Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1 | /* |
| 2 | * 8250-core based driver for the OMAP internal UART |
| 3 | * |
| 4 | * based on omap-serial.c, Copyright (C) 2010 Texas Instruments. |
| 5 | * |
| 6 | * Copyright (C) 2014 Sebastian Andrzej Siewior |
| 7 | * |
| 8 | */ |
| 9 | |
| 10 | #include <linux/device.h> |
| 11 | #include <linux/io.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/serial_8250.h> |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 14 | #include <linux/serial_reg.h> |
Sebastian Andrzej Siewior | 7728524 | 2014-09-29 20:06:48 +0200 | [diff] [blame] | 15 | #include <linux/tty_flip.h> |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 16 | #include <linux/platform_device.h> |
| 17 | #include <linux/slab.h> |
| 18 | #include <linux/of.h> |
Sekhar Nori | 4fcdff9 | 2015-07-14 13:32:06 +0530 | [diff] [blame] | 19 | #include <linux/of_device.h> |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 20 | #include <linux/of_gpio.h> |
| 21 | #include <linux/of_irq.h> |
| 22 | #include <linux/delay.h> |
| 23 | #include <linux/pm_runtime.h> |
| 24 | #include <linux/console.h> |
| 25 | #include <linux/pm_qos.h> |
Tony Lindgren | a3e362f | 2015-06-09 23:35:00 -0700 | [diff] [blame] | 26 | #include <linux/pm_wakeirq.h> |
Sebastian Andrzej Siewior | 31a1713 | 2014-09-29 20:06:43 +0200 | [diff] [blame] | 27 | #include <linux/dma-mapping.h> |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 28 | |
| 29 | #include "8250.h" |
| 30 | |
| 31 | #define DEFAULT_CLK_SPEED 48000000 |
| 32 | |
| 33 | #define UART_ERRATA_i202_MDR1_ACCESS (1 << 0) |
| 34 | #define OMAP_UART_WER_HAS_TX_WAKEUP (1 << 1) |
Sebastian Andrzej Siewior | 31a1713 | 2014-09-29 20:06:43 +0200 | [diff] [blame] | 35 | #define OMAP_DMA_TX_KICK (1 << 2) |
Sekhar Nori | cdb929e | 2015-07-14 13:32:07 +0530 | [diff] [blame] | 36 | /* |
| 37 | * See Advisory 21 in AM437x errata SPRZ408B, updated April 2015. |
| 38 | * The same errata is applicable to AM335x and DRA7x processors too. |
| 39 | */ |
| 40 | #define UART_ERRATA_CLOCK_DISABLE (1 << 3) |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 41 | |
| 42 | #define OMAP_UART_FCR_RX_TRIG 6 |
| 43 | #define OMAP_UART_FCR_TX_TRIG 4 |
| 44 | |
| 45 | /* SCR register bitmasks */ |
| 46 | #define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK (1 << 7) |
| 47 | #define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK (1 << 6) |
| 48 | #define OMAP_UART_SCR_TX_EMPTY (1 << 3) |
| 49 | #define OMAP_UART_SCR_DMAMODE_MASK (3 << 1) |
| 50 | #define OMAP_UART_SCR_DMAMODE_1 (1 << 1) |
| 51 | #define OMAP_UART_SCR_DMAMODE_CTL (1 << 0) |
| 52 | |
| 53 | /* MVR register bitmasks */ |
| 54 | #define OMAP_UART_MVR_SCHEME_SHIFT 30 |
| 55 | #define OMAP_UART_LEGACY_MVR_MAJ_MASK 0xf0 |
| 56 | #define OMAP_UART_LEGACY_MVR_MAJ_SHIFT 4 |
| 57 | #define OMAP_UART_LEGACY_MVR_MIN_MASK 0x0f |
| 58 | #define OMAP_UART_MVR_MAJ_MASK 0x700 |
| 59 | #define OMAP_UART_MVR_MAJ_SHIFT 8 |
| 60 | #define OMAP_UART_MVR_MIN_MASK 0x3f |
| 61 | |
Sekhar Nori | cdb929e | 2015-07-14 13:32:07 +0530 | [diff] [blame] | 62 | /* SYSC register bitmasks */ |
| 63 | #define OMAP_UART_SYSC_SOFTRESET (1 << 1) |
| 64 | |
| 65 | /* SYSS register bitmasks */ |
| 66 | #define OMAP_UART_SYSS_RESETDONE (1 << 0) |
| 67 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 68 | #define UART_TI752_TLR_TX 0 |
| 69 | #define UART_TI752_TLR_RX 4 |
| 70 | |
| 71 | #define TRIGGER_TLR_MASK(x) ((x & 0x3c) >> 2) |
| 72 | #define TRIGGER_FCR_MASK(x) (x & 3) |
| 73 | |
| 74 | /* Enable XON/XOFF flow control on output */ |
| 75 | #define OMAP_UART_SW_TX 0x08 |
| 76 | /* Enable XON/XOFF flow control on input */ |
| 77 | #define OMAP_UART_SW_RX 0x02 |
| 78 | |
| 79 | #define OMAP_UART_WER_MOD_WKUP 0x7f |
| 80 | #define OMAP_UART_TX_WAKEUP_EN (1 << 7) |
| 81 | |
| 82 | #define TX_TRIGGER 1 |
| 83 | #define RX_TRIGGER 48 |
| 84 | |
| 85 | #define OMAP_UART_TCR_RESTORE(x) ((x / 4) << 4) |
| 86 | #define OMAP_UART_TCR_HALT(x) ((x / 4) << 0) |
| 87 | |
