This adds a lpuart32 driver. This is a variant of the lpuart driver
that is found on i.MX9 and other SoCs.
Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
---
drivers/serial/Kconfig | 4 +
drivers/serial/Makefile | 1 +
drivers/serial/serial_lpuart32.c | 185 +++++++++++++++++++++++++++++++
include/serial/lpuart32.h | 158 ++++++++++++++++++++++++++
4 files changed, 348 insertions(+)
create mode 100644 drivers/serial/serial_lpuart32.c
create mode 100644 include/serial/lpuart32.h
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 77c827e436..803f6b6aee 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -122,6 +122,10 @@ config DRIVER_SERIAL_LPUART
default y
bool "LPUART serial driver"
+config DRIVER_SERIAL_LPUART32
+ depends on ARCH_IMX
+ bool "LPUART32 serial driver"
+
config VIRTIO_CONSOLE
tristate "Virtio console"
depends on VIRTIO
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index bbc517f521..4887e24ee1 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_DRIVER_SERIAL_CADENCE) += serial_cadence.o
obj-$(CONFIG_DRIVER_SERIAL_EFI_STDIO) += efi-stdio.o
obj-$(CONFIG_DRIVER_SERIAL_DIGIC) += serial_digic.o
obj-$(CONFIG_DRIVER_SERIAL_LPUART) += serial_lpuart.o
+obj-$(CONFIG_DRIVER_SERIAL_LPUART32) += serial_lpuart32.o
obj-$(CONFIG_VIRTIO_CONSOLE) += virtio_console.o
obj-$(CONFIG_SERIAL_SIFIVE) += serial_sifive.o
obj-$(CONFIG_SERIAL_SBI) += serial_sbi.o
diff --git a/drivers/serial/serial_lpuart32.c b/drivers/serial/serial_lpuart32.c
new file mode 100644
index 0000000000..0f3e7c7a04
--- /dev/null
+++ b/drivers/serial/serial_lpuart32.c
@@ -0,0 +1,185 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023 Pengutronix
+ */
+
+#include <common.h>
+#include <driver.h>
+#include <init.h>
+#include <malloc.h>
+#include <notifier.h>
+#include <io.h>
+#include <of.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <serial/lpuart32.h>
+
+struct lpuart32_devtype_data {
+ unsigned int reg_offs;
+};
+
+struct lpuart32 {
+ struct console_device cdev;
+ int baudrate;
+ int dte_mode;
+ struct notifier_block notify;
+ struct resource *io;
+ void __iomem *base;
+ struct clk *clk;
+};
+
+static struct lpuart32 *cdev_to_lpuart32(struct console_device *cdev)
+{
+ return container_of(cdev, struct lpuart32, cdev);
+}
+
+static void lpuart32_enable(struct lpuart32 *lpuart32)
+{
+ writel(LPUART32_UARTCTRL_TE | LPUART32_UARTCTRL_RE,
+ lpuart32->base + LPUART32_UARTCTRL);
+}
+
+static void lpuart32_disable(struct lpuart32 *lpuart32)
+{
+ writel(0, lpuart32->base + LPUART32_UARTCTRL);
+}
+
+static int lpuart32_serial_setbaudrate(struct console_device *cdev,
+ int baudrate)
+{
+ struct lpuart32 *lpuart32 = cdev_to_lpuart32(cdev);
+
+ lpuart32_disable(lpuart32);
+
+ /*
+ * We treat baudrate of 0 as a request to disable UART
+ */
+ if (baudrate) {
+ lpuart32_setbrg(lpuart32->base, clk_get_rate(lpuart32->clk),
+ baudrate);
