From owner-freebsd-arm@freebsd.org Thu Mar 18 19:14:17 2021 Return-Path: Delivered-To: freebsd-arm@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 458255A9662 for ; Thu, 18 Mar 2021 19:14:17 +0000 (UTC) (envelope-from marklmi@yahoo.com) Received: from sonic315-55.consmr.mail.gq1.yahoo.com (sonic315-55.consmr.mail.gq1.yahoo.com [98.137.65.31]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4F1cCD2QFsz4clc for ; Thu, 18 Mar 2021 19:14:15 +0000 (UTC) (envelope-from marklmi@yahoo.com) X-SONIC-DKIM-SIGN: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1616094853; bh=OsNjGaCeyU0MwL4gBT+PQCb1pHOZeQQrtFXNuLL6Dzp=; h=X-Sonic-MF:Subject:From:Date:To:From:Subject; b=SB+Gw+yke2TNy7mDMiPg9IQn3sLykUZeN7sYymBhbj1GsV6jCAqhVTNfcYzz3mAHGNDwgbSiu5CGVU6Fc4jXOzxGyVw7zaBT62AAf+g4uFJ5XZLokA4Q45cBJLo/JUBpodDlBONfuPUf9ONCdx0NJE/OwLeVJsFdjSFMvfX8FpP1P5/LfLlsKZyUvLuNVbRjB/M0OAe1VXlBaHZPoBr2cM3/jmNJvsvGSMVQdSfgxU4UNDdzpiX88kMsk8TWV70TMnKEZ/G5l+yEhaokroo+iW5/hN1NlgOq8yVt7UuhVZEVOzVO48jJkkssfV1Vq7w2yzS3SbPYXDWMaQO9UIV7oA== X-YMail-OSG: .MEGxsMVM1mXlyCt.rMNAp1AAGt69dYnKCva6LkVBlen2KKMXzHOQLdMMJrCP_C 9bCCOYP1aBWKtPOADAy9xcYzfoZ7.IIEKYEZ.bTkfP0_eF1rcEPIR21SkjwjLWAJg3A1SkcLjMKR 5IuqiH9yvf62qU5QaaO1lpBFRjkmSjTfMrdWlIEvKnixYO0BQBWO7IW5.F2412H1ujXvILPJggY2 _ry1Zax1udezYjuZx.zCFh4iIROVZ2p.24YKnOOh5h0UCLhhcAreNbm.bd1wydxGxTsawFdQb2Fr eyGNIMYNxhz81tuexO38HY5JuFqPJWUm0mZtQIoPPIV9__XeEsc8IJBTL9sNK3x3oLJQu5F1.yAq pGymGw8vZbaWJyoCCc3gWKjNxMo_TxOTGFK.JbQ69C7bcfEJ0RWqDFvEhduS0B2dmmmd5YFFtnvS N8exqUnPSPbKo4CZ4CDjxZ3__QZewEfk4G3TcjvzEwISKVDDNtq7tizLDTQKgqGRnuXidsFPHT06 dj_uWB6icM3_vor4zBUhI84uTuWH113EMOuI6yXHmkidGn7a2EoB5A0hkctpp.w9Xol1p5yrj7mF GgLVMxR4v3H.Ts_jEJ_Sfb27IZ33rtvl6E_Ghqigoc7qgRRE.YV.Psjx6zuQbfYe2CRjMnSGbUQ2 s0XbJl44.96Y5YEUW.2hNp5Qo9gSiUAW0RLfpIbQI8TFRTCueQiX98dBBj9CZahWWfXn8cHnhWpF VdS0sXTaieadz6E61bK973YoANGBQAP0VdyLdiMRyl1ZTaovpWml0OH13whd4otYewN.6viiZJzb tS4Eiw5Ol0u3CXahz7WfMBJV10__0K7RHivJM.RqWibHzGWqxrT9jUNoClGHORMmM3ATLxzLjr1X sMH1FmuH4YfPpwViARkXJq1cqkU0YdJ2_KJWhFEpFCdifZtru.mQPT12.ZcGtqqOIbbBdJiRH_9y 5.bKWGyPyrTzzNT67FqkBKORBHg3o24dFrPN1LgMv1a_RDYiMnHD0RRrf_J_a5EKPSr8DUfjNL34 D.36OwIT.3qaEdq9EbrHYxIKMz1hve1eRxZDLHMdyTGT88xlZhDVMQekV0.dLm_bLGEvLM6Vr2Qa lpiqrKAgTBPE4lZt36xjSJCAPTACsfu5TnS92R3H1riGe5jFsHpS.C8KSiggZcyeQccaAt0B6shP 8djdDwF91vPo14_Z5peA4daFmhLuHPIhQlkJ8Af40zj0OLJjh1jqondMEZ7hYa4a.U9dCd5H4xNn lEVsCvWKby5iDWzxZ8PnDQDtK0fntTsBydPpMa39d2bXf6Eh5OZZpD5HIpOdaelo23hMVE9rUgCi PjByDj1eqSvxR6m1crquHTN26XtS4OFX3_XFrkMdIlw2R7JKS3F7Idyt85hRYvAMRACyVeXu5q80 tRFQobGHmm5zEs.7xikCYyHWPa94gFPj4b0yeke4HVPIwr.8IOOcbHJrNsJh6TC5CZeP5DLG16XA CLj5UMjLZajS4YEzVyXBWNkNCPutbE4RL0NaUzw4oIbZ1Sq7.NuJHcoJjM3Ev53URBvbogr6rDZa Nkde4kogxJviCQ1KxkS_VTzqTP8XmQcGdGjp6H3TChLlsxDUS7Kt7vUHUXM0Gv7HFKUv.FLEQT_i tZcWGVzECPKzDGPkoMXJaSlTyBB2EgG8UW9b0yHdOEhpVtQWNBHi4KvKT0neGwMDT3ba5J.7lXLq RdT10p2_kSOcyRQqC8Asy0S1_CoeAnjJN9D_nB.lrQjy1OLM3xGSIS6I1ES4ots6i8iEz34vdMWE P9CFMGjPbJqcgSC4vTfcN4z8eVFZmsZhExAdmeTggKsPj1WMGRd7vQLluMt5VuaF4vtwgh3I_cM6 