1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (c) 2007 Sascha Hauer <s.hauer@pengutronix.de> 4 */ 5 6 #include <common.h> 7 #include <dm.h> 8 #include <errno.h> 9 #include <watchdog.h> 10 #include <asm/arch/imx-regs.h> 11 #include <asm/arch/clock.h> 12 #include <dm/platform_data/serial_mxc.h> 13 #include <serial.h> 14 #include <linux/compiler.h> 15 16 /* UART Control Register Bit Fields.*/ 17 #define URXD_CHARRDY (1<<15) 18 #define URXD_ERR (1<<14) 19 #define URXD_OVRRUN (1<<13) 20 #define URXD_FRMERR (1<<12) 21 #define URXD_BRK (1<<11) 22 #define URXD_PRERR (1<<10) 23 #define URXD_RX_DATA (0xFF) 24 #define UCR1_ADEN (1<<15) /* Auto dectect interrupt */ 25 #define UCR1_ADBR (1<<14) /* Auto detect baud rate */ 26 #define UCR1_TRDYEN (1<<13) /* Transmitter ready interrupt enable */ 27 #define UCR1_IDEN (1<<12) /* Idle condition interrupt */ 28 #define UCR1_RRDYEN (1<<9) /* Recv ready interrupt enable */ 29 #define UCR1_RDMAEN (1<<8) /* Recv ready DMA enable */ 30 #define UCR1_IREN (1<<7) /* Infrared interface enable */ 31 #define UCR1_TXMPTYEN (1<<6) /* Transimitter empty interrupt enable */ 32 #define UCR1_RTSDEN (1<<5) /* RTS delta interrupt enable */ 33 #define UCR1_SNDBRK (1<<4) /* Send break */ 34 #define UCR1_TDMAEN (1<<3) /* Transmitter ready DMA enable */ 35 #define UCR1_UARTCLKEN (1<<2) /* UART clock enabled */ 36 #define UCR1_DOZE (1<<1) /* Doze */ 37 #define UCR1_UARTEN (1<<0) /* UART enabled */ 38 #define UCR2_ESCI (1<<15) /* Escape seq interrupt enable */ 39 #define UCR2_IRTS (1<<14) /* Ignore RTS pin */ 40 #define UCR2_CTSC (1<<13) /* CTS pin control */ 41 #define UCR2_CTS (1<<12) /* Clear to send */ 42 #define UCR2_ESCEN (1<<11) /* Escape enable */ 43 #define UCR2_PREN (1<<8) /* Parity enable */ 44 #define UCR2_PROE (1<<7) /* Parity odd/even */ 45 #define UCR2_STPB (1<<6) /* Stop */ 46 #define UCR2_WS (1<<5) /* Word size */ 47 #define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */ 48 #define UCR2_TXEN (1<<2) /* Transmitter enabled */ 49 #define UCR2_RXEN (1<<1) /* Receiver enabled */ 50 #define UCR2_SRST (1<<0) /* SW reset */ 51 #define UCR3_DTREN (1<<13) /* DTR interrupt enable */ 52 #define UCR3_PARERREN (1<<12) /* Parity enable */ 53 #define UCR3_FRAERREN (1<<11) /* Frame error interrupt enable */ 54 #define UCR3_DSR (1<<10) /* Data set ready */ 55 #define UCR3_DCD (1<<9) /* Data carrier detect */ 56 #define UCR3_RI (1<<8) /* Ring indicator */ 57 #define UCR3_ADNIMP (1<<7) /* Autobaud Detection Not Improved */ 58 #define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */ 59 #define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */ 60 #define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */ 61 #define UCR3_REF25 (1<<3) /* Ref freq 25 MHz */ 62 #define UCR3_REF30 (1<<2) /* Ref Freq 30 MHz */ 63 #define UCR3_INVT (1<<1) /* Inverted Infrared transmission */ 64 #define UCR3_BPEN (1<<0) /* Preset registers enable */ 65 #define UCR4_CTSTL_32 (32<<10) /* CTS trigger level (32 chars) */ 66 #define