Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/drivers/char/amba.c |
| 3 | * |
| 4 | * Driver for AMBA serial ports |
| 5 | * |
| 6 | * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. |
| 7 | * |
| 8 | * Copyright 1999 ARM Limited |
| 9 | * Copyright (C) 2000 Deep Blue Solutions Ltd. |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or modify |
| 12 | * it under the terms of the GNU General Public License as published by |
| 13 | * the Free Software Foundation; either version 2 of the License, or |
| 14 | * (at your option) any later version. |
| 15 | * |
| 16 | * This program is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | * GNU General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License |
| 22 | * along with this program; if not, write to the Free Software |
| 23 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 24 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | * This is a generic driver for ARM AMBA-type serial ports. They |
| 26 | * have a lot of 16550-like features, but are not register compatible. |
| 27 | * Note that although they do have CTS, DCD and DSR inputs, they do |
| 28 | * not have an RI input, nor do they have DTR or RTS outputs. If |
| 29 | * required, these have to be supplied via some other means (eg, GPIO) |
| 30 | * and hooked into this driver. |
| 31 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | |
| 33 | #if defined(CONFIG_SERIAL_AMBA_PL011_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) |
| 34 | #define SUPPORT_SYSRQ |
| 35 | #endif |
| 36 | |
| 37 | #include <linux/module.h> |
| 38 | #include <linux/ioport.h> |
| 39 | #include <linux/init.h> |
| 40 | #include <linux/console.h> |
| 41 | #include <linux/sysrq.h> |
| 42 | #include <linux/device.h> |
| 43 | #include <linux/tty.h> |
| 44 | #include <linux/tty_flip.h> |
| 45 | #include <linux/serial_core.h> |
| 46 | #include <linux/serial.h> |
Russell King | a62c80e | 2006-01-07 13:52:45 +0000 | [diff] [blame] | 47 | #include <linux/amba/bus.h> |
| 48 | #include <linux/amba/serial.h> |
Russell King | f8ce254 | 2006-01-07 16:15:52 +0000 | [diff] [blame] | 49 | #include <linux/clk.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | |
| 51 | #include <asm/io.h> |
Russell King | c6b8fda | 2005-10-28 14:05:16 +0100 | [diff] [blame] | 52 | #include <asm/sizes.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | |
| 54 | #define UART_NR 14 |
| 55 | |
| 56 | #define SERIAL_AMBA_MAJOR 204 |
| 57 | #define SERIAL_AMBA_MINOR 64 |
| 58 | #define SERIAL_AMBA_NR UART_NR |
| 59 | |
| 60 | #define AMBA_ISR_PASS_LIMIT 256 |
| 61 | |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 62 | #define UART_DR_ERROR (UART011_DR_OE|UART011_DR_BE|UART011_DR_PE|UART011_DR_FE) |
| 63 | #define UART_DUMMY_DR_RX (1 << 16) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | |
| 65 | /* |
| 66 | * We wrap our port structure around the generic uart_port. |
| 67 | */ |
| 68 | struct uart_amba_port { |
| 69 | struct uart_port port; |
| 70 | struct clk *clk; |
| 71 | unsigned int im; /* interrupt mask */ |
| 72 | unsigned int old_status; |
| 73 | }; |
| 74 | |
Russell King | b129a8c | 2005-08-31 10:12:14 +0100 | [diff] [blame] | 75 | static void pl011_stop_tx(struct uart_port *port) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | { |
| 77 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 78 | |
| 79 | uap->im &= ~UART011_TXIM; |
| 80 | writew(uap->im, uap->port.membase + UART011_IMSC); |
| 81 | } |
| 82 | |
Russell King | b129a8c | 2005-08-31 10:12:14 +0100 | [diff] [blame] | 83 | static void pl011_start_tx(struct uart_port *port) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | { |
| 85 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 86 | |
| 87 | uap->im |= UART011_TXIM; |
| 88 | writew(uap->im, uap->port.membase + UART011_IMSC); |
| 89 | } |
| 90 | |
| 91 | static void pl011_stop_rx(struct uart_port *port) |
| 92 | { |
| 93 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 94 | |
| 95 | uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM| |
| 96 | UART011_PEIM|UART011_BEIM|UART011_OEIM); |
