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