout value and time_before() to get the
accurate time. So update the dsp register poll implementation to
provide accurate timeout using jiffies.
Signed-off-by: Jayachandran B <jayachandran.b@xxxxxxxxx>
Signed-off-by: Jeeja KP <jeeja.kp@xxxxxxxxx>
---
sound/soc/intel/common/sst-dsp.c | 52 ++++++++++++++++++++--------------------
1 file changed, 26 insertions(+), 26 deletions(-)
diff --git a/sound/soc/intel/common/sst-dsp.c b/sound/soc/intel/common/sst-dsp.c
index c00ede4..11c0805 100644
--- a/sound/soc/intel/common/sst-dsp.c
+++ b/sound/soc/intel/common/sst-dsp.c
@@ -252,44 +252,44 @@ void sst_dsp_shim_update_bits_forced(struct sst_dsp *sst, u32 offset,
EXPORT_SYMBOL_GPL(sst_dsp_shim_update_bits_forced);
int sst_dsp_register_poll(struct sst_dsp *ctx, u32 offset, u32 mask,
- u32 target, u32 timeout, char *operation)
+ u32 target, u32 time, char *operation)
{
- int time, ret;
u32 reg;
- bool done = false;
+ unsigned long timeout;
+ int k = 0, s = 500;
/*
- * we will poll for couple of ms using mdelay, if not successful
- * then go to longer sleep using usleep_range
+ * split the loop into sleeps of varying resolution. more accurately,
+ * the range of wakeups are:
+ * Phase 1(first 5ms): min sleep 0.5ms; max sleep 1ms.
+ * Phase 2:( 5ms to 10ms) : min sleep 0.5ms; max sleep 10ms
+ * (usleep_range (500, 1000) and usleep_range(5000, 10000) are
+ * both possible in this phase depending on whether k > 10 or not).
+ * Phase 3: (beyond 10 ms) min sleep 5ms; max sleep 10ms.
*/
- /* check if set state successful */
- for (time = 0; time < 5; time++) {
- if ((sst_dsp_shim_read_unlocked(ctx, offset) & mask) == target) {
- done = true;
- break;
- }
- mdelay(1);
+ timeout = jiffies + msecs_to_jiffies(time);
+ while (((sst_dsp_shim_read_unlocked(ctx, offset) & mask) != target)
+ && time_before(jiffies, timeout)) {
+ k++;
+ if (k > 10)
+ s = 5000;
+
+ usleep_range(s, 2*s);
}
- if (done == false) {
- /* sleeping in 10ms steps so adjust timeout value */
- timeout /= 10;
+ reg = sst_dsp_shim_read_unlocked(ctx, offset);
- for (time = 0; time < timeout; time++) {
- if ((sst_dsp_shim_read_unlocked(ctx, offset) & mask) == target)
- break;
+ if ((reg & mask) == target) {
+ dev_dbg(ctx->dev, "FW Poll Status: reg=%#x %s successful\n",
+ reg, operation);
- usleep_range(5000, 10000);
- }
+ return 0;
}
- reg = sst_dsp_shim_read_unlocked(ctx, offset);
- dev_dbg(ctx->dev, "FW Poll Status: reg=%#x %s %s\n", reg, operation,
- (time < timeout) ? "successful" : "timedout");
- ret = time < timeout ? 0 : -ETIME;
-
- return ret;
+ dev_dbg(ctx->dev, "FW Poll Status: reg=%#x %s timedout\n",
+ reg, operation);
+ return -ETIME;
}
EXPORT_SYMBOL_GPL(sst_dsp_register_poll);
--
2.5.0
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