Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753462AbdLSWZu (ORCPT ); Tue, 19 Dec 2017 17:25:50 -0500 Received: from mail.free-electrons.com ([62.4.15.54]:42872 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753421AbdLSWZq (ORCPT ); Tue, 19 Dec 2017 17:25:46 -0500 Date: Tue, 19 Dec 2017 23:25:35 +0100 From: Alexandre Belloni To: Romain Izard Cc: Boris Brezillon , Michael Turquette , Stephen Boyd , Nicolas Ferre , Ludovic Desroches , linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v6 3/3] clk: at91: pmc: Support backup for programmable clocks Message-ID: <20171219222535.GU15162@piout.net> References: <20171211165535.5126-1-romain.izard.pro@gmail.com> <20171211165535.5126-4-romain.izard.pro@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171211165535.5126-4-romain.izard.pro@gmail.com> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4468 Lines: 155 On 11/12/2017 at 17:55:35 +0100, Romain Izard wrote: > When an AT91 programmable clock is declared in the device tree, register > it into the Power Management Controller driver. On entering suspend mode, > the driver saves and restores the Programmable Clock registers to support > the backup mode for these clocks. > > Signed-off-by: Romain Izard > Acked-by: Nicolas Ferre Acked-by: Alexandre Belloni > --- > Changes in v2: > * register PCKs on clock startup > > Changes in v3: > * improve comments on hanling 0 in pmc_register_id and pmc_register_pck > * declare local variables earlier for checkpatch > > Changes in v6: > * Use the correct author email address > > drivers/clk/at91/clk-programmable.c | 2 ++ > drivers/clk/at91/pmc.c | 35 +++++++++++++++++++++++++++++++++++ > drivers/clk/at91/pmc.h | 2 ++ > 3 files changed, 39 insertions(+) > > diff --git a/drivers/clk/at91/clk-programmable.c b/drivers/clk/at91/clk-programmable.c > index 85a449cf61e3..0e6aab1252fc 100644 > --- a/drivers/clk/at91/clk-programmable.c > +++ b/drivers/clk/at91/clk-programmable.c > @@ -204,6 +204,8 @@ at91_clk_register_programmable(struct regmap *regmap, > if (ret) { > kfree(prog); > hw = ERR_PTR(ret); > + } else { > + pmc_register_pck(id); > } > > return hw; > diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c > index 07dc2861ad3f..1fa27f4ea538 100644 > --- a/drivers/clk/at91/pmc.c > +++ b/drivers/clk/at91/pmc.c > @@ -22,6 +22,7 @@ > #include "pmc.h" > > #define PMC_MAX_IDS 128 > +#define PMC_MAX_PCKS 8 > > int of_at91_get_clk_range(struct device_node *np, const char *propname, > struct clk_range *range) > @@ -50,6 +51,7 @@ EXPORT_SYMBOL_GPL(of_at91_get_clk_range); > static struct regmap *pmcreg; > > static u8 registered_ids[PMC_MAX_IDS]; > +static u8 registered_pcks[PMC_MAX_PCKS]; > > static struct > { > @@ -66,8 +68,13 @@ static struct > u32 pcr[PMC_MAX_IDS]; > u32 audio_pll0; > u32 audio_pll1; > + u32 pckr[PMC_MAX_PCKS]; > } pmc_cache; > > +/* > + * As Peripheral ID 0 is invalid on AT91 chips, the identifier is stored > + * without alteration in the table, and 0 is for unused clocks. > + */ > void pmc_register_id(u8 id) > { > int i; > @@ -82,9 +89,28 @@ void pmc_register_id(u8 id) > } > } > > +/* > + * As Programmable Clock 0 is valid on AT91 chips, there is an offset > + * of 1 between the stored value and the real clock ID. > + */ > +void pmc_register_pck(u8 pck) > +{ > + int i; > + > + for (i = 0; i < PMC_MAX_PCKS; i++) { > + if (registered_pcks[i] == 0) { > + registered_pcks[i] = pck + 1; > + break; > + } > + if (registered_pcks[i] == (pck + 1)) > + break; > + } > +} > + > static int pmc_suspend(void) > { > int i; > + u8 num; > > regmap_read(pmcreg, AT91_PMC_SCSR, &pmc_cache.scsr); > regmap_read(pmcreg, AT91_PMC_PCSR, &pmc_cache.pcsr0); > @@ -103,6 +129,10 @@ static int pmc_suspend(void) > regmap_read(pmcreg, AT91_PMC_PCR, > &pmc_cache.pcr[registered_ids[i]]); > } > + for (i = 0; registered_pcks[i]; i++) { > + num = registered_pcks[i] - 1; > + regmap_read(pmcreg, AT91_PMC_PCKR(num), &pmc_cache.pckr[num]); > + } > > return 0; > } > @@ -119,6 +149,7 @@ static bool pmc_ready(unsigned int mask) > static void pmc_resume(void) > { > int i; > + u8 num; > u32 tmp; > u32 mask = AT91_PMC_MCKRDY | AT91_PMC_LOCKA; > > @@ -143,6 +174,10 @@ static void pmc_resume(void) > pmc_cache.pcr[registered_ids[i]] | > AT91_PMC_PCR_CMD); > } > + for (i = 0; registered_pcks[i]; i++) { > + num = registered_pcks[i] - 1; > + regmap_write(pmcreg, AT91_PMC_PCKR(num), pmc_cache.pckr[num]); > + } > > if (pmc_cache.uckr & AT91_PMC_UPLLEN) > mask |= AT91_PMC_LOCKU; > diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h > index 858e8ef7e8db..d22b1fa9ecdc 100644 > --- a/drivers/clk/at91/pmc.h > +++ b/drivers/clk/at91/pmc.h > @@ -31,8 +31,10 @@ int of_at91_get_clk_range(struct device_node *np, const char *propname, > > #ifdef CONFIG_PM > void pmc_register_id(u8 id); > +void pmc_register_pck(u8 pck); > #else > static inline void pmc_register_id(u8 id) {} > +static inline void pmc_register_pck(u8 pck) {} > #endif > > #endif /* __PMC_H_ */ > -- > 2.14.1 > -- Alexandre Belloni, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com