From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1B53C35DF5 for ; Tue, 25 Feb 2020 11:03:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 80B43246A3 for ; Tue, 25 Feb 2020 11:03:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730003AbgBYLDv (ORCPT ); Tue, 25 Feb 2020 06:03:51 -0500 Received: from foss.arm.com ([217.140.110.172]:49180 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729287AbgBYLDv (ORCPT ); Tue, 25 Feb 2020 06:03:51 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E57B131B; Tue, 25 Feb 2020 03:03:49 -0800 (PST) Received: from bogus (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7BACA3F6CF; Tue, 25 Feb 2020 03:03:48 -0800 (PST) Date: Tue, 25 Feb 2020 11:03:46 +0000 From: Sudeep Holla To: Elliot Berman Cc: Mark Rutland , Lorenzo Pieralisi , Bjorn Andersson , Trilok Soni , Prasad Sodagudi , David Collins , Sudeep Holla , linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/3] firmware: psci: Add support for dt-supplied SYSTEM_RESET2 type Message-ID: <20200225110346.GF32784@bogus> References: <1582577858-12410-1-git-send-email-eberman@codeaurora.org> <1582577858-12410-3-git-send-email-eberman@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1582577858-12410-3-git-send-email-eberman@codeaurora.org> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 24, 2020 at 12:57:37PM -0800, Elliot Berman wrote: > Some implementors of PSCI may relax the requirements of the PSCI > architectural warm reset. In order to comply with PSCI specification, a > different reset_type value must be used. The alternate PSCI > SYSTEM_RESET2 may be used in all warm/soft reboot scenarios, replacing > the architectural warm reset. > > Signed-off-by: Elliot Berman > --- > drivers/firmware/psci/psci.c | 22 ++++++++++++++++++---- > include/uapi/linux/psci.h | 2 ++ > 2 files changed, 20 insertions(+), 4 deletions(-) > > diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c > index 2937d44..8f4609c 100644 > --- a/drivers/firmware/psci/psci.c > +++ b/drivers/firmware/psci/psci.c > @@ -90,6 +90,8 @@ static u32 psci_function_id[PSCI_FN_MAX]; > > static u32 psci_cpu_suspend_feature; > static bool psci_system_reset2_supported; > +static u32 psci_sys_reset2_reset_param = > + PSCI_1_1_SYSTEM_RESET2_SYSTEM_WARM_RESET; > > static inline bool psci_has_ext_power_state(void) > { > @@ -272,11 +274,10 @@ static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd) > if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) && > psci_system_reset2_supported) { > /* > - * reset_type[31] = 0 (architectural) > - * reset_type[30:0] = 0 (SYSTEM_WARM_RESET) Sorry for missing this earlier, you can move this comment above if others agree to not drop that info. I am fine with removing it too. E > * cookie = 0 (ignored by the implementation) > */ > - invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0); > + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), > + psci_sys_reset2_reset_param, 0, 0); > } else { > invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0); > } > @@ -493,6 +494,7 @@ typedef int (*psci_initcall_t)(const struct device_node *); > static int __init psci_0_2_init(struct device_node *np) > { > int err; > + u32 param; > > err = get_set_conduit_method(np); > if (err) > @@ -505,7 +507,19 @@ static int __init psci_0_2_init(struct device_node *np) > * can be carried out according to the specific version reported > * by firmware > */ > - return psci_probe(); > + err = psci_probe(); > + if (err) > + return err; > + > + if (psci_system_reset2_supported && > + !of_property_read_u32(np, "arm,psci-sys-reset2-param", ¶m)) { > + if ((s32)param > 0) What is the point on signed comparison here ? You are assuming all vendor reset also as architecture by doing so which is wrong. > + pr_warn("%08x is an invalid architectural reset type.\n", > + param); I thought the point was to have vendor reset here. Based on the 3/3 you see to have vendor reset bit set, you ignore that by doing signed comparison which is wrong and even the message is wrong. Specification defines only one architectural reset(WARM RESET) and all others need to be vendor specific. -- Regards, Sudeep