| 97 | writew(uap->im, uap->port.membase + UART011_IMSC); |
| 98 | } |
| 99 | |
| 100 | static void pl011_enable_ms(struct uart_port *port) |
| 101 | { |
| 102 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 103 | |
| 104 | uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM; |
| 105 | writew(uap->im, uap->port.membase + UART011_IMSC); |
| 106 | } |
| 107 | |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 108 | static void pl011_rx_chars(struct uart_amba_port *uap) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | { |
Takashi Iwai | a88487c | 2008-07-16 21:54:42 +0100 | [diff] [blame] | 110 | struct tty_struct *tty = uap->port.info->port.tty; |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 111 | unsigned int status, ch, flag, max_count = 256; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | |
| 113 | status = readw(uap->port.membase + UART01x_FR); |
| 114 | while ((status & UART01x_FR_RXFE) == 0 && max_count--) { |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 115 | ch = readw(uap->port.membase + UART01x_DR) | UART_DUMMY_DR_RX; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | flag = TTY_NORMAL; |
| 117 | uap->port.icount.rx++; |
| 118 | |
| 119 | /* |
| 120 | * Note that the error handling code is |
| 121 | * out of the main execution path |
| 122 | */ |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 123 | if (unlikely(ch & UART_DR_ERROR)) { |
| 124 | if (ch & UART011_DR_BE) { |
| 125 | ch &= ~(UART011_DR_FE | UART011_DR_PE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | uap->port.icount.brk++; |
| 127 | if (uart_handle_break(&uap->port)) |
| 128 | goto ignore_char; |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 129 | } else if (ch & UART011_DR_PE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | uap->port.icount.parity++; |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 131 | else if (ch & UART011_DR_FE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | uap->port.icount.frame++; |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 133 | if (ch & UART011_DR_OE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | uap->port.icount.overrun++; |
| 135 | |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 136 | ch &= uap->port.read_status_mask; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 138 | if (ch & UART011_DR_BE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | flag = TTY_BREAK; |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 140 | else if (ch & UART011_DR_PE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | flag = TTY_PARITY; |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 142 | else if (ch & UART011_DR_FE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | flag = TTY_FRAME; |
| 144 | } |
| 145 | |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 146 | if (uart_handle_sysrq_char(&uap->port, ch & 255)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 147 | goto ignore_char; |
| 148 | |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 149 | uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag); |
Russell King | 05ab301 | 2005-05-09 23:21:59 +0100 | [diff] [blame] | 150 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | ignore_char: |
| 152 | status = readw(uap->port.membase + UART01x_FR); |
| 153 | } |
Thomas Gleixner | 2389b27 | 2007-05-29 21:53:50 +0100 | [diff] [blame] | 154 | spin_unlock(&uap->port.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | tty_flip_buffer_push(tty); |
Thomas Gleixner | 2389b27 | 2007-05-29 21:53:50 +0100 | [diff] [blame] | 156 | spin_lock(&uap->port.lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | } |
| 158 | |
| 159 | static void pl011_tx_chars(struct uart_amba_port *uap) |
| 160 | { |
| 161 | struct circ_buf *xmit = &uap->port.info->xmit; |
| 162 | int count; |
| 163 | |
| 164 | if (uap->port.x_char) { |
| 165 | writew(uap->port.x_char, uap->port.membase + UART01x_DR); |
| 166 | uap->port.icount.tx++; |
| 167 | uap->port.x_char = 0; |
| 168 | return; |
| 169 | } |
| 170 | if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) { |