| 88 | #define UART_BUILD_REVISION(x, y) (((x) << 8) | (y)) |
| 89 | |
| 90 | #define OMAP_UART_REV_46 0x0406 |
| 91 | #define OMAP_UART_REV_52 0x0502 |
| 92 | #define OMAP_UART_REV_63 0x0603 |
| 93 | |
| 94 | struct omap8250_priv { |
| 95 | int line; |
| 96 | u8 habit; |
| 97 | u8 mdr1; |
| 98 | u8 efr; |
| 99 | u8 scr; |
| 100 | u8 wer; |
| 101 | u8 xon; |
| 102 | u8 xoff; |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 103 | u8 delayed_restore; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 104 | u16 quot; |
| 105 | |
| 106 | bool is_suspending; |
| 107 | int wakeirq; |
| 108 | int wakeups_enabled; |
| 109 | u32 latency; |
| 110 | u32 calc_latency; |
| 111 | struct pm_qos_request pm_qos_request; |
| 112 | struct work_struct qos_work; |
| 113 | struct uart_8250_dma omap8250_dma; |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 114 | spinlock_t rx_dma_lock; |
Sebastian Andrzej Siewior | 830acf9 | 2015-08-14 17:52:07 +0200 | [diff] [blame] | 115 | bool rx_dma_broken; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 116 | }; |
| 117 | |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 118 | #ifdef CONFIG_SERIAL_8250_DMA |
| 119 | static void omap_8250_rx_dma_flush(struct uart_8250_port *p); |
| 120 | #else |
| 121 | static inline void omap_8250_rx_dma_flush(struct uart_8250_port *p) { } |
| 122 | #endif |
| 123 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 124 | static u32 uart_read(struct uart_8250_port *up, u32 reg) |
| 125 | { |
| 126 | return readl(up->port.membase + (reg << up->port.regshift)); |
| 127 | } |
| 128 | |
Peter Hurley | 4bf4ea9 | 2014-12-30 20:28:15 -0500 | [diff] [blame] | 129 | static void omap8250_set_mctrl(struct uart_port *port, unsigned int mctrl) |
| 130 | { |
| 131 | struct uart_8250_port *up = up_to_u8250p(port); |
| 132 | struct omap8250_priv *priv = up->port.private_data; |
| 133 | u8 lcr; |
| 134 | |
| 135 | serial8250_do_set_mctrl(port, mctrl); |
| 136 | |
Andy Shevchenko | 5db4f7f | 2016-08-16 15:06:54 +0300 | [diff] [blame] | 137 | /* |
| 138 | * Turn off autoRTS if RTS is lowered and restore autoRTS setting |
| 139 | * if RTS is raised |
| 140 | */ |
| 141 | lcr = serial_in(up, UART_LCR); |
| 142 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
| 143 | if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS)) |
| 144 | priv->efr |= UART_EFR_RTS; |
| 145 | else |
| 146 | priv->efr &= ~UART_EFR_RTS; |
| 147 | serial_out(up, UART_EFR, priv->efr); |
| 148 | serial_out(up, UART_LCR, lcr); |
Peter Hurley | 4bf4ea9 | 2014-12-30 20:28:15 -0500 | [diff] [blame] | 149 | } |
| 150 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 151 | /* |
| 152 | * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460) |
| 153 | * The access to uart register after MDR1 Access |
| 154 | * causes UART to corrupt data. |
| 155 | * |
| 156 | * Need a delay = |
| 157 | * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS) |
| 158 | * give 10 times as much |
| 159 | */ |
| 160 | static void omap_8250_mdr1_errataset(struct uart_8250_port *up, |
| 161 | struct omap8250_priv *priv) |
| 162 | { |
| 163 | u8 timeout = 255; |
| 164 | u8 old_mdr1; |
| 165 | |
| 166 | old_mdr1 = serial_in(up, UART_OMAP_MDR1); |
| 167 | if (old_mdr1 == priv->mdr1) |
| 168 | return; |
| 169 | |
| 170 | serial_out(up, UART_OMAP_MDR1, priv->mdr1); |
| 171 | udelay(2); |
| 172 | serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT | |
| 173 | UART_FCR_CLEAR_RCVR); |
| 174 | /* |
| 175 | * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and |
| 176 | * TX_FIFO_E bit is 1. |
| 177 | */ |
| 178 | while (UART_LSR_THRE != (serial_in(up, UART_LSR) & |
| 179 | (UART_LSR_THRE | UART_LSR_DR))) { |
| 180 | timeout--; |
| 181 | if (!timeout) { |
| 182 | /* Should *never* happen. we warn and carry on */ |
| 183 | dev_crit(up->port.dev, "Errata i202: timedout %x\n", |
| 184 | serial_in(up, UART_LSR)); |
| 185 | break; |
| 186 | } |
| 187 | udelay(1); |
| 188 | } |
| 189 | } |
| 190 | |