RngZvN9q7CO.c9qYnyvTUdmPzi_Bv0VS3pQNuuN4rX0FaMt0xBer5uYaEcq2LB33ay6OWYu6Do0T 2mr16un0exXRH1ZQvxHeD9jr.DmEXrJE1lDT0UeaMK9ikS1TLVNKUryjsrdkmfZwzpwQyw6mhcZ_ UKNOOg4FCZS9zPWLc1pr8AnIIHWQ0oSjRk2QbTd4PpeY18txOy17agv2K1trl0QFO5brEhXG4oe0 Jjw0e5aMO5mrZeivMmnICVki82G5s3r10D.MdFJKktzZ9ZNGwSM6bqLOFvOIrEaitklpD4lGTBgA LSA3oFF313S_IQ2_3lsBEc8s9L3dlNylbmYz8urEYyBkNGl0wZ3wMV3WOlZveTLvbRcdFp.Xl16k uaSaC.luxTejZdq3oxA.G95r5eLbOREmuSMPzN0EoOlc93pDstEqq1K70VrOsF3HlM7yWDN.MYjU nEj6hmBR.rPfoXhsHose1XN.vxQk1FRAyJYo2ACBq8O0Wtktim_7GDp_.IqtgVJGEShCRAkmc4rd .6l_ttm29aBP6vznbyPNjp5VMI39lofapUWlpOysCg2mvsrBrj04nRO2GyJTvd0clPQFzuEvd3tU P.DtcBEQ3ACi1_v662ixScwWTVl.cuKmOP7Al8.vv1yWCWlD7NA-- X-Sonic-MF: Received: from sonic.gate.mail.ne1.yahoo.com by sonic315.consmr.mail.gq1.yahoo.com with HTTP; Thu, 18 Mar 2021 19:14:13 +0000 Received: by smtp411.mail.bf1.yahoo.com (VZM Hermes SMTP Server) with ESMTPA ID 8f0ef0c771b3df0f80a77655cfad10e1; Thu, 18 Mar 2021 19:14:10 +0000 (UTC) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.60.0.2.21\)) Subject: Re: RPI4 clock speeds and serial port From: Mark Millard In-Reply-To: <20210318180736.GA26853@www.zefox.net> Date: Thu, 18 Mar 2021 12:14:07 -0700 Cc: freebsd-arm@freebsd.org Content-Transfer-Encoding: 7bit Message-Id: <5F3752C0-F984-48CE-BA05-526A0C37C1FF@yahoo.com> References: <20210318170053.GA26688@www.zefox.net> <20210318180736.GA26853@www.zefox.net> To: bob prohaska X-Mailer: Apple Mail (2.3654.60.0.2.21) X-Rspamd-Queue-Id: 4F1cCD2QFsz4clc X-Spamd-Bar: --- X-Spamd-Result: default: False [-3.50 / 15.00]; TO_DN_SOME(0.00)[]; FREEMAIL_FROM(0.00)[yahoo.com]; MV_CASE(0.50)[]; R_SPF_ALLOW(-0.20)[+ptr:yahoo.com]; DKIM_TRACE(0.00)[yahoo.com:+]; RCPT_COUNT_TWO(0.00)[2]; DMARC_POLICY_ALLOW(-0.50)[yahoo.com,reject]; NEURAL_HAM_SHORT(-1.00)[-1.000]; FROM_EQ_ENVFROM(0.00)[]; RCVD_TLS_LAST(0.00)[]; MIME_TRACE(0.00)[0:+]; FREEMAIL_ENVFROM(0.00)[yahoo.com]; ASN(0.00)[asn:36647, ipnet:98.137.64.0/20, country:US]; RBL_DBL_DONT_QUERY_IPS(0.00)[98.137.65.31:from]; DWL_DNSWL_NONE(0.00)[yahoo.com:dkim]; MID_RHS_MATCH_FROM(0.00)[]; ARC_NA(0.00)[]; R_DKIM_ALLOW(-0.20)[yahoo.com:s=s2048]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; FROM_HAS_DN(0.00)[]; SH_EMAIL_DBL_DONT_QUERY_IPS(0.00)[0.0.0.0:email]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; SPAMHAUS_ZRD(0.00)[98.137.65.31:from:127.0.2.255]; TO_MATCH_ENVRCPT_SOME(0.00)[]; DBL_PROHIBIT(0.00)[0.0.0.0:email]; RCVD_IN_DNSWL_NONE(0.00)[98.137.65.31:from]; RWL_MAILSPIKE_POSSIBLE(0.00)[98.137.65.31:from]; RCVD_COUNT_TWO(0.00)[2]; MAILMAN_DEST(0.00)[freebsd-arm] X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Porting FreeBSD to ARM processors List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 18 Mar 2021 19:14:17 -0000 On 2021-Mar-18, at 11:07, bob prohaska wrote: > On Thu, Mar 18, 2021 at 05:28:27PM +0000, tech-lists wrote: >> hi, >> >> On Thu, Mar 18, 2021 at 10:00:53AM -0700, bob prohaska wrote: >> >>> /boot/msdos/config.txt contains >>> >>> root@nemesis:~ # more /boot/msdos/config.txt >>> [all] >>> arm_64bit=1 >>> dtparam=audio=on,i2c_arm=on,spi=on >>> dtoverlay=mmc >>> dtoverlay=disable-bt Note that use of disable-bt (which is something standard to my context as well). This switches would serial hardware is used, such that the hardware that is not cpu/gpu clock rate dependent is used. I forgot to mention this context in my prior reply. >>> device_tree_address=0x4000 >>> kernel=u-boot.bin >>> >>> [pi4] >>> #hdmi_safe=1 >>> armstub=armstub8-gic.bin >>> >>> Can one change the cpu speed without disturbing the serial console >>> by using something like >>> >>> arm_freq=1750 >>> >>> in config.txt, provided adequate cooling provisions are made? >> >> I have this config.txt on both a rpi4 stable/13 and main/14. I have a >> flirc case on stable/13 and one of those cases that looks like armour >> made from solid metal on main/rpi4. >> In both cases, the approved 5.1V @3.1W power supply is used. >> The highest temp I've seen under load is 72 degC and that's at 25 degC > > 72 C is rather toasty 8-) > >> ambient. On both machines my config.txt looks like this: >> >> arm_control=0x200 >> dtparam=audio=on,i2c_arm=on,spi=on >> dtoverlay=mmc >> dtoverlay=pwm >> dtoverlay=disable-bt >> device_tree_address=0x4000 >> kernel=u-boot.bin >> over_voltage=6 >> arm_freq=2000 >> sdram_freq_min=3200 >> >> In order to clock it, I need to enable powerd on startup in >> /etc/rc.conf: >> >> powerd_enable="YES" >> >> Because I also want that higher clock to run as much as possible, I tell >> powerd to have an absurdly low trigger to get the clocked speed: >> >> powerd_flags="-r 1" >> >> and here's the clocked speed: >> >> % sysctl -a | fgrep cpu.0 >> dev.cpu.0.temperature: 49.6C >> dev.cpu.0.freq_levels: 2000/-1 600/-1 >> dev.cpu.0.freq: 2000 >> dev.cpu.0.%parent: cpulist0 >> dev.cpu.0.%pnpinfo: name=cpu@0 compat=arm,cortex-a72 >> dev.cpu.0.%location: dev.cpu.0.%driver: cpu >> dev.cpu.0.%desc: Open Firmware CPU >> >>> I'd rather not complicate use of the serial console at this point >> >> not sure why the serial console would be a factor. I have a >> console-wired rpi4 running main/14 and I never considered it. I console >> into this machine like this: >> >> cu -l /dev/cuaU0 -s 115200 >> > > Maybe on FreeBSD it doesn't matter. Pi-related sites report that the > mini-UART baudrate is tied to the clock of the GPU, if that changes > the baudrate changes too. It wasn't clear to me if the speed-changes to > config.txt affected the GPU clock. Apparently not, at least in FreeBSD. You are correct that the mini-UART has the dependencies. But use of: dtoverlay=disable-bt avoids use of the mini-UART. The same is true of instead using: dtoverlay=miniuart-bt but, then, Bluetooth suffers the variability. (I just do not try to use Bluetooth.) === Mark Millard marklmi at yahoo.com ( dsl-only.net went away in early 2018-Mar)