From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Stuebner Subject: Re: [PATCH] drm/rockchip: fix for mailbox read size Date: Mon, 19 Nov 2018 15:18:33 +0100 Message-ID: <7088529.fTnRXqZmiP@phil> References: <1541518625-25984-1-git-send-email-dkos@cadence.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <1541518625-25984-1-git-send-email-dkos@cadence.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Damian Kos Cc: David Airlie , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org, Chris Zhong , linux-arm-kernel@lists.infradead.org List-Id: linux-rockchip.vger.kernel.org QW0gRGllbnN0YWcsIDYuIE5vdmVtYmVyIDIwMTgsIDE2OjM3OjA1IENFVCBzY2hyaWViIERhbWlh biBLb3M6Cj4gU29tZSBvZiB0aGUgZnVuY3Rpb25zIChsaWtlIGNkbl9kcF9kcGNkX3JlYWQsIGNk bl9kcF9nZXRfZWRpZF9ibG9jaykKPiBhbGxvdyB0byByZWFkIDY0S2lCLCBidXQgdGhlIGNkbl9k cF9tYWlsYm94X3JlYWRfcmVjZWl2ZSwgdGhhdCBpcwo+IHVzZWQgYnkgdGhlbSwgY2FuIHJlYWQg b25seSB1cCB0byAyNTUgYnl0ZXMgYXQgb25jZS4gTm9ybWFsbHksIGl0J3MKPiBub3QgYSBiaWcg aXNzdWUgYXMgRFBDRCBvciBFRElEIHJlYWRzIHdvbid0IChob3BlZnVsbHkpIGV4Y2VlZCB0aGF0 Cj4gdmFsdWUuCj4gVGhlIHJlYWwgaXNzdWUgaGVyZSBpcyB0aGUgcmV2b2NhdGlvbiBsaXN0IHJl YWQgZHVyaW5nIHRoZSBIRENQCj4gYXV0aGVudGljYXRpb24gcHJvY2Vzcy4gKHByb2JsZW1hdGlj IHVzZSBjYXNlOgo+IGh0dHBzOi8vY2hyb21pdW0uZ29vZ2xlc291cmNlLmNvbS9jaHJvbWl1bW9z L3RoaXJkX3BhcnR5L2tlcm5lbC8rL2Nocm9tZW9zLTQuNC9kcml2ZXJzL2dwdS9kcm0vcm9ja2No aXAvY2RuLWRwLXJlZy5jIzExNTIpCj4gVGhlIGxpc3QgY2FuIHJlYWNoIDEyNyo1KzQgYnl0ZXMg KG51bSBkZXZzICogNSBieXRlcyBwZXIgSUQvQmtzdiArCj4gNCBieXRlcyBvZiBhbiBhZGRpdGlv bmFsIGluZm8pLgo+IEluIG90aGVyIHdvcmRzIC0gQ1RTZXMgd2l0aCBIRENQIFJlcGVhdGVyIHdv bid0IHBhc3Mgd2l0aG91dCB0aGlzCj4gZml4LiBPaCwgYW5kIHRoZSBkcml2ZXIgd2lsbCBtb3N0 IGxpa2VseSBzdG9wIHdvcmtpbmcgKGJlc3QgY2FzZQo+IHNjZW5hcmlvKS4KPiAKPiBTaWduZWQt b2ZmLWJ5OiBEYW1pYW4gS29zIDxka29zQGNhZGVuY2UuY29tPgoKYXBwbGllZCB0byBkcm0tbWlz Yy1uZXh0CgpUaGFua3MKSGVpa28KCgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZlbEBsaXN0cy5mcmVl ZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5m by9kcmktZGV2ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 From: heiko@sntech.de (Heiko Stuebner) Date: Mon, 19 Nov 2018 15:18:33 +0100 Subject: [PATCH] drm/rockchip: fix for mailbox read size In-Reply-To: <1541518625-25984-1-git-send-email-dkos@cadence.com> References: <1541518625-25984-1-git-send-email-dkos@cadence.com> Message-ID: <7088529.fTnRXqZmiP@phil> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Am Dienstag, 6. November 2018, 16:37:05 CET schrieb Damian Kos: > Some of the functions (like cdn_dp_dpcd_read, cdn_dp_get_edid_block) > allow to read 64KiB, but the cdn_dp_mailbox_read_receive, that is > used by them, can read only up to 255 bytes at once. Normally, it's > not a big issue as DPCD or EDID reads won't (hopefully) exceed that > value. > The real issue here is the revocation list read during the HDCP > authentication process. (problematic use case: > https://chromium.googlesource.com/chromiumos/third_party/kernel/+/chromeos-4.4/drivers/gpu/drm/rockchip/cdn-dp-reg.c#1152) > The list can reach 127*5+4 bytes (num devs * 5 bytes per ID/Bksv + > 4 bytes of an additional info). > In other words - CTSes with HDCP Repeater won't pass without this > fix. Oh, and the driver will most likely stop working (best case > scenario). > > Signed-off-by: Damian Kos applied to drm-misc-next Thanks Heiko 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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 72F37C43441 for ; Mon, 19 Nov 2018 14:18:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 45D3D20851 for ; Mon, 19 Nov 2018 14:18:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 45D3D20851 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=sntech.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729480AbeKTAma (ORCPT ); Mon, 19 Nov 2018 19:42:30 -0500 Received: from gloria.sntech.de ([185.11.138.130]:38384 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727324AbeKTAma (ORCPT ); Mon, 19 Nov 2018 19:42:30 -0500 Received: from we0660.dip.tu-dresden.de ([141.76.178.148] helo=phil.localnet) by gloria.sntech.de with esmtpsa (TLS1.0:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1gOkNm-0007v7-2B; Mon, 19 Nov 2018 15:18:34 +0100 From: Heiko Stuebner To: Damian Kos Cc: Chris Zhong , Sandy Huang , David Airlie , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] drm/rockchip: fix for mailbox read size Date: Mon, 19 Nov 2018 15:18:33 +0100 Message-ID: <7088529.fTnRXqZmiP@phil> In-Reply-To: <1541518625-25984-1-git-send-email-dkos@cadence.com> References: <1541518625-25984-1-git-send-email-dkos@cadence.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Dienstag, 6. November 2018, 16:37:05 CET schrieb Damian Kos: > Some of the functions (like cdn_dp_dpcd_read, cdn_dp_get_edid_block) > allow to read 64KiB, but the cdn_dp_mailbox_read_receive, that is > used by them, can read only up to 255 bytes at once. Normally, it's > not a big issue as DPCD or EDID reads won't (hopefully) exceed that > value. > The real issue here is the revocation list read during the HDCP > authentication process. (problematic use case: > https://chromium.googlesource.com/chromiumos/third_party/kernel/+/chromeos-4.4/drivers/gpu/drm/rockchip/cdn-dp-reg.c#1152) > The list can reach 127*5+4 bytes (num devs * 5 bytes per ID/Bksv + > 4 bytes of an additional info). > In other words - CTSes with HDCP Repeater won't pass without this > fix. Oh, and the driver will most likely stop working (best case > scenario). > > Signed-off-by: Damian Kos applied to drm-misc-next Thanks Heiko