| 191 | static void omap_8250_get_divisor(struct uart_port *port, unsigned int baud, |
| 192 | struct omap8250_priv *priv) |
| 193 | { |
| 194 | unsigned int uartclk = port->uartclk; |
| 195 | unsigned int div_13, div_16; |
| 196 | unsigned int abs_d13, abs_d16; |
| 197 | |
| 198 | /* |
| 199 | * Old custom speed handling. |
| 200 | */ |
| 201 | if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST) { |
| 202 | priv->quot = port->custom_divisor & 0xffff; |
| 203 | /* |
| 204 | * I assume that nobody is using this. But hey, if somebody |
| 205 | * would like to specify the divisor _and_ the mode then the |
| 206 | * driver is ready and waiting for it. |
| 207 | */ |
| 208 | if (port->custom_divisor & (1 << 16)) |
| 209 | priv->mdr1 = UART_OMAP_MDR1_13X_MODE; |
| 210 | else |
| 211 | priv->mdr1 = UART_OMAP_MDR1_16X_MODE; |
| 212 | return; |
| 213 | } |
| 214 | div_13 = DIV_ROUND_CLOSEST(uartclk, 13 * baud); |
| 215 | div_16 = DIV_ROUND_CLOSEST(uartclk, 16 * baud); |
| 216 | |
| 217 | if (!div_13) |
| 218 | div_13 = 1; |
| 219 | if (!div_16) |
| 220 | div_16 = 1; |
| 221 | |
| 222 | abs_d13 = abs(baud - uartclk / 13 / div_13); |
| 223 | abs_d16 = abs(baud - uartclk / 16 / div_16); |
| 224 | |
| 225 | if (abs_d13 >= abs_d16) { |
| 226 | priv->mdr1 = UART_OMAP_MDR1_16X_MODE; |
| 227 | priv->quot = div_16; |
| 228 | } else { |
| 229 | priv->mdr1 = UART_OMAP_MDR1_13X_MODE; |
| 230 | priv->quot = div_13; |
| 231 | } |
| 232 | } |
| 233 | |
| 234 | static void omap8250_update_scr(struct uart_8250_port *up, |
| 235 | struct omap8250_priv *priv) |
| 236 | { |
| 237 | u8 old_scr; |
| 238 | |
| 239 | old_scr = serial_in(up, UART_OMAP_SCR); |
| 240 | if (old_scr == priv->scr) |
| 241 | return; |
| 242 | |
| 243 | /* |
| 244 | * The manual recommends not to enable the DMA mode selector in the SCR |
| 245 | * (instead of the FCR) register _and_ selecting the DMA mode as one |
| 246 | * register write because this may lead to malfunction. |
| 247 | */ |
| 248 | if (priv->scr & OMAP_UART_SCR_DMAMODE_MASK) |
| 249 | serial_out(up, UART_OMAP_SCR, |
| 250 | priv->scr & ~OMAP_UART_SCR_DMAMODE_MASK); |
| 251 | serial_out(up, UART_OMAP_SCR, priv->scr); |
| 252 | } |
| 253 | |
Sekhar Nori | 6f03541 | 2015-07-14 13:32:05 +0530 | [diff] [blame] | 254 | static void omap8250_update_mdr1(struct uart_8250_port *up, |
| 255 | struct omap8250_priv *priv) |
| 256 | { |
| 257 | if (priv->habit & UART_ERRATA_i202_MDR1_ACCESS) |
| 258 | omap_8250_mdr1_errataset(up, priv); |
| 259 | else |
| 260 | serial_out(up, UART_OMAP_MDR1, priv->mdr1); |
| 261 | } |
| 262 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 263 | static void omap8250_restore_regs(struct uart_8250_port *up) |
| 264 | { |
| 265 | struct omap8250_priv *priv = up->port.private_data; |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 266 | struct uart_8250_dma *dma = up->dma; |
| 267 | |
| 268 | if (dma && dma->tx_running) { |
| 269 | /* |
| 270 | * TCSANOW requests the change to occur immediately however if |
| 271 | * we have a TX-DMA operation in progress then it has been |
| 272 | * observed that it might stall and never complete. Therefore we |
| 273 | * delay DMA completes to prevent this hang from happen. |
| 274 | */ |
| 275 | priv->delayed_restore = 1; |
| 276 | return; |
| 277 | } |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 278 | |
| 279 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
| 280 | serial_out(up, UART_EFR, UART_EFR_ECB); |
| 281 | |
| 282 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); |
Yegor Yefremov | 36fd95b | 2016-05-31 10:59:15 +0200 | [diff] [blame] | 283 | serial8250_out_MCR(up, UART_MCR_TCRTLR); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 284 | serial_out(up, UART_FCR, up->fcr); |
| 285 | |
| 286 | omap8250_update_scr(up, priv); |
| 287 | |
| 288 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
| 289 | |
| 290 | serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_RESTORE(16) | |
| 291 | OMAP_UART_TCR_HALT(52)); |
| 292 | serial_out(up, UART_TI752_TLR, |
