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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 EF680C28CBC for ; Wed, 6 May 2020 08:31:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D783820714 for ; Wed, 6 May 2020 08:31:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728829AbgEFIb4 (ORCPT ); Wed, 6 May 2020 04:31:56 -0400 Received: from mx2.suse.de ([195.135.220.15]:39174 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728732AbgEFIbz (ORCPT ); Wed, 6 May 2020 04:31:55 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 56620AC4A; Wed, 6 May 2020 08:31:56 +0000 (UTC) Message-ID: Subject: Re: [PATCH v3 1/2] arm: rpi: Add function to trigger VL805's firmware load From: Nicolas Saenz Julienne To: Bin Meng Cc: mbrugger@suse.com, U-Boot Mailing List , Marek Vasut , linux-kernel , Simon Glass , m.szyprowski@samsung.com, Sylwester Nawrocki , mark.kettenis@xs4all.nl Date: Wed, 06 May 2020 10:31:51 +0200 In-Reply-To: References: <20200505162607.334-1-nsaenzjulienne@suse.de> <20200505162607.334-2-nsaenzjulienne@suse.de> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-EaTpgXN83yDr3EDiIRK3" User-Agent: Evolution 3.36.2 MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-EaTpgXN83yDr3EDiIRK3 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Bin, On Wed, 2020-05-06 at 13:33 +0800, Bin Meng wrote: > Hi Nicolas, >=20 > On Wed, May 6, 2020 at 12:26 AM Nicolas Saenz Julienne > wrote: > > On the Raspberry Pi 4, after a PCI reset, VL805's (a xHCI chip) firmwar= e > > may either be loaded directly from an EEPROM or, if not present, by the > > SoC's VideCore (the SoC's co-processor). Introduce the function that > > informs VideCore that VL805 may need its firmware loaded. > >=20 >=20 > I still did not get it. Without the firmware being loaded, does xHCI > on RPi 4 still work? On newer revisions of RPi4, no, it will not work. > What exact functionality does the firmware provide? It provides xHCI functionality. The old RPi4 design loaded this vl805 firmware trough a dedicated EEPROM memory. But they removed it, probably in order to save costs. They then cre= ated this new interface to trigger a firmware load from RPi4's co-processor. Regards, Nicolas --=-EaTpgXN83yDr3EDiIRK3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEErOkkGDHCg2EbPcGjlfZmHno8x/4FAl6ydfcACgkQlfZmHno8 x/7ivggAt4hC6IOQmOjKnnlEb1k415vNhq/1A8H12ikDPTgDwb1KfxPkaGuWdIEm nnRIa4TmNiRnLV5V90EeEZGllgFuHLEcOrleX5iyLbxuZu9AuAPxxkR4qSBFYjM3 5JVrsMS+6yVulS8MV3WGEOEOH91etho4nOFKCeDIuKDaFo3YYGujpKJguvY6WVpo 2HwmqwJmYyotzuRcLF19ECfjVbk8hMEkj9y9SHwJUPYkbw+Pf6jrQ/6cTnIDnqfz gBi59lnx0epm86zB5eYHK1ecRjy1gWkab13ixQ1+UYhY4w6HyjPibmg6kz/nBheD X1dAFcnYj3rIkWQlM4QZ3uCeqD4NKA== =kORr -----END PGP SIGNATURE----- --=-EaTpgXN83yDr3EDiIRK3--