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From: "Peng Fan (OSS)" To: sstabellini@kernel.org, julien@xen.org, Volodymyr_Babchuk@epam.com, bertrand.marquis@arm.com Cc: andrew.cooper3@citrix.com, george.dunlap@citrix.com, jbeulich@suse.com, wl@xen.org, xen-devel@lists.xenproject.org, van.freenix@gmail.com, michal.orzel@arm.com, Peng Fan , Henry Wang Subject: [PATCH V4 1/2] xen/arm: Add i.MX lpuart driver Date: Fri, 8 Apr 2022 22:09:31 +0800 Message-Id: <20220408140932.17968-2-peng.fan@oss.nxp.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220408140932.17968-1-peng.fan@oss.nxp.com> References: <20220408140932.17968-1-peng.fan@oss.nxp.com> X-ClientProxiedBy: SI2PR06CA0001.apcprd06.prod.outlook.com (2603:1096:4:186::21) To DU0PR04MB9417.eurprd04.prod.outlook.com (2603:10a6:10:358::11) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: bb64134a-cf59-4f5e-06f8-08da1963ac08 X-MS-TrafficTypeDiagnostic: AM7PR04MB6949:EE_ X-MS-Exchange-SharedMailbox-RoutingAgent-Processed: True X-Microsoft-Antispam-PRVS: X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-OriginatorOrg: oss.nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: bb64134a-cf59-4f5e-06f8-08da1963ac08 X-MS-Exchange-CrossTenant-AuthSource: DU0PR04MB9417.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Apr 2022 13:28:30.7978 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Fkqgfz2OF5Q5Wl84rqL47bR1xdJaFlbX8CVdo/HShVrv7yxQ1AUlHnhaLPtk8E1x0sSaVTlnt+lBKWOFmnzF5Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM7PR04MB6949 From: Peng Fan The i.MX LPUART Documentation: https://www.nxp.com/webapp/Download?colCode=IMX8QMIEC Chatper 13.6 Low Power Universal Asynchronous Receiver/ Transmitter (LPUART) Tested-by: Henry Wang Signed-off-by: Peng Fan --- xen/arch/arm/include/asm/imx-lpuart.h | 64 ++++++ xen/drivers/char/Kconfig | 7 + xen/drivers/char/Makefile | 1 + xen/drivers/char/imx-lpuart.c | 276 ++++++++++++++++++++++++++ 4 files changed, 348 insertions(+) create mode 100644 xen/arch/arm/include/asm/imx-lpuart.h create mode 100644 xen/drivers/char/imx-lpuart.c diff --git a/xen/arch/arm/include/asm/imx-lpuart.h b/xen/arch/arm/include/asm/imx-lpuart.h new file mode 100644 index 0000000000..26e2cf0249 --- /dev/null +++ b/xen/arch/arm/include/asm/imx-lpuart.h @@ -0,0 +1,64 @@ +/* + * xen/arch/arm/include/asm/imx-lpuart.h + * + * Common constant definition between early printk and the LPUART driver + * + * Peng Fan + * Copyright 2022 NXP + * + * 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. + */ + +#ifndef __ASM_ARM_IMX_LPUART_H__ +#define __ASM_ARM_IMX_LPUART_H__ + +/* 32-bit register definition */ +#define UARTBAUD (0x10) +#define UARTSTAT (0x14) +#define UARTCTRL (0x18) +#define UARTDATA (0x1C) +#define UARTMATCH (0x20) +#define UARTMODIR (0x24) +#define UARTFIFO (0x28) +#define UARTWATER (0x2c) + +#define UARTSTAT_TDRE BIT(23, UL) +#define UARTSTAT_TC BIT(22, UL) +#define UARTSTAT_RDRF BIT(21, UL) +#define UARTSTAT_OR BIT(19, UL) + +#define UARTBAUD_OSR_SHIFT (24) +#define UARTBAUD_OSR_MASK (0x1f) +#define UARTBAUD_SBR_MASK (0x1fff) +#define UARTBAUD_BOTHEDGE (0x00020000) +#define UARTBAUD_TDMAE (0x00800000) +#define UARTBAUD_RDMAE (0x00200000) + +#define UARTCTRL_TIE BIT(23, UL) +#define UARTCTRL_TCIE BIT(22, UL) +#define UARTCTRL_RIE BIT(21, UL) +#define UARTCTRL_ILIE BIT(20, UL) +#define UARTCTRL_TE BIT(19, UL) +#define UARTCTRL_RE BIT(18, UL) +#define