| 293 | TRIGGER_TLR_MASK(TX_TRIGGER) << UART_TI752_TLR_TX | |
| 294 | TRIGGER_TLR_MASK(RX_TRIGGER) << UART_TI752_TLR_RX); |
| 295 | |
| 296 | serial_out(up, UART_LCR, 0); |
| 297 | |
| 298 | /* drop TCR + TLR access, we setup XON/XOFF later */ |
Yegor Yefremov | 36fd95b | 2016-05-31 10:59:15 +0200 | [diff] [blame] | 299 | serial8250_out_MCR(up, up->mcr); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 300 | serial_out(up, UART_IER, up->ier); |
| 301 | |
| 302 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
| 303 | serial_dl_write(up, priv->quot); |
| 304 | |
Peter Hurley | 9719acc | 2015-01-25 14:44:52 -0500 | [diff] [blame] | 305 | serial_out(up, UART_EFR, priv->efr); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 306 | |
| 307 | /* Configure flow control */ |
| 308 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
| 309 | serial_out(up, UART_XON1, priv->xon); |
| 310 | serial_out(up, UART_XOFF1, priv->xoff); |
| 311 | |
| 312 | serial_out(up, UART_LCR, up->lcr); |
Sekhar Nori | 6f03541 | 2015-07-14 13:32:05 +0530 | [diff] [blame] | 313 | |
| 314 | omap8250_update_mdr1(up, priv); |
| 315 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 316 | up->port.ops->set_mctrl(&up->port, up->port.mctrl); |
| 317 | } |
| 318 | |
| 319 | /* |
| 320 | * OMAP can use "CLK / (16 or 13) / div" for baud rate. And then we have have |
| 321 | * some differences in how we want to handle flow control. |
| 322 | */ |
| 323 | static void omap_8250_set_termios(struct uart_port *port, |
| 324 | struct ktermios *termios, |
| 325 | struct ktermios *old) |
| 326 | { |
Andy Shevchenko | 013e358 | 2016-02-18 21:22:59 +0200 | [diff] [blame] | 327 | struct uart_8250_port *up = up_to_u8250p(port); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 328 | struct omap8250_priv *priv = up->port.private_data; |
| 329 | unsigned char cval = 0; |
| 330 | unsigned int baud; |
| 331 | |
| 332 | switch (termios->c_cflag & CSIZE) { |
| 333 | case CS5: |
| 334 | cval = UART_LCR_WLEN5; |
| 335 | break; |
| 336 | case CS6: |
| 337 | cval = UART_LCR_WLEN6; |
| 338 | break; |
| 339 | case CS7: |
| 340 | cval = UART_LCR_WLEN7; |
| 341 | break; |
| 342 | default: |
| 343 | case CS8: |
| 344 | cval = UART_LCR_WLEN8; |
| 345 | break; |
| 346 | } |
| 347 | |
| 348 | if (termios->c_cflag & CSTOPB) |
| 349 | cval |= UART_LCR_STOP; |
| 350 | if (termios->c_cflag & PARENB) |
| 351 | cval |= UART_LCR_PARITY; |
| 352 | if (!(termios->c_cflag & PARODD)) |
| 353 | cval |= UART_LCR_EPAR; |
| 354 | if (termios->c_cflag & CMSPAR) |
| 355 | cval |= UART_LCR_SPAR; |
| 356 | |
| 357 | /* |
| 358 | * Ask the core to calculate the divisor for us. |
| 359 | */ |
| 360 | baud = uart_get_baud_rate(port, termios, old, |
| 361 | port->uartclk / 16 / 0xffff, |
| 362 | port->uartclk / 13); |
| 363 | omap_8250_get_divisor(port, baud, priv); |
| 364 | |
| 365 | /* |
| 366 | * Ok, we're now changing the port state. Do it with |
| 367 | * interrupts disabled. |
| 368 | */ |
| 369 | pm_runtime_get_sync(port->dev); |
| 370 | spin_lock_irq(&port->lock); |
| 371 | |
| 372 | /* |
| 373 | * Update the per-port timeout. |
| 374 | */ |
| 375 | uart_update_timeout(port, termios->c_cflag, baud); |
| 376 | |
| 377 | up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; |
| 378 | if (termios->c_iflag & INPCK) |
| 379 | up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE; |
| 380 | if (termios->c_iflag & (IGNBRK | PARMRK)) |
| 381 | up->port.read_status_mask |= UART_LSR_BI; |
| 382 | |
| 383 | /* |
| 384 | * Characters to ignore |
| 385 | */ |
| 386 | up->port.ignore_status_mask = 0; |
| 387 | if (termios->c_iflag & IGNPAR) |
| 388 | up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; |
| 389 | if (termios->c_iflag & IGNBRK) { |
| 390 | up->port.ignore_status_mask |= UART_LSR_BI; |
| 391 | /* |
| 392 | * If we're ignoring parity and break indicators, |
| 393 | * ignore overruns too (for real raw support). |
| 394 | */ |
| 395 | if (termios->c_iflag & IGNPAR) |