Russell King | b129a8c | 2005-08-31 10:12:14 +0100 | [diff] [blame] | 171 | pl011_stop_tx(&uap->port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | return; |
| 173 | } |
| 174 | |
| 175 | count = uap->port.fifosize >> 1; |
| 176 | do { |
| 177 | writew(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR); |
| 178 | xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); |
| 179 | uap->port.icount.tx++; |
| 180 | if (uart_circ_empty(xmit)) |
| 181 | break; |
| 182 | } while (--count > 0); |
| 183 | |
| 184 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) |
| 185 | uart_write_wakeup(&uap->port); |
| 186 | |
| 187 | if (uart_circ_empty(xmit)) |
Russell King | b129a8c | 2005-08-31 10:12:14 +0100 | [diff] [blame] | 188 | pl011_stop_tx(&uap->port); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | } |
| 190 | |
| 191 | static void pl011_modem_status(struct uart_amba_port *uap) |
| 192 | { |
| 193 | unsigned int status, delta; |
| 194 | |
| 195 | status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY; |
| 196 | |
| 197 | delta = status ^ uap->old_status; |
| 198 | uap->old_status = status; |
| 199 | |
| 200 | if (!delta) |
| 201 | return; |
| 202 | |
| 203 | if (delta & UART01x_FR_DCD) |
| 204 | uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD); |
| 205 | |
| 206 | if (delta & UART01x_FR_DSR) |
| 207 | uap->port.icount.dsr++; |
| 208 | |
| 209 | if (delta & UART01x_FR_CTS) |
| 210 | uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS); |
| 211 | |
| 212 | wake_up_interruptible(&uap->port.info->delta_msr_wait); |
| 213 | } |
| 214 | |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 215 | static irqreturn_t pl011_int(int irq, void *dev_id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | { |
| 217 | struct uart_amba_port *uap = dev_id; |
| 218 | unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT; |
| 219 | int handled = 0; |
| 220 | |
| 221 | spin_lock(&uap->port.lock); |
| 222 | |
| 223 | status = readw(uap->port.membase + UART011_MIS); |
| 224 | if (status) { |
| 225 | do { |
| 226 | writew(status & ~(UART011_TXIS|UART011_RTIS| |
| 227 | UART011_RXIS), |
| 228 | uap->port.membase + UART011_ICR); |
| 229 | |
| 230 | if (status & (UART011_RTIS|UART011_RXIS)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | pl011_rx_chars(uap); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | if (status & (UART011_DSRMIS|UART011_DCDMIS| |
| 233 | UART011_CTSMIS|UART011_RIMIS)) |
| 234 | pl011_modem_status(uap); |
| 235 | if (status & UART011_TXIS) |
| 236 | pl011_tx_chars(uap); |
| 237 | |
| 238 | if (pass_counter-- == 0) |
| 239 | break; |
| 240 | |
| 241 | status = readw(uap->port.membase + UART011_MIS); |
| 242 | } while (status != 0); |
| 243 | handled = 1; |
| 244 | } |
| 245 | |
| 246 | spin_unlock(&uap->port.lock); |
| 247 | |
| 248 | return IRQ_RETVAL(handled); |
| 249 | } |
| 250 | |
| 251 | static unsigned int pl01x_tx_empty(struct uart_port *port) |
| 252 | { |
| 253 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 254 | unsigned int status = readw(uap->port.membase + UART01x_FR); |
| 255 | return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT; |
| 256 | } |
| 257 | |
| 258 | static unsigned int pl01x_get_mctrl(struct uart_port *port) |
| 259 | { |
| 260 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 261 | unsigned int result = 0; |
| 262 | unsigned int status = readw(uap->port.membase + UART01x_FR); |
| 263 | |
Jiri Slaby | 5159f40 | 2007-10-18 23:40:31 -0700 | [diff] [blame] | 264 | #define TIOCMBIT(uartbit, tiocmbit) \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 265 | if (status & uartbit) \ |
| 266 | result |= tiocmbit |
| 267 | |
Jiri Slaby | 5159f40 | 2007-10-18 23:40:31 -0700 | [diff] [blame] | 268 | TIOCMBIT(UART01x_FR_DCD, TIOCM_CAR); |
| 269 | TIOCMBIT(UART01x_FR_DSR, TIOCM_DSR); |
| 270 | TIOCMBIT(UART01x_FR_CTS, TIOCM_CTS); |
| 271 | TIOCMBIT(UART011_FR_RI, TIOCM_RNG); |
| 272 | #undef TIOCMBIT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | return result; |
| 274 | } |
| 275 | |
| 276 | static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl) |
| 277 | { |
| 278 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 279 | unsigned int cr; |
