From patchwork Tue Jun 6 00:54:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Andreas_F=C3=A4rber?= X-Patchwork-Id: 9767829 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 485266034B for ; Tue, 6 Jun 2017 00:57:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3D41A27968 for ; Tue, 6 Jun 2017 00:57:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3151828435; Tue, 6 Jun 2017 00:57:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 7167627968 for ; Tue, 6 Jun 2017 00:57:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=+/0N4v7WjU4o6ZO+b14wv7O8dz61khVfEC//gGa2DxM=; b=g9UfMiro0j1Dqb VtovHUwiXmWcGUbrW5fT7Y6S2DM8QwleAzaWhdbDiCemvj9Ot7myUbPXyOEnpAS8/hvITVK/SeMKB B4Ex9nPNrd2suf/Xl0THz+Md3eJZL3gU7zFFq5rqtjSAZl1NTAs493GRCIQrWN/yQFgpEg0fUjUgf jS2AvDvqs+FrBDCHOrYK05+IfUCcg7hm8GlW4QYqUpDDzhg1kqvxn8s2xK7Pfdl6ulU0V1j9gdIRh Ujye7OkgKpzV7ywa50tC+EBkmmnG06JsDvlsvkTTFz2uzg3DiatAtR+UGQ5NSgfkDYMlQShFqGD0/ ark+2Hyt+avfubYvydVw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1dI2o0-0007qg-Rq; Tue, 06 Jun 2017 00:57:08 +0000 Received: from mx2.suse.de ([195.135.220.15] helo=mx1.suse.de) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1dI2ml-0005o2-4g for linux-arm-kernel@lists.infradead.org; Tue, 06 Jun 2017 00:56:00 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 8193CAD74; Tue, 6 Jun 2017 00:55:09 +0000 (UTC) From: =?UTF-8?q?Andreas=20F=C3=A4rber?= To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 09/28] tty: serial: Add Actions Semi Owl UART earlycon Date: Tue, 6 Jun 2017 02:54:07 +0200 Message-Id: <20170606005426.26446-10-afaerber@suse.de> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20170606005426.26446-1-afaerber@suse.de> References: <20170606005426.26446-1-afaerber@suse.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170605_175552_555668_255C8AC3 X-CRM114-Status: GOOD ( 19.13 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: support@lemaker.org, =?UTF-8?q?=E5=BC=A0=E5=A4=A9=E7=9B=8A?= , Greg Kroah-Hartman , 96boards@ucrobotics.com, linux-kernel@vger.kernel.org, Thomas Liau , mp-cs@actions-semi.com, linux-serial@vger.kernel.org, =?UTF-8?q?=E5=88=98=E7=82=9C?= , Jiri Slaby , =?UTF-8?q?Andreas=20F=C3=A4rber?= , =?UTF-8?q?=E5=BC=A0=E4=B8=9C=E9=A3=8E?= Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP This implements an earlycon for Actions Semi S500/S900 SoCs. Based on LeMaker linux-actions tree. Signed-off-by: Andreas Färber --- v3 -> v4: Unchanged v2 -> v3: * Adopted BIT() macro v1 -> v2: * Extended Kconfig help to mention earlycon (Arnd) * Spelled out Actions Semiconductor in Kconfig help * Adopted "actions" vendor prefix drivers/tty/serial/Kconfig | 19 ++++++ drivers/tty/serial/Makefile | 1 + drivers/tty/serial/owl-uart.c | 135 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 155 insertions(+) create mode 100644 drivers/tty/serial/owl-uart.c diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 5c8850f7a2a0..38f90ea45cf7 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -1688,6 +1688,25 @@ config SERIAL_MVEBU_CONSOLE and warnings and which allows logins in single user mode) Otherwise, say 'N'. +config SERIAL_OWL + bool "Actions Semi Owl serial port support" + depends on ARCH_ACTIONS || COMPILE_TEST + select SERIAL_CORE + help + This driver is for Actions Semiconductor S500/S900 SoC's UART. + Say 'Y' here if you wish to use the on-board serial port. + Otherwise, say 'N'. + +config SERIAL_OWL_CONSOLE + bool "Console on Actions Semi Owl serial port" + depends on SERIAL_OWL=y + select SERIAL_CORE_CONSOLE + select SERIAL_EARLYCON + default y + help + Say 'Y' here if you wish to use Actions Semiconductor S500/S900 UART + as the system console. Only earlycon is implemented currently. + endmenu config SERIAL_MCTRL_GPIO diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile index 53c03e005132..fe88a75d9a59 100644 --- a/drivers/tty/serial/Makefile +++ b/drivers/tty/serial/Makefile @@ -92,6 +92,7 @@ obj-$(CONFIG_SERIAL_STM32) += stm32-usart.o obj-$(CONFIG_SERIAL_MVEBU_UART) += mvebu-uart.o obj-$(CONFIG_SERIAL_PIC32) += pic32_uart.o obj-$(CONFIG_SERIAL_MPS2_UART) += mps2-uart.o +obj-$(CONFIG_SERIAL_OWL) += owl-uart.o # GPIOLIB helpers for modem control lines obj-$(CONFIG_SERIAL_MCTRL_GPIO) += serial_mctrl_gpio.o diff --git a/drivers/tty/serial/owl-uart.c b/drivers/tty/serial/owl-uart.c new file mode 100644 index 000000000000..1b8008797a1b --- /dev/null +++ b/drivers/tty/serial/owl-uart.c @@ -0,0 +1,135 @@ +/* + * Actions Semi Owl family serial console + * + * Copyright 2013 Actions Semi Inc. + * Author: Actions Semi, Inc. + * + * Copyright (c) 2016-2017 Andreas Färber + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define OWL_UART_CTL 0x000 +#define OWL_UART_TXDAT 0x008 +#define OWL_UART_STAT 0x00c + +#define OWL_UART_CTL_TRFS_TX BIT(14) +#define OWL_UART_CTL_EN BIT(15) +#define OWL_UART_CTL_RXIE BIT(18) +#define OWL_UART_CTL_TXIE BIT(19) + +#define OWL_UART_STAT_RIP BIT(0) +#define OWL_UART_STAT_TIP BIT(1) +#define OWL_UART_STAT_TFFU BIT(6) +#define OWL_UART_STAT_TRFL_MASK (0x1f << 11) +#define OWL_UART_STAT_UTBB BIT(17) + +static inline void owl_uart_write(struct uart_port *port, u32 val, unsigned int off) +{ + writel(val, port->membase + off); +} + +static inline u32 owl_uart_read(struct uart_port *port, unsigned int off) +{ + return readl(port->membase + off); +} + +#ifdef CONFIG_SERIAL_OWL_CONSOLE + +static void owl_console_putchar(struct uart_port *port, int ch) +{ + if (!port->membase) + return; + + while (owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_TFFU) + cpu_relax(); + + owl_uart_write(port, ch, OWL_UART_TXDAT); +} + +static void owl_uart_port_write(struct uart_port *port, const char *s, + u_int count) +{ + u32 old_ctl, val; + unsigned long flags; + int locked; + + local_irq_save(flags); + + if (port->sysrq) + locked = 0; + else if (oops_in_progress) + locked = spin_trylock(&port->lock); + else { + spin_lock(&port->lock); + locked = 1; + } + + old_ctl = owl_uart_read(port, OWL_UART_CTL); + val = old_ctl | OWL_UART_CTL_TRFS_TX; + /* disable IRQ */ + val &= ~(OWL_UART_CTL_RXIE | OWL_UART_CTL_TXIE); + owl_uart_write(port, val, OWL_UART_CTL); + + uart_console_write(port, s, count, owl_console_putchar); + + /* wait until all contents have been sent out */ + while (owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_TRFL_MASK) + cpu_relax(); + + /* clear IRQ pending */ + val = owl_uart_read(port, OWL_UART_STAT); + val |= OWL_UART_STAT_TIP | OWL_UART_STAT_RIP; + owl_uart_write(port, val, OWL_UART_STAT); + + owl_uart_write(port, old_ctl, OWL_UART_CTL); + + if (locked) + spin_unlock(&port->lock); + + local_irq_restore(flags); +} + +static void owl_uart_early_console_write(struct console *co, + const char *s, + u_int count) +{ + struct earlycon_device *dev = co->data; + + owl_uart_port_write(&dev->port, s, count); +} + +static int __init +owl_uart_early_console_setup(struct earlycon_device *device, const char *opt) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = owl_uart_early_console_write; + + return 0; +} +OF_EARLYCON_DECLARE(owl, "actions,owl-uart", + owl_uart_early_console_setup); + +#endif /* CONFIG_SERIAL_OWL_CONSOLE */