From mboxrd@z Thu Jan 1 00:00:00 1970 From: Todd Previte Subject: Re: [PATCH 1/2] drm/i915: Do a dummy DPCD read before the actual read Date: Thu, 16 Oct 2014 12:39:29 -0700 Message-ID: <54401EF1.4060908@gmail.com> References: <1413481570-18288-1-git-send-email-ville.syrjala@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; Format="flowed" Content-Transfer-Encoding: base64 Return-path: Received: from mail-pa0-f46.google.com (mail-pa0-f46.google.com [209.85.220.46]) by gabe.freedesktop.org (Postfix) with ESMTP id 352816E02C for ; Thu, 16 Oct 2014 12:39:27 -0700 (PDT) Received: by mail-pa0-f46.google.com with SMTP id fa1so4033515pad.33 for ; Thu, 16 Oct 2014 12:39:27 -0700 (PDT) Received: from [192.168.1.212] (ip72-201-95-47.ph.ph.cox.net. [72.201.95.47]) by mx.google.com with ESMTPSA id xj9sm20638213pab.40.2014.10.16.12.39.26 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 Oct 2014 12:39:26 -0700 (PDT) In-Reply-To: <1413481570-18288-1-git-send-email-ville.syrjala@linux.intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org Ck9uIDEwLzE2LzIwMTQgMTA6NDYgQU0sIHZpbGxlLnN5cmphbGFAbGludXguaW50ZWwuY29tIHdy b3RlOgo+IEZyb206IFZpbGxlIFN5cmrDpGzDpCA8dmlsbGUuc3lyamFsYUBsaW51eC5pbnRlbC5j b20+Cj4KPiBTb21ldGltZXMgd2Ugc2VlbSB0byBnZXQgdXR0ZXIgZ2FyYmFnZSBmcm9tIERQQ0Qg cmVhZHMuIFRoZSByZXN1bHRpbmcKPiBidWZmZXIgaXMgZmlsbGVkIHdpdGggdGhlIHNhbWUgYnl0 ZSwgYW5kIHRoZSBvcGVyYXRpb24gY29tcGxldGVkIHdpdGhvdXQKPiBlcnJvcnMuIE15IEhQIFpS MjR3IG1vbml0b3Igc2VlbXMgcGFydGljdWxhcmx5IHN1c2NlcHRpYmxlIHRvIHRoaXMKPiBwcm9i bGVtIG9uY2UgaXQncyBnb25lIGludG8gYSBzbGVlcCBtb2RlLgo+Cj4gVGhlIGlzc3VlIHNlZW1z IHRvIGhhcHBlbiBvbmx5IGZvciB0aGUgZmlyc3QgQVVYIG1lc3NhZ2UgdGhhdCB3YWtlcyB0aGUK PiBzaW5rIHVwLiBCdXQgYXMgdGhlIGZpcnN0IEFVWCByZWFkIHdlIG9mdGVuIGRvIGlzIHRoZSBE UENEIHJlY2VpdmVyCj4gY2FwIGl0IGRvZXMgd3JlYWsgYSBiaXQgb2YgaGF2b2Mgd2l0aCBzdWJz ZXF1ZW50IGxpbmsgdHJhaW5pbmcgZXRjLiB3aGVuCj4gdGhlIHJlY2VpdmVyIGNhcCBidy9sYW5l L2V0Yy4gaW5mb3JtYXRpb24gaXMgZ2FyYmFnZS4KPgo+IEEgc3VmZmljaWVudCB3b3JrYXJvdW5k