From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH 0/3] Use Tegra's microsecond counter for udelay() Date: Mon, 16 Jun 2014 12:52:10 -0600 Message-ID: <539F3CDA.407@wwwdotorg.org> References: <1402588713-18766-1-git-send-email-pdeschrijver@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1402588713-18766-1-git-send-email-pdeschrijver-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Peter De Schrijver Cc: Russell King , Daniel Lezcano , Thomas Gleixner , Thierry Reding , Paul Gortmaker , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-tegra@vger.kernel.org On 06/12/2014 09:58 AM, Peter De Schrijver wrote: > This patchset introduces support for Tegra's microsecond counter as the > udelay() timer. This is useful on Tegra SoCs which do not have an arch timer > such as Tegra20 and Tegra30. Using the microsecond counter instead of a delay > based loop avoids potential problems during cpu frequency changes. > > The set consists of 3 patches: > > Patch 1 introduces a new call which is used by the ARM architecture delay > timer code to prevent changing the delay timer after calibration is finished > and thus can be in use. > > Patch 2 adds logic to choose the delay timer with the highest resolution. This > allows the same registration code to be used on all Tegra SoCs and yet use the > higher resolution arch timer when available (eg on Tegra114 or Tegra124). > > Patch 3 adds the actual delay timer code. > > Patch set has been verified on ventana (Tegra20), beaver (Tegra30), > dalmore (Tegra114) and jetson TK1 (Tegra124). I've applied this series to Tegra's for-3.17/delay-timer branch. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932232AbaFPSwP (ORCPT ); Mon, 16 Jun 2014 14:52:15 -0400 Received: from avon.wwwdotorg.org ([70.85.31.133]:38864 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755565AbaFPSwN (ORCPT ); Mon, 16 Jun 2014 14:52:13 -0400 Message-ID: <539F3CDA.407@wwwdotorg.org> Date: Mon, 16 Jun 2014 12:52:10 -0600 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Peter De Schrijver CC: Russell King , Daniel Lezcano , Thomas Gleixner , Thierry Reding , Paul Gortmaker , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-tegra@vger.kernel.org Subject: Re: [PATCH 0/3] Use Tegra's microsecond counter for udelay() References: <1402588713-18766-1-git-send-email-pdeschrijver@nvidia.com> In-Reply-To: <1402588713-18766-1-git-send-email-pdeschrijver@nvidia.com> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/12/2014 09:58 AM, Peter De Schrijver wrote: > This patchset introduces support for Tegra's microsecond counter as the > udelay() timer. This is useful on Tegra SoCs which do not have an arch timer > such as Tegra20 and Tegra30. Using the microsecond counter instead of a delay > based loop avoids potential problems during cpu frequency changes. > > The set consists of 3 patches: > > Patch 1 introduces a new call which is used by the ARM architecture delay > timer code to prevent changing the delay timer after calibration is finished > and thus can be in use. > > Patch 2 adds logic to choose the delay timer with the highest resolution. This > allows the same registration code to be used on all Tegra SoCs and yet use the > higher resolution arch timer when available (eg on Tegra114 or Tegra124). > > Patch 3 adds the actual delay timer code. > > Patch set has been verified on ventana (Tegra20), beaver (Tegra30), > dalmore (Tegra114) and jetson TK1 (Tegra124). I've applied this series to Tegra's for-3.17/delay-timer branch. From mboxrd@z Thu Jan 1 00:00:00 1970 From: swarren@wwwdotorg.org (Stephen Warren) Date: Mon, 16 Jun 2014 12:52:10 -0600 Subject: [PATCH 0/3] Use Tegra's microsecond counter for udelay() In-Reply-To: <1402588713-18766-1-git-send-email-pdeschrijver@nvidia.com> References: <1402588713-18766-1-git-send-email-pdeschrijver@nvidia.com> Message-ID: <539F3CDA.407@wwwdotorg.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 06/12/2014 09:58 AM, Peter De Schrijver wrote: > This patchset introduces support for Tegra's microsecond counter as the > udelay() timer. This is useful on Tegra SoCs which do not have an arch timer > such as Tegra20 and Tegra30. Using the microsecond counter instead of a delay > based loop avoids potential problems during cpu frequency changes. > > The set consists of 3 patches: > > Patch 1 introduces a new call which is used by the ARM architecture delay > timer code to prevent changing the delay timer after calibration is finished > and thus can be in use. > > Patch 2 adds logic to choose the delay timer with the highest resolution. This > allows the same registration code to be used on all Tegra SoCs and yet use the > higher resolution arch timer when available (eg on Tegra114 or Tegra124). > > Patch 3 adds the actual delay timer code. > > Patch set has been verified on ventana (Tegra20), beaver (Tegra30), > dalmore (Tegra114) and jetson TK1 (Tegra124). I've applied this series to Tegra's for-3.17/delay-timer branch.