+ lpuart32_enable(lpuart32);
+ }
+
+ lpuart32->baudrate = baudrate;
+
+ return 0;
+}
+
+static int lpuart32_serial_getc(struct console_device *cdev)
+{
+ struct lpuart32 *lpuart32 = cdev_to_lpuart32(cdev);
+
+ while (!(readl(lpuart32->base + LPUART32_UARTSTAT) & LPUART32_UARTSTAT_RDRF));
+
+ return readl(lpuart32->base + LPUART32_UARTDATA) & 0xff;
+}
+
+static void lpuart32_serial_putc(struct console_device *cdev, char c)
+{
+ struct lpuart32 *lpuart32 = cdev_to_lpuart32(cdev);
+
+ lpuart32_putc(lpuart32->base, c);
+}
+
+/* Test whether a character is in the RX buffer */
+static int lpuart32_serial_tstc(struct console_device *cdev)
+{
+ struct lpuart32 *lpuart32 = cdev_to_lpuart32(cdev);
+
+ return readl(lpuart32->base + LPUART32_UARTSTAT) & LPUART32_UARTSTAT_RDRF;
+}
+
+static void lpuart32_serial_flush(struct console_device *cdev)
+{
+}
+
+static int lpuart32_serial_probe(struct device *dev)
+{
+ int ret;
+ struct console_device *cdev;
+ struct lpuart32 *lpuart32;
+ const char *devname;
+ struct lpuart32_devtype_data *devtype;
+
+ ret = dev_get_drvdata(dev, (const void **)&devtype);
+ if (ret)
+ return ret;
+
+ lpuart32 = xzalloc(sizeof(*lpuart32));
+ cdev = &lpuart32->cdev;
+ dev->priv = lpuart32;
+
+ lpuart32->io = dev_request_mem_resource(dev, 0);
+ if (IS_ERR(lpuart32->io)) {
+ ret = PTR_ERR(lpuart32->io);
+ goto err_free;
+ }
+ lpuart32->base = IOMEM(lpuart32->io->start) + devtype->reg_offs;
+
+ lpuart32->clk = clk_get(dev, NULL);
+ if (IS_ERR(lpuart32->clk)) {
+ ret = PTR_ERR(lpuart32->clk);
+ dev_err(dev, "Failed to get UART clock %d\n", ret);
+ goto io_release;
+ }
+
+ ret = clk_enable(lpuart32->clk);
+ if (ret) {
+ dev_err(dev, "Failed to enable UART clock %d\n", ret);
+ goto io_release;
+ }
+
+ cdev->dev = dev;
+ cdev->tstc = lpuart32_serial_tstc;
+ cdev->putc = lpuart32_serial_putc;
+ cdev->getc = lpuart32_serial_getc;
+ cdev->flush = lpuart32_serial_flush;
+ cdev->setbrg = lpuart32_serial_setbaudrate;
+
+ if (dev->of_node) {
+ devname = of_alias_get(dev->of_node);
+ if (devname) {
+ cdev->devname = xstrdup(devname);
+ cdev->devid = DEVICE_ID_SINGLE;
+ }
+ }
+
+ cdev->linux_console_name = "ttyLP";
+ cdev->linux_earlycon_name = "lpuart";
+ cdev->phys_base = lpuart32->base;
+
+ lpuart32_setup(lpuart32->base, clk_get_rate(lpuart32->clk));
+
+ ret = console_register(cdev);
+ if (!ret)
+ return 0;
+
+ clk_put(lpuart32->clk);
+io_release:
+ release_region(lpuart32->io);
+err_free:
+ free(lpuart32);
+
+ return ret;
+}
+
+static struct lpuart32_devtype_data imx7ulp_data = {
+ .reg_offs = 0x10,
+};
+
+static struct of_device_id lpuart32_serial_dt_ids[] = {
+ {
+ .compatible = "fsl,imx7ulp-lpuart",
+ .data = &imx7ulp_data,
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, lpuart32_serial_dt_ids);
+
+static struct driver lpuart32_serial_driver = {
+ .name = "lpuart32-serial",
+ .probe = lpuart32_serial_probe,
