From: Stoica Cosmin-Stefan cosminstefan.stoica@freescale.com
The Linflex module is integrated on some NXP automotive SoCs part of the former Freescale portfolio, like S32V234, an SoC for Advanced Driver Assistance Systems.
Original-signed-off-by: Stoica Cosmin-Stefan cosminstefan.stoica@freescale.com Original-signed-off-by: Chircu Bogdan Bogdan.Chircu@freescale.com Original-signed-off-by: Depons Eric eric.depons@freescale.com Original-signed-off-by: Eddy Petrișor eddy.petrisor@gmail.com
Signed-off-by: Eddy Petrișor eddy.petrisor@gmail.com ---
Notes: Changes in v2: Added support for device model. Compatibility with non-DM code is kept for easier synchronization with the code on the vendor branch where the conversion to DM is not done for all boards.
Changes in v3: Removed non-DM compatibility, as requested.
Changes in v4: Corrected typo: s/_debUG_uart_init/_debug_uart_init/
drivers/serial/Makefile | 1 + drivers/serial/serial_linflexuart.c | 221 ++++++++++++++++++++++++++++++++++++ 2 files changed, 222 insertions(+) create mode 100644 drivers/serial/serial_linflexuart.c
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index 9def128..c45cf5d 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -34,6 +34,7 @@ obj-$(CONFIG_SCIF_CONSOLE) += serial_sh.o obj-$(CONFIG_ZYNQ_SERIAL) += serial_zynq.o obj-$(CONFIG_BFIN_SERIAL) += serial_bfin.o obj-$(CONFIG_FSL_LPUART) += serial_lpuart.o +obj-$(CONFIG_FSL_LINFLEXUART) += serial_linflexuart.o obj-$(CONFIG_ARC_SERIAL) += serial_arc.o obj-$(CONFIG_UNIPHIER_SERIAL) += serial_uniphier.o obj-$(CONFIG_STM32_SERIAL) += serial_stm32.o diff --git a/drivers/serial/serial_linflexuart.c b/drivers/serial/serial_linflexuart.c new file mode 100644 index 0000000..2826397 --- /dev/null +++ b/drivers/serial/serial_linflexuart.c @@ -0,0 +1,221 @@ +/* + * (C) Copyright 2013-2016 Freescale Semiconductor, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <errno.h> +#include <watchdog.h> +#include <asm/io.h> +#include <serial.h> +#include <linux/compiler.h> +#include <asm/arch/imx-regs.h> +#include <asm/arch/clock.h> + +#define US1_TDRE (1 << 7) +#define US1_RDRF (1 << 5) +#define UC2_TE (1 << 3) +#define LINCR1_INIT (1 << 0) +#define LINCR1_MME (1 << 4) +#define LINCR1_BF (1 << 7) +#define LINSR_LINS_INITMODE (0x00001000) +#define LINSR_LINS_MASK (0x0000F000) +#define UARTCR_UART (1 << 0) +#define UARTCR_WL0 (1 << 1) +#define UARTCR_PCE (1 << 2) +#define UARTCR_PC0 (1 << 3) +#define UARTCR_TXEN (1 << 4) +#define UARTCR_RXEN (1 << 5) +#define UARTCR_PC1 (1 << 6) +#define UARTSR_DTF (1 << 1) +#define UARTSR_DRF (1 << 2) +#define UARTSR_RMB (1 << 9) + +DECLARE_GLOBAL_DATA_PTR; + +#ifndef CONFIG_DM_SERIAL +#error "The linflex serial driver does not have non-DM support." +#endif + +static void _linflex_serial_setbrg(struct linflex_fsl *base, int baudrate) +{ + u32 clk = mxc_get_clock(MXC_UART_CLK); + u32 ibr, fbr; + + if (!baudrate) + baudrate = CONFIG_BAUDRATE; + + ibr = (u32) (clk / (16 * gd->baudrate)); + fbr = (u32) (clk % (16 * gd->baudrate)) * 16; + + __raw_writel(ibr, &base->linibrr); + __raw_writel(fbr, &base->linfbrr); +} + +static int _linflex_serial_getc(struct linflex_fsl *base) +{ + char c; + + if (!(__raw_readb(&base->uartsr) & UARTSR_DRF)) + return -EAGAIN; + + if (!(__raw_readl(&base->uartsr) & UARTSR_RMB)) + return -EAGAIN; + + c = __raw_readl(&base->bdrm); + __raw_writeb((__raw_readb(&base->uartsr) | (UARTSR_DRF | UARTSR_RMB)), + &base->uartsr); + return c; +} + +static int _linflex_serial_putc(struct linflex_fsl *base, const char c) +{ + __raw_writeb(c, &base->bdrl); + + + if (!