From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932252AbbGCP3J (ORCPT ); Fri, 3 Jul 2015 11:29:09 -0400 Received: from mail-wg0-f49.google.com ([74.125.82.49]:36221 "EHLO mail-wg0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932169AbbGCP3B (ORCPT ); Fri, 3 Jul 2015 11:29:01 -0400 From: David Dueck To: linux-kernel@vger.kernel.org Cc: bigeasy@linutronix.de, nicolas.ferre@atmel.com, alexandre.belloni@free-electrons.com, ludovic.desroches@atmel.com, boris.brezillon@free-electrons.com, maxime.ripard@free-electrons.com, wsteinwender@pcs.com, antoine.tenart@free-electrons.com, mail@jann.io, c.emde@osadl.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH RFC 0/2] RT-Preempt on SAMA5 Date: Fri, 3 Jul 2015 17:28:41 +0200 Message-Id: <1435937323-16913-1-git-send-email-davidcdueck@googlemail.com> X-Mailer: git-send-email 2.4.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org RT-Preempt crashes early at boot on SAMA5. The reason is that drivers/clk/at91/* is using interrupts very early, before kthreadd is up. Just making those IRQF_NOTHREAD is not an option as the handlers are taking spin locks. Perhaps we can have some discussion on how to go on with this. Is there some problem if we just do not use interrupts here anymore? (at least for the clocks that are needed very early) The patches are on top of the RT patches for 4.0. The second patch might not be needed if we just drop the RT patch that touches the PIT code. David Dueck (2): at91: make using irqs for clock handling optional at91: use request_irq/free_irq instead of setup_irq/remove_irq drivers/clk/Kconfig | 1 + drivers/clk/at91/Kconfig | 4 ++ drivers/clk/at91/clk-main.c | 34 ++++++++++++++++ drivers/clk/at91/clk-master.c | 11 +++++ drivers/clk/at91/clk-pll.c | 11 ++++- drivers/clk/at91/clk-system.c | 11 +++++ drivers/clk/at91/clk-utmi.c | 10 +++++ drivers/clk/at91/pmc.c | 6 +++ drivers/clocksource/timer-atmel-pit.c | 76 ++++++++++++++++++----------------- 9 files changed, 127 insertions(+), 37 deletions(-) create mode 100644 drivers/clk/at91/Kconfig -- 2.4.4