| /* |
| * (c) 2007 Sascha Hauer <s.hauer@pengutronix.de> |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| */ |
| |
| #include <common.h> |
| #include <dm.h> |
| #include <errno.h> |
| #include <watchdog.h> |
| #include <asm/arch/imx-regs.h> |
| #include <asm/arch/clock.h> |
| #include <dm/platform_data/serial_mxc.h> |
| #include <serial.h> |
| #include <linux/compiler.h> |
| #include <asm/imx-common/sys_proto.h> |
| |
| /* UART Control Register Bit Fields.*/ |
| #define URXD_CHARRDY (1<<15) |
| #define URXD_ERR (1<<14) |
| #define URXD_OVRRUN (1<<13) |
| #define URXD_FRMERR (1<<12) |
| #define URXD_BRK (1<<11) |
| #define URXD_PRERR (1<<10) |
| #define URXD_RX_DATA (0xFF) |
| #define UCR1_ADEN (1<<15) /* Auto dectect interrupt */ |
| #define UCR1_ADBR (1<<14) /* Auto detect baud rate */ |
| #define UCR1_TRDYEN (1<<13) /* Transmitter ready interrupt enable */ |
| #define UCR1_IDEN (1<<12) /* Idle condition interrupt */ |
| #define UCR1_RRDYEN (1<<9) /* Recv ready interrupt enable */ |
| #define UCR1_RDMAEN (1<<8) /* Recv ready DMA enable */ |
| #define UCR1_IREN (1<<7) /* Infrared interface enable */ |
| #define UCR1_TXMPTYEN (1<<6) /* Transimitter empty interrupt enable */ |
| #define UCR1_RTSDEN (1<<5) /* RTS delta interrupt enable */ |
| #define UCR1_SNDBRK (1<<4) /* Send break */ |
| #define UCR1_TDMAEN (1<<3) /* Transmitter ready DMA enable */ |
| #define UCR1_UARTCLKEN (1<<2) /* UART clock enabled */ |
| #define UCR1_DOZE (1<<1) /* Doze */ |
| #define UCR1_UARTEN (1<<0) /* UART enabled */ |
| #define UCR2_ESCI (1<<15) /* Escape seq interrupt enable */ |
| #define UCR2_IRTS (1<<14) /* Ignore RTS pin */ |
| #define UCR2_CTSC (1<<13) /* CTS pin control */ |
| #define UCR2_CTS (1<<12) /* Clear to send */ |
| #define UCR2_ESCEN (1<<11) /* Escape enable */ |
| #define UCR2_PREN (1<<8) /* Parity enable */ |
| #define UCR2_PROE (1<<7) /* Parity odd/even */ |
| #define UCR2_STPB (1<<6) /* Stop */ |
| #define UCR2_WS (1<<5) /* Word size */ |
| #define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */ |
| #define UCR2_TXEN (1<<2) /* Transmitter enabled */ |
| #define UCR2_RXEN (1<<1) /* Receiver enabled */ |
| #define UCR2_SRST (1<<0) /* SW reset */ |
| #define UCR3_DTREN (1<<13) /* DTR interrupt enable */ |
| #define UCR3_PARERREN (1<<12) /* Parity enable */ |
| #define UCR3_FRAERREN (1<<11) /* Frame error interrupt enable */ |
| #define UCR3_DSR (1<<10) /* Data set ready */ |
| #define UCR3_DCD (1<<9) /* Data carrier detect */ |
| #define UCR3_RI (1<<8) /* Ring indicator */ |
| #define UCR3_ADNIMP (1<<7) /* Autobaud Detection Not Improved */ |
| #define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */ |
| #define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */ |
| #define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */ |
| #define UCR3_REF25 (1<<3) /* Ref freq 25 MHz */ |
| #define UCR3_REF30 (1<<2) /* Ref Freq 30 MHz */ |
| #define UCR3_INVT (1<<1) /* Inverted Infrared transmission */ |
| #define UCR3_BPEN (1<<0) /* Preset registers enable */ |
| #define UCR4_CTSTL_32 (32<<10) /* CTS trigger level (32 chars) */ |
| #define UCR4_INVR (1<<9) /* Inverted infrared reception */ |
| #define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */ |
| #define UCR4_WKEN (1<<7) /* Wake interrupt enable */ |
| #define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */ |
| #define UCR4_IRSC (1<<5) /* IR special case */ |
| #define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */ |
| #define UCR4_BKEN (1<<2) /* Break condition interrupt enable */ |
| #define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */ |
| #define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */ |
| #define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */ |
| #define UFCR_RFDIV (7<<7) /* Reference freq divider mask */ |
| #define UFCR_RFDIV_SHF 7 /* Reference freq divider shift */ |
| #define UFCR_DCEDTE (1<<6) /* DTE mode select */ |
| #define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */ |
| #define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */ |
| #define USR1_RTSS (1<<14) /* RTS pin status */ |
| #define USR1_TRDY (1<<13) /* Transmitter ready interrupt/dma flag */ |
| #define USR1_RTSD (1<<12) /* RTS delta */ |
| #define USR1_ESCF (1<<11) /* Escape seq interrupt flag */ |
| #define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */ |
| #define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */ |
| #define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */ |
| #define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */ |
| #define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */ |
| #define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */ |
| #define USR2_ADET (1<<15) /* Auto baud rate detect complete */ |
| #define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */ |
| #define USR2_DTRF (1<<13) /* DTR edge interrupt flag */ |
| #define USR2_IDLE (1<<12) /* Idle condition */ |
| #define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */ |
| #define USR2_WAKE (1<<7) /* Wake */ |
| #define USR2_RTSF (1<<4) /* RTS edge interrupt flag */ |
| #define USR2_TXDC (1<<3) /* Transmitter complete */ |
| #define USR2_BRCD (1<<2) /* Break condition */ |
| #define USR2_ORE (1<<1) /* Overrun error */ |
| #define USR2_RDR (1<<0) /* Recv data ready */ |
| #define UTS_FRCPERR (1<<13) /* Force parity error */ |
| #define UTS_LOOP (1<<12) /* Loop tx and rx */ |
| #define UTS_TXEMPTY (1<<6) /* TxFIFO empty */ |
| #define UTS_RXEMPTY (1<<5) /* RxFIFO empty */ |
| #define UTS_TXFULL (1<<4) /* TxFIFO full */ |
| #define UTS_RXFULL (1<<3) /* RxFIFO full */ |
| #define UTS_SOFTRST (1<<0) /* Software reset */ |
| |
| DECLARE_GLOBAL_DATA_PTR; |
| |
| #ifndef CONFIG_DM_SERIAL |
| |
| #ifndef CONFIG_MXC_UART_BASE |
| #error "define CONFIG_MXC_UART_BASE to use the MXC UART driver" |
| #endif |
| |
| #define UART_PHYS CONFIG_MXC_UART_BASE |
| |
| #define __REG(x) (*((volatile u32 *)(x))) |
| |
| /* Register definitions */ |
| #define URXD 0x0 /* Receiver Register */ |
| #define UTXD 0x40 /* Transmitter Register */ |
| #define UCR1 0x80 /* Control Register 1 */ |
| #define UCR2 0x84 /* Control Register 2 */ |
| #define UCR3 0x88 /* Control Register 3 */ |
| #define UCR4 0x8c /* Control Register 4 */ |
| #define UFCR 0x90 /* FIFO Control Register */ |
| #define USR1 0x94 /* Status Register 1 */ |
| #define USR2 0x98 /* Status Register 2 */ |
| #define UESC 0x9c /* Escape Character Register */ |
