From nobody Wed Jun 21 13:55:51 2023 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 4QmQ5N1pLXz4gNPl for ; Wed, 21 Jun 2023 13:56:08 +0000 (UTC) (envelope-from manu@bidouilliste.com) Received: from mx.blih.net (mx.blih.net [212.83.155.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "mx.blih.net", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4QmQ5K6DfSz3y1L for ; Wed, 21 Jun 2023 13:56:05 +0000 (UTC) (envelope-from manu@bidouilliste.com) Authentication-Results: mx1.freebsd.org; none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bidouilliste.com; s=mx; t=1687355757; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=9dv1EDiMGdEXDLrDsExNOQ79bx6JGGvTEYTb/A9H6e0=; b=oHnBafhHSkYtQecalJNlTD59XIs8E5CsFhKP0NDrr+9tWynD4pFxDxMgfBefhzv9/zIjZH HsZQ35P1Yn8LCwvdWHw45f/12+6v1aUUQDZ4hcbL47vOAr3sRIiu0HZ5fHeu9MyCvWq1/9 JEcOjBm4C6lEOaeOg+35+kEkzvpjqW4= Received: from skull.home.blih.net (lfbn-lyo-1-2174-135.w90-66.abo.wanadoo.fr [90.66.97.135]) by mx.blih.net (OpenSMTPD) with ESMTPSA id 6403a1ad (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Wed, 21 Jun 2023 13:55:53 +0000 (UTC) Date: Wed, 21 Jun 2023 15:55:51 +0200 From: Emmanuel Vadot To: titus Cc: freebsd-arm@freebsd.org Subject: Re: h616 clocks Message-Id: <20230621155551.5c6a2db2ad87c08c7d2ec7f2@bidouilliste.com> In-Reply-To: References: X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; amd64-portbld-freebsd14.0) 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 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 4QmQ5K6DfSz3y1L X-Spamd-Bar: ---- X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:12876, ipnet:212.83.128.0/19, country:FR] X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-ThisMailContainsUnwantedMimeParts: N Hello Titus, On Wed, 21 Jun 2023 10:58:17 +0300 titus wrote: > I?m trying to add support for allwinner H616 ccu > I downloaded H616 user manual and i mostly can figure out differences fro= m allwinner H6 but i have a question > how is the CCU_GATE clock parent assigned to a specifc ccu gate - there i= s no indication in the manual There is, you need to look at the system bus tree (page 90 for the H6 and page 46 for the H616). > for example=20 > CCU_GATE(CLK_BUS_DE, "bus-de", "psi-ahb1-ahb2", 0x60c, 0) > the manual says that > 0x060C DE Bus Gating Reset Register (Default Value: 0x0000_0000) has bit = 0 as DE_GATING and bit 16 as DE_RST > but why is psi-ahb1-ahb2 chosen as parent ? (can?t find any reference in = the manual) No idea where you got this example as we don't have this clock defined in FreeBSD so a bit hard to answer to this specific example. But indeed that looks correct as the DE engine sits on the PSI2AHB bus which is on the PSI bus. If you look at page 91 in the H6 user manual you can see that AHB1 and AHB2 are both the same clock and equal to the PSI one, which itself is created from 4 possible parents (OSC24M, CCU_32K, RC16M and PLL_PERI0) and two factors (N and M). Clocks can be a bit hard to understand, especially clock topology and Allwinner doesn't make it better by not having a full clock topo table in their docs usually. So open the doc 3 or 4 times and go back and forth reading the clock tree and register definitions. Also don't hesitate to ask more questions I'll see if I can help. Cheers, --=20 Emmanuel Vadot