From: Simon Horman <horms@verge.net.au> To: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Linux-Renesas <linux-renesas-soc@vger.kernel.org>, linux-arm-kernel@lists.infradead.org, Magnus Damm <magnus.damm@gmail.com>, Takeshi Kihara <takeshi.kihara.df@renesas.com> Subject: Re: [PATCH v4 2/6] clk: renesas: rcar-gen3: Add Z2 clock divider support Date: Mon, 29 Jan 2018 16:19:29 +0100 [thread overview] Message-ID: <20180129151928.ooh5uirmjgtyjcjm@verge.net.au> (raw) In-Reply-To: <CAMuHMdU734+i3n5fa1jZfzY+kanH5k07YRLJq_b_UprOh=hSNw@mail.gmail.com> On Mon, Jan 29, 2018 at 04:01:49PM +0100, Geert Uytterhoeven wrote: > Hi Simon, > > On Mon, Jan 29, 2018 at 3:24 PM, Simon Horman <horms@verge.net.au> wrote: > > On Fri, Jan 05, 2018 at 03:35:13PM +0100, Geert Uytterhoeven wrote: > >> On Fri, Jan 5, 2018 at 3:04 PM, Simon Horman <horms@verge.net.au> wrote: > >> > On Wed, Jan 03, 2018 at 01:47:08PM +0100, Geert Uytterhoeven wrote: > >> >> On Wed, Jan 3, 2018 at 1:18 PM, Simon Horman <horms+renesas@verge.net.au> wrote: > >> >> > From: Takeshi Kihara <takeshi.kihara.df@renesas.com> > >> >> > This patch adds Z2 clock divider support for R-Car Gen3 SoC. > >> >> > > >> >> > Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com> > >> >> > Signed-off-by: Simon Horman <horms+renesas@verge.net.au> > >> > >> >> As the CPG/MSSR driver now has suspend/resume support, do we need > >> >> a notifier to restore the Z or Z2 registers? Or is that handled automatically > >> >> by cpufreq during system resume, for both the primary and the secondary > >> >> CPU cores? > >> > > >> > I am a bit unsure. > >> > > >> > When using the A57 cores, which is the default case, the Z clk is queried > >> > by CPUFreq on resume. It appears that on my system its already set to the > >> > correct value but I assume if it was not then it would be reset. However, > >> > this does not cover Z2 clk. So perhaps to be safe we need to register > >> > notifiers and make sure they they play nicely with CPUFreq? > >> > >> Of course the CPU is special: unlike many other devices, it must be running > >> when the kernel is reentered upon system resume. > >> It may be running using a different frequency setting, though. > >> However, following "opp-suspend", the system will always suspend with the > >> Z clock running at 1.5GHz, which is the default? > >> So Z is probably OK. > >> > >> It's more interesting to check what happens when the little cores are > >> enabled as well (unfortunately that requires different firmware). > >> 1. Does cpufreq handle them correctly when they are onlined again during > >> system resume? > > > > I tested this by updating the firmware on an H3 ES2.0 / Salvator-XS > > using the instructions at > > https://elinux.org/R-Car/Virtualization#Enabling_HYP_Support > > > # grep -E -w "pll[01]|z|z2" /sys/kernel/debug/clk/clk_summary > > z2 0 0 1198080000 0 0 > > .pll1 1 1 3194880000 0 0 > > .pll0 0 0 2995200000 0 0 > > z 0 0 1497600000 0 0 > > You know it's PLL2, not PLL1, you want to look at? ;-) Sorry, I will double check but I had looked at PLL2 earlier: I just messed things up when preparing things to post in email. > Thanks for checking, looks all good! Ok, so do you think we can merge this series with the off-by-one problem fixed?