| #define UTIM 0xa0 /* Escape Timer Register */ |
| #define UBIR 0xa4 /* BRM Incremental Register */ |
| #define UBMR 0xa8 /* BRM Modulator Register */ |
| #define UBRC 0xac /* Baud Rate Count Register */ |
| #define UTS 0xb4 /* UART Test Register (mx31) */ |
| |
| #define TXTL 2 /* reset default */ |
| #define RXTL 1 /* reset default */ |
| #define RFDIV 4 /* divide input clock by 2 */ |
| |
| static void mxc_serial_setbrg(void) |
| { |
| u32 clk = imx_get_uartclk(); |
| |
| if (!gd->baudrate) |
| gd->baudrate = CONFIG_BAUDRATE; |
| |
| __REG(UART_PHYS + UFCR) = (RFDIV << UFCR_RFDIV_SHF) |
| | (TXTL << UFCR_TXTL_SHF) |
| | (RXTL << UFCR_RXTL_SHF); |
| __REG(UART_PHYS + UBIR) = 0xf; |
| __REG(UART_PHYS + UBMR) = clk / (2 * gd->baudrate); |
| |
| } |
| |
| static int mxc_serial_getc(void) |
| { |
| while (__REG(UART_PHYS + UTS) & UTS_RXEMPTY) |
| WATCHDOG_RESET(); |
| return (__REG(UART_PHYS + URXD) & URXD_RX_DATA); /* mask out status from upper word */ |
| } |
| |
| static void mxc_serial_putc(const char c) |
| { |
| /* If \n, also do \r */ |
| if (c == '\n') |
| serial_putc('\r'); |
| |
| __REG(UART_PHYS + UTXD) = c; |
| |
| /* wait for transmitter to be ready */ |
| while (!(__REG(UART_PHYS + UTS) & UTS_TXEMPTY)) |
| WATCHDOG_RESET(); |
| } |
| |
| /* |
| * Test whether a character is in the RX buffer |
| */ |
| static int one_time_rx_line_always_low_workaround_needed = 1; |
| static int mxc_serial_tstc(void) |
| { |
| /* If receive fifo is empty, return false */ |
| if (__REG(UART_PHYS + UTS) & UTS_RXEMPTY) |
| return 0; |
| |
| /* Empty RX FIFO if receiver is stuck because of RXD line being low */ |
| if (one_time_rx_line_always_low_workaround_needed) { |
| one_time_rx_line_always_low_workaround_needed = 0; |
| if (!(__REG(UART_PHYS + USR2) & USR2_RDR)) { |
| while (!(__REG(UART_PHYS + UTS) & UTS_RXEMPTY)) { |
| (void) __REG(UART_PHYS + URXD); |
| } |
| return 0; |
| } |
| } |
| |
| return 1; |
| } |
| |
| /* |
| * 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 mxc_serial_init(void) |
| { |
| __REG(UART_PHYS + UCR1) = 0x0; |
| __REG(UART_PHYS + UCR2) = 0x0; |
| |
| while (!(__REG(UART_PHYS + UCR2) & UCR2_SRST)); |
| |
| __REG(UART_PHYS + UCR3) = 0x0704 | UCR3_ADNIMP; |
| __REG(UART_PHYS + UCR4) = 0x8000; |
| __REG(UART_PHYS + UESC) = 0x002b; |
| __REG(UART_PHYS + UTIM) = 0x0; |
| |
| __REG(UART_PHYS + UTS) = 0x0; |
| |
| serial_setbrg(); |
| |
| __REG(UART_PHYS + UCR2) = UCR2_WS | UCR2_IRTS | UCR2_RXEN | UCR2_TXEN | UCR2_SRST; |
| |
| __REG(UART_PHYS + UCR1) = UCR1_UARTEN; |
| |
| return 0; |
| } |
| |
| static struct serial_device mxc_serial_drv = { |
| .name = "mxc_serial", |
| .start = mxc_serial_init, |
| .stop = NULL, |
| .setbrg = mxc_serial_setbrg, |
| .putc = mxc_serial_putc, |
| .puts = default_serial_puts, |
| .getc = mxc_serial_getc, |
| .tstc = mxc_serial_tstc, |
| }; |
| |
| void mxc_serial_initialize(void) |
| { |
| serial_register(&mxc_serial_drv); |
| } |
| |
| __weak struct serial_device *default_serial_console(void) |
| { |
| return &mxc_serial_drv; |
| } |
| #endif |
| |
| #ifdef CONFIG_DM_SERIAL |
| |
| struct mxc_uart { |
| u32 rxd; |
| u32 spare0[15]; |
| |
| u32 txd; |
| u32 spare1[15]; |
| |
| u32 cr1; |
| u32 cr2; |
| u32 cr3; |
| u32 cr4; |