| 396 | up->port.ignore_status_mask |= UART_LSR_OE; |
| 397 | } |
| 398 | |
| 399 | /* |
| 400 | * ignore all characters if CREAD is not set |
| 401 | */ |
| 402 | if ((termios->c_cflag & CREAD) == 0) |
| 403 | up->port.ignore_status_mask |= UART_LSR_DR; |
| 404 | |
| 405 | /* |
| 406 | * Modem status interrupts |
| 407 | */ |
| 408 | up->ier &= ~UART_IER_MSI; |
| 409 | if (UART_ENABLE_MS(&up->port, termios->c_cflag)) |
| 410 | up->ier |= UART_IER_MSI; |
| 411 | |
| 412 | up->lcr = cval; |
| 413 | /* Up to here it was mostly serial8250_do_set_termios() */ |
| 414 | |
| 415 | /* |
| 416 | * We enable TRIG_GRANU for RX and TX and additionaly we set |
| 417 | * SCR_TX_EMPTY bit. The result is the following: |
| 418 | * - RX_TRIGGER amount of bytes in the FIFO will cause an interrupt. |
| 419 | * - less than RX_TRIGGER number of bytes will also cause an interrupt |
| 420 | * once the UART decides that there no new bytes arriving. |
| 421 | * - Once THRE is enabled, the interrupt will be fired once the FIFO is |
| 422 | * empty - the trigger level is ignored here. |
| 423 | * |
| 424 | * Once DMA is enabled: |
| 425 | * - UART will assert the TX DMA line once there is room for TX_TRIGGER |
| 426 | * bytes in the TX FIFO. On each assert the DMA engine will move |
| 427 | * TX_TRIGGER bytes into the FIFO. |
| 428 | * - UART will assert the RX DMA line once there are RX_TRIGGER bytes in |
| 429 | * the FIFO and move RX_TRIGGER bytes. |
| 430 | * This is because threshold and trigger values are the same. |
| 431 | */ |
| 432 | up->fcr = UART_FCR_ENABLE_FIFO; |
| 433 | up->fcr |= TRIGGER_FCR_MASK(TX_TRIGGER) << OMAP_UART_FCR_TX_TRIG; |
| 434 | up->fcr |= TRIGGER_FCR_MASK(RX_TRIGGER) << OMAP_UART_FCR_RX_TRIG; |
| 435 | |
| 436 | priv->scr = OMAP_UART_SCR_RX_TRIG_GRANU1_MASK | OMAP_UART_SCR_TX_EMPTY | |
| 437 | OMAP_UART_SCR_TX_TRIG_GRANU1_MASK; |
| 438 | |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 439 | if (up->dma) |
| 440 | priv->scr |= OMAP_UART_SCR_DMAMODE_1 | |
| 441 | OMAP_UART_SCR_DMAMODE_CTL; |
| 442 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 443 | priv->xon = termios->c_cc[VSTART]; |
| 444 | priv->xoff = termios->c_cc[VSTOP]; |
| 445 | |
| 446 | priv->efr = 0; |
Peter Hurley | 391f93f | 2015-01-25 14:44:51 -0500 | [diff] [blame] | 447 | up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF); |
| 448 | |
Andy Shevchenko | 5db4f7f | 2016-08-16 15:06:54 +0300 | [diff] [blame] | 449 | if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) { |
Peter Hurley | 9719acc | 2015-01-25 14:44:52 -0500 | [diff] [blame] | 450 | /* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */ |
Peter Hurley | 391f93f | 2015-01-25 14:44:51 -0500 | [diff] [blame] | 451 | up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS; |
Peter Hurley | 9719acc | 2015-01-25 14:44:52 -0500 | [diff] [blame] | 452 | priv->efr |= UART_EFR_CTS; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 453 | } else if (up->port.flags & UPF_SOFT_FLOW) { |
| 454 | /* |
Peter Hurley | 5bac4b3 | 2015-06-27 09:28:55 -0400 | [diff] [blame] | 455 | * OMAP rx s/w flow control is borked; the transmitter remains |
| 456 | * stuck off even if rx flow control is subsequently disabled |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 457 | */ |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 458 | |
| 459 | /* |
| 460 | * IXOFF Flag: |
| 461 | * Enable XON/XOFF flow control on output. |
| 462 | * Transmit XON1, XOFF1 |
| 463 | */ |
Peter Hurley | 391f93f | 2015-01-25 14:44:51 -0500 | [diff] [blame] | 464 | if (termios->c_iflag & IXOFF) { |
| 465 | up->port.status |= UPSTAT_AUTOXOFF; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 466 | priv->efr |= OMAP_UART_SW_TX; |
Peter Hurley | 391f93f | 2015-01-25 14:44:51 -0500 | [diff] [blame] | 467 | } |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 468 | } |
| 469 | omap8250_restore_regs(up); |
| 470 | |
| 471 | spin_unlock_irq(&up->port.lock); |
| 472 | pm_runtime_mark_last_busy(port->dev); |
| 473 | pm_runtime_put_autosuspend(port->dev); |
