From patchwork Tue Jun 27 00:55:19 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: 9810657 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 193BB603D7 for ; Tue, 27 Jun 2017 00:58:42 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7D6C027861 for ; Tue, 27 Jun 2017 00:58:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 71BDB283A5; Tue, 27 Jun 2017 00:58:38 +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 B9ED327861 for ; Tue, 27 Jun 2017 00:58:37 +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=kjdOMZx+15+VvgMTpS29IRVWsy5W/khoa+Ux0gbbxww=; b=DHHIGtKaWdzSEz 4wXA0pe3OY20MPeyLhT+mcDFWqiuMI33PJunR7LtKhVEkioFMwfNOIc1LgjJ1hOoyHtgCPMN4a2Jq XUhYmEzUH/0oKIDBwDT5pFEG7VEv/ci0LpqCMQfLXLngl3euHOlDi42TL2eOmgU7QDfGF8qPMxIAM IbKFRHWEdv1iscIpo/JyqHksAt2pccK1f1K+U/74UdXbnWnSXKHU2mQlljGinHMSl0SH3tyk1yISQ 5H3Z4cgw9BOkOL4vhvenczY5z4eaJfbCLVjpoPWl/qxdZxh+Nu1obq0lrxgllsSDObcfTW211pH01 qU5oq30rC15h4U0pg5Og==; 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 1dPepu-0000Ht-Fr; Tue, 27 Jun 2017 00:58:34 +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 1dPeom-00071U-69 for linux-arm-kernel@lists.infradead.org; Tue, 27 Jun 2017 00:57:28 +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 6DD5BAC14; Tue, 27 Jun 2017 00:56:38 +0000 (UTC) From: =?UTF-8?q?Andreas=20F=C3=A4rber?= To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 5/6] tty: serial: Add RDA Micro UART driver Date: Tue, 27 Jun 2017 02:55:19 +0200 Message-Id: <20170627005520.23731-6-afaerber@suse.de> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20170627005520.23731-1-afaerber@suse.de> References: <20170627005520.23731-1-afaerber@suse.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170626_175724_890672_81C78B29 X-CRM114-Status: GOOD ( 19.82 ) 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: Jonathan Corbet , Greg Kroah-Hartman , service@rdamicro.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Jiri Slaby , =?UTF-8?q?Andreas=20F=C3=A4rber?= , zhao_steven@263.net 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 Add "rda" earlycon driver for RDA8810PL UART. Signed-off-by: Andreas Färber --- Documentation/admin-guide/kernel-parameters.txt | 6 ++ drivers/tty/serial/Kconfig | 19 ++++ drivers/tty/serial/Makefile | 1 + drivers/tty/serial/rda-uart.c | 117 ++++++++++++++++++++++++ 4 files changed, 143 insertions(+) create mode 100644 drivers/tty/serial/rda-uart.c diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 0e2091c6fa6b..c97f8b64b3f1 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -967,6 +967,12 @@ specified address. The serial port must already be setup and configured. Options are not yet supported. + rda, + Start an early, polled-mode console on a serial port + of an RDA Micro SoC, such as RDA8810PL, at the + specified address. The serial port must already be + setup and configured. Options are not yet supported. + smh Use ARM semihosting calls for early console. s3c2410, diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 1f096e2bb398..25e106a62e06 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -1707,6 +1707,25 @@ config SERIAL_OWL_CONSOLE Say 'Y' here if you wish to use Actions Semiconductor S500/S900 UART as the system console. Only earlycon is implemented currently. +config SERIAL_RDA + bool "RDA Micro serial port support" + depends on ARCH_RDA || COMPILE_TEST + select SERIAL_CORE + help + This driver is for RDA8810PL SoC's UART. + Say 'Y' here if you wish to use the on-board serial port. + Otherwise, say 'N'. + +config SERIAL_RDA_CONSOLE + bool "Console on RDA Micro serial port" + depends on SERIAL_RDA=y + select SERIAL_CORE_CONSOLE + select SERIAL_EARLYCON + default y + help + Say 'Y' here if you wish to use the RDA8810PL 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 fe88a75d9a59..87f5a6e1e2d4 100644 --- a/drivers/tty/serial/Makefile +++ b/drivers/tty/serial/Makefile @@ -93,6 +93,7 @@ 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 +obj-$(CONFIG_SERIAL_RDA) += rda-uart.o # GPIOLIB helpers for modem control lines obj-$(CONFIG_SERIAL_MCTRL_GPIO) += serial_mctrl_gpio.o diff --git a/drivers/tty/serial/rda-uart.c b/drivers/tty/serial/rda-uart.c new file mode 100644 index 000000000000..c3c9cf1df015 --- /dev/null +++ b/drivers/tty/serial/rda-uart.c @@ -0,0 +1,117 @@ +/* + * RDA8810PL serial console + * + * Copyright RDA Microelectronics Company Limited + * Copyright (c) 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 RDA_UART_CTRL 0x00 +#define RDA_UART_STATUS 0x04 +#define RDA_UART_RXTX_BUFFER 0x08 +#define RDA_UART_IRQ_MASK 0x0c + +#define RDA_UART_STATUS_TX_FIFO_SPACE_MASK (0x1f << 8) + +static inline void rda_uart_write(struct uart_port *port, u32 val, unsigned int off) +{ + writel(val, port->membase + off); +} + +static inline u32 rda_uart_read(struct uart_port *port, unsigned int off) +{ + return readl(port->membase + off); +} + +#ifdef CONFIG_SERIAL_RDA_CONSOLE + +static void rda_console_putchar(struct uart_port *port, int ch) +{ + if (!port->membase) + return; + + while (!(rda_uart_read(port, RDA_UART_STATUS) & RDA_UART_STATUS_TX_FIFO_SPACE_MASK)) + cpu_relax(); + + rda_uart_write(port, ch, RDA_UART_RXTX_BUFFER); +} + +static void rda_uart_port_write(struct uart_port *port, const char *s, + u_int count) +{ + u32 old_irq_mask; + 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_irq_mask = rda_uart_read(port, RDA_UART_IRQ_MASK); + rda_uart_write(port, 0, RDA_UART_IRQ_MASK); + + uart_console_write(port, s, count, rda_console_putchar); + + /* wait until all contents have been sent out */ + while (!(rda_uart_read(port, RDA_UART_STATUS) & RDA_UART_STATUS_TX_FIFO_SPACE_MASK)) + cpu_relax(); + + rda_uart_write(port, old_irq_mask, RDA_UART_IRQ_MASK); + + if (locked) + spin_unlock(&port->lock); + + local_irq_restore(flags); +} + +static void rda_uart_early_console_write(struct console *co, + const char *s, + u_int count) +{ + struct earlycon_device *dev = co->data; + + rda_uart_port_write(&dev->port, s, count); +} + +static int __init +rda_uart_early_console_setup(struct earlycon_device *device, const char *opt) +{ + if (!device->port.membase) + return -ENODEV; + + device->con->write = rda_uart_early_console_write; + + return 0; +} +OF_EARLYCON_DECLARE(rda, "rda,8810pl-uart", + rda_uart_early_console_setup); + +#endif /* CONFIG_SERIAL_RDA_CONSOLE */