IHNlZW1zIHRvIGJlIHRvIHBlcmZvcm0gYSBzaW5nbGUgYnl0ZSBkdW1teSByZWFkCj4gYmVmb3Jl IHJlYWRpbmcgdGhlIGFjdHVhbCBkYXRhLiBJIHN1cHBvc2UgdGhhdCBqdXN0IHdha2VzIHVwIHRo ZSBzaW5rCj4gc3VmZmljaWVudGx5IGFuZCB3ZSBjYW4ganVzdCB0aHJvdyBhd2F5IHRoZSByZXR1 cm5lZCBkYXRhIGluIGNhc2UgaXQncwo+IGNyYXAuIERQX0RQQ0RfUkVWIHNlZW1zIGxpa2UgYSBz dWZmaWNpZW50bHkgc2FmZSBsb2NhdGlvbiB0byByZWFkIGhlcmUuCj4KPiBTaWduZWQtb2ZmLWJ5 OiBWaWxsZSBTeXJqw6Rsw6QgPHZpbGxlLnN5cmphbGFAbGludXguaW50ZWwuY29tPgo+IC0tLQo+ ICAgZHJpdmVycy9ncHUvZHJtL2k5MTUvaW50ZWxfZHAuYyB8IDcgKysrKysrKwo+ICAgMSBmaWxl IGNoYW5nZWQsIDcgaW5zZXJ0aW9ucygrKQo+Cj4gZGlmZiAtLWdpdCBhL2RyaXZlcnMvZ3B1L2Ry bS9pOTE1L2ludGVsX2RwLmMgYi9kcml2ZXJzL2dwdS9kcm0vaTkxNS9pbnRlbF9kcC5jCj4gaW5k ZXggNjRjOGUwNC4uZjA3ZjAyYyAxMDA2NDQKPiAtLS0gYS9kcml2ZXJzL2dwdS9kcm0vaTkxNS9p bnRlbF9kcC5jCj4gKysrIGIvZHJpdmVycy9ncHUvZHJtL2k5MTUvaW50ZWxfZHAuYwo+IEBAIC0y ODcwLDYgKzI4NzAsMTMgQEAgaW50ZWxfZHBfZHBjZF9yZWFkX3dha2Uoc3RydWN0IGRybV9kcF9h dXggKmF1eCwgdW5zaWduZWQgaW50IG9mZnNldCwKPiAgIAlzc2l6ZV90IHJldDsKPiAgIAlpbnQg aTsKPiAgIAo+ICsJLyoKPiArCSAqIFNvbWV0aW1lIHdlIGp1c3QgZ2V0IHRoZSBzYW1lIGluY29y cmVjdCBieXRlIHJlcGVhdGVkCj4gKwkgKiBvdmVyIHRoZSBlbnRpcmUgYnVmZmVyLiBEb2luZyBq dXN0IG9uZSB0aHJvdyBhd2F5IHJlYWQKPiArCSAqIGluaXRpYWxseSBzZWVtcyB0byAic29sdmUi IGl0Lgo+ICsJICovCj4gKwlkcm1fZHBfZHBjZF9yZWFkKGF1eCwgRFBfRFBDRF9SRVYsIGJ1ZmZl ciwgMSk7Cj4gKwo+ICAgCWZvciAoaSA9IDA7IGkgPCAzOyBpKyspIHsKPiAgIAkJcmV0ID0gZHJt X2RwX2RwY2RfcmVhZChhdXgsIG9mZnNldCwgYnVmZmVyLCBzaXplKTsKPiAgIAkJaWYgKHJldCA9 PSBzaXplKQpTZWVtcyBsaWtlIGEgcmVhc29uYWJsZSB3b3JrYXJvdW5kIGZvciB0aGlzIHByb2Js ZW0sIHRob3VnaCAKaW52ZXN0aWdhdGluZyB0aGUgYWN0dWFsIHJvb3QgY2F1c2UgbWlnaHQgYmUg d29ydGh3aGlsZS4KClJldmlld2VkLWJ5OiBUb2RkIFByZXZpdGUgPHRwcmV2aXRlQGdtYWlsLmNv bT4KX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KSW50ZWwt Z2Z4IG1haWxpbmcgbGlzdApJbnRlbC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHA6Ly9s aXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9pbnRlbC1nZngK