| 474 | |
| 475 | /* calculate wakeup latency constraint */ |
| 476 | priv->calc_latency = USEC_PER_SEC * 64 * 8 / baud; |
| 477 | priv->latency = priv->calc_latency; |
| 478 | |
| 479 | schedule_work(&priv->qos_work); |
| 480 | |
| 481 | /* Don't rewrite B0 */ |
| 482 | if (tty_termios_baud_rate(termios)) |
| 483 | tty_termios_encode_baud_rate(termios, baud, baud); |
| 484 | } |
| 485 | |
| 486 | /* same as 8250 except that we may have extra flow bits set in EFR */ |
| 487 | static void omap_8250_pm(struct uart_port *port, unsigned int state, |
| 488 | unsigned int oldstate) |
| 489 | { |
Peter Hurley | 3e29af2 | 2014-12-31 16:32:49 -0500 | [diff] [blame] | 490 | struct uart_8250_port *up = up_to_u8250p(port); |
| 491 | u8 efr; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 492 | |
| 493 | pm_runtime_get_sync(port->dev); |
| 494 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
Peter Hurley | 3e29af2 | 2014-12-31 16:32:49 -0500 | [diff] [blame] | 495 | efr = serial_in(up, UART_EFR); |
| 496 | serial_out(up, UART_EFR, efr | UART_EFR_ECB); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 497 | serial_out(up, UART_LCR, 0); |
| 498 | |
| 499 | serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0); |
| 500 | serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
Peter Hurley | 3e29af2 | 2014-12-31 16:32:49 -0500 | [diff] [blame] | 501 | serial_out(up, UART_EFR, efr); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 502 | serial_out(up, UART_LCR, 0); |
| 503 | |
| 504 | pm_runtime_mark_last_busy(port->dev); |
| 505 | pm_runtime_put_autosuspend(port->dev); |
| 506 | } |
| 507 | |
| 508 | static void omap_serial_fill_features_erratas(struct uart_8250_port *up, |
| 509 | struct omap8250_priv *priv) |
| 510 | { |
| 511 | u32 mvr, scheme; |
| 512 | u16 revision, major, minor; |
| 513 | |
| 514 | mvr = uart_read(up, UART_OMAP_MVER); |
| 515 | |
| 516 | /* Check revision register scheme */ |
| 517 | scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT; |
| 518 | |
| 519 | switch (scheme) { |
| 520 | case 0: /* Legacy Scheme: OMAP2/3 */ |
| 521 | /* MINOR_REV[0:4], MAJOR_REV[4:7] */ |
| 522 | major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >> |
| 523 | OMAP_UART_LEGACY_MVR_MAJ_SHIFT; |
| 524 | minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK); |
| 525 | break; |
| 526 | case 1: |
| 527 | /* New Scheme: OMAP4+ */ |
| 528 | /* MINOR_REV[0:5], MAJOR_REV[8:10] */ |
| 529 | major = (mvr & OMAP_UART_MVR_MAJ_MASK) >> |
| 530 | OMAP_UART_MVR_MAJ_SHIFT; |
| 531 | minor = (mvr & OMAP_UART_MVR_MIN_MASK); |
| 532 | break; |
| 533 | default: |
| 534 | dev_warn(up->port.dev, |
| 535 | "Unknown revision, defaulting to highest\n"); |
| 536 | /* highest possible revision */ |
| 537 | major = 0xff; |
| 538 | minor = 0xff; |
| 539 | } |
| 540 | /* normalize revision for the driver */ |
| 541 | revision = UART_BUILD_REVISION(major, minor); |
| 542 | |
| 543 | switch (revision) { |
| 544 | case OMAP_UART_REV_46: |
Sekhar Nori | 4fcdff9 | 2015-07-14 13:32:06 +0530 | [diff] [blame] | 545 | priv->habit |= UART_ERRATA_i202_MDR1_ACCESS; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 546 | break; |
| 547 | case OMAP_UART_REV_52: |
Sekhar Nori | 4fcdff9 | 2015-07-14 13:32:06 +0530 | [diff] [blame] | 548 | priv->habit |= UART_ERRATA_i202_MDR1_ACCESS | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 549 | OMAP_UART_WER_HAS_TX_WAKEUP; |
| 550 | break; |
| 551 | case OMAP_UART_REV_63: |
Sekhar Nori | 4fcdff9 | 2015-07-14 13:32:06 +0530 | [diff] [blame] | 552 | priv->habit |= UART_ERRATA_i202_MDR1_ACCESS | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 553 | OMAP_UART_WER_HAS_TX_WAKEUP; |
| 554 | break; |
| 555 | default: |
| 556 | break; |
| 557 | } |
| 558 | } |
| 559 | |
| 560 | static void omap8250_uart_qos_work(struct work_struct *work) |
| 561 | { |
| 562 | struct omap8250_priv *priv; |
| 563 | |
| 564 | priv = container_of(work, struct omap8250_priv, qos_work); |