| 280 | |
| 281 | cr = readw(uap->port.membase + UART011_CR); |
| 282 | |
Jiri Slaby | 5159f40 | 2007-10-18 23:40:31 -0700 | [diff] [blame] | 283 | #define TIOCMBIT(tiocmbit, uartbit) \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | if (mctrl & tiocmbit) \ |
| 285 | cr |= uartbit; \ |
| 286 | else \ |
| 287 | cr &= ~uartbit |
| 288 | |
Jiri Slaby | 5159f40 | 2007-10-18 23:40:31 -0700 | [diff] [blame] | 289 | TIOCMBIT(TIOCM_RTS, UART011_CR_RTS); |
| 290 | TIOCMBIT(TIOCM_DTR, UART011_CR_DTR); |
| 291 | TIOCMBIT(TIOCM_OUT1, UART011_CR_OUT1); |
| 292 | TIOCMBIT(TIOCM_OUT2, UART011_CR_OUT2); |
| 293 | TIOCMBIT(TIOCM_LOOP, UART011_CR_LBE); |
| 294 | #undef TIOCMBIT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 295 | |
| 296 | writew(cr, uap->port.membase + UART011_CR); |
| 297 | } |
| 298 | |
| 299 | static void pl011_break_ctl(struct uart_port *port, int break_state) |
| 300 | { |
| 301 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 302 | unsigned long flags; |
| 303 | unsigned int lcr_h; |
| 304 | |
| 305 | spin_lock_irqsave(&uap->port.lock, flags); |
| 306 | lcr_h = readw(uap->port.membase + UART011_LCRH); |
| 307 | if (break_state == -1) |
| 308 | lcr_h |= UART01x_LCRH_BRK; |
| 309 | else |
| 310 | lcr_h &= ~UART01x_LCRH_BRK; |
| 311 | writew(lcr_h, uap->port.membase + UART011_LCRH); |
| 312 | spin_unlock_irqrestore(&uap->port.lock, flags); |
| 313 | } |
| 314 | |
Jason Wessel | 84b5ae1 | 2008-02-20 13:33:39 -0600 | [diff] [blame] | 315 | #ifdef CONFIG_CONSOLE_POLL |
| 316 | static int pl010_get_poll_char(struct uart_port *port) |
| 317 | { |
| 318 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 319 | unsigned int status; |
| 320 | |
| 321 | do { |
| 322 | status = readw(uap->port.membase + UART01x_FR); |
| 323 | } while (status & UART01x_FR_RXFE); |
| 324 | |
| 325 | return readw(uap->port.membase + UART01x_DR); |
| 326 | } |
| 327 | |
| 328 | static void pl010_put_poll_char(struct uart_port *port, |
| 329 | unsigned char ch) |
| 330 | { |
| 331 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 332 | |
| 333 | while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF) |
| 334 | barrier(); |
| 335 | |
| 336 | writew(ch, uap->port.membase + UART01x_DR); |
| 337 | } |
| 338 | |
| 339 | #endif /* CONFIG_CONSOLE_POLL */ |
| 340 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | static int pl011_startup(struct uart_port *port) |
| 342 | { |
| 343 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 344 | unsigned int cr; |
| 345 | int retval; |
| 346 | |
| 347 | /* |
| 348 | * Try to enable the clock producer. |
| 349 | */ |
| 350 | retval = clk_enable(uap->clk); |
| 351 | if (retval) |
| 352 | goto out; |
| 353 | |
| 354 | uap->port.uartclk = clk_get_rate(uap->clk); |
| 355 | |
| 356 | /* |
| 357 | * Allocate the IRQ |
| 358 | */ |
| 359 | retval = request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap); |
| 360 | if (retval) |
| 361 | goto clk_dis; |
| 362 | |
| 363 | writew(UART011_IFLS_RX4_8|UART011_IFLS_TX4_8, |
| 364 | uap->port.membase + UART011_IFLS); |
| 365 | |
| 366 | /* |
| 367 | * Provoke TX FIFO interrupt into asserting. |
| 368 | */ |
| 369 | cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE; |
| 370 | writew(cr, uap->port.membase + UART011_CR); |
| 371 | writew(0, uap->port.membase + UART011_FBRD); |
| 372 | writew(1, uap->port.membase + UART011_IBRD); |
| 373 | writew(0, uap->port.membase + UART011_LCRH); |
| 374 | writew(0, uap->port.membase + UART01x_DR); |
| 375 | while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY) |
| 376 | barrier(); |
| 377 | |
| 378 | cr = UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE; |
| 379 | writew(cr, uap->port.membase + UART011_CR); |
| 380 | |
| 381 | /* |
| 382 | * initialise the old status of the modem signals |
| 383 | */ |
| 384 | uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY; |
| 385 | |
| 386 | /* |
| 387 | * Finally, enable interrupts |
| 388 | */ |
| 389 | spin_lock_irq(&uap->port.lock); |
| 390 | uap->im = UART011_RXIM | UART011_RTIM; |
| 391 | writew(uap->im, uap->port.membase + UART011_IMSC); |
