From nobody Sun Dec 19 21:39:34 2021 X-Original-To: freebsd-arm@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 0D86E18FF5A1 for ; Sun, 19 Dec 2021 21:39:49 +0000 (UTC) (envelope-from mafsys1234@gmail.com) Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1D4" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4JHGMm6cpjz3C3s for ; Sun, 19 Dec 2021 21:39:48 +0000 (UTC) (envelope-from mafsys1234@gmail.com) Received: by mail-pj1-x102d.google.com with SMTP id rj2-20020a17090b3e8200b001b1944bad25so2642789pjb.5 for ; Sun, 19 Dec 2021 13:39:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=FskXSKjH50BAR3o4T954sJIAm/nVz3YRhe94cNJvB88=; b=iONfZoJRNqaT0T2NWAxsei/sY0xh355qlm7UNAx5YkQrMeRZ0C8vnOtsOaRCeX61nT b9smhZ20AZkCF2PM7k926TiuZKO0MogrhSRYyTa9/CIDvv5hgLtj/Q3kj7Ogn+FW1Jzl WSUX9ghHQClmMPBEWbAzKiKrVgWiNVVG8fFQSWUsNaRXB2oQ36GFgZm5vcOh8PVXy8Gw 1RzCurV4RreWJU0Z1TjnaR8LKryiqDKwWlWrsfo3qO2oDpvvUexeq5c4vI+kIHUwnTpf PWlcnCkq9DzHWP97pVUWnRxDsnX1FagYq8J6DP9Pajp5dN06RSJ1htYUXmG7J3EbQuZh 6GaA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=FskXSKjH50BAR3o4T954sJIAm/nVz3YRhe94cNJvB88=; b=38PxP48tE2Vzy0saZmKa+xAbzjBNm8AKcwQaAilUULRlTBMvQQGCom0blYf5KyBlxh fjrFm6zI/QsWLQkVG0H0AuEK75TlY7fmubNaHJvfnGySdDixGbfCfkYttXFTKgqYATIx RTPxEkVuQQVyfREst/meztYyC6z5W4LS28co5KuEAU9UmUKOJTtGL+1w+1NUlc3id3P7 8iJlMjemXm0S/2KyFoCqXHz8j1ahmpusZJv2nEBOAJdQU4+kEIwPtzCPU2rFSjIbZHcs DnMLrpkUW1dqddQP6ba5yjf9HFmPTEU+2w+8hZp0mZnAiahXWCP6cdYavK/oZ3ewJ4Oq epVA== X-Gm-Message-State: AOAM5339ZLnDqOShn7DI+P8Ij84bGcjG7IV3bPg+NwhXHsVGri6xbb3a kLR3Qxr+XDwksBpSnBDW7Myc3JW24gSZJQy1 X-Google-Smtp-Source: ABdhPJznTqqSFW13OskbyoZypvhCg1/CzarBDFX43YoBkdHL8dLpB4fl3VTKilLEsxKNSA+3RfXnyg== X-Received: by 2002:a17:90b:1d02:: with SMTP id on2mr3724184pjb.204.1639949981894; Sun, 19 Dec 2021 13:39:41 -0800 (PST) Received: from [192.168.1.10] ([115.69.53.183]) by smtp.gmail.com with ESMTPSA id m3sm14462124pgj.25.2021.12.19.13.39.40 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sun, 19 Dec 2021 13:39:41 -0800 (PST) Subject: Re: Dealing with slow USB disks, was: Re: Saving environment variables in u-boot To: bob prohaska Cc: freebsd-arm@freebsd.org References: <20211217013613.GA4452@www.zefox.net> <20211218005946.GA7670@www.zefox.net> <5C44D0E6-2FF1-4EEB-B21A-83333D6FCF46@yahoo.com> <9D416106-660F-40BB-98D2-1354B53D2FEF@yahoo.com> <20211218223543.GA9484@www.zefox.net> <6105a8a6-e760-2183-72fd-92e5a60aa8df@gmail.com> <20211219005134.GA12292@www.zefox.net> <4910504f-3051-9a95-d8e4-95434042196d@gmail.com> <20211219161816.GA14873@www.zefox.net> From: MJ Message-ID: <6edfdb4a-8ed3-7ef3-c3b2-7d2d7fd3206c@gmail.com> Date: Mon, 20 Dec 2021 08:39:34 +1100 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 List-Id: Porting FreeBSD to ARM processors List-Archive: https://lists.freebsd.org/archives/freebsd-arm List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-arm@freebsd.org MIME-Version: 1.0 In-Reply-To: <20211219161816.GA14873@www.zefox.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-AU Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4JHGMm6cpjz3C3s X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[] X-ThisMailContainsUnwantedMimeParts: N On 20/12/2021 3:18 am, bob prohaska wrote: > On Sun, Dec 19, 2021 at 10:03:47PM +1100, MJ wrote: >> >> I would think a mechanical USB is going to pull a "lot" of power when beginning spin-up, but once rotating should be easily powered by a USB hub. Though this would not explain how it works on RPI4 unless the powered hub you're using is USB2. >> > > That's what I thought too. I certainly didn't expect the disk to work > without a powered hub. The Pi4 is a different animal; it has USB3 ports > and more power available. That the mechanical disk works at all on the > Pi3's USB2 ports without assistance is quite surprising. See here: https://www.raspberrypi.com/documentation/computers/raspberry-pi.html#typical-power-requirements It mentions 1.2A, which covers your load, but, I would suspect if you attached, for example, a USB 'thumb' drive or other devices you would cause problems. > > There's a table at > https://hddfaqs.com/seagate-st1000lm048/ > listing power requirements for the drive: > Required Power For Spinup: 1000 mA > Power Required (Seek): 1.7 W > Power Required (Idle): 1.6 W > Power Required (Standby): 0.18 W The total draw capable will inevitably come down to the power supply unless, as you know, you use a powered hub (and even then, it depends on the hub's power output abilities). M