From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Michael Turquette <mturquette@baylibre.com>,
Stephen Boyd <sboyd@kernel.org>,
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
Magnus Damm <magnus.damm@gmail.com>,
Joerg Roedel <joro@8bytes.org>,
Robin Murphy <robin.murphy@arm.com>,
Tomasz Figa <tomasz.figa@gmail.com>,
Sylwester Nawrocki <s.nawrocki@samsung.com>,
Will Deacon <will@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
Wolfram Sang <wsa+renesas@sang-engineering.com>,
Dejin Zheng <zhengdejin5@gmail.com>,
Kai-Heng Feng <kai.heng.feng@canonical.com>,
Nicholas Piggin <npiggin@gmail.com>,
Heiko Carstens <hca@linux.ibm.com>,
Peter Zijlstra <peterz@infradead.org>,
Russell King <linux@armlinux.org.uk>,
John Stultz <jstultz@google.com>,
Thomas Gleixner <tglx@linutronix.de>,
Tony Lindgren <tony@atomide.com>,
Krzysztof Kozlowski <krzk@kernel.org>,
Tero Kristo <tero.kristo@linux.intel.com>,
Ulf Hansson <ulf.hansson@linaro.org>,
"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
linux-renesas-soc@vger.kernel.org, linux-pm@vger.kernel.org,
iommu@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 6/7] soc: renesas: rmobile-sysc: Convert to readl_poll_timeout_atomic()
Date: Mon, 5 Jun 2023 15:15:16 +0200 [thread overview]
Message-ID: <CAMuHMdV9n3ypBG1HffvHxYke5Ym068ZK1s2QryE-rbVgFS9dzw@mail.gmail.com> (raw)
In-Reply-To: <ae4bf03ab8fd5a557c683086958d6764babc0723.1685692810.git.geert+renesas@glider.be>
On Fri, Jun 2, 2023 at 10:51 AM Geert Uytterhoeven
<geert+renesas@glider.be> wrote:
> Use readl_poll_timeout_atomic() instead of open-coding the same
> operation.
>
> 1. rmobile_pd_power_down(): as typically less than 20 retries are
> needed, PSTR_RETRIES (100) µs is a suitable timeout value.
>
> 2. __rmobile_pd_power_up(): the old method of first polling some
> cycles with a 1 µs delay, followed by more polling cycles without
> any delay didn't make much sense, as the latter was insignificant
> compared to the former. Furthermore, typically no retries are
> needed. Hence just retain the polling with delay.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> diff --git a/drivers/soc/renesas/rmobile-sysc.c b/drivers/soc/renesas/rmobile-sysc.c
> index 728ebac98e14a5cc..5d621c35fba1116a 100644
> @@ -74,25 +71,17 @@ static int rmobile_pd_power_down(struct generic_pm_domain *genpd)
>
> static int __rmobile_pd_power_up(struct rmobile_pm_domain *rmobile_pd)
> {
> - unsigned int mask = BIT(rmobile_pd->bit_shift);
> - unsigned int retry_count;
> - int ret = 0;
> + unsigned int val, mask = BIT(rmobile_pd->bit_shift);
> + int ret;
Oops, "ret" should still be initialized to zero.
>
> if (readl(rmobile_pd->base + PSTR) & mask)
> return ret;
>
> writel(mask, rmobile_pd->base + SWUCR);
>
> - for (retry_count = 2 * PSTR_RETRIES; retry_count; retry_count--) {
> - if (!(readl(rmobile_pd->base + SWUCR) & mask))
> - break;
> - if (retry_count > PSTR_RETRIES)
> - udelay(PSTR_DELAY_US);
> - else
> - cpu_relax();
> - }
> - if (!retry_count)
> - ret = -EIO;
> + ret = readl_poll_timeout_atomic(rmobile_pd->base + SWUCR, val,
> + (val & mask), PSTR_DELAY_US,
> + PSTR_RETRIES * PSTR_DELAY_US);
>
> pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n",
> rmobile_pd->genpd.name, mask,
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
next prev parent reply other threads:[~2023-06-05 13:15 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-02 8:50 [PATCH v3 0/7] iopoll: Busy loop and timeout improvements + conversions Geert Uytterhoeven
2023-06-02 8:50 ` [PATCH v3 1/7] iopoll: Call cpu_relax() in busy loops Geert Uytterhoeven
2023-06-02 8:50 ` [PATCH v3 2/7] iopoll: Do not use timekeeping in read_poll_timeout_atomic() Geert Uytterhoeven
2024-03-26 1:31 ` Zong Li
2024-04-18 9:20 ` Geert Uytterhoeven
2023-06-02 8:50 ` [PATCH v3 3/7] clk: renesas: cpg-mssr: Convert to readl_poll_timeout_atomic() Geert Uytterhoeven
2023-06-02 8:50 ` [PATCH v3 4/7] clk: renesas: mstp: " Geert Uytterhoeven
2023-06-02 8:50 ` [PATCH v3 5/7] clk: renesas: rzg2l: " Geert Uytterhoeven
2023-06-02 8:50 ` [PATCH v3 6/7] soc: renesas: rmobile-sysc: " Geert Uytterhoeven
2023-06-02 13:51 ` kernel test robot
2023-06-05 13:15 ` Geert Uytterhoeven [this message]
2023-06-02 8:50 ` [PATCH v3 7/7] iommu/ipmmu-vmsa: Convert to read_poll_timeout_atomic() Geert Uytterhoeven
2023-06-05 15:08 ` [PATCH v3 0/7] iopoll: Busy loop and timeout improvements + conversions Geert Uytterhoeven
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAMuHMdV9n3ypBG1HffvHxYke5Ym068ZK1s2QryE-rbVgFS9dzw@mail.gmail.com \
--to=geert@linux-m68k.org \
--cc=arnd@arndb.de \
--cc=geert+renesas@glider.be \
--cc=hca@linux.ibm.com \
--cc=iommu@lists.linux.dev \
--cc=joro@8bytes.org \
--cc=jstultz@google.com \
--cc=kai.heng.feng@canonical.com \
--cc=krzk@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=linux-renesas-soc@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=magnus.damm@gmail.com \
--cc=mturquette@baylibre.com \
--cc=npiggin@gmail.com \
--cc=peterz@infradead.org \
--cc=rafael.j.wysocki@intel.com \
--cc=robin.murphy@arm.com \
--cc=s.nawrocki@samsung.com \
--cc=sboyd@kernel.org \
--cc=tero.kristo@linux.intel.com \
--cc=tglx@linutronix.de \
--cc=tomasz.figa@gmail.com \
--cc=tony@atomide.com \
--cc=ulf.hansson@linaro.org \
--cc=vincent.guittot@linaro.org \
--cc=will@kernel.org \
--cc=wsa+renesas@sang-engineering.com \
--cc=yoshihiro.shimoda.uh@renesas.com \
--cc=zhengdejin5@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).