| 392 | spin_unlock_irq(&uap->port.lock); |
| 393 | |
| 394 | return 0; |
| 395 | |
| 396 | clk_dis: |
| 397 | clk_disable(uap->clk); |
| 398 | out: |
| 399 | return retval; |
| 400 | } |
| 401 | |
| 402 | static void pl011_shutdown(struct uart_port *port) |
| 403 | { |
| 404 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
| 405 | unsigned long val; |
| 406 | |
| 407 | /* |
| 408 | * disable all interrupts |
| 409 | */ |
| 410 | spin_lock_irq(&uap->port.lock); |
| 411 | uap->im = 0; |
| 412 | writew(uap->im, uap->port.membase + UART011_IMSC); |
| 413 | writew(0xffff, uap->port.membase + UART011_ICR); |
| 414 | spin_unlock_irq(&uap->port.lock); |
| 415 | |
| 416 | /* |
| 417 | * Free the interrupt |
| 418 | */ |
| 419 | free_irq(uap->port.irq, uap); |
| 420 | |
| 421 | /* |
| 422 | * disable the port |
| 423 | */ |
| 424 | writew(UART01x_CR_UARTEN | UART011_CR_TXE, uap->port.membase + UART011_CR); |
| 425 | |
| 426 | /* |
| 427 | * disable break condition and fifos |
| 428 | */ |
| 429 | val = readw(uap->port.membase + UART011_LCRH); |
| 430 | val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN); |
| 431 | writew(val, uap->port.membase + UART011_LCRH); |
| 432 | |
| 433 | /* |
| 434 | * Shut down the clock producer |
| 435 | */ |
| 436 | clk_disable(uap->clk); |
| 437 | } |
| 438 | |
| 439 | static void |
Alan Cox | 606d099 | 2006-12-08 02:38:45 -0800 | [diff] [blame] | 440 | pl011_set_termios(struct uart_port *port, struct ktermios *termios, |
| 441 | struct ktermios *old) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 442 | { |
| 443 | unsigned int lcr_h, old_cr; |
| 444 | unsigned long flags; |
| 445 | unsigned int baud, quot; |
| 446 | |
| 447 | /* |
| 448 | * Ask the core to calculate the divisor for us. |
| 449 | */ |
| 450 | baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16); |
| 451 | quot = port->uartclk * 4 / baud; |
| 452 | |
| 453 | switch (termios->c_cflag & CSIZE) { |
| 454 | case CS5: |
| 455 | lcr_h = UART01x_LCRH_WLEN_5; |
| 456 | break; |
| 457 | case CS6: |
| 458 | lcr_h = UART01x_LCRH_WLEN_6; |
| 459 | break; |
| 460 | case CS7: |
| 461 | lcr_h = UART01x_LCRH_WLEN_7; |
| 462 | break; |
| 463 | default: // CS8 |
| 464 | lcr_h = UART01x_LCRH_WLEN_8; |
| 465 | break; |
| 466 | } |
| 467 | if (termios->c_cflag & CSTOPB) |
| 468 | lcr_h |= UART01x_LCRH_STP2; |
| 469 | if (termios->c_cflag & PARENB) { |
| 470 | lcr_h |= UART01x_LCRH_PEN; |
| 471 | if (!(termios->c_cflag & PARODD)) |
| 472 | lcr_h |= UART01x_LCRH_EPS; |
| 473 | } |
| 474 | if (port->fifosize > 1) |
| 475 | lcr_h |= UART01x_LCRH_FEN; |
| 476 | |
| 477 | spin_lock_irqsave(&port->lock, flags); |
| 478 | |
| 479 | /* |
| 480 | * Update the per-port timeout. |
| 481 | */ |
| 482 | uart_update_timeout(port, termios->c_cflag, baud); |
| 483 | |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 484 | port->read_status_mask = UART011_DR_OE | 255; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 485 | if (termios->c_iflag & INPCK) |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 486 | port->read_status_mask |= UART011_DR_FE | UART011_DR_PE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 487 | if (termios->c_iflag & (BRKINT | PARMRK)) |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 488 | port->read_status_mask |= UART011_DR_BE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 489 | |
| 490 | /* |
| 491 | * Characters to ignore |
| 492 | */ |
| 493 | port->ignore_status_mask = 0; |
| 494 | if (termios->c_iflag & IGNPAR) |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 495 | port->ignore_status_mask |= UART011_DR_FE | UART011_DR_PE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 496 | if (termios->c_iflag & IGNBRK) { |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 497 | port->ignore_status_mask |= UART011_DR_BE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | /* |
| 499 | * If we're ignoring parity and break indicators, |
| 500 | * ignore overruns too (for real raw support). |
| 501 | */ |
| 502 | if (termios->c_iflag & IGNPAR) |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 503 | port->ignore_status_mask |= UART011_DR_OE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 504 | } |