UCR4_INVR (1<<9) /* Inverted infrared reception */ 67 #define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */ 68 #define UCR4_WKEN (1<<7) /* Wake interrupt enable */ 69 #define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */ 70 #define UCR4_IRSC (1<<5) /* IR special case */ 71 #define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */ 72 #define UCR4_BKEN (1<<2) /* Break condition interrupt enable */ 73 #define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */ 74 #define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */ 75 #define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */ 76 #define UFCR_RFDIV (7<<7) /* Reference freq divider mask */ 77 #define UFCR_RFDIV_SHF 7 /* Reference freq divider shift */ 78 #define RFDIV 4 /* divide input clock by 2 */ 79 #define UFCR_DCEDTE (1<<6) /* DTE mode select */ 80 #define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */ 81 #define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */ 82 #define USR1_RTSS (1<<14) /* RTS pin status */ 83 #define USR1_TRDY (1<<13) /* Transmitter ready interrupt/dma flag */ 84 #define USR1_RTSD (1<<12) /* RTS delta */ 85 #define USR1_ESCF (1<<11) /* Escape seq interrupt flag */ 86 #define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */ 87 #define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */ 88 #define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */ 89 #define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */ 90 #define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */ 91 #define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */ 92 #define USR2_ADET (1<<15) /* Auto baud rate detect complete */ 93 #define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */ 94 #define USR2_DTRF (1<<13) /* DTR edge interrupt flag */ 95 #define USR2_IDLE (1<<12) /* Idle condition */ 96 #define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */ 97 #define USR2_WAKE (1<<7) /* Wake */ 98 #define USR2_RTSF (1<<4) /* RTS edge interrupt flag */ 99 #define USR2_TXDC (1<<3) /* Transmitter complete */ 100 #define USR2_BRCD (1<<2) /* Break condition */ 101 #define USR2_ORE (1<<1) /* Overrun error */ 102 #define USR2_RDR (1<<0) /* Recv data ready */ 103 #define UTS_FRCPERR (1<<13) /* Force parity error */ 104 #define UTS_LOOP (1<<12) /* Loop tx and rx */ 105 #define UTS_TXEMPTY (1<<6) /* TxFIFO empty */ 106 #define UTS_RXEMPTY (1<<5) /* RxFIFO empty */ 107 #define UTS_TXFULL (1<<4) /* TxFIFO full */ 108 #define UTS_RXFULL (1<<3) /* RxFIFO full */ 109 #define UTS_SOFTRS (1<<0) /* Software reset */ 110 #define TXTL 2 /* reset default */ 111 #define RXTL 1 /* reset default */ 112 113 DECLARE_GLOBAL_DATA_PTR; 114 115 struct mxc_uart { 116 u32 rxd; 117 u32 spare0[15]; 118 119 u32 txd; 120 u32 spare1[15]; 121 122 u32 cr1; 123 u32 cr2; 124 u32 cr3; 125 u32 cr4; 126 127 u32 fcr; 128 u32 sr1; 129 u32 sr2; 130 u32 esc; 131 132 u32 tim; 133 u32 bir; 134 u32 bmr; 135 u32 brc; 136 137 u32 onems; 138 u32 ts; 139 }; 140 141 static void _mxc_serial_init(struct mxc_uart *base) 142 { 143 writel(0, &base->cr1); 144 writel(0, &base->cr2); 145 146 while (!