From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lina Iyer Subject: Re: [PATCH 11/14] drivers: firmware: psci: Allow OS Initiated suspend mode Date: Fri, 24 Jun 2016 10:53:29 -0600 Message-ID: <20160624165329.GA1085@linaro.org> References: <1466624209-27432-1-git-send-email-lina.iyer@linaro.org> <1466624209-27432-12-git-send-email-lina.iyer@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Return-path: Received: from mail-pf0-f180.google.com ([209.85.192.180]:36207 "EHLO mail-pf0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751706AbcFXQxt (ORCPT ); Fri, 24 Jun 2016 12:53:49 -0400 Received: by mail-pf0-f180.google.com with SMTP id t190so40865625pfb.3 for ; Fri, 24 Jun 2016 09:53:33 -0700 (PDT) Content-Disposition: inline In-Reply-To: Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Vikas Sajjan Cc: ulf.hansson@linaro.org, Kevin Hilman , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, "linux-arm-kernel@lists.infradead.org" , Mark Rutland , k.kozlowski@samsung.com, Lorenzo Pieralisi , ahaslam@baylibre.com, linux-arm-msm@vger.kernel.org, sboyd@codeaurora.org, geert@linux-m68k.org, andy.gross@linaro.org, mtitinger@baylibre.com On Fri, Jun 24 2016 at 22:25 -0600, Vikas Sajjan wrote: >Hi Lina, > >On Thu, Jun 23, 2016 at 1:06 AM, Lina Iyer wrote: >> PSCI firmware v1.0 onwards may support 2 different modes for >> CPU_SUSPEND. Platform coordinated mode is the default and every firmware >> should support it. OS Initiated mode is optional for the firmware to >> implement and allow Linux to make an better decision on the state of >> the CPU cluster heirarchy. >> >> With the kernel capable of deciding the state for CPU cluster and >> coherency domains, the OS Initiated mode may now be used by the kernel, >> provided the firmware supports it. SET_SUSPEND_MODE is a PSCI function >> available on v1.0 onwards and can be used to set the mode in the >> firmware. >> >> Cc: Lorenzo Pieralisi >> Cc: Mark Rutland >> Signed-off-by: Lina Iyer >> [Ulf: Rebased on 4.7 rc1] >> Signed-off-by: Ulf Hansson >> --- >> drivers/firmware/psci.c | 22 +++++++++++++++++++++- >> include/uapi/linux/psci.h | 5 +++++ >> 2 files changed, 26 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c >> index 03e0458..3920aba 100644 >> --- a/drivers/firmware/psci.c >> +++ b/drivers/firmware/psci.c >> @@ -52,6 +52,7 @@ >> * require cooperation with a Trusted OS driver. >> */ >> static int resident_cpu = -1; >> +static bool psci_has_osi_pd; >> >> bool psci_tos_resident_on(int cpu) >> { >> @@ -563,10 +564,29 @@ out_put_node: >> return err; >> } >> >> +static int __init psci_1_0_init(struct device_node *np) >> +{ >> + int ret; >> + >> + ret = psci_0_2_init(np); >> + if (ret) >> + return ret; >> + >> + /* Check if PSCI OSI mode is available */ >> + ret = psci_features(psci_function_id[PSCI_FN_CPU_SUSPEND]); >> + if (ret & PSCI_1_0_OS_INITIATED) { >> + ret = psci_features(PSCI_1_0_FN_SET_SUSPEND_MODE); >> + if (!ret) >> + psci_has_osi_pd = true; > >IMHO, its better to have this done in psci_init_cpu_suspend() itself >for 2 reasons > >a] psci_init_cpu_suspend() already calls >psci_features(psci_function_id[PSCI_FN_CPU_SUSPEND]) >b] by moving this in psci_init_cpu_suspend() we make this support >available even for ACPI platforms, since psci_acpi_init() calls >psci_probe() and this calls psci_init_cpu_suspend() for >PSCI_VERSION_MAJOR(ver) >= 1 > Hmmm.. I can do that. Thanks, Lina >I even posted a patch [1] yesterday, without being aware of your >patchset for the same. > >[1] http://www.spinics.net/lists/arm-kernel/msg513682.html > > >> + } >> + >> + return 0; >> +} >> + >> static const struct of_device_id psci_of_match[] __initconst = { >> { .compatible = "arm,psci", .data = psci_0_1_init}, >> { .compatible = "arm,psci-0.2", .data = psci_0_2_init}, >> - { .compatible = "arm,psci-1.0", .data = psci_0_2_init}, >> + { .compatible = "arm,psci-1.0", .data = psci_1_0_init}, >> {}, >> }; >> >> diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h >> index 3d7a0fc..7dd778e 100644 >> --- a/include/uapi/linux/psci.h >> +++ b/include/uapi/linux/psci.h >> @@ -48,6 +48,7 @@ >> >> #define PSCI_1_0_FN_PSCI_FEATURES PSCI_0_2_FN(10) >> #define PSCI_1_0_FN_SYSTEM_SUSPEND PSCI_0_2_FN(14) >> +#define PSCI_1_0_FN_SET_SUSPEND_MODE PSCI_0_2_FN(15) >> >> #define PSCI_1_0_FN64_SYSTEM_SUSPEND PSCI_0_2_FN64(14) >> >> @@ -93,6 +94,10 @@ >> #define PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK \ >> (0x1 << PSCI_1_0_FEATURES_CPU_SUSPEND_PF_SHIFT) >> >> +#define PSCI_1_0_OS_INITIATED BIT(0) >> +#define PSCI_1_0_SUSPEND_MODE_PC 0 >> +#define PSCI_1_0_SUSPEND_MODE_OSI 1 >> + >> /* PSCI return values (inclusive of all PSCI versions) */ >> #define PSCI_RET_SUCCESS 0 >> #define PSCI_RET_NOT_SUPPORTED -1 >> -- >> 2.7.4 >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel