diff mbox series

[v4,07/10] drivers: qcom: rpmh-rsc: tcs_is_free() can just check tcs_in_use

Message ID 20200413100321.v4.7.Icf2213131ea652087f100129359052c83601f8b0@changeid (mailing list archive)
State New, archived
Headers show
Series drivers: qcom: rpmh-rsc: Cleanup / add lots of comments | expand

Commit Message

Doug Anderson April 13, 2020, 5:04 p.m. UTC 
tcs_is_free() had two checks in it: does the software think that the
TCS is free and does the hardware think that the TCS is free.  I
couldn't figure out in which case the hardware could think that a TCS
was in-use but software thought it was free.  Apparently there is no
case and the extra check can be removed.  This apparently has already
been done in a downstream patch.

Suggested-by: Maulik Shah <mkshah@codeaurora.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Maulik Shah <mkshah@codeaurora.org>
Tested-by: Maulik Shah <mkshah@codeaurora.org>
---

Changes in v4: None
Changes in v3:
- Replace ("...warn if state mismatch") w/ ("...just check tcs_in_use")

Changes in v2:
- Comment tcs_is_free() new for v2; replaces old patch 6.

 drivers/soc/qcom/rpmh-rsc.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

Comments

Stephen Boyd April 13, 2020, 9:58 p.m. UTC | #1 
Quoting Douglas Anderson (2020-04-13 10:04:12)
> tcs_is_free() had two checks in it: does the software think that the
> TCS is free and does the hardware think that the TCS is free.  I
> couldn't figure out in which case the hardware could think that a TCS
> was in-use but software thought it was free.  Apparently there is no
> case and the extra check can be removed.  This apparently has already
> been done in a downstream patch.
> 
> Suggested-by: Maulik Shah <mkshah@codeaurora.org>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> Reviewed-by: Maulik Shah <mkshah@codeaurora.org>
> Tested-by: Maulik Shah <mkshah@codeaurora.org>
> ---

Reviewed-by: Stephen Boyd <swboyd@chromium.org>
diff mbox series

Patch

diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c
index f0a7ada0c16f..4e76e5349c44 100644
--- a/drivers/soc/qcom/rpmh-rsc.c
+++ b/drivers/soc/qcom/rpmh-rsc.c
@@ -177,7 +177,6 @@  static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id,
  * @tcs_id: The global ID of this TCS.
  *
  * Returns true if nobody has claimed this TCS (by setting tcs_in_use).
- * If the TCS looks free, checks that the hardware agrees.
  *
  * Must be called with the drv->lock held or the tcs_lock for the TCS being
  * tested. If only the tcs_lock is held then it is possible that this
@@ -188,8 +187,7 @@  static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id,
  */
 static bool tcs_is_free(struct rsc_drv *drv, int tcs_id)
 {
-	return !test_bit(tcs_id, drv->tcs_in_use) &&
-	       read_tcs_reg(drv, RSC_DRV_STATUS, tcs_id);
+	return !test_bit(tcs_id, drv->tcs_in_use);
 }
 
 /**