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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS autolearn=ham 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 4D57FC282DD for ; Sat, 20 Apr 2019 16:43:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 06CD320675 for ; Sat, 20 Apr 2019 16:43:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mj1ldbgd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728332AbfDTQnx (ORCPT ); Sat, 20 Apr 2019 12:43:53 -0400 Received: from mail-ed1-f67.google.com ([209.85.208.67]:34256 "EHLO mail-ed1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728271AbfDTQnx (ORCPT ); Sat, 20 Apr 2019 12:43:53 -0400 Received: by mail-ed1-f67.google.com with SMTP id a6so6654190edv.1 for ; Sat, 20 Apr 2019 09:43:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=to:from:subject:openpgp:message-id:date:user-agent:mime-version :content-language:content-transfer-encoding; bh=brUF2b+wAOM6SXOaF3N8J1yeIQAMPiB8AzAHPKqzNlg=; b=mj1ldbgdARfOfpNDlOdwimp7CrV4TPU1bAKEGt/s3Ta+0CinnpdTSgVUbrWC73FA4b GBfgOuyXwEJcUtuVBSrWofi5WLLkD6t5uK1CIS304hKuKnS7l/MgRXT8LXYb6TTC8pAn yif62ej47xUV7x4SSe1v5dopxHQlvi3Ww98X7HuKqkQ/dAuOEOFtTHfe2IY6/JQ2UUxL opFoJsJeGXctH/QIIeFnTbga1DKheb5yvbvuXxNv8u7jiY/0hxQXwdW/I7uyaQDqquiX NS2blmvJYm2K7/1V1YmRqD3a0HBjdCvQXOjwyy8DHbxwae4XxoORZrVfmvq8Id1HURxp Q/Zg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:from:subject:openpgp:message-id:date :user-agent:mime-version:content-language:content-transfer-encoding; bh=brUF2b+wAOM6SXOaF3N8J1yeIQAMPiB8AzAHPKqzNlg=; b=V60DsX2pDJHPWg9S4mxcFPURF9iqYYrgdqYIc8vbpOnTO5k7kxHej4zmQ+czC7dCla Lw9vGNfF268MSNFJx2rDYASneeYWctSFT45jOZHMrSDa4PwAjE+FaOF0bOgm/LdxNRLJ Ct9tAN371r67uWkZC7rSaGCXnX+qT1vlEFHjjsG+Mt8hQguF+ni8hcMMo0qtsW9rkzyr 9dlFERJQzuCavfm2Am/oDtYmoIR2BkUA9UmcNdl93JmOjRQnXkqsP0oc8XKZlRMt6Lek Am/zG957XBwztEGRabS3jOBUHFtIAHfbzuiCTH5FoUS/ysiDA449hQREyElXpsUd8997 sqSA== X-Gm-Message-State: APjAAAV6saDlhyzlxnUjyfG0mwkH4eSj9hXv7RgAz4MOPx2uB9tFodAq YExdJBrgriGyN4DqMvJBpRM= X-Google-Smtp-Source: APXvYqw4qpmGsw66lYfExFMGs8YUe8zJE9VWNgQPPpCcsETp6NF/65rKDX5wf8fyxlRjAAdps63wOQ== X-Received: by 2002:a05:6402:781:: with SMTP id d1mr6094521edy.286.1555778630956; Sat, 20 Apr 2019 09:43:50 -0700 (PDT) Received: from [10.230.1.150] ([192.19.228.250]) by smtp.gmail.com with ESMTPSA id w6sm1393186ejq.73.2019.04.20.09.43.49 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 20 Apr 2019 09:43:50 -0700 (PDT) To: Sudeep Holla , Guenter Roeck , linux-hwmon@vger.kernel.org, "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" From: Florian Fainelli Subject: SCMI sensor reads unit scaling Openpgp: preference=signencrypt Message-ID: <9207bc01-e0c6-ef73-6a24-6deda7b789c5@gmail.com> Date: Sat, 20 Apr 2019 09:43:48 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org Hi Sudeep, Guenter, The current SCMI hwmon support does not seem to make use of the sensor scale/unit as defined in the sensor replies (or the update scale for that matter). I came up with the patch below which gets the job done, but I am worried about possibly breaking people's SCMI deployments and sensors reading because they may have intentionally or not already decided to return a value which is scaled the way Linux's hwmon expect it, and may, or may not have populated a valid unit number in the sensor reply. Ideally we should probably do two conversions: - from within scmi_sensor_reading_get(), scale the value as indicated by the reply - from within scmi_hwmon_read(), take that scaled value and apply the necessary conversion expected by Linux's HWMON conventions (e.g.: reporting voltage as mV values) What do you think? --- From: Florian Fainelli Subject: firmware: arm_scmi: Support sensor scaling The SCMI sensor management protocol includes the following provision: The power-of-10 multiplier in two’s-complement format that is applied to the sensor unit specified by the SensorType field. Add support for scaling the value returned based on what is provided by the firmware. This requires us to be able to look up a sensor identifier to its backing scmi_sensor_info structure and apply the necessary scale. Signed-off-by: Florian Fainelli --- drivers/firmware/arm_scmi/sensors.c | 37 ++++++++++++++++++++++++++++++++++++- include/linux/scmi_protocol.h | 1 + 2 files changed, 37 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/arm_scmi/sensors.c b/drivers/firmware/arm_scmi/sensors.c index bbb469f..2eccc6a 100644 --- a/drivers/firmware/arm_scmi/sensors.c +++ b/drivers/firmware/arm_scmi/sensors.c @@ -33,7 +33,8 @@ struct scmi_msg_resp_sensor_description { #define NUM_TRIP_POINTS(x) (((x) >> 4) & 0xff) __le32 attributes_high; #define SENSOR_TYPE(x) ((x) & 0xff) -#define SENSOR_SCALE(x) (((x) >> 11) & 0x3f) +#define SENSOR_SCALE_MASK 0x3f +#define SENSOR_SCALE(x) (((x) >> 11) & SENSOR_SCALE_MASK) #define SENSOR_UPDATE_SCALE(x) (((x) >> 22) & 0x1f) #define SENSOR_UPDATE_BASE(x) (((x) >> 27) & 0x1f) u8 name[SCMI_MAX_STR_SIZE]; @@ -72,6 +73,35 @@ struct sensors_info { struct scmi_sensor_info *sensors; }; +static +struct scmi_sensor_info *scmi_sensor_info_from_id(struct sensors_info *si, + u32 sensor_id) +{ + struct scmi_sensor_info *s = NULL; + int i; + + for (i = 0; i < si->num_sensors; i++) { + s = &si->sensors[i]; + if (s->id == sensor_id) + return s; + } + + return s; +} + +static void inline scmi_scale_value(u8 scale, u64 *value) +{ + unsigned int i; + + if (scale & ((SENSOR_SCALE_MASK + 1) >> 1)) { + for (i = 0; i < (~scale) + 1; i++) + *value /= 10; + } else { + for (i = 0; i < scale; i++) + *value *= 10; + } +} + static int scmi_sensor_attributes_get(const struct scmi_handle *handle, struct sensors_info *si) { @@ -140,6 +170,7 @@ static int scmi_sensor_description_get(const struct scmi_handle *handle, s = &si->sensors[desc_index + cnt]; s->id = le32_to_cpu(buf->desc[cnt].id); s->type = SENSOR_TYPE(attrh); + s->scale = SENSOR_SCALE(attrh); memcpy(s->name, buf->desc[cnt].name, SCMI_MAX_STR_SIZE); } @@ -205,6 +236,8 @@ static int scmi_sensor_trip_point_set(const struct scmi_handle *handle, static int scmi_sensor_reading_get(const struct scmi_handle *handle, u32 sensor_id, bool async, u64 *value) { + struct sensors_info *si = handle->sensor_priv; + struct scmi_sensor_info *s = scmi_sensor_info_from_id(si, sensor_id); int ret; struct scmi_xfer *t; struct scmi_msg_sensor_reading_get *sensor; @@ -225,6 +258,8 @@ static int scmi_sensor_reading_get(const struct scmi_handle *handle, *value = le32_to_cpu(*pval); *value |= (u64)le32_to_cpu(*(pval + 1)) << 32; + if (s && s->scale) + scmi_scale_value(s->scale, value); } scmi_one_xfer_put(handle, t); diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index b458c87..782b53e 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -140,6 +140,7 @@ struct scmi_power_ops { struct scmi_sensor_info { u32 id; u8 type; + u8 scale; char name[SCMI_MAX_STR_SIZE]; }; -- -- Florian