1194846f3SMichal Simek /* 2194846f3SMichal Simek * Copyright (C) 2012 Michal Simek <monstr@monstr.eu> 3194846f3SMichal Simek * Copyright (C) 2011-2012 Xilinx, Inc. All rights reserved. 4194846f3SMichal Simek * 51a459660SWolfgang Denk * SPDX-License-Identifier: GPL-2.0+ 6194846f3SMichal Simek */ 7194846f3SMichal Simek 8194846f3SMichal Simek #include <common.h> 9c9416b92SMichal Simek #include <fdtdec.h> 10194846f3SMichal Simek #include <watchdog.h> 11194846f3SMichal Simek #include <asm/io.h> 12194846f3SMichal Simek #include <linux/compiler.h> 13194846f3SMichal Simek #include <serial.h> 1419605e2eSSoren Brinkmann #include <asm/arch/clk.h> 15bf834950SMichal Simek #include <asm/arch/hardware.h> 16194846f3SMichal Simek 17c9416b92SMichal Simek DECLARE_GLOBAL_DATA_PTR; 18c9416b92SMichal Simek 19194846f3SMichal Simek #define ZYNQ_UART_SR_TXFULL 0x00000010 /* TX FIFO full */ 20194846f3SMichal Simek #define ZYNQ_UART_SR_RXEMPTY 0x00000002 /* RX FIFO empty */ 21194846f3SMichal Simek 22194846f3SMichal Simek #define ZYNQ_UART_CR_TX_EN 0x00000010 /* TX enabled */ 23194846f3SMichal Simek #define ZYNQ_UART_CR_RX_EN 0x00000004 /* RX enabled */ 24194846f3SMichal Simek #define ZYNQ_UART_CR_TXRST 0x00000002 /* TX logic reset */ 25194846f3SMichal Simek #define ZYNQ_UART_CR_RXRST 0x00000001 /* RX logic reset */ 26194846f3SMichal Simek 27194846f3SMichal Simek #define ZYNQ_UART_MR_PARITY_NONE 0x00000020 /* No parity mode */ 28194846f3SMichal Simek 29194846f3SMichal Simek struct uart_zynq { 30a2425e62SMichal Simek u32 control; /* 0x0 - Control Register [8:0] */ 31a2425e62SMichal Simek u32 mode; /* 0x4 - Mode Register [10:0] */ 32194846f3SMichal Simek u32 reserved1[4]; 33a2425e62SMichal Simek u32 baud_rate_gen; /* 0x18 - Baud Rate Generator [15:0] */ 34194846f3SMichal Simek u32 reserved2[4]; 35a2425e62SMichal Simek u32 channel_sts; /* 0x2c - Channel Status [11:0] */ 36a2425e62SMichal Simek u32 tx_rx_fifo; /* 0x30 - FIFO [15:0] or [7:0] */ 37a2425e62SMichal Simek u32 baud_rate_divider; /* 0x34 - Baud Rate Divider [7:0] */ 38194846f3SMichal Simek }; 39194846f3SMichal Simek 40194846f3SMichal Simek static struct uart_zynq *uart_zynq_ports[2] = { 41bf834950SMichal Simek [0] = (struct uart_zynq *)ZYNQ_SERIAL_BASEADDR0, 42bf834950SMichal Simek [1] = (struct uart_zynq *)ZYNQ_SERIAL_BASEADDR1, 43194846f3SMichal Simek }; 44194846f3SMichal Simek 45194846f3SMichal Simek /* Set up the baud rate in gd struct */ 46194846f3SMichal Simek static void uart_zynq_serial_setbrg(const int port) 47194846f3SMichal Simek { 48194846f3SMichal Simek /* Calculation results. */ 49194846f3SMichal Simek unsigned int calc_bauderror, bdiv, bgen; 50194846f3SMichal Simek unsigned long calc_baud = 0; 51*04bc5c93SMichal Simek unsigned long baud; 5219605e2eSSoren Brinkmann unsigned long clock = get_uart_clk(port); 53194846f3SMichal Simek struct uart_zynq *regs = uart_zynq_ports[port]; 54194846f3SMichal Simek 55*04bc5c93SMichal Simek /* Covering case where input clock is so slow */ 56*04bc5c93SMichal Simek if (clock < 1000000 && gd->baudrate > 4800) 57*04bc5c93SMichal Simek gd->baudrate = 4800; 58*04bc5c93SMichal Simek 59*04bc5c93SMichal Simek baud = gd->baudrate; 60*04bc5c93SMichal Simek 61194846f3SMichal Simek /* master clock 62194846f3SMichal Simek * Baud rate = ------------------ 63194846f3SMichal Simek * bgen * (bdiv + 1) 64194846f3SMichal Simek * 65194846f3SMichal Simek * Find acceptable values for baud generation. 