| 565 | pm_qos_update_request(&priv->pm_qos_request, priv->latency); |
| 566 | } |
| 567 | |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 568 | #ifdef CONFIG_SERIAL_8250_DMA |
| 569 | static int omap_8250_dma_handle_irq(struct uart_port *port); |
| 570 | #endif |
| 571 | |
| 572 | static irqreturn_t omap8250_irq(int irq, void *dev_id) |
| 573 | { |
| 574 | struct uart_port *port = dev_id; |
| 575 | struct uart_8250_port *up = up_to_u8250p(port); |
| 576 | unsigned int iir; |
| 577 | int ret; |
| 578 | |
| 579 | #ifdef CONFIG_SERIAL_8250_DMA |
| 580 | if (up->dma) { |
| 581 | ret = omap_8250_dma_handle_irq(port); |
| 582 | return IRQ_RETVAL(ret); |
| 583 | } |
| 584 | #endif |
| 585 | |
| 586 | serial8250_rpm_get(up); |
| 587 | iir = serial_port_in(port, UART_IIR); |
| 588 | ret = serial8250_handle_irq(port, iir); |
| 589 | serial8250_rpm_put(up); |
| 590 | |
| 591 | return IRQ_RETVAL(ret); |
| 592 | } |
| 593 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 594 | static int omap_8250_startup(struct uart_port *port) |
| 595 | { |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 596 | struct uart_8250_port *up = up_to_u8250p(port); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 597 | struct omap8250_priv *priv = port->private_data; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 598 | int ret; |
| 599 | |
| 600 | if (priv->wakeirq) { |
Tony Lindgren | a3e362f | 2015-06-09 23:35:00 -0700 | [diff] [blame] | 601 | ret = dev_pm_set_dedicated_wake_irq(port->dev, priv->wakeirq); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 602 | if (ret) |
| 603 | return ret; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 604 | } |
| 605 | |
| 606 | pm_runtime_get_sync(port->dev); |
| 607 | |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 608 | up->mcr = 0; |
| 609 | serial_out(up, UART_FCR, UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); |
| 610 | |
| 611 | serial_out(up, UART_LCR, UART_LCR_WLEN8); |
| 612 | |
| 613 | up->lsr_saved_flags = 0; |
| 614 | up->msr_saved_flags = 0; |
| 615 | |
Vignesh R | 65db564 | 2017-04-22 18:37:19 +0530 | [diff] [blame] | 616 | /* Disable DMA for console UART */ |
| 617 | if (uart_console(port)) |
| 618 | up->dma = NULL; |
| 619 | |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 620 | if (up->dma) { |
| 621 | ret = serial8250_request_dma(up); |
| 622 | if (ret) { |
| 623 | dev_warn_ratelimited(port->dev, |
| 624 | "failed to request DMA\n"); |
| 625 | up->dma = NULL; |
| 626 | } |
| 627 | } |
| 628 | |
| 629 | ret = request_irq(port->irq, omap8250_irq, IRQF_SHARED, |
| 630 | dev_name(port->dev), port); |
| 631 | if (ret < 0) |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 632 | goto err; |
| 633 | |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 634 | up->ier = UART_IER_RLSI | UART_IER_RDI; |
| 635 | serial_out(up, UART_IER, up->ier); |
| 636 | |
Rafael J. Wysocki | 71504e5 | 2014-12-19 15:27:58 +0100 | [diff] [blame] | 637 | #ifdef CONFIG_PM |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 638 | up->capabilities |= UART_CAP_RPM; |
| 639 | #endif |
| 640 | |
| 641 | /* Enable module level wake up */ |
| 642 | priv->wer = OMAP_UART_WER_MOD_WKUP; |
| 643 | if (priv->habit & OMAP_UART_WER_HAS_TX_WAKEUP) |
| 644 | priv->wer |= OMAP_UART_TX_WAKEUP_EN; |
| 645 | serial_out(up, UART_OMAP_WER, priv->wer); |
| 646 | |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 647 | if (up->dma) |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 648 | up->dma->rx_dma(up); |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 649 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 650 | pm_runtime_mark_last_busy(port->dev); |
| 651 | pm_runtime_put_autosuspend(port->dev); |
| 652 | return 0; |
| 653 | err: |
| 654 | pm_runtime_mark_last_busy(port->dev); |
| 655 | pm_runtime_put_autosuspend(port->dev); |
Tony Lindgren | a3e362f | 2015-06-09 23:35:00 -0700 | [diff] [blame] | 656 | dev_pm_clear_wake_irq(port->dev); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 657 | return ret; |