| 505 | |
| 506 | /* |
| 507 | * Ignore all characters if CREAD is not set. |
| 508 | */ |
| 509 | if ((termios->c_cflag & CREAD) == 0) |
Russell King | b63d4f0 | 2005-11-19 11:10:35 +0000 | [diff] [blame] | 510 | port->ignore_status_mask |= UART_DUMMY_DR_RX; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 511 | |
| 512 | if (UART_ENABLE_MS(port, termios->c_cflag)) |
| 513 | pl011_enable_ms(port); |
| 514 | |
| 515 | /* first, disable everything */ |
| 516 | old_cr = readw(port->membase + UART011_CR); |
| 517 | writew(0, port->membase + UART011_CR); |
| 518 | |
| 519 | /* Set baud rate */ |
| 520 | writew(quot & 0x3f, port->membase + UART011_FBRD); |
| 521 | writew(quot >> 6, port->membase + UART011_IBRD); |
| 522 | |
| 523 | /* |
| 524 | * ----------v----------v----------v----------v----- |
| 525 | * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L |
| 526 | * ----------^----------^----------^----------^----- |
| 527 | */ |
| 528 | writew(lcr_h, port->membase + UART011_LCRH); |
| 529 | writew(old_cr, port->membase + UART011_CR); |
| 530 | |
| 531 | spin_unlock_irqrestore(&port->lock, flags); |
| 532 | } |
| 533 | |
| 534 | static const char *pl011_type(struct uart_port *port) |
| 535 | { |
| 536 | return port->type == PORT_AMBA ? "AMBA/PL011" : NULL; |
| 537 | } |
| 538 | |
| 539 | /* |
| 540 | * Release the memory region(s) being used by 'port' |
| 541 | */ |
| 542 | static void pl010_release_port(struct uart_port *port) |
| 543 | { |
| 544 | release_mem_region(port->mapbase, SZ_4K); |
| 545 | } |
| 546 | |
| 547 | /* |
| 548 | * Request the memory region(s) being used by 'port' |
| 549 | */ |
| 550 | static int pl010_request_port(struct uart_port *port) |
| 551 | { |
| 552 | return request_mem_region(port->mapbase, SZ_4K, "uart-pl011") |
| 553 | != NULL ? 0 : -EBUSY; |
| 554 | } |
| 555 | |
| 556 | /* |
| 557 | * Configure/autoconfigure the port. |
| 558 | */ |
| 559 | static void pl010_config_port(struct uart_port *port, int flags) |
| 560 | { |
| 561 | if (flags & UART_CONFIG_TYPE) { |
| 562 | port->type = PORT_AMBA; |
| 563 | pl010_request_port(port); |
| 564 | } |
| 565 | } |
| 566 | |
| 567 | /* |
| 568 | * verify the new serial_struct (for TIOCSSERIAL). |
| 569 | */ |
| 570 | static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser) |
| 571 | { |
| 572 | int ret = 0; |
| 573 | if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA) |
| 574 | ret = -EINVAL; |
Yinghai Lu | a62c413 | 2008-08-19 20:49:55 -0700 | [diff] [blame] | 575 | if (ser->irq < 0 || ser->irq >= nr_irqs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 576 | ret = -EINVAL; |
| 577 | if (ser->baud_base < 9600) |
| 578 | ret = -EINVAL; |
| 579 | return ret; |
| 580 | } |
| 581 | |
| 582 | static struct uart_ops amba_pl011_pops = { |
| 583 | .tx_empty = pl01x_tx_empty, |
| 584 | .set_mctrl = pl011_set_mctrl, |
| 585 | .get_mctrl = pl01x_get_mctrl, |
| 586 | .stop_tx = pl011_stop_tx, |
| 587 | .start_tx = pl011_start_tx, |
| 588 | .stop_rx = pl011_stop_rx, |
| 589 | .enable_ms = pl011_enable_ms, |
| 590 | .break_ctl = pl011_break_ctl, |
| 591 | .startup = pl011_startup, |
| 592 | .shutdown = pl011_shutdown, |
| 593 | .set_termios = pl011_set_termios, |
| 594 | .type = pl011_type, |
| 595 | .release_port = pl010_release_port, |
| 596 | .request_port = pl010_request_port, |
| 597 | .config_port = pl010_config_port, |
| 598 | .verify_port = pl010_verify_port, |
Jason Wessel | 84b5ae1 | 2008-02-20 13:33:39 -0600 | [diff] [blame] | 599 | #ifdef CONFIG_CONSOLE_POLL |
| 600 | .poll_get_char = pl010_get_poll_char, |
| 601 | .poll_put_char = pl010_put_poll_char, |
| 602 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 603 | }; |
| 604 | |
| 605 | static struct uart_amba_port *amba_ports[UART_NR]; |
| 606 | |
| 607 | #ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE |
| 608 | |
Russell King | d358788 | 2006-03-20 20:00:09 +0000 | [diff] [blame] | 609 | static void pl011_console_putchar(struct uart_port *port, int ch) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 610 | { |