66194846f3SMichal Simek */ 67194846f3SMichal Simek for (bdiv = 4; bdiv < 255; bdiv++) { 68194846f3SMichal Simek bgen = clock / (baud * (bdiv + 1)); 69194846f3SMichal Simek if (bgen < 2 || bgen > 65535) 70194846f3SMichal Simek continue; 71194846f3SMichal Simek 72194846f3SMichal Simek calc_baud = clock / (bgen * (bdiv + 1)); 73194846f3SMichal Simek 74194846f3SMichal Simek /* 75194846f3SMichal Simek * Use first calculated baudrate with 76194846f3SMichal Simek * an acceptable (<3%) error 77194846f3SMichal Simek */ 78194846f3SMichal Simek if (baud > calc_baud) 79194846f3SMichal Simek calc_bauderror = baud - calc_baud; 80194846f3SMichal Simek else 81194846f3SMichal Simek calc_bauderror = calc_baud - baud; 82194846f3SMichal Simek if (((calc_bauderror * 100) / baud) < 3) 83194846f3SMichal Simek break; 84194846f3SMichal Simek } 85194846f3SMichal Simek 86194846f3SMichal Simek writel(bdiv, ®s->baud_rate_divider); 87194846f3SMichal Simek writel(bgen, ®s->baud_rate_gen); 88194846f3SMichal Simek } 89194846f3SMichal Simek 90194846f3SMichal Simek /* Initialize the UART, with...some settings. */ 91194846f3SMichal Simek static int uart_zynq_serial_init(const int port) 92194846f3SMichal Simek { 93194846f3SMichal Simek struct uart_zynq *regs = uart_zynq_ports[port]; 94194846f3SMichal Simek 95194846f3SMichal Simek if (!regs) 96194846f3SMichal Simek return -1; 97194846f3SMichal Simek 98194846f3SMichal Simek /* RX/TX enabled & reset */ 99194846f3SMichal Simek writel(ZYNQ_UART_CR_TX_EN | ZYNQ_UART_CR_RX_EN | ZYNQ_UART_CR_TXRST | \ 100194846f3SMichal Simek ZYNQ_UART_CR_RXRST, ®s->control); 101194846f3SMichal Simek writel(ZYNQ_UART_MR_PARITY_NONE, ®s->mode); /* 8 bit, no parity */ 102194846f3SMichal Simek uart_zynq_serial_setbrg(port); 103194846f3SMichal Simek 104194846f3SMichal Simek return 0; 105194846f3SMichal Simek } 106194846f3SMichal Simek 107194846f3SMichal Simek static void uart_zynq_serial_putc(const char c, const int port) 108194846f3SMichal Simek { 109194846f3SMichal Simek struct uart_zynq *regs = uart_zynq_ports[port]; 110194846f3SMichal Simek 111194846f3SMichal Simek while ((readl(®s->channel_sts) & ZYNQ_UART_SR_TXFULL) != 0) 112194846f3SMichal Simek WATCHDOG_RESET(); 113194846f3SMichal Simek 114194846f3SMichal Simek if (c == '\n') { 115194846f3SMichal Simek writel('\r', ®s->tx_rx_fifo); 116194846f3SMichal Simek while ((readl(®s->channel_sts) & ZYNQ_UART_SR_TXFULL) != 0) 117194846f3SMichal Simek WATCHDOG_RESET(); 118194846f3SMichal Simek } 119194846f3SMichal Simek writel(c, ®s->tx_rx_fifo); 120194846f3SMichal Simek } 121194846f3SMichal Simek 122194846f3SMichal Simek static void uart_zynq_serial_puts(const char *s, const int port) 123194846f3SMichal Simek { 124194846f3SMichal Simek while (*s) 125194846f3SMichal Simek uart_zynq_serial_putc(*s++, port); 126194846f3SMichal Simek } 127194846f3SMichal Simek 128194846f3SMichal Simek static int uart_zynq_serial_tstc(const int port) 129194846f3SMichal Simek { 130194846f3SMichal Simek struct uart_zynq *regs = uart_zynq_ports[port]; 131194846f3SMichal Simek 132194846f3SMichal Simek return (readl(®s->channel_sts) & ZYNQ_UART_SR_RXEMPTY) == 0; 133194846f3SMichal Simek } 134194846f3SMichal Simek 135194846f3SMichal Simek static int uart_zynq_serial_getc(const int port) 136194846f3SMichal Simek { 137194846f3SMichal Simek struct uart_zynq *regs = uart_zynq_ports[port]; 138194846f3SMichal Simek 139194846f3SMichal Simek while (!uart_zynq_serial_tstc(port)) 140194846f3SMichal Simek WATCHDOG_RESET(); 141194846f3SMichal Simek return readl(®s->tx_rx_fifo); 142194846f3SMichal Simek } 143194846f3SMichal Simek 144194846f3SMichal Simek /* Multi serial device functions */ 145194846f3SMichal Simek #define DECLARE_PSSERIAL_FUNCTIONS(port) \ 1466c4da359SMichal Simek static int uart_zynq##port##_init(void) \ 147194846f3SMichal Simek { return uart_zynq_serial_init(port); } \ 1486c4da359SMichal Simek static void