(readl(&base->cr2) & UCR2_SRST)); 147 148 writel(0x704 | UCR3_ADNIMP, &base->cr3); 149 writel(0x8000, &base->cr4); 150 writel(0x2b, &base->esc); 151 writel(0, &base->tim); 152 153 writel(0, &base->ts); 154 } 155 156 static void _mxc_serial_setbrg(struct mxc_uart *base, unsigned long clk, 157 unsigned long baudrate, bool use_dte) 158 { 159 u32 tmp; 160 161 tmp = RFDIV << UFCR_RFDIV_SHF; 162 if (use_dte) 163 tmp |= UFCR_DCEDTE; 164 else 165 tmp |= (TXTL << UFCR_TXTL_SHF) | (RXTL << UFCR_RXTL_SHF); 166 writel(tmp, &base->fcr); 167 168 writel(0xf, &base->bir); 169 writel(clk / (2 * baudrate), &base->bmr); 170 171 writel(UCR2_WS | UCR2_IRTS | UCR2_RXEN | UCR2_TXEN | UCR2_SRST, 172 &base->cr2); 173 writel(UCR1_UARTEN, &base->cr1); 174 } 175 176 #ifndef CONFIG_DM_SERIAL 177 178 #ifndef CONFIG_MXC_UART_BASE 179 #error "define CONFIG_MXC_UART_BASE to use the MXC UART driver" 180 #endif 181 182 #define mxc_base ((struct mxc_uart *)CONFIG_MXC_UART_BASE) 183 184 static void mxc_serial_setbrg(void) 185 { 186 u32 clk = imx_get_uartclk(); 187 188 if (!gd->baudrate) 189 gd->baudrate = CONFIG_BAUDRATE; 190 191 _mxc_serial_setbrg(mxc_base, clk, gd->baudrate, false); 192 } 193 194 static int mxc_serial_getc(void) 195 { 196 while (readl(&mxc_base->ts) & UTS_RXEMPTY) 197 WATCHDOG_RESET(); 198 return (readl(&mxc_base->rxd) & URXD_RX_DATA); /* mask out status from upper word */ 199 } 200 201 static void mxc_serial_putc(const char c) 202 { 203 /* If \n, also do \r */ 204 if (c == '\n') 205 serial_putc('\r'); 206 207 writel(c, &mxc_base->txd); 208 209 /* wait for transmitter to be ready */ 210 while (!(readl(&mxc_base->ts) & UTS_TXEMPTY)) 211 WATCHDOG_RESET(); 212 } 213 214 /* Test whether a character is in the RX buffer */ 215 static int mxc_serial_tstc(void) 216 { 217 /* If receive fifo is empty, return false */ 218 if (readl(&mxc_base->ts) & UTS_RXEMPTY) 219 return 0; 220 return 1; 221 } 222 223 /* 224 * Initialise the serial port with the given baudrate. The settings 225 * are always 8 data bits, no parity, 1 stop bit, no start bits. 226 */ 227 static int mxc_serial_init(void) 228 { 229 _mxc_serial_init(mxc_base); 230 231 serial_setbrg(); 232 233 return 0; 234 } 235 236 static struct serial_device mxc_serial_drv = { 237 .name = "mxc_serial", 238 .start = mxc_serial_init, 239 .stop = NULL, 240 .setbrg = mxc_serial_setbrg, 241 .putc = mxc_serial_putc, 242 .puts = default_serial_puts, 243 .getc = mxc_serial_getc, 244 .tstc = mxc_serial_tstc, 245 }; 246 247 void mxc_serial_initialize(void) 248 { 249 serial_register(&mxc_serial_drv); 250 } 251 252 __weak struct serial_device *default_serial_console(void) 253 { 254 return &mxc_serial_drv; 255 } 256 #endif 257 258 #ifdef CONFIG_DM_SERIAL 259 260 int mxc_serial_setbrg(struct udevice *dev, int baudrate) 261 { 262 struct mxc_serial_platdata *plat = dev->platdata; 263 u32 clk = imx_get_uartclk(); 