Russell King | d358788 | 2006-03-20 20:00:09 +0000 | [diff] [blame] | 611 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | |
Russell King | d358788 | 2006-03-20 20:00:09 +0000 | [diff] [blame] | 613 | while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF) |
| 614 | barrier(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | writew(ch, uap->port.membase + UART01x_DR); |
| 616 | } |
| 617 | |
| 618 | static void |
| 619 | pl011_console_write(struct console *co, const char *s, unsigned int count) |
| 620 | { |
| 621 | struct uart_amba_port *uap = amba_ports[co->index]; |
| 622 | unsigned int status, old_cr, new_cr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | |
| 624 | clk_enable(uap->clk); |
| 625 | |
| 626 | /* |
| 627 | * First save the CR then disable the interrupts |
| 628 | */ |
| 629 | old_cr = readw(uap->port.membase + UART011_CR); |
| 630 | new_cr = old_cr & ~UART011_CR_CTSEN; |
| 631 | new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE; |
| 632 | writew(new_cr, uap->port.membase + UART011_CR); |
| 633 | |
Russell King | d358788 | 2006-03-20 20:00:09 +0000 | [diff] [blame] | 634 | uart_console_write(&uap->port, s, count, pl011_console_putchar); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | |
| 636 | /* |
| 637 | * Finally, wait for transmitter to become empty |
| 638 | * and restore the TCR |
| 639 | */ |
| 640 | do { |
| 641 | status = readw(uap->port.membase + UART01x_FR); |
| 642 | } while (status & UART01x_FR_BUSY); |
| 643 | writew(old_cr, uap->port.membase + UART011_CR); |
| 644 | |
| 645 | clk_disable(uap->clk); |
| 646 | } |
| 647 | |
| 648 | static void __init |
| 649 | pl011_console_get_options(struct uart_amba_port *uap, int *baud, |
| 650 | int *parity, int *bits) |
| 651 | { |
| 652 | if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) { |
| 653 | unsigned int lcr_h, ibrd, fbrd; |
| 654 | |
| 655 | lcr_h = readw(uap->port.membase + UART011_LCRH); |
| 656 | |
| 657 | *parity = 'n'; |
| 658 | if (lcr_h & UART01x_LCRH_PEN) { |
| 659 | if (lcr_h & UART01x_LCRH_EPS) |
| 660 | *parity = 'e'; |
| 661 | else |
| 662 | *parity = 'o'; |
| 663 | } |
| 664 | |
| 665 | if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7) |
| 666 | *bits = 7; |
| 667 | else |
| 668 | *bits = 8; |
| 669 | |
| 670 | ibrd = readw(uap->port.membase + UART011_IBRD); |
| 671 | fbrd = readw(uap->port.membase + UART011_FBRD); |
| 672 | |
| 673 | *baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd); |
| 674 | } |
| 675 | } |
| 676 | |
| 677 | static int __init pl011_console_setup(struct console *co, char *options) |
| 678 | { |
| 679 | struct uart_amba_port *uap; |
| 680 | int baud = 38400; |
| 681 | int bits = 8; |
| 682 | int parity = 'n'; |
| 683 | int flow = 'n'; |
| 684 | |
| 685 | /* |
| 686 | * Check whether an invalid uart number has been specified, and |
| 687 | * if so, search for the first available port that does have |
| 688 | * console support. |
| 689 | */ |
| 690 | if (co->index >= UART_NR) |
| 691 | co->index = 0; |
| 692 | uap = amba_ports[co->index]; |
Russell King | d28122a | 2007-01-22 18:59:42 +0000 | [diff] [blame] | 693 | if (!uap) |
| 694 | return -ENODEV; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 695 | |
| 696 | uap->port.uartclk = clk_get_rate(uap->clk); |
| 697 | |
| 698 | if (options) |
| 699 | uart_parse_options(options, &baud, &parity, &bits, &flow); |
| 700 | else |
| 701 | pl011_console_get_options(uap, &baud, &parity, &bits); |
| 702 | |
| 703 | return uart_set_options(&uap->port, co, baud, parity, bits, flow); |
| 704 | } |
| 705 | |
Vincent Sanders | 2d93486 | 2005-09-14 22:36:03 +0100 | [diff] [blame] | 706 | static struct uart_driver amba_reg; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | static struct console amba_console = { |
| 708 | .name = "ttyAMA", |
| 709 | .write = pl011_console_write, |
| 710 | .device = uart_console_device, |
| 711 | .setup = pl011_console_setup, |
| 712 | .flags = CON_PRINTBUFFER, |
| 713 | .index = -1, |
| 714 | .data = &amba_reg, |
| 715 | }; |
| 716 | |
| 717 | #define AMBA_CONSOLE (&amba_console) |
| 718 | #else |
| 719 | #define AMBA_CONSOLE NULL |
