From mboxrd@z Thu Jan 1 00:00:00 1970 From: Santosh Shilimkar Subject: Re: [PATCH 5/6] ARM: OMAP4: CLKDM: Update supported transition modes Date: Thu, 10 May 2012 12:24:27 +0530 Message-ID: <4FAB6623.9090005@ti.com> References: <1336599364-11024-1-git-send-email-jon-hunter@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from na3sys009aog133.obsmtp.com ([74.125.149.82]:44230 "EHLO na3sys009aog133.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756496Ab2EJGyj (ORCPT ); Thu, 10 May 2012 02:54:39 -0400 Received: by obbup19 with SMTP id up19so1768205obb.24 for ; Wed, 09 May 2012 23:54:33 -0700 (PDT) In-Reply-To: <1336599364-11024-1-git-send-email-jon-hunter@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Jon Hunter Cc: linux-omap , Ming Lei , Will Deacon , Benoit Cousson , Paul Walmsley , Kevin Hilman On Thursday 10 May 2012 03:06 AM, Jon Hunter wrote: > From: Jon Hunter > > For OMAP3+ devices, the clock domains (CLKDMs) support one or more of the > following transition modes ... > > NO_SLEEP (0x0) - A clock domain sleep transition is never initiated, > irrespective of the hardware conditions. > SW_SLEEP (0x1) - A software-forced sleep transition. The transition is initiated > when the associated hardware conditions are satisfied > SW_WKUP (0x2) - A software-forced clock domain wake-up transition is initiated, > irrespective of the hardware conditions. > HW_AUTO (0x3) - Hardware-controlled automatic sleep and wake-up transition is > initiated by the PRCM module when the associated hardware > conditions are satisfied. > > For OMAP4 devices, SW_SLEEP is equivalent to HW_AUTO and NO_SLEEP is equivalent > to SW_WKUP. For OMAP4 devices, all CLKDMs support HW_AUTO and therefore we can > place the CLKDMs in the HW_AUTO state instead of the SW_SLEEP mode. Hence, we > do not need to use the SW_SLEEP mode. With regard to NO_SLEEP and SW_WKUP it is > preferred to use SW_WKUP mode if the CLKDM supports it and so use this mode > instead of NO_SLEEP where possible. > > For a software perspective the above 4 modes are represented by the following > flags to indicate what modes are supported by each of the CLKDMs. > > CLKDM_CAN_DISABLE_AUTO --> NO_SLEEP > CLKDM_CAN_ENABLE_AUTO --> HW_AUTO > CLKDM_CAN_FORCE_SLEEP --> SW_SLEEP > CLKDM_CAN_FORCE_WAKEUP --> SW_WKUP > > By eliminating the SW_SLEEP mode the the mapping of the flags for OMAP4 devices > can becomes ... > > CLKDM_CAN_DISABLE_AUTO --> NO_SLEEP > CLKDM_CAN_ENABLE_AUTO --> HW_AUTO > CLKDM_CAN_FORCE_SLEEP --> HW_AUTO Not sure if this can be entirely correct for OMAP4. Because HW_AUTO = "Sleep and wakeup transition are based upon hardware conditions" Where as SW_SLEEP = "Start a software forced sleep transition on the domain." I will reply on the the thread where this is being discussed. > CLKDM_CAN_FORCE_WAKEUP --> SW_WKUP > > Cc: Ming Lei > Cc: Will Deacon > Cc: Benoit Cousson > Cc: Paul Walmsley > Cc: Kevin Hilman > > Signed-off-by: Jon Hunter > --- > arch/arm/mach-omap2/clockdomain44xx.c | 7 +++++-- > arch/arm/mach-omap2/cminst44xx.c | 14 -------------- > 2 files changed, 5 insertions(+), 16 deletions(-) > > diff --git a/arch/arm/mach-omap2/clockdomain44xx.c b/arch/arm/mach-omap2/clockdomain44xx.c > index 4f04dd1..99ce556 100644 > --- a/arch/arm/mach-omap2/clockdomain44xx.c > +++ b/arch/arm/mach-omap2/clockdomain44xx.c > @@ -70,7 +70,7 @@ static int omap4_clkdm_clear_all_wkup_sleep_deps(struct clockdomain *clkdm) > > static int omap4_clkdm_sleep(struct clockdomain *clkdm) > { > - omap4_cminst_clkdm_force_sleep(clkdm->prcm_partition, > + omap4_cminst_clkdm_enable_hwsup(clkdm->prcm_partition, > clkdm->cm_inst, clkdm->clkdm_offs); In case SW_SLEEP != HW_AUTO, something like below can be done if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP ) omap4_cminst_clkdm_force_sleep(clkdm->prcm_partition, clkdm->cm_inst, clkdm->clkdm_offs); else omap4_cminst_clkdm_enable_hwsup(clkdm->prcm_partition, clkdm->cm_inst, clkdm->clkdm_offs); > return 0; > } > @@ -90,7 +90,10 @@ static void omap4_clkdm_allow_idle(struct clockdomain *clkdm) > > static void omap4_clkdm_deny_idle(struct clockdomain *clkdm) > { > - omap4_cminst_clkdm_disable_hwsup(clkdm->prcm_partition, > + if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP) > + omap4_clkdm_wakeup(clkdm); > + else > + omap4_cminst_clkdm_disable_hwsup(clkdm->prcm_partition, > clkdm->cm_inst, clkdm->clkdm_offs); > } > > diff --git a/arch/arm/mach-omap2/cminst44xx.c b/arch/arm/mach-omap2/cminst44xx.c > index bd8810c..a44456c 100644 > --- a/arch/arm/mach-omap2/cminst44xx.c > +++ b/arch/arm/mach-omap2/cminst44xx.c > @@ -227,20 +227,6 @@ void omap4_cminst_clkdm_disable_hwsup(u8 part, s16 inst, u16 cdoffs) > } > > /** > - * omap4_cminst_clkdm_force_sleep - try to put a clockdomain into idle > - * @part: PRCM partition ID that the clockdomain registers exist in > - * @inst: CM instance register offset (*_INST macro) > - * @cdoffs: Clockdomain register offset (*_CDOFFS macro) > - * > - * Put a clockdomain referred to by (@part, @inst, @cdoffs) into idle > - * No return value. > - */ > -void omap4_cminst_clkdm_force_sleep(u8 part, s16 inst, u16 cdoffs) > -{ > - _clktrctrl_write(OMAP34XX_CLKSTCTRL_FORCE_SLEEP, part, inst, cdoffs); > -} > - > -/** > * omap4_cminst_clkdm_force_sleep - try to take a clockdomain out of idle > * @part: PRCM partition ID that the clockdomain registers exist in > * @inst: CM instance register offset (*_INST macro)