From patchwork Thu Aug 27 16:39:14 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas Stach X-Patchwork-Id: 7086081 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id E80ACBEEC1 for ; Thu, 27 Aug 2015 16:43:28 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 150312094F for ; Thu, 27 Aug 2015 16:43:28 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2ED4420949 for ; Thu, 27 Aug 2015 16:43:27 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZV0EH-0003u8-FF; Thu, 27 Aug 2015 16:40:45 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZV0DL-000254-Eo for linux-arm-kernel@lists.infradead.org; Thu, 27 Aug 2015 16:39:49 +0000 Received: from dude.hi.4.pengutronix.de ([10.1.0.7] helo=dude.pengutronix.de.) by metis.ext.pengutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1ZV0Cx-00033b-6i; Thu, 27 Aug 2015 18:39:23 +0200 From: Lucas Stach To: Shawn Guo Subject: [PATCH 1/8] clk: imx: add common logic to detect early UART usage Date: Thu, 27 Aug 2015 18:39:14 +0200 Message-Id: <1440693561-28095-2-git-send-email-l.stach@pengutronix.de> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1440693561-28095-1-git-send-email-l.stach@pengutronix.de> References: <1440693561-28095-1-git-send-email-l.stach@pengutronix.de> X-SA-Exim-Connect-IP: 10.1.0.7 X-SA-Exim-Mail-From: l.stach@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150827_093947_769072_E80B1782 X-CRM114-Status: GOOD ( 10.43 ) X-Spam-Score: -3.3 (---) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michael Turquette , Stephen Boyd , patchwork-lst@pengutronix.de, kernel@pengutronix.de, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Both earlycon and eralyprintk depend on the bootloader setup UART clocks being retained. This patch adds the common logic to detect such situations and make the information available to the clock drivers, as well as adding the facilities to disable those clocks at the end of the kernel init. Signed-off-by: Lucas Stach --- drivers/clk/imx/clk.c | 33 +++++++++++++++++++++++++++++++++ drivers/clk/imx/clk.h | 2 ++ 2 files changed, 35 insertions(+) diff --git a/drivers/clk/imx/clk.c b/drivers/clk/imx/clk.c index df12b5307175..70580c8d1a3c 100644 --- a/drivers/clk/imx/clk.c +++ b/drivers/clk/imx/clk.c @@ -73,3 +73,36 @@ void imx_cscmr1_fixup(u32 *val) *val ^= CSCMR1_FIXUP; return; } + +static int __initdata imx_keep_uart_clocks; +static void __initdata (*imx_uart_disable_fn)(void); + +static int __init imx_keep_uart_clocks_param(char *str) +{ + imx_keep_uart_clocks = 1; + + return 0; +} +__setup_param("earlycon", imx_keep_uart_earlycon, + imx_keep_uart_clocks_param, 0); +__setup_param("earlyprintk", imx_keep_uart_earlyprintk, + imx_keep_uart_clocks_param, 0); + +int __init imx_clk_keep_uart(void) +{ + return imx_keep_uart_clocks; +} + +void __init imx_clk_set_uart_disable_callback(void (*disable_cb)(void)) +{ + imx_uart_disable_fn = disable_cb; +} + +static int __init imx_clk_disable_uart(void) +{ + if (imx_uart_disable_fn) + imx_uart_disable_fn(); + + return 0; +} +late_initcall_sync(imx_clk_disable_uart); diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h index 1049b0c7d818..41725a92c63c 100644 --- a/drivers/clk/imx/clk.h +++ b/drivers/clk/imx/clk.h @@ -7,6 +7,8 @@ extern spinlock_t imx_ccm_lock; void imx_check_clocks(struct clk *clks[], unsigned int count); +int imx_clk_keep_uart(void); +void imx_clk_set_uart_disable_callback(void (*disable_cb)(void)); extern void imx_cscmr1_fixup(u32 *val);