+ .of_compatible = DRV_OF_COMPAT(lpuart32_serial_dt_ids),
+};
+console_platform_driver(lpuart32_serial_driver);
diff --git a/include/serial/lpuart32.h b/include/serial/lpuart32.h
new file mode 100644
index 0000000000..bcfd067113
--- /dev/null
+++ b/include/serial/lpuart32.h
@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 2016 Zodiac Inflight Innovation
+ * Author: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
+ *
+ * Based on code found in Linux kernel and U-Boot.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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 __lpuart32_H__
+#define __lpuart32_H__
+
+
+/* 32-bit register definition */
+#define LPUART32_UARTBAUD 0x00
+#define LPUART32_UARTSTAT 0x04
+#define LPUART32_UARTCTRL 0x08
+#define LPUART32_UARTDATA 0x0C
+#define LPUART32_UARTMATCH 0x10
+#define LPUART32_UARTMODIR 0x14
+#define LPUART32_UARTFIFO 0x18
+#define LPUART32_UARTWATER 0x1c
+
+#define LPUART32_UARTBAUD_MAEN1 0x80000000
+#define LPUART32_UARTBAUD_MAEN2 0x40000000
+#define LPUART32_UARTBAUD_M10 0x20000000
+#define LPUART32_UARTBAUD_TDMAE 0x00800000
+#define LPUART32_UARTBAUD_RDMAE 0x00200000
+#define LPUART32_UARTBAUD_MATCFG 0x00400000
+#define LPUART32_UARTBAUD_BOTHEDGE 0x00020000
+#define LPUART32_UARTBAUD_RESYNCDIS 0x00010000
+#define LPUART32_UARTBAUD_LBKDIE 0x00008000
+#define LPUART32_UARTBAUD_RXEDGIE 0x00004000
+#define LPUART32_UARTBAUD_SBNS 0x00002000
+#define LPUART32_UARTBAUD_SBR 0x00000000
+#define LPUART32_UARTBAUD_SBR_MASK 0x1fff
+#define LPUART32_UARTBAUD_OSR_MASK 0x1f
+#define LPUART32_UARTBAUD_OSR_SHIFT 24
+
+#define LPUART32_UARTSTAT_LBKDIF 0x80000000
+#define LPUART32_UARTSTAT_RXEDGIF 0x40000000
+#define LPUART32_UARTSTAT_MSBF 0x20000000
+#define LPUART32_UARTSTAT_RXINV 0x10000000
+#define LPUART32_UARTSTAT_RWUID 0x08000000
+#define LPUART32_UARTSTAT_BRK13 0x04000000
+#define LPUART32_UARTSTAT_LBKDE 0x02000000
+#define LPUART32_UARTSTAT_RAF 0x01000000
+#define LPUART32_UARTSTAT_TDRE 0x00800000
+#define LPUART32_UARTSTAT_TC 0x00400000
+#define LPUART32_UARTSTAT_RDRF 0x00200000
+#define LPUART32_UARTSTAT_IDLE 0x00100000
+#define LPUART32_UARTSTAT_OR 0x00080000
+#define LPUART32_UARTSTAT_NF 0x00040000
+#define LPUART32_UARTSTAT_FE 0x00020000
+#define LPUART32_UARTSTAT_PE 0x00010000
+#define LPUART32_UARTSTAT_MA1F 0x00008000
+#define LPUART32_UARTSTAT_M21F 0x00004000
+
+#define LPUART32_UARTCTRL_R8T9 0x80000000
+#define LPUART32_UARTCTRL_R9T8 0x40000000
+#define LPUART32_UARTCTRL_TXDIR 0x20000000
+#define LPUART32_UARTCTRL_TXINV 0x10000000
+#define LPUART32_UARTCTRL_ORIE 0x08000000
+#define LPUART32_UARTCTRL_NEIE 0x04000000
+#define LPUART32_UARTCTRL_FEIE 0x02000000
+#define LPUART32_UARTCTRL_PEIE 0x01000000
+#define LPUART32_UARTCTRL_TIE 0x00800000
+#define LPUART32_UARTCTRL_TCIE 0x00400000
+#define LPUART32_UARTCTRL_RIE 0x00200000
+#define LPUART32_UARTCTRL_ILIE 0x00100000
