1 /* 2 * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com> 3 * 4 * (C) Copyright 2002 5 * Wolfgang Denk, DENX Software Engineering, <wd@denx.de> 6 * 7 * (C) Copyright 2002 8 * Sysgo Real-Time Solutions, GmbH <www.elinos.com> 9 * Marius Groeger <mgroeger@sysgo.de> 10 * 11 * (C) Copyright 2002 12 * Sysgo Real-Time Solutions, GmbH <www.elinos.com> 13 * Alex Zuepke <azu@sysgo.de> 14 * 15 * Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl) 16 * 17 * Modified to add driver model (DM) support 18 * (C) Copyright 2016 Marcel Ziswiler <marcel.ziswiler@toradex.com> 19 * 20 * SPDX-License-Identifier: GPL-2.0+ 21 */ 22 23 #include <common.h> 24 #include <asm/arch/pxa-regs.h> 25 #include <asm/arch/regs-uart.h> 26 #include <asm/io.h> 27 #include <dm.h> 28 #include <dm/platform_data/serial_pxa.h> 29 #include <linux/compiler.h> 30 #include <serial.h> 31 #include <watchdog.h> 32 33 DECLARE_GLOBAL_DATA_PTR; 34 35 static uint32_t pxa_uart_get_baud_divider(int baudrate) 36 { 37 return 921600 / baudrate; 38 } 39 40 static void pxa_uart_toggle_clock(uint32_t uart_index, int enable) 41 { 42 uint32_t clk_reg, clk_offset, reg; 43 44 clk_reg = UART_CLK_REG; 45 clk_offset = UART_CLK_BASE << uart_index; 46 47 reg = readl(clk_reg); 48 49 if (enable) 50 reg |= clk_offset; 51 else 52 reg &= ~clk_offset; 53 54 writel(reg, clk_reg); 55 } 56 57 /* 58 * Enable clock and set baud rate, parity etc. 59 */ 60 void pxa_setbrg_common(struct pxa_uart_regs *uart_regs, int port, int baudrate) 61 { 62 uint32_t divider = pxa_uart_get_baud_divider(baudrate); 63 if (!divider) 64 hang(); 65 66 67 pxa_uart_toggle_clock(port, 1); 68 69 /* Disable interrupts and FIFOs */ 70 writel(0, &uart_regs->ier); 71 writel(0, &uart_regs->fcr); 72 73 /* Set baud rate */ 74 writel(LCR_WLS0 | LCR_WLS1 | LCR_DLAB, &uart_regs->lcr); 75 writel(divider & 0xff, &uart_regs->dll); 76 writel(divider >> 8, &uart_regs->dlh); 77 writel(LCR_WLS0 | LCR_WLS1, &uart_regs->lcr); 78 79 /* Enable UART */ 80 writel(IER_UUE, &uart_regs->ier); 81 } 82 83 #ifndef CONFIG_DM_SERIAL 84 static struct pxa_uart_regs *pxa_uart_index_to_regs(uint32_t uart_index) 85 { 86 switch (uart_index) { 87 case FFUART_INDEX: return (struct pxa_uart_regs *)FFUART_BASE; 88 case BTUART_INDEX: return (struct pxa_uart_regs *)BTUART_BASE; 89 case STUART_INDEX: return (struct pxa_uart_regs *)STUART_BASE; 90 case HWUART_INDEX: return (struct pxa_uart_regs *)HWUART_BASE; 91 default: 92 return NULL; 93 } 94 } 95 96 /* 97 * Enable clock and set baud rate, parity etc. 98 */ 99 void pxa_setbrg_dev(uint32_t uart_index) 100 { 101 struct pxa_uart_regs *uart_regs = pxa_uart_index_to_regs(uart_index); 102 if (!uart_regs) 103 panic("Failed getting UART registers\n"); 104 105 pxa_setbrg_common(uart_regs, uart_index, gd->baudrate); 106 } 107 108 /* 109 * Initialise the serial port with the given baudrate. The settings 110 * are always 8 data bits, no parity, 1 stop