| |
| u32 fcr; |
| u32 sr1; |
| u32 sr2; |
| u32 esc; |
| |
| u32 tim; |
| u32 bir; |
| u32 bmr; |
| u32 brc; |
| |
| u32 onems; |
| u32 ts; |
| }; |
| |
| int mxc_serial_setbrg(struct udevice *dev, int baudrate) |
| { |
| struct mxc_serial_platdata *plat = dev->platdata; |
| struct mxc_uart *const uart = plat->reg; |
| u32 clk = imx_get_uartclk(); |
| u32 tmp; |
| |
| tmp = 4 << UFCR_RFDIV_SHF; |
| if (plat->use_dte) |
| tmp |= UFCR_DCEDTE; |
| writel(tmp, &uart->fcr); |
| |
| writel(0xf, &uart->bir); |
| writel(clk / (2 * baudrate), &uart->bmr); |
| |
| writel(UCR2_WS | UCR2_IRTS | UCR2_RXEN | UCR2_TXEN | UCR2_SRST, |
| &uart->cr2); |
| writel(UCR1_UARTEN, &uart->cr1); |
| |
| return 0; |
| } |
| |
| static int mxc_serial_probe(struct udevice *dev) |
| { |
| struct mxc_serial_platdata *plat = dev->platdata; |
| struct mxc_uart *const uart = plat->reg; |
| |
| writel(0, &uart->cr1); |
| writel(0, &uart->cr2); |
| while (!(readl(&uart->cr2) & UCR2_SRST)); |
| writel(0x704 | UCR3_ADNIMP, &uart->cr3); |
| writel(0x8000, &uart->cr4); |
| writel(0x2b, &uart->esc); |
| writel(0, &uart->tim); |
| writel(0, &uart->ts); |
| |
| return 0; |
| } |
| |
| static int mxc_serial_getc(struct udevice *dev) |
| { |
| struct mxc_serial_platdata *plat = dev->platdata; |
| struct mxc_uart *const uart = plat->reg; |
| |
| if (readl(&uart->ts) & UTS_RXEMPTY) |
| return -EAGAIN; |
| |
| return readl(&uart->rxd) & URXD_RX_DATA; |
| } |
| |
| static int mxc_serial_putc(struct udevice *dev, const char ch) |
| { |
| struct mxc_serial_platdata *plat = dev->platdata; |
| struct mxc_uart *const uart = plat->reg; |
| |
| if (!(readl(&uart->ts) & UTS_TXEMPTY)) |
| return -EAGAIN; |
| |
| writel(ch, &uart->txd); |
| |
| return 0; |
| } |
| |
| static int mxc_serial_pending(struct udevice *dev, bool input) |
| { |
| struct mxc_serial_platdata *plat = dev->platdata; |
| struct mxc_uart *const uart = plat->reg; |
| uint32_t sr2 = readl(&uart->sr2); |
| |
| if (input) |
| return sr2 & USR2_RDR ? 1 : 0; |
| else |
| return sr2 & USR2_TXDC ? 0 : 1; |
| } |
| |
| static const struct dm_serial_ops mxc_serial_ops = { |
| .putc = mxc_serial_putc, |
| .pending = mxc_serial_pending, |
| .getc = mxc_serial_getc, |
| .setbrg = mxc_serial_setbrg, |
| }; |
| |
| #if CONFIG_IS_ENABLED(OF_CONTROL) |
| static int mxc_serial_ofdata_to_platdata(struct udevice *dev) |
| { |
| struct mxc_serial_platdata *plat = dev->platdata; |
| fdt_addr_t addr; |
| |
| addr = dev_get_addr(dev); |
| if (addr == FDT_ADDR_T_NONE) |
| return -EINVAL; |
| |
| plat->reg = (struct mxc_uart *)addr; |
| |
| plat->use_dte = fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev), |
| "fsl,dte-mode"); |
| return 0; |
| } |
| |
| static const struct udevice_id mxc_serial_ids[] = { |
| { .compatible = "fsl,imx7d-uart" }, |
| { } |
| }; |
| #endif |
| |
| U_BOOT_DRIVER(serial_mxc) = { |
| .name = "serial_mxc", |
| .id = UCLASS_SERIAL, |
| #if CONFIG_IS_ENABLED(OF_CONTROL) |
| .of_match = mxc_serial_ids, |
| .ofdata_to_platdata = mxc_serial_ofdata_to_platdata, |
| .platdata_auto_alloc_size = sizeof(struct mxc_serial_platdata), |
| #endif |
| .probe = mxc_serial_probe, |
| .ops = &mxc_serial_ops, |
| .flags = DM_FLAG_PRE_RELOC, |
| }; |
| #endif |