From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sowjanya Komatineni Subject: Re: [PATCH v9 20/22] soc/tegra: pmc: Configure deep sleep control settings Date: Mon, 19 Aug 2019 11:20:21 -0700 Message-ID: <2092e557-06cb-4a74-fe40-1d83bf67ccca@nvidia.com> References: <1565984527-5272-1-git-send-email-skomatineni@nvidia.com> <1565984527-5272-21-git-send-email-skomatineni@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Dmitry Osipenko , thierry.reding@gmail.com, jonathanh@nvidia.com, tglx@linutronix.de, jason@lakedaemon.net, marc.zyngier@arm.com, linus.walleij@linaro.org, stefan@agner.ch, mark.rutland@arm.com Cc: pdeschrijver@nvidia.com, pgaikwad@nvidia.com, sboyd@kernel.org, linux-clk@vger.kernel.org, linux-gpio@vger.kernel.org, jckuo@nvidia.com, josephl@nvidia.com, talho@nvidia.com, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, mperttunen@nvidia.com, spatra@nvidia.com, robh+dt@kernel.org, devicetree@vger.kernel.org, rjw@rjwysocki.net, viresh.kumar@linaro.org, linux-pm@vger.kernel.org List-Id: devicetree@vger.kernel.org On 8/19/19 9:48 AM, Dmitry Osipenko wrote: > 16.08.2019 22:42, Sowjanya Komatineni =D0=BF=D0=B8=D1=88=D0=B5=D1=82: >> Tegra210 and prior Tegra chips have deep sleep entry and wakeup related >> timings which are platform specific that should be configured before >> entering into deep sleep. >> >> Below are the timing specific configurations for deep sleep entry and >> wakeup. >> - Core rail power-on stabilization timer >> - OSC clock stabilization timer after SOC rail power is stabilized. >> - Core power off time is the minimum wake delay to keep the system >> in deep sleep state irrespective of any quick wake event. >> >> These values depends on the discharge time of regulators and turn OFF >> time of the PMIC to allow the complete system to finish entering into >> deep sleep state. >> >> These values vary based on the platform design and are specified >> through the device tree. >> >> This patch has implementation to configure these timings which are must >> to have for proper deep sleep and wakeup operations. >> >> Signed-off-by: Sowjanya Komatineni >> --- >> drivers/soc/tegra/pmc.c | 14 +++++++++++++- >> 1 file changed, 13 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c >> index 53ed70773872..710969043668 100644 >> --- a/drivers/soc/tegra/pmc.c >> +++ b/drivers/soc/tegra/pmc.c >> @@ -88,6 +88,8 @@ >> =20 >> #define PMC_CPUPWRGOOD_TIMER 0xc8 >> #define PMC_CPUPWROFF_TIMER 0xcc >> +#define PMC_COREPWRGOOD_TIMER 0x3c >> +#define PMC_COREPWROFF_TIMER 0xe0 >> =20 >> #define PMC_PWR_DET_VALUE 0xe4 >> =20 >> @@ -2277,7 +2279,7 @@ static const struct tegra_pmc_regs tegra20_pmc_reg= s =3D { >> =20 >> static void tegra20_pmc_init(struct tegra_pmc *pmc) >> { >> - u32 value; >> + u32 value, osc, pmu, off; >> =20 >> /* Always enable CPU power request */ >> value =3D tegra_pmc_readl(pmc, PMC_CNTRL); >> @@ -2303,6 +2305,16 @@ static void tegra20_pmc_init(struct tegra_pmc *pm= c) >> value =3D tegra_pmc_readl(pmc, PMC_CNTRL); >> value |=3D PMC_CNTRL_SYSCLK_OE; >> tegra_pmc_writel(pmc, value, PMC_CNTRL); >> + >> + /* program core timings which are applicable only for suspend state */ >> + if (pmc->suspend_mode !=3D TEGRA_SUSPEND_NONE) { >> + osc =3D DIV_ROUND_UP(pmc->core_osc_time * 8192, 1000000); >> + pmu =3D DIV_ROUND_UP(pmc->core_pmu_time * 32768, 1000000); >> + off =3D DIV_ROUND_UP(pmc->core_off_time * 32768, 1000000); >> + tegra_pmc_writel(pmc, ((osc << 8) & 0xff00) | (pmu & 0xff), >> + PMC_COREPWRGOOD_TIMER); >> + tegra_pmc_writel(pmc, off, PMC_COREPWROFF_TIMER); >> + } >> } >> =20 >> static void tegra20_pmc_setup_irq_polarity(struct tegra_pmc *pmc, >> > In the previous version of this patch there were checks for zero values > of the timers with intention to skip programming of the timers if value > is zero. I'm a bit puzzled by the new version, given that SUSPEND_NONE > means that suspending isn't available at all and thus PMC timers won't > be utilized, hence it shouldn't matter what values are programmed for > the counters, isn't it? Yes, as I see in documentation we already specify all these timings are=20 required properties when suspend mode is used, I updated in this version=20 to program core timings only when suspend mode is enabled.