UARTCTRL_M BIT(4, UL) + +#define UARTWATER_RXCNT_OFF 24 + +#endif /* __ASM_ARM_IMX_LPUART_H__ */ + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * indent-tabs-mode: nil + * End: + */ diff --git a/xen/drivers/char/Kconfig b/xen/drivers/char/Kconfig index 2ff5b288e2..e5f7b1d8eb 100644 --- a/xen/drivers/char/Kconfig +++ b/xen/drivers/char/Kconfig @@ -13,6 +13,13 @@ config HAS_CADENCE_UART This selects the Xilinx Zynq Cadence UART. If you have a Xilinx Zynq based board, say Y. +config HAS_IMX_LPUART + bool "i.MX LPUART driver" + default y + depends on ARM_64 + help + This selects the i.MX LPUART. If you have i.MX8QM based board, say Y. + config HAS_MVEBU bool "Marvell MVEBU UART driver" default y diff --git a/xen/drivers/char/Makefile b/xen/drivers/char/Makefile index 7c646d771c..14e67cf072 100644 --- a/xen/drivers/char/Makefile +++ b/xen/drivers/char/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_HAS_MVEBU) += mvebu-uart.o obj-$(CONFIG_HAS_OMAP) += omap-uart.o obj-$(CONFIG_HAS_SCIF) += scif-uart.o obj-$(CONFIG_HAS_EHCI) += ehci-dbgp.o +obj-$(CONFIG_HAS_IMX_LPUART) += imx-lpuart.o obj-$(CONFIG_ARM) += arm-uart.o obj-y += serial.o obj-$(CONFIG_XEN_GUEST) += xen_pv_console.o diff --git a/xen/drivers/char/imx-lpuart.c b/xen/drivers/char/imx-lpuart.c new file mode 100644 index 0000000000..df44f91e5d --- /dev/null +++ b/xen/drivers/char/imx-lpuart.c @@ -0,0 +1,276 @@ +/* + * xen/drivers/char/imx-lpuart.c + * + * Driver for i.MX LPUART. + * + * Peng Fan + * Copyright 2022 NXP + * + * 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. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define imx_lpuart_read(uart, off) readl((uart)->regs + off) +#define imx_lpuart_write(uart, off, val) writel((val), (uart)->regs + off) + +static struct imx_lpuart { + uint32_t baud, clock_hz, data_bits, parity, stop_bits, fifo_size; + uint32_t irq; + char __iomem *regs; + struct irqaction irqaction; + struct vuart_info vuart; +} imx8_com; + +static void imx_lpuart_interrupt(int irq, void *data, + struct cpu_user_regs *regs) +{ + struct serial_port *port = data; + struct imx_lpuart *uart = port->uart; + uint32_t sts, rxcnt; + + sts = imx_lpuart_read(uart, UARTSTAT); + rxcnt = imx_lpuart_read(uart, UARTWATER) >> UARTWATER_RXCNT_OFF; + + if ( (sts & UARTSTAT_RDRF) || (rxcnt > 0) ) + serial_rx_interrupt(port, regs); + + if ( sts & UARTSTAT_TDRE ) + serial_tx_interrupt(port, regs); + + imx_lpuart_write(uart, UARTSTAT, sts); +} + +static void __init imx_lpuart_init_preirq(struct serial_port *port) +{ + struct imx_lpuart *uart = port->uart; + uint32_t ctrl, old_ctrl, bd; + + old_ctrl = imx_lpuart_read(uart, UARTCTRL); + ctrl = (old_ctrl & ~UARTCTRL_M) | UARTCTRL_TE | UARTCTRL_RE; + bd = imx_lpuart_read(uart, UARTBAUD); + + while ( !(imx_lpuart_read(uart, UARTSTAT) & UARTSTAT_TC) ) + cpu_relax(); + + /* Disable transmit and receive */ + imx_lpuart_write(uart, UARTCTRL, old_ctrl & ~(UARTCTRL_TE | UARTCTRL_RE)); + + /* Reuse firmware baudrate settings, only disable DMA here */ + bd &= ~(UARTBAUD_TDMAE | UARTBAUD_RDMAE); + + imx_lpuart_write(uart, UARTMODIR, 0); + imx_lpuart_write(uart, UARTBAUD, bd); + imx_lpuart_write(uart, UARTCTRL, ctrl); +} + +static void __init imx_lpuart_init_postirq(struct serial_port *port) +{ + struct imx_lpuart *uart = port->uart; + uint32_t temp; + + uart->irqaction.handler = imx_lpuart_interrupt; + uart->irqaction.name = "imx_lpuart"; + uart->irqaction.dev_id = port; + + if ( setup_irq(uart->irq, 0, &uart->irqaction) != 0 ) + { + dprintk(XENLOG_ERR, "Failed to allocate imx_lpuart IRQ %d\n", + uart->irq); + return; + } + + /* Enable interrupts */ + temp = imx_lpuart_read(uart, UARTCTRL); + temp |= (UARTCTRL_RIE | UARTCTRL_TIE); + temp |= UARTCTRL_ILIE; + imx_lpuart_write(uart, UARTCTRL, temp); +} + +static void imx_lpuart_suspend(struct serial_port *port) +{ + BUG(); +} + +static void imx_lpuart_resume(struct serial_port *port) +{ + BUG(); +} + +static int imx_lpuart_tx_ready(struct serial_port *port) +{ + struct imx_lpuart *uart = port->uart; + + return imx_lpuart_read(uart, UARTSTAT) & UARTSTAT_TC; +} + +static void imx_lpuart_putc(struct serial_port *port, char c) +{ + struct imx_lpuart *uart = port->uart; + + while ( !(imx_lpuart_read(uart, UARTSTAT) & UARTSTAT_TDRE) ) + cpu_relax(); + + imx_lpuart_write(uart, UARTDATA, c); +} + +static int imx_lpuart_getc(struct serial_port *port, char *pc) +{ + struct imx_lpuart *uart = port->uart; + int ch; + + while ( !(imx_lpuart_read(uart, UARTSTAT) & UARTSTAT_RDRF) ) + return 0; + + ch = imx_lpuart_read(uart, UARTDATA); + *pc = ch & 0xff; + + if ( imx_lpuart_read(uart, UARTSTAT) & UARTSTAT_OR ) + imx_lpuart_write(uart, UARTSTAT, UARTSTAT_OR); + + return 1; +} + +static int __init imx_lpuart_irq(struct serial_port *port) +{ + struct imx_lpuart *uart = port->uart; + + return ((uart->irq > 0) ? uart->irq : -1); +} + +static const struct vuart_info *imx_lpuart_vuart_info(struct serial_port *port) +{ + struct imx_lpuart *uart = port->uart; + + return &uart->vuart; +} + +static void imx_lpuart_start_tx(struct serial_port *port) +{ + struct imx_lpuart *uart = port->uart; + uint32_t temp; + + temp = imx_lpuart_read(uart, UARTSTAT); + /* Wait until empty */ + while ( !(temp & UARTSTAT_TDRE) ) + cpu_relax(); + + temp = imx_lpuart_read(uart, UARTCTRL); + imx_lpuart_write(uart, UARTCTRL, (temp | UARTCTRL_TIE)); +} + +static void imx_lpuart_stop_tx(struct serial_port *port) +{ + struct imx_lpuart *uart = port->uart; + uint32_t temp; + + temp = imx_lpuart_read(uart, UARTCTRL); + temp &= ~(UARTCTRL_TIE | UARTCTRL_TCIE); + imx_lpuart_write(uart, UARTCTRL, temp); +} + +static struct uart_driver __read_mostly imx_lpuart_driver = { + .init_preirq = imx_lpuart_init_preirq, + .init_postirq = imx_lpuart_init_postirq, + .endboot = NULL, + .suspend = imx_lpuart_suspend, + .resume = imx_lpuart_resume, + .tx_ready = imx_lpuart_tx_ready, + .putc = imx_lpuart_putc, + .getc = imx_lpuart_getc, + .irq = imx_lpuart_irq, + .start_tx = imx_lpuart_start_tx, + .stop_tx = imx_lpuart_stop_tx, + .vuart_info = imx_lpuart_vuart_info, +}; + +static int __init imx_lpuart_init(struct dt_device_node *dev, + const void *data) +{ + const char *config = data; + struct imx_lpuart *uart; + int res; + u64 addr, size; + + if ( strcmp(config, "") ) + printk("WARNING: UART configuration is not supported\n"); + + uart = &imx8_com; + + uart->baud = 115200; + uart->data_bits = 8; + uart->parity = 0; + uart->stop_bits = 1; + + res = dt_device_get_address(dev, 0, &addr, &size); + if ( res ) + { + printk("imx8-lpuart: Unable to retrieve the base" + " address of the UART\n"); + return res; + } + + res = platform_get_irq(dev, 0); + if ( res < 0 ) + { + printk("imx8-lpuart: Unable to retrieve the IRQ\n"); + return -EINVAL; + } + uart->irq = res; + + uart->regs = ioremap_nocache(addr, size); + if ( !uart->regs ) + { + printk("imx8-lpuart: Unable to map the UART memory\n"); + return -ENOMEM; + } + + uart->vuart.base_addr = addr; + uart->vuart.size = size; + uart->vuart.data_off = UARTDATA; + /* tmp from uboot */ + uart->vuart.status_off = UARTSTAT; + uart->vuart.status = UARTSTAT_TDRE; + + /* Register with generic serial driver */ + serial_register_uart(SERHND_DTUART, &imx_lpuart_driver, uart); + + dt_device_set_used_by(dev, DOMID_XEN); + + return 0; +} + +static const struct dt_device_match imx_lpuart_dt_compat[] __initconst = +{ + DT_MATCH_COMPATIBLE("fsl,imx8qm-lpuart"), + { /* sentinel */ }, +}; + +DT_DEVICE_START(imx_lpuart, "i.MX LPUART", DEVICE_SERIAL) + .dt_match = imx_lpuart_dt_compat, + .init = imx_lpuart_init, +DT_DEVICE_END + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * indent-tabs-mode: nil + * End: + */ From patchwork Fri Apr 8 14:09:32 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Peng Fan (OSS)" X-Patchwork-Id: 12806745 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F0089C433EF for ; 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the platform specific options are deprecated and will soon be removed. + config EARLY_UART_CHOICE_IMX_LPUART + select EARLY_UART_IMX_LPUART + depends on ARM_64 + bool "Early printk via i.MX LPUART" + help + Say Y here if you wish the early printk to direct their + output to a i.MX LPUART. You can use this option to + provide the parameters for the i.MX LPUART rather than + selecting one of the platform specific options below if + you know the parameters for the port. config EARLY_UART_CHOICE_MESON select EARLY_UART_MESON depends on ARM_64 @@ -186,6 +196,9 @@ config EARLY_UART_CADENCE config EARLY_UART_EXYNOS4210 select EARLY_PRINTK bool +config EARLY_UART_IMX_LPUART + select EARLY_PRINTK + bool config EARLY_UART_MESON select EARLY_PRINTK bool @@ -283,6 +296,7 @@ config EARLY_PRINTK_INC default "debug-8250.inc" if EARLY_UART_8250 default "debug-cadence.inc" if EARLY_UART_CADENCE default "debug-exynos4210.inc" if EARLY_UART_EXYNOS4210 + default "debug-imx-lpuart.inc" if EARLY_UART_IMX_LPUART default "debug-meson.inc" if EARLY_UART_MESON default "debug-mvebu.inc" if EARLY_UART_MVEBU default "debug-pl011.inc" if EARLY_UART_PL011 diff --git a/xen/arch/arm/arm64/debug-imx-lpuart.inc b/xen/arch/arm/arm64/debug-imx-lpuart.inc new file mode 100644 index 0000000000..f68252da86 --- /dev/null +++ b/xen/arch/arm/arm64/debug-imx-lpuart.inc @@ -0,0 +1,52 @@ +/* + * xen/arch/arm/arm64/debug-imx-lpuart.inc + * + * i.MX8QM specific debug code + * + * Peng Fan + * Copyright 2022 NXP + * + * 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. + */ + +#include + +.macro early_uart_init wb wc wd +/* Already initialized in bootloader */ +.endm + +/* + * Wait LPUART to be ready to transmit + * rb: register which contains the UART base address + * rc: scratch register + */ +.macro early_uart_ready xb, c +1: + ldr w\c, [\xb, #UARTSTAT] /* <- Flag register */ + tst w\c, #UARTSTAT_TDRE /* Check FIFO EMPTY bit */ + beq 1b /* Wait for the UART to be ready */ +.endm + +/* + * LPUART transmit character + * rb: register which contains the UART base address + * rt: register which contains the character to transmit + */ +.macro early_uart_transmit xb, wt + str \wt, [\xb, #UARTDATA] /* -> Data Register */ +.endm + +/* + * Local variables: + * mode: ASM + * indent-tabs-mode: nil + * End: + */