bit, no start bits. 111 */ 112 int pxa_init_dev(unsigned int uart_index) 113 { 114 pxa_setbrg_dev(uart_index); 115 return 0; 116 } 117 118 /* 119 * Output a single byte to the serial port. 120 */ 121 void pxa_putc_dev(unsigned int uart_index, const char c) 122 { 123 struct pxa_uart_regs *uart_regs; 124 125 /* If \n, also do \r */ 126 if (c == '\n') 127 pxa_putc_dev(uart_index, '\r'); 128 129 uart_regs = pxa_uart_index_to_regs(uart_index); 130 if (!uart_regs) 131 hang(); 132 133 while (!(readl(&uart_regs->lsr) & LSR_TEMT)) 134 WATCHDOG_RESET(); 135 writel(c, &uart_regs->thr); 136 } 137 138 /* 139 * Read a single byte from the serial port. Returns 1 on success, 0 140 * otherwise. When the function is succesfull, the character read is 141 * written into its argument c. 142 */ 143 int pxa_tstc_dev(unsigned int uart_index) 144 { 145 struct pxa_uart_regs *uart_regs; 146 147 uart_regs = pxa_uart_index_to_regs(uart_index); 148 if (!uart_regs) 149 return -1; 150 151 return readl(&uart_regs->lsr) & LSR_DR; 152 } 153 154 /* 155 * Read a single byte from the serial port. Returns 1 on success, 0 156 * otherwise. When the function is succesfull, the character read is 157 * written into its argument c. 158 */ 159 int pxa_getc_dev(unsigned int uart_index) 160 { 161 struct pxa_uart_regs *uart_regs; 162 163 uart_regs = pxa_uart_index_to_regs(uart_index); 164 if (!uart_regs) 165 return -1; 166 167 while (!(readl(&uart_regs->lsr) & LSR_DR)) 168 WATCHDOG_RESET(); 169 return readl(&uart_regs->rbr) & 0xff; 170 } 171 172 void pxa_puts_dev(unsigned int uart_index, const char *s) 173 { 174 while (*s) 175 pxa_putc_dev(uart_index, *s++); 176 } 177 178 #define pxa_uart(uart, UART) \ 179 int uart##_init(void) \ 180 { \ 181 return pxa_init_dev(UART##_INDEX); \ 182 } \ 183 \ 184 void uart##_setbrg(void) \ 185 { \ 186 return pxa_setbrg_dev(UART##_INDEX); \ 187 } \ 188 \ 189 void uart##_putc(const char c) \ 190 { \ 191 return pxa_putc_dev(UART##_INDEX, c); \ 192 } \ 193 \ 194 void uart##_puts(const char *s) \ 195 { \ 196 return pxa_puts_dev(UART##_INDEX, s); \ 197 } \ 198 \ 199 int uart##_getc(void) \ 200 { \ 201 return pxa_getc_dev(UART##_INDEX); \ 202 } \ 203 \ 204 int uart##_tstc(void) \ 205 { \ 206 return pxa_tstc_dev(UART##_INDEX); \ 207 } \ 208 209 #define pxa_uart_desc(uart) \ 210 struct serial_device serial_##uart##_device = \ 211 { \ 212 .name = "serial_"#uart, \ 213 .start = uart##_init, \ 214 .stop = NULL, \ 215 .setbrg = uart##_setbrg, \ 216 .getc = uart##_getc, \ 217 .tstc = uart##_tstc, \ 218 .putc = uart##_putc, \ 219 .puts = uart##_puts, \ 220 }; 221 222 #define pxa_uart_multi(uart, UART) \ 223 pxa_uart(uart, UART) \ 224 pxa_uart_desc(uart) 225 226 #if defined(CONFIG_HWUART) 227 pxa_uart_multi(hwuart, HWUART) 228 #endif 229 #if defined(CONFIG_STUART) 230 pxa_uart_multi(stuart, STUART) 231 #endif 232 #if defined(CONFIG_FFUART) 233 pxa_uart_multi(ffuart, FFUART) 234 #endif 235 #if defined(CONFIG_BTUART) 236 pxa_uart_multi(btuart, BTUART) 237 #endif 238 239 __weak struct serial_device *default_serial_console(void) 240 { 241 #if CONFIG_CONS_INDEX == 1 242 return &serial_hwuart_device; 243 #elif CONFIG_CONS_INDEX == 2 244 return &serial_stuart_device; 245 #elif CONFIG_CONS_INDEX == 3 246 return &serial_ffuart_device; 247 #elif CONFIG_CONS_INDEX == 4 248 return &serial_btuart_device; 249 #else 250 #error "Bad CONFIG_CONS_INDEX." 251 #endif 252 } 253 254 void pxa_serial_initialize(void) 255 { 256 #if defined(CONFIG_FFUART) 257 serial_register(&serial_ffuart_device); 258 #endif 259 #if defined(CONFIG_BTUART) 260 serial_register(&serial_btuart_device); 261 #endif 262 #if defined(CONFIG_STUART) 263 serial_register(&serial_stuart_device); 264 #endif 265 } 266 #endif /* CONFIG_DM_SERIAL */ 267 268 #ifdef CONFIG_DM_SERIAL 269 static int pxa_serial_probe(struct udevice *dev) 270 { 271 struct pxa_serial_platdata *plat = dev->platdata; 272 273 pxa_setbrg_common((struct pxa_uart_regs *)plat->base, plat->port, 274 plat->baudrate); 275 return 0; 276 } 277 278 static int pxa_serial_putc(struct udevice *dev, const char ch) 279 { 280 struct pxa_serial_platdata *plat = dev->platdata; 281 struct pxa_uart_regs *uart_regs = (struct pxa_uart_regs *)plat->base; 282 283 /* Wait for last character to go. */ 284 if (!(readl(&uart_regs->lsr) & LSR_TEMT)) 285 return -EAGAIN; 286 287 writel(ch, &uart_regs->thr); 288 289 return 0; 290 } 291 292 static int pxa_serial_getc(struct udevice *dev) 293 { 294 struct pxa_serial_platdata *plat = dev->platdata; 295 struct pxa_uart_regs *uart_regs = (struct pxa_uart_regs *)plat->base; 296 297 /* Wait for a character to arrive. */ 298 if (!(readl(&uart_regs->lsr) & LSR_DR)) 299 return -EAGAIN; 300 301 return readl(&uart_regs->rbr) & 0xff; 302 } 303 304 int pxa_serial_setbrg(struct udevice *dev, int baudrate) 305 { 306 struct pxa_serial_platdata *plat = dev->platdata; 307 struct pxa_uart_regs *uart_regs = (struct pxa_uart_regs *)plat->base; 308 int port = plat->port; 309 310 pxa_setbrg_common(uart_regs, port, baudrate); 311 312 return 0; 313 } 314 315 static int pxa_serial_pending(struct udevice *dev, bool input) 316 { 317 struct pxa_serial_platdata *plat = dev->platdata; 318 struct pxa_uart_regs *uart_regs = (struct pxa_uart_regs *)plat->base; 319 320 if (input) 321 return readl(&uart_regs->lsr) & LSR_DR ? 1 : 0; 322 else 323 return readl(&uart_regs->lsr) & LSR_TEMT ? 0 : 1; 324 325 return 0; 326 } 327 328 static const struct dm_serial_ops pxa_serial_ops = { 329 .putc = pxa_serial_putc, 330 .pending = pxa_serial_pending, 331 .getc = pxa_serial_getc, 332 .setbrg = pxa_serial_setbrg, 333 }; 334 335 U_BOOT_DRIVER(serial_pxa) = { 336 .name = "serial_pxa", 337 .id = UCLASS_SERIAL, 338 .probe = pxa_serial_probe, 339 .ops = &pxa_serial_ops, 340 .flags = DM_FLAG_PRE_RELOC, 341 }; 342 #endif /* CONFIG_DM_SERIAL */ 343