Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031613AbcCQQyt (ORCPT ); Thu, 17 Mar 2016 12:54:49 -0400 Received: from down.free-electrons.com ([37.187.137.238]:53655 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1031254AbcCQQyp (ORCPT ); Thu, 17 Mar 2016 12:54:45 -0400 Date: Thu, 17 Mar 2016 17:54:42 +0100 From: Alexandre Belloni To: Wenyou Yang Cc: Nicolas Ferre , Jean-Christophe Plagniol-Villard , Russell King , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org, Rob Herring , Pawel Moll , Mark Brown , Ian Campbell , Kumar Gala Subject: Re: [PATCH v5 2/5] ARM: at91: pm: add ULP1 mode support Message-ID: <20160317165442.GC2831@piout.net> References: <1458111489-23774-1-git-send-email-wenyou.yang@atmel.com> <1458111489-23774-3-git-send-email-wenyou.yang@atmel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1458111489-23774-3-git-send-email-wenyou.yang@atmel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3881 Lines: 135 On 16/03/2016 at 14:58:06 +0800, Wenyou Yang wrote : > @@ -497,4 +506,7 @@ void __init sama5_pm_init(void) > at91_pm_data.uhp_udp_mask = AT91SAM926x_PMC_UHP | AT91SAM926x_PMC_UDP; > at91_pm_data.memctrl = AT91_MEMCTRL_DDRSDR; > at91_pm_init(NULL); > + > + if (readl(pmc + AT91_PMC_VERSION) >= SAMA5D2_PMC_VERSION) I would not use that. Instead, I would create a new function, sama5d2_pm_init() and call it from sama5.c with a new sama5d2_dt_device_init and a new DT_MACHINE. > + at91_pm_data.ulp_mode = ULP1_MODE; > } > diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h > index 3fcf881..2e76745 100644 > --- a/arch/arm/mach-at91/pm.h > +++ b/arch/arm/mach-at91/pm.h > @@ -39,4 +39,11 @@ extern void __iomem *at91_ramc_base[]; > > #define AT91_PM_SLOW_CLOCK 0x01 > > +#define AT91_PM_ULP_OFFSET 5 > +#define AT91_PM_ULP_MASK 0x03 > +#define AT91_PM_ULP(x) (((x) & AT91_PM_ULP_MASK) << AT91_PM_ULP_OFFSET) > + > +#define AT91_PM_ULP0_MODE 0x00 > +#define AT91_PM_ULP1_MODE 0x01 > + > #endif > diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S > index 5fcffdc..f2a5c4b 100644 > --- a/arch/arm/mach-at91/pm_suspend.S > +++ b/arch/arm/mach-at91/pm_suspend.S > @@ -41,6 +41,15 @@ tmp2 .req r5 > .endm > > /* > + * Wait for main oscillator selection is done > + */ > + .macro wait_moscsels > +1: ldr tmp1, [pmc, #AT91_PMC_SR] > + tst tmp1, #AT91_PMC_MOSCSELS > + beq 1b > + .endm > + > +/* > * Wait until PLLA has locked. > */ > .macro wait_pllalock > @@ -101,6 +110,10 @@ ENTRY(at91_pm_suspend_in_sram) > and r0, r0, #AT91_PM_MODE_MASK > str r0, .pm_mode > > + lsr r0, r3, #AT91_PM_ULP_OFFSET > + and r0, r0, #AT91_PM_ULP_MASK > + str r0, .ulp_mode > + > /* Active the self-refresh mode */ > mov r0, #SRAMC_SELF_FRESH_ACTIVE > bl at91_sramc_self_refresh > @@ -131,6 +144,13 @@ ENTRY(at91_pm_suspend_in_sram) > orr tmp1, tmp1, #(1 << 29) /* bit 29 always set */ > str tmp1, [pmc, #AT91_CKGR_PLLAR] > > + ldr r0, .ulp_mode > + tst r0, #AT91_PM_ULP1_MODE > + beq ulp0_mode > + > + bl at91_pm_ulp1_mode > + b ulp_exit > + > ulp0_mode: > bl at91_pm_ulp0_mode > b ulp_exit > @@ -326,6 +346,81 @@ ENTRY(at91_pm_ulp0_mode) > mov pc, lr > ENDPROC(at91_pm_ulp0_mode) > > +/* > + * void at91_pm_ulp1_mode(void) > + */ > +ENTRY(at91_pm_ulp1_mode) > + ldr pmc, .pmc_base > + > + /* Switch the main clock source to 12-MHz RC oscillator */ > + ldr tmp1, [pmc, #AT91_CKGR_MOR] > + bic tmp1, tmp1, #AT91_PMC_MOSCSEL > + bic tmp1, tmp1, #AT91_PMC_KEY_MASK > + orr tmp1, tmp1, #AT91_PMC_KEY > + str tmp1, [pmc, #AT91_CKGR_MOR] > + > + wait_moscsels > + > + /* Disable the crystal oscillator */ > + ldr tmp1, [pmc, #AT91_CKGR_MOR] > + bic tmp1, tmp1, #AT91_PMC_MOSCEN > + bic tmp1, tmp1, #AT91_PMC_KEY_MASK > + orr tmp1, tmp1, #AT91_PMC_KEY > + str tmp1, [pmc, #AT91_CKGR_MOR] > + > + /* Switch the master clock source to main clock */ > + ldr tmp1, [pmc, #AT91_PMC_MCKR] > + bic tmp1, tmp1, #AT91_PMC_CSS > + orr tmp1, tmp1, #AT91_PMC_CSS_MAIN > + str tmp1, [pmc, #AT91_PMC_MCKR] > + > + wait_mckrdy > + > + /* Enter the ULP1 mode by set WAITMODE bit in CKGR_MOR */ > + ldr tmp1, [pmc, #AT91_CKGR_MOR] > + orr tmp1, tmp1, #AT91_PMC_WAITMODE > + bic tmp1, tmp1, #AT91_PMC_KEY_MASK > + orr tmp1, tmp1, #AT91_PMC_KEY > + str tmp1, [pmc, #AT91_CKGR_MOR] > + > + wait_mckrdy > + > + /* Enable the crystal oscillator */ > + ldr tmp1, [pmc, #AT91_CKGR_MOR] > + orr tmp1, tmp1, #AT91_PMC_MOSCEN > + bic tmp1, tmp1, #AT91_PMC_KEY_MASK > + orr tmp1, tmp1, #AT91_PMC_KEY > + str tmp1, [pmc, #AT91_CKGR_MOR] > + This will badly fail on the platforms that don't populate a crystal for the main clock or use the bypass. I think wee need to have at least a comment or save the previous state and restore it. -- Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com