264 265 _mxc_serial_setbrg(plat->reg, clk, baudrate, plat->use_dte); 266 267 return 0; 268 } 269 270 static int mxc_serial_probe(struct udevice *dev) 271 { 272 struct mxc_serial_platdata *plat = dev->platdata; 273 274 _mxc_serial_init(plat->reg); 275 276 return 0; 277 } 278 279 static int mxc_serial_getc(struct udevice *dev) 280 { 281 struct mxc_serial_platdata *plat = dev->platdata; 282 struct mxc_uart *const uart = plat->reg; 283 284 if (readl(&uart->ts) & UTS_RXEMPTY) 285 return -EAGAIN; 286 287 return readl(&uart->rxd) & URXD_RX_DATA; 288 } 289 290 static int mxc_serial_putc(struct udevice *dev, const char ch) 291 { 292 struct mxc_serial_platdata *plat = dev->platdata; 293 struct mxc_uart *const uart = plat->reg; 294 295 if (!(readl(&uart->ts) & UTS_TXEMPTY)) 296 return -EAGAIN; 297 298 writel(ch, &uart->txd); 299 300 return 0; 301 } 302 303 static int mxc_serial_pending(struct udevice *dev, bool input) 304 { 305 struct mxc_serial_platdata *plat = dev->platdata; 306 struct mxc_uart *const uart = plat->reg; 307 uint32_t sr2 = readl(&uart->sr2); 308 309 if (input) 310 return sr2 & USR2_RDR ? 1 : 0; 311 else 312 return sr2 & USR2_TXDC ? 0 : 1; 313 } 314 315 static const struct dm_serial_ops mxc_serial_ops = { 316 .putc = mxc_serial_putc, 317 .pending = mxc_serial_pending, 318 .getc = mxc_serial_getc, 319 .setbrg = mxc_serial_setbrg, 320 }; 321 322 #if CONFIG_IS_ENABLED(OF_CONTROL) 323 static int mxc_serial_ofdata_to_platdata(struct udevice *dev) 324 { 325 struct mxc_serial_platdata *plat = dev->platdata; 326 fdt_addr_t addr; 327 328 addr = devfdt_get_addr(dev); 329 if (addr == FDT_ADDR_T_NONE) 330 return -EINVAL; 331 332 plat->reg = (struct mxc_uart *)addr; 333 334 plat->use_dte = fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev), 335 "fsl,dte-mode"); 336 return 0; 337 } 338 339 static const struct udevice_id mxc_serial_ids[] = { 340 { .compatible = "fsl,imx6ul-uart" }, 341 { .compatible = "fsl,imx7d-uart" }, 342 { } 343 }; 344 #endif 345 346 U_BOOT_DRIVER(serial_mxc) = { 347 .name = "serial_mxc", 348 .id = UCLASS_SERIAL, 349 #if CONFIG_IS_ENABLED(OF_CONTROL) 350 .of_match = mxc_serial_ids, 351 .ofdata_to_platdata = mxc_serial_ofdata_to_platdata, 352 .platdata_auto_alloc_size = sizeof(struct mxc_serial_platdata), 353 #endif 354 .probe = mxc_serial_probe, 355 .ops = &mxc_serial_ops, 356 .flags = DM_FLAG_PRE_RELOC, 357 }; 358 #endif 359 360 #ifdef CONFIG_DEBUG_UART_MXC 361 #include <debug_uart.h> 362 363 static inline void _debug_uart_init(void) 364 { 365 struct mxc_uart *base = (struct mxc_uart *)CONFIG_DEBUG_UART_BASE; 366 367 _mxc_serial_init(base); 368 _mxc_serial_setbrg(base, CONFIG_DEBUG_UART_CLOCK, 369 CONFIG_BAUDRATE, false); 370 } 371 372 static inline void _debug_uart_putc(int ch) 373 { 374 struct mxc_uart *base = (struct mxc_uart *)CONFIG_DEBUG_UART_BASE; 375 376 while (!(readl(&base->ts) & UTS_TXEMPTY)) 377 WATCHDOG_RESET(); 378 379 writel(ch, &base->txd); 380 } 381 382 DEBUG_UART_FUNCS 383 384 #endif 385