WARNING: multiple messages have this Message-ID (diff)
From: horms@verge.net.au (Simon Horman) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 2/6] clk: renesas: rcar-gen3: Add Z2 clock divider support Date: Mon, 29 Jan 2018 16:19:29 +0100 [thread overview] Message-ID: <20180129151928.ooh5uirmjgtyjcjm@verge.net.au> (raw) In-Reply-To: <CAMuHMdU734+i3n5fa1jZfzY+kanH5k07YRLJq_b_UprOh=hSNw@mail.gmail.com> On Mon, Jan 29, 2018 at 04:01:49PM +0100, Geert Uytterhoeven wrote: > Hi Simon, > > On Mon, Jan 29, 2018 at 3:24 PM, Simon Horman <horms@verge.net.au> wrote: > > On Fri, Jan 05, 2018 at 03:35:13PM +0100, Geert Uytterhoeven wrote: > >> On Fri, Jan 5, 2018 at 3:04 PM, Simon Horman <horms@verge.net.au> wrote: > >> > On Wed, Jan 03, 2018 at 01:47:08PM +0100, Geert Uytterhoeven wrote: > >> >> On Wed, Jan 3, 2018 at 1:18 PM, Simon Horman <horms+renesas@verge.net.au> wrote: > >> >> > From: Takeshi Kihara <takeshi.kihara.df@renesas.com> > >> >> > This patch adds Z2 clock divider support for R-Car Gen3 SoC. > >> >> > > >> >> > Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com> > >> >> > Signed-off-by: Simon Horman <horms+renesas@verge.net.au> > >> > >> >> As the CPG/MSSR driver now has suspend/resume support, do we need > >> >> a notifier to restore the Z or Z2 registers? Or is that handled automatically > >> >> by cpufreq during system resume, for both the primary and the secondary > >> >> CPU cores? > >> > > >> > I am a bit unsure. > >> > > >> > When using the A57 cores, which is the default case, the Z clk is queried > >> > by CPUFreq on resume. It appears that on my system its already set to the > >> > correct value but I assume if it was not then it would be reset. However, > >> > this does not cover Z2 clk. So perhaps to be safe we need to register > >> > notifiers and make sure they they play nicely with CPUFreq? > >> > >> Of course the CPU is special: unlike many other devices, it must be running > >> when the kernel is reentered upon system resume. > >> It may be running using a different frequency setting, though. > >> However, following "opp-suspend", the system will always suspend with the > >> Z clock running at 1.5GHz, which is the default? > >> So Z is probably OK. > >> > >> It's more interesting to check what happens when the little cores are > >> enabled as well (unfortunately that requires different firmware). > >> 1. Does cpufreq handle them correctly when they are onlined again during > >> system resume? > > > > I tested this by updating the firmware on an H3 ES2.0 / Salvator-XS > > using the instructions at > > https://elinux.org/R-Car/Virtualization#Enabling_HYP_Support > > > # grep -E -w "pll[01]|z|z2" /sys/kernel/debug/clk/clk_summary > > z2 0 0 1198080000 0 0 > > .pll1 1 1 3194880000 0 0 > > .pll0 0 0 2995200000 0 0 > > z 0 0 1497600000 0 0 > > You know it's PLL2, not PLL1, you want to look at? ;-) Sorry, I will double check but I had looked at PLL2 earlier: I just messed things up when preparing things to post in email. > Thanks for checking, looks all good! Ok, so do you think we can merge this series with the off-by-one problem fixed?
next prev parent reply other threads:[~2018-01-29 15:19 UTC|newest] Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-01-03 12:18 [PATCH v4 0/6] clk: renesas: r8a779[56]: Add Z and Z2 clock support Simon Horman 2018-01-03 12:18 ` Simon Horman 2018-01-03 12:18 ` [PATCH v4 1/6] clk: renesas: rcar-gen3: Add Z clock divider support Simon Horman 2018-01-03 12:18 ` Simon Horman 2018-01-03 12:18 ` [PATCH v4 2/6] clk: renesas: rcar-gen3: Add Z2 " Simon Horman 2018-01-03 12:18 ` Simon Horman 2018-01-03 12:47 ` Geert Uytterhoeven 2018-01-03 12:47 ` Geert Uytterhoeven 2018-01-05 14:04 ` Simon Horman 2018-01-05 14:04 ` Simon Horman 2018-01-05 14:35 ` Geert Uytterhoeven 2018-01-05 14:35 ` Geert Uytterhoeven 2018-01-08 8:02 ` Simon Horman 2018-01-08 8:02 ` Simon Horman 2018-01-08 8:06 ` Geert Uytterhoeven 2018-01-08 8:06 ` Geert Uytterhoeven 2018-01-29 14:24 ` Simon Horman 2018-01-29 14:24 ` Simon Horman 2018-01-29 15:01 ` Geert Uytterhoeven 2018-01-29 15:01 ` Geert Uytterhoeven 2018-01-29 15:19 ` Simon Horman [this message] 2018-01-29 15:19 ` Simon Horman 2018-01-29 15:46 ` Geert Uytterhoeven 2018-01-29 15:46 ` Geert Uytterhoeven 2018-01-29 16:42 ` Simon Horman 2018-01-29 16:42 ` Simon Horman 2018-01-29 15:51 ` Simon Horman 2018-01-29 15:51 ` Simon Horman 2018-01-29 16:31 ` Simon Horman 2018-01-29 16:31 ` Simon Horman 2018-01-03 12:18 ` [PATCH v4 3/6] clk: renesas: r8a7795: Add Z clock Simon Horman 2018-01-03 12:18 ` Simon Horman 2018-01-03 12:18 ` [PATCH v4 4/6] clk: renesas: r8a7795: Add Z2 clock Simon Horman 2018-01-03 12:18 ` Simon Horman 2018-01-03 12:18 ` [PATCH v4 5/6] clk: renesas: r8a7796: Add Z clock Simon Horman 2018-01-03 12:18 ` Simon Horman 2018-01-03 12:18 ` [PATCH v4 6/6] clk: renesas: r8a7796: Add Z2 clock Simon Horman 2018-01-03 12:18 ` Simon Horman
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=20180129151928.ooh5uirmjgtyjcjm@verge.net.au \ --to=horms@verge.net.au \ --cc=geert@linux-m68k.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-renesas-soc@vger.kernel.org \ --cc=magnus.damm@gmail.com \ --cc=takeshi.kihara.df@renesas.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: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.