On 29/08/2019 16:14, Philipp Zabel wrote:
Hi Tero,
On Wed, 2019-08-28 at 10:19 +0300, Tero Kristo wrote:
Poll for reset completion status during de-assertion of reset, otherwise
the IP in question might be accessed before it has left reset properly.
Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
---
drivers/soc/ti/omap_prm.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c
index fd5c431f8736..afeb70761b27 100644
--- a/drivers/soc/ti/omap_prm.c
+++ b/drivers/soc/ti/omap_prm.c
@@ -127,6 +127,7 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
u32 v;
int st_bit;
bool has_rstst;
+ int timeout = 0;
if (!_is_valid_reset(reset, id))
return -EINVAL;
@@ -153,6 +154,25 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
v &= ~(1 << id);
writel_relaxed(v, reset->prm->base + reset->prm->data->rstctrl);
+ if (!has_rstst)
+ return 0;
+
+ /* wait for the status to be set */
+ while (1) {
+ v = readl_relaxed(reset->prm->base + reset->prm->data->rstst);
+ v &= 1 << st_bit;
+ if (v)
+ break;
+ timeout++;
+ if (timeout > OMAP_RESET_MAX_WAIT) {
+ pr_err("%s: timedout waiting for %s:%lu\n", __func__,
+ dev_name(rcdev->dev), id);
+ return -EBUSY;
+ }
+
+ udelay(1);
+ }
This looks like you could use
readl_relaxed_poll_timeout(_atomic)
Yeah true, let me change that.
-Tero
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