From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sowjanya Komatineni Subject: Re: [PATCH V2 02/12] pinctrl: tegra: add suspend and resume support Date: Wed, 29 May 2019 13:11:08 -0700 Message-ID: <0f087659-cdde-9f89-55a2-d399ee539431@nvidia.com> References: <1559084936-4610-1-git-send-email-skomatineni@nvidia.com> <1559084936-4610-3-git-send-email-skomatineni@nvidia.com> <6273a790-d4b7-c501-3fec-d9816288b139@gmail.com> <11fe4d9a-6d8e-bc4f-b764-a849571fb6b0@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <11fe4d9a-6d8e-bc4f-b764-a849571fb6b0@gmail.com> 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 List-Id: devicetree@vger.kernel.org On 5/29/19 12:32 PM, Dmitry Osipenko wrote: > 29.05.2019 21:14, Sowjanya Komatineni =D0=BF=D0=B8=D1=88=D0=B5=D1=82: >> On 5/29/19 8:29 AM, Dmitry Osipenko wrote: >>> 29.05.2019 2:08, Sowjanya Komatineni =D0=BF=D0=B8=D1=88=D0=B5=D1=82: >>>> This patch adds suspend and resume support for Tegra pinctrl driver >>>> and registers them to syscore so the pinmux settings are restored >>>> before the devices resume. >>>> >>>> Signed-off-by: Sowjanya Komatineni >>>> --- >>>> =C2=A0 drivers/pinctrl/tegra/pinctrl-tegra.c=C2=A0=C2=A0=C2=A0 | 68 >>>> +++++++++++++++++++++++++++++++- >>>> =C2=A0 drivers/pinctrl/tegra/pinctrl-tegra.h=C2=A0=C2=A0=C2=A0 |=C2= =A0 3 ++ >>>> =C2=A0 drivers/pinctrl/tegra/pinctrl-tegra114.c |=C2=A0 1 + >>>> =C2=A0 drivers/pinctrl/tegra/pinctrl-tegra124.c |=C2=A0 1 + >>>> =C2=A0 drivers/pinctrl/tegra/pinctrl-tegra20.c=C2=A0 |=C2=A0 1 + >>>> =C2=A0 drivers/pinctrl/tegra/pinctrl-tegra210.c |=C2=A0 1 + >>>> =C2=A0 drivers/pinctrl/tegra/pinctrl-tegra30.c=C2=A0 |=C2=A0 1 + >>>> =C2=A0 7 files changed, 75 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/pinctrl/tegra/pinctrl-tegra.c >>>> b/drivers/pinctrl/tegra/pinctrl-tegra.c >>>> index a5008c066bac..bdc47e62c457 100644 >>>> --- a/drivers/pinctrl/tegra/pinctrl-tegra.c >>>> +++ b/drivers/pinctrl/tegra/pinctrl-tegra.c >>>> @@ -28,11 +28,18 @@ >>>> =C2=A0 #include >>>> =C2=A0 #include >>>> =C2=A0 #include >>>> +#include >>>> =C2=A0 =C2=A0 #include "../core.h" >>>> =C2=A0 #include "../pinctrl-utils.h" >>>> =C2=A0 #include "pinctrl-tegra.h" >>>> =C2=A0 +#define EMMC2_PAD_CFGPADCTRL_0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0x1c8 >>>> +#define EMMC4_PAD_CFGPADCTRL_0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0 0x1e0 >>>> +#define EMMC_DPD_PARKING=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0 (0x1fff << 14) >>>> + >>>> +static struct tegra_pmx *pmx; >>>> + >>>> =C2=A0 static inline u32 pmx_readl(struct tegra_pmx *pmx, u32 bank, u= 32 reg) >>>> =C2=A0 { >>>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 return readl(pmx->regs[bank] + reg); >>>> @@ -629,6 +636,50 @@ static void >>>> tegra_pinctrl_clear_parked_bits(struct tegra_pmx *pmx) >>>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 } >>>> =C2=A0 } >>>> =C2=A0 +static int __maybe_unused tegra_pinctrl_suspend(void) >>>> +{ >>>> +=C2=A0=C2=A0=C2=A0 u32 *backup_regs =3D pmx->backup_regs; >>>> +=C2=A0=C2=A0=C2=A0 u32 *regs; >>>> +=C2=A0=C2=A0=C2=A0 int i, j; >>>> + >>>> +=C2=A0=C2=A0=C2=A0 for (i =3D 0; i < pmx->nbanks; i++) { >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 regs =3D pmx->regs[i]; >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 for (j =3D 0; j < pmx->reg= _bank_size[i] / 4; j++) >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 *b= ackup_regs++ =3D readl(regs++); >>>> +=C2=A0=C2=A0=C2=A0 } >>>> + >>>> +=C2=A0=C2=A0=C2=A0 return pinctrl_force_sleep(pmx->pctl); >>>> +} >>>> + >>>> +static void __maybe_unused tegra_pinctrl_resume(void) >>>> +{ >>>> +=C2=A0=C2=A0=C2=A0 u32 *backup_regs =3D pmx->backup_regs; >>>> +=C2=A0=C2=A0=C2=A0 u32 *regs; >>>> +=C2=A0=C2=A0=C2=A0 u32 val; >>>> +=C2=A0=C2=A0=C2=A0 int i, j; >>>> + >>>> +=C2=A0=C2=A0=C2=A0 for (i =3D 0; i < pmx->nbanks; i++) { >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 regs =3D pmx->regs[i]; >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 for (j =3D 0; j < pmx->reg= _bank_size[i] / 4; j++) >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 wr= itel(*backup_regs++, regs++); >>>> +=C2=A0=C2=A0=C2=A0 } >>>> + >>>> +=C2=A0=C2=A0=C2=A0 if (pmx->soc->has_park_padcfg) { >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 val =3D pmx_readl(pmx, 0, = EMMC2_PAD_CFGPADCTRL_0); >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 val &=3D ~EMMC_DPD_PARKING= ; >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 pmx_writel(pmx, val, 0, EM= MC2_PAD_CFGPADCTRL_0); >>>> + >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 val =3D pmx_readl(pmx, 0, = EMMC4_PAD_CFGPADCTRL_0); >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 val &=3D ~EMMC_DPD_PARKING= ; >>>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 pmx_writel(pmx, val, 0, EM= MC4_PAD_CFGPADCTRL_0); >>>> +=C2=A0=C2=A0=C2=A0 } >>>> +} >>>> >>> But the CFGPADCTRL registers are already programmed by restoring the >>> backup_regs and hence the relevant EMMC's are already unparked. Hence >>> why do you need to force-unpark both of the EMMC's? What if EMMC is >>> unpopulated on a board, why do you need to unpark it then? >> PARK bit for EMMC2/EMMC4 (EMMC2_PAD_CFGPADCTRL and EMMC4_PAD_CFGPADCTRL) >> are not part of pinmux. >> >> They are part of CFGPADCTRL register so pinctrl driver pingroup doesn't >> include these registers. > I'm looking at the tegra210_groups and it clearly has these both > registers as a part of pinctrl setup because the rest of the bits > configure drive of the pads. > > From pinctrl-tegra210.c: > > #define DRV_PINGROUP_REG_A 0x8d4 /* bank 0 */ > > DRV_PINGROUP(sdmmc2, 0xa9c, 2, 6, 8, 6, 28, 2, 30, 2), > DRV_PINGROUP(sdmmc4, 0xab4, 2, 6, 8, 6, 28, 2, 30, 2), > > ... > > 0xa9c - 0x8d4 =3D 0x1c8 > 0xab4 - 0x8d4 =3D 0x1e0 > > Hence the PARK bits are already getting unset by restoring the > backup_regs because the CFGPADCTRL registers are a part of the "bank 0" > registers. > > Am I still missing something? DRV_PINGROUP parked_bit is -1 and will not be programmed so store and=20 restore will not take care of it. Also EMMC PADCFG is the only padcfg register which has parked bit and=20 for other IO pads its part of pinmux >> backup_regs doesn't take care of this and need to handled separately for >> Tegra210. >> >> >> During resume we have to clear PARK bit for the pads on Tegra210 and >> this is not related to presence/absence of eMMC on the board. > Okay, thank you for the clarification. > >> PAD is parked during LP0 entry to have it in DPD mode and it stays in >> DPD till its cleared by SW on resume. > Yes, this is documented in the public TRM. My main point is that it > looks like the PARK bits are unneedlessly getting unset twice in your > code (and it still looks like that to me).