| 720 | #endif |
| 721 | |
| 722 | static struct uart_driver amba_reg = { |
| 723 | .owner = THIS_MODULE, |
| 724 | .driver_name = "ttyAMA", |
| 725 | .dev_name = "ttyAMA", |
| 726 | .major = SERIAL_AMBA_MAJOR, |
| 727 | .minor = SERIAL_AMBA_MINOR, |
| 728 | .nr = UART_NR, |
| 729 | .cons = AMBA_CONSOLE, |
| 730 | }; |
| 731 | |
| 732 | static int pl011_probe(struct amba_device *dev, void *id) |
| 733 | { |
| 734 | struct uart_amba_port *uap; |
| 735 | void __iomem *base; |
| 736 | int i, ret; |
| 737 | |
| 738 | for (i = 0; i < ARRAY_SIZE(amba_ports); i++) |
| 739 | if (amba_ports[i] == NULL) |
| 740 | break; |
| 741 | |
| 742 | if (i == ARRAY_SIZE(amba_ports)) { |
| 743 | ret = -EBUSY; |
| 744 | goto out; |
| 745 | } |
| 746 | |
Yoann Padioleau | dd00cc4 | 2007-07-19 01:49:03 -0700 | [diff] [blame] | 747 | uap = kzalloc(sizeof(struct uart_amba_port), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 748 | if (uap == NULL) { |
| 749 | ret = -ENOMEM; |
| 750 | goto out; |
| 751 | } |
| 752 | |
| 753 | base = ioremap(dev->res.start, PAGE_SIZE); |
| 754 | if (!base) { |
| 755 | ret = -ENOMEM; |
| 756 | goto free; |
| 757 | } |
| 758 | |
Russell King | ee569c4 | 2008-11-30 17:38:14 +0000 | [diff] [blame] | 759 | uap->clk = clk_get(&dev->dev, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 760 | if (IS_ERR(uap->clk)) { |
| 761 | ret = PTR_ERR(uap->clk); |
| 762 | goto unmap; |
| 763 | } |
| 764 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 765 | uap->port.dev = &dev->dev; |
| 766 | uap->port.mapbase = dev->res.start; |
| 767 | uap->port.membase = base; |
| 768 | uap->port.iotype = UPIO_MEM; |
| 769 | uap->port.irq = dev->irq[0]; |
| 770 | uap->port.fifosize = 16; |
| 771 | uap->port.ops = &amba_pl011_pops; |
| 772 | uap->port.flags = UPF_BOOT_AUTOCONF; |
| 773 | uap->port.line = i; |
| 774 | |
| 775 | amba_ports[i] = uap; |
| 776 | |
| 777 | amba_set_drvdata(dev, uap); |
| 778 | ret = uart_add_one_port(&amba_reg, &uap->port); |
| 779 | if (ret) { |
| 780 | amba_set_drvdata(dev, NULL); |
| 781 | amba_ports[i] = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 782 | clk_put(uap->clk); |
| 783 | unmap: |
| 784 | iounmap(base); |
| 785 | free: |
| 786 | kfree(uap); |
| 787 | } |
| 788 | out: |
| 789 | return ret; |
| 790 | } |
| 791 | |
| 792 | static int pl011_remove(struct amba_device *dev) |
| 793 | { |
| 794 | struct uart_amba_port *uap = amba_get_drvdata(dev); |
| 795 | int i; |
| 796 | |
| 797 | amba_set_drvdata(dev, NULL); |
| 798 | |
| 799 | uart_remove_one_port(&amba_reg, &uap->port); |
| 800 | |
| 801 | for (i = 0; i < ARRAY_SIZE(amba_ports); i++) |
| 802 | if (amba_ports[i] == uap) |
| 803 | amba_ports[i] = NULL; |
| 804 | |
| 805 | iounmap(uap->port.membase); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 806 | clk_put(uap->clk); |
| 807 | kfree(uap); |
| 808 | return 0; |
| 809 | } |
| 810 | |
| 811 | static struct amba_id pl011_ids[] __initdata = { |
| 812 | { |
| 813 | .id = 0x00041011, |
| 814 | .mask = 0x000fffff, |
| 815 | }, |
| 816 | { 0, 0 }, |
| 817 | }; |
| 818 | |
| 819 | static struct amba_driver pl011_driver = { |
| 820 | .drv = { |
| 821 | .name = "uart-pl011", |
| 822 | }, |
| 823 | .id_table = pl011_ids, |
| 824 | .probe = pl011_probe, |
| 825 | .remove = pl011_remove, |
| 826 | }; |
| 827 | |
| 828 | static int __init pl011_init(void) |
| 829 | { |
| 830 | int ret; |
| 831 | printk(KERN_INFO "Serial: AMBA PL011 UART driver\n"); |
| 832 | |
| 833 | ret = uart_register_driver(&amba_reg); |
| 834 | if (ret == 0) { |
| 835 | ret = amba_driver_register(&pl011_driver); |
| 836 | if (ret) |
| 837 | uart_unregister_driver(&amba_reg); |
| 838 | } |
| 839 | return ret; |
| 840 | } |
| 841 | |
| 842 | static void __exit pl011_exit(void) |
| 843 | { |
| 844 | amba_driver_unregister(&pl011_driver); |
| 845 | uart_unregister_driver(&amba_reg); |
| 846 | } |
| 847 | |
| 848 | module_init(pl011_init); |
| 849 | module_exit(pl011_exit); |
| 850 | |
| 851 | MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd"); |
| 852 | MODULE_DESCRIPTION("ARM AMBA serial port driver"); |
| 853 | MODULE_LICENSE("GPL"); |