uart_zynq##port##_setbrg(void) \ 149194846f3SMichal Simek { return uart_zynq_serial_setbrg(port); } \ 1506c4da359SMichal Simek static int uart_zynq##port##_getc(void) \ 151194846f3SMichal Simek { return uart_zynq_serial_getc(port); } \ 1526c4da359SMichal Simek static int uart_zynq##port##_tstc(void) \ 153194846f3SMichal Simek { return uart_zynq_serial_tstc(port); } \ 1546c4da359SMichal Simek static void uart_zynq##port##_putc(const char c) \ 155194846f3SMichal Simek { uart_zynq_serial_putc(c, port); } \ 1566c4da359SMichal Simek static void uart_zynq##port##_puts(const char *s) \ 157194846f3SMichal Simek { uart_zynq_serial_puts(s, port); } 158194846f3SMichal Simek 159194846f3SMichal Simek /* Serial device descriptor */ 160194846f3SMichal Simek #define INIT_PSSERIAL_STRUCTURE(port, __name) { \ 161194846f3SMichal Simek .name = __name, \ 16289143fb3SMarek Vasut .start = uart_zynq##port##_init, \ 16389143fb3SMarek Vasut .stop = NULL, \ 164194846f3SMichal Simek .setbrg = uart_zynq##port##_setbrg, \ 165194846f3SMichal Simek .getc = uart_zynq##port##_getc, \ 166194846f3SMichal Simek .tstc = uart_zynq##port##_tstc, \ 167194846f3SMichal Simek .putc = uart_zynq##port##_putc, \ 168194846f3SMichal Simek .puts = uart_zynq##port##_puts, \ 169194846f3SMichal Simek } 170194846f3SMichal Simek 171194846f3SMichal Simek DECLARE_PSSERIAL_FUNCTIONS(0); 1726c4da359SMichal Simek static struct serial_device uart_zynq_serial0_device = 173194846f3SMichal Simek INIT_PSSERIAL_STRUCTURE(0, "ttyPS0"); 174194846f3SMichal Simek DECLARE_PSSERIAL_FUNCTIONS(1); 1756c4da359SMichal Simek static struct serial_device uart_zynq_serial1_device = 176194846f3SMichal Simek INIT_PSSERIAL_STRUCTURE(1, "ttyPS1"); 177194846f3SMichal Simek 178c9416b92SMichal Simek #ifdef CONFIG_OF_CONTROL 179c9416b92SMichal Simek __weak struct serial_device *default_serial_console(void) 180c9416b92SMichal Simek { 181c9416b92SMichal Simek const void *blob = gd->fdt_blob; 182c9416b92SMichal Simek int node; 183c9416b92SMichal Simek unsigned int base_addr; 184c9416b92SMichal Simek 185c9416b92SMichal Simek node = fdt_path_offset(blob, "serial0"); 186c9416b92SMichal Simek if (node < 0) 187c9416b92SMichal Simek return NULL; 188c9416b92SMichal Simek 189c9416b92SMichal Simek base_addr = fdtdec_get_addr(blob, node, "reg"); 190c9416b92SMichal Simek if (base_addr == FDT_ADDR_T_NONE) 191c9416b92SMichal Simek return NULL; 192c9416b92SMichal Simek 193c9416b92SMichal Simek if (base_addr == ZYNQ_SERIAL_BASEADDR0) 194c9416b92SMichal Simek return &uart_zynq_serial0_device; 195c9416b92SMichal Simek 196c9416b92SMichal Simek if (base_addr == ZYNQ_SERIAL_BASEADDR1) 197c9416b92SMichal Simek return &uart_zynq_serial1_device; 198c9416b92SMichal Simek 199c9416b92SMichal Simek return NULL; 200c9416b92SMichal Simek } 201c9416b92SMichal Simek #else 202194846f3SMichal Simek __weak struct serial_device *default_serial_console(void) 203194846f3SMichal Simek { 204bf834950SMichal Simek #if defined(CONFIG_ZYNQ_SERIAL_UART0) 205194846f3SMichal Simek if (uart_zynq_ports[0]) 206194846f3SMichal Simek return &uart_zynq_serial0_device; 207bf834950SMichal Simek #endif 208bf834950SMichal Simek #if defined(CONFIG_ZYNQ_SERIAL_UART1) 209194846f3SMichal Simek if (uart_zynq_ports[1]) 210194846f3SMichal Simek return &uart_zynq_serial1_device; 211bf834950SMichal Simek #endif 212194846f3SMichal Simek return NULL; 213194846f3SMichal Simek } 214c9416b92SMichal Simek #endif 21551d8102fSTom Rini 216870e0bdaSMichal Simek void zynq_serial_initialize(void) 21751d8102fSTom Rini { 21851d8102fSTom Rini serial_register(&uart_zynq_serial0_device); 21951d8102fSTom Rini serial_register(&uart_zynq_serial1_device); 22051d8102fSTom Rini } 221