(__raw_readb(&base->uartsr) & UARTSR_DTF)) + return -EAGAIN; + + __raw_writeb((__raw_readb(&base->uartsr) | UARTSR_DTF), &base->uartsr); + + return 0; +} + +/* + * Initialise the serial port with the given baudrate. The settings + * are always 8 data bits, no parity, 1 stop bit, no start bits. + */ +static int _linflex_serial_init(struct linflex_fsl *base) +{ + volatile u32 ctrl; + + /* set the Linflex in master mode amd activate by-pass filter */ + ctrl = LINCR1_BF | LINCR1_MME; + __raw_writel(ctrl, &base->lincr1); + + /* init mode */ + ctrl |= LINCR1_INIT; + __raw_writel(ctrl, &base->lincr1); + + /* waiting for init mode entry - TODO: add a timeout */ + while ((__raw_readl(&base->linsr) & LINSR_LINS_MASK) != + LINSR_LINS_INITMODE); + + /* set UART bit to allow writing other bits */ + __raw_writel(UARTCR_UART, &base->uartcr); + + /* provide data bits, parity, stop bit, etc */ + serial_setbrg(); + + /* 8 bit data, no parity, Tx and Rx enabled, UART mode */ + __raw_writel(UARTCR_PC1 | UARTCR_RXEN | UARTCR_TXEN | UARTCR_PC0 + | UARTCR_WL0 | UARTCR_UART, &base->uartcr); + + ctrl = __raw_readl(&base->lincr1); + ctrl &= ~LINCR1_INIT; + __raw_writel(ctrl, &base->lincr1); /* end init mode */ + + return 0; +} + +struct linflex_serial_platdata { + struct linflex_fsl *base_addr; + u8 port_id; /* do we need this? */ +}; + +struct linflex_serial_priv { + struct linflex_fsl *lfuart; +}; + +int linflex_serial_setbrg(struct udevice *dev, int baudrate) +{ + struct linflex_serial_priv *priv = dev_get_priv(dev); + + _linflex_serial_setbrg(priv->lfuart, baudrate); + + return 0; +} + +static int linflex_serial_getc(struct udevice *dev) +{ + struct linflex_serial_priv *priv = dev_get_priv(dev); + + return _linflex_serial_getc(priv->lfuart); +} + +static int linflex_serial_putc(struct udevice *dev, const char ch) +{ + + struct linflex_serial_priv *priv = dev_get_priv(dev); + + return _linflex_serial_putc(priv->lfuart, ch); +} + +static int linflex_serial_pending(struct udevice *dev, bool input) +{ + struct linflex_serial_priv *priv = dev_get_priv(dev); + uint32_t uartsr = __raw_readl(&priv->lfuart->uartsr); + + if (input) + return ((uartsr & UARTSR_DRF) && (uartsr & UARTSR_RMB)) ? 1 : 0; + else + return uartsr & UARTSR_DTF ? 0 : 1; +} + +static void linflex_serial_init_internal(struct linflex_fsl *lfuart) +{ + _linflex_serial_init(lfuart); + _linflex_serial_setbrg(lfuart, CONFIG_BAUDRATE); + return; +} + +static int linflex_serial_probe(struct udevice *dev) +{ + struct linflex_serial_platdata *plat = dev->platdata; + struct linflex_serial_priv *priv = dev_get_priv(dev); + + priv->lfuart = (struct linflex_fsl *)plat->base_addr; + linflex_serial_init_internal(priv->lfuart); + + return 0; +} + +static const struct dm_serial_ops linflex_serial_ops = { + .putc = linflex_serial_putc, + .pending = linflex_serial_pending, + .getc = linflex_serial_getc, + .setbrg = linflex_serial_setbrg, +}; + +U_BOOT_DRIVER(serial_linflex) = { + .name = "serial_linflex", + .id = UCLASS_SERIAL, + .probe = linflex_serial_probe, + .ops = &linflex_serial_ops, + .flags = DM_FLAG_PRE_RELOC, + .priv_auto_alloc_size = sizeof(struct linflex_serial_priv), +}; + +#ifdef CONFIG_DEBUG_UART_LINFLEXUART + +#include <debug_uart.h> + + +static inline void _debug_uart_init(void) +{ + struct linflex_fsl *base = (struct linflex_fsl *)CONFIG_DEBUG_UART_BASE; + + linflex_serial_init_internal(base); +} + +static inline void _debug_uart_putc(int ch) +{ + struct linflex_fsl *base = (struct linflex_fsl *)CONFIG_DEBUG_UART_BASE; + + /* XXX: Is this OK? Should this use the non-DM version? */ + _linflex_serial_putc(base, ch); +} + +#endif /* CONFIG_DEBUG_UART_LINFLEXUART */