+#define LPUART32_UARTCTRL_TE 0x00080000
+#define LPUART32_UARTCTRL_RE 0x00040000
+#define LPUART32_UARTCTRL_RWU 0x00020000
+#define LPUART32_UARTCTRL_SBK 0x00010000
+#define LPUART32_UARTCTRL_MA1IE 0x00008000
+#define LPUART32_UARTCTRL_MA2IE 0x00004000
+#define LPUART32_UARTCTRL_IDLECFG GENMASK(10, 8)
+#define LPUART32_UARTCTRL_LOOPS 0x00000080
+#define LPUART32_UARTCTRL_DOZEEN 0x00000040
+#define LPUART32_UARTCTRL_RSRC 0x00000020
+#define LPUART32_UARTCTRL_M 0x00000010
+#define LPUART32_UARTCTRL_WAKE 0x00000008
+#define LPUART32_UARTCTRL_ILT 0x00000004
+#define LPUART32_UARTCTRL_PE 0x00000002
+#define LPUART32_UARTCTRL_PT 0x00000001
+
+#define LPUART32_UARTDATA_NOISY 0x00008000
+#define LPUART32_UARTDATA_PARITYE 0x00004000
+#define LPUART32_UARTDATA_FRETSC 0x00002000
+#define LPUART32_UARTDATA_RXEMPT 0x00001000
+#define LPUART32_UARTDATA_IDLINE 0x00000800
+#define LPUART32_UARTDATA_MASK 0x3ff
+
+#define LPUART32_UARTMODIR_IREN 0x00020000
+#define LPUART32_UARTMODIR_RTSWATER GENMASK(10, 8)
+#define LPUART32_UARTMODIR_TXCTSSRC 0x00000020
+#define LPUART32_UARTMODIR_TXCTSC 0x00000010
+#define LPUART32_UARTMODIR_RXRTSE 0x00000008
+#define LPUART32_UARTMODIR_TXRTSPOL 0x00000004
+#define LPUART32_UARTMODIR_TXRTSE 0x00000002
+#define LPUART32_UARTMODIR_TXCTSE 0x00000001
+
+#define LPUART32_UARTFIFO_TXEMPT 0x00800000
+#define LPUART32_UARTFIFO_RXEMPT 0x00400000
+#define LPUART32_UARTFIFO_TXOF 0x00020000
+#define LPUART32_UARTFIFO_RXUF 0x00010000
+#define LPUART32_UARTFIFO_TXFLUSH 0x00008000
+#define LPUART32_UARTFIFO_RXFLUSH 0x00004000
+#define LPUART32_UARTFIFO_RXIDEN GENMASK(12, 10)
+#define LPUART32_UARTFIFO_TXOFE 0x00000200
+#define LPUART32_UARTFIFO_RXUFE 0x00000100
+#define LPUART32_UARTFIFO_TXFE 0x00000080
+#define LPUART32_UARTFIFO_FIFOSIZE_MASK 0x7
+#define LPUART32_UARTFIFO_TXSIZE_OFF 4
+#define LPUART32_UARTFIFO_RXFE 0x00000008
+#define LPUART32_UARTFIFO_RXSIZE_OFF 0
+#define LPUART32_UARTFIFO_DEPTH(x) (0x1 << ((x) ? ((x) + 1) : 0))
+
+#define LPUART32_UARTWATER_COUNT_MASK 0xff
+#define LPUART32_UARTWATER_TXCNT_OFF 8
+#define LPUART32_UARTWATER_RXCNT_OFF 24
+#define LPUART32_UARTWATER_WATER_MASK 0xff
+#define LPUART32_UARTWATER_TXWATER_OFF 0
+#define LPUART32_UARTWATER_RXWATER_OFF 16
+
+static inline void lpuart32_setbrg(void __iomem *base,
+ unsigned int refclock,
+ unsigned int baudrate)
+{
+ u32 sbr;
+
+ sbr = (refclock / (16 * baudrate));
+ writel(sbr, base + LPUART32_UARTBAUD);
+}
+
+static inline void lpuart32_setup(void __iomem *base,
+ unsigned int refclock)
+{
+ lpuart32_setbrg(base, refclock, CONFIG_BAUDRATE);
+ writel(LPUART32_UARTCTRL_TE | LPUART32_UARTCTRL_RE, base + LPUART32_UARTCTRL);
+}
+
+static inline void lpuart32_putc(void __iomem *base, int c)
+{
+ while (!(readl(base + LPUART32_UARTSTAT) & LPUART32_UARTSTAT_TDRE));
+
+ writel(c, base + LPUART32_UARTDATA);
+}
+
+#endif
--
2.39.2
