From mboxrd@z Thu Jan 1 00:00:00 1970
From: Philipp Zabel
Subject: Re: [PATCHv7 3/9] soc: ti: omap-prm: poll for reset complete during
de-assert
Date: Tue, 08 Oct 2019 13:40:08 +0200
Message-ID: <1570534808.18914.2.camel@pengutronix.de>
References: <20191008071913.28740-1-t-kristo@ti.com>
<20191008071913.28740-4-t-kristo@ti.com>
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To: Tero Kristo , linux-omap@vger.kernel.org, ssantosh@kernel.org
Cc: tony@atomide.com, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org
List-Id: devicetree@vger.kernel.org
On Tue, 2019-10-08 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
> ---
> drivers/soc/ti/omap_prm.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c
> index ab0b66ad715d..96fa2aad9b93 100644
> --- a/drivers/soc/ti/omap_prm.c
> +++ b/drivers/soc/ti/omap_prm.c
> @@ -153,6 +153,18 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
> writel_relaxed(v, reset->prm->base + reset->prm->data->rstctrl);
> spin_unlock_irqrestore(&reset->lock, flags);
>
> + if (!has_rstst)
> + return 0;
> +
> + /* wait for the status to be set */
> + ret = readl_relaxed_poll_timeout(reset->prm->base +
> + reset->prm->data->rstst,
> + v, v & BIT(st_bit), 1,
> + OMAP_RESET_MAX_WAIT);
> + if (ret)
> + pr_err("%s: timedout waiting for %s:%lu\n", __func__,
> + reset->prm->data->name, id);
> +
> return 0;
> }
>
Reviewed-by: Philipp Zabel
regards
Philipp