| 658 | } |
| 659 | |
| 660 | static void omap_8250_shutdown(struct uart_port *port) |
| 661 | { |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 662 | struct uart_8250_port *up = up_to_u8250p(port); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 663 | struct omap8250_priv *priv = port->private_data; |
| 664 | |
| 665 | flush_work(&priv->qos_work); |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 666 | if (up->dma) |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 667 | omap_8250_rx_dma_flush(up); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 668 | |
| 669 | pm_runtime_get_sync(port->dev); |
| 670 | |
| 671 | serial_out(up, UART_OMAP_WER, 0); |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 672 | |
| 673 | up->ier = 0; |
| 674 | serial_out(up, UART_IER, 0); |
| 675 | |
| 676 | if (up->dma) |
| 677 | serial8250_release_dma(up); |
| 678 | |
| 679 | /* |
| 680 | * Disable break condition and FIFOs |
| 681 | */ |
| 682 | if (up->lcr & UART_LCR_SBC) |
| 683 | serial_out(up, UART_LCR, up->lcr & ~UART_LCR_SBC); |
| 684 | serial_out(up, UART_FCR, UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 685 | |
| 686 | pm_runtime_mark_last_busy(port->dev); |
| 687 | pm_runtime_put_autosuspend(port->dev); |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 688 | free_irq(port->irq, port); |
Tony Lindgren | a3e362f | 2015-06-09 23:35:00 -0700 | [diff] [blame] | 689 | dev_pm_clear_wake_irq(port->dev); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 690 | } |
| 691 | |
| 692 | static void omap_8250_throttle(struct uart_port *port) |
| 693 | { |
Andy Shevchenko | 013e358 | 2016-02-18 21:22:59 +0200 | [diff] [blame] | 694 | struct uart_8250_port *up = up_to_u8250p(port); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 695 | unsigned long flags; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 696 | |
| 697 | pm_runtime_get_sync(port->dev); |
| 698 | |
| 699 | spin_lock_irqsave(&port->lock, flags); |
| 700 | up->ier &= ~(UART_IER_RLSI | UART_IER_RDI); |
| 701 | serial_out(up, UART_IER, up->ier); |
| 702 | spin_unlock_irqrestore(&port->lock, flags); |
| 703 | |
| 704 | pm_runtime_mark_last_busy(port->dev); |
| 705 | pm_runtime_put_autosuspend(port->dev); |
| 706 | } |
| 707 | |
Matwey V. Kornilov | 344cee2 | 2016-02-01 21:09:22 +0300 | [diff] [blame] | 708 | static int omap_8250_rs485_config(struct uart_port *port, |
| 709 | struct serial_rs485 *rs485) |
| 710 | { |
| 711 | struct uart_8250_port *up = up_to_u8250p(port); |
| 712 | |
| 713 | /* Clamp the delays to [0, 100ms] */ |
| 714 | rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U); |
| 715 | rs485->delay_rts_after_send = min(rs485->delay_rts_after_send, 100U); |
| 716 | |
| 717 | port->rs485 = *rs485; |
| 718 | |
| 719 | /* |
| 720 | * Both serial8250_em485_init and serial8250_em485_destroy |
| 721 | * are idempotent |
| 722 | */ |
| 723 | if (rs485->flags & SER_RS485_ENABLED) { |
| 724 | int ret = serial8250_em485_init(up); |
| 725 | |
| 726 | if (ret) { |
| 727 | rs485->flags &= ~SER_RS485_ENABLED; |
| 728 | port->rs485.flags &= ~SER_RS485_ENABLED; |
| 729 | } |
| 730 | return ret; |
| 731 | } |
| 732 | |
| 733 | serial8250_em485_destroy(up); |
| 734 | |
| 735 | return 0; |
| 736 | } |
| 737 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 738 | static void omap_8250_unthrottle(struct uart_port *port) |
| 739 | { |
Andy Shevchenko | 013e358 | 2016-02-18 21:22:59 +0200 | [diff] [blame] | 740 | struct uart_8250_port *up = up_to_u8250p(port); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 741 | unsigned long flags; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 742 | |
| 743 | pm_runtime_get_sync(port->dev); |
| 744 | |
| 745 | spin_lock_irqsave(&port->lock, flags); |
| 746 | up->ier |= UART_IER_RLSI | UART_IER_RDI; |
| 747 | serial_out(up, UART_IER, up->ier); |
| 748 | spin_unlock_irqrestore(&port->lock, flags); |
| 749 | |
| 750 | pm_runtime_mark_last_busy(port->dev); |
| 751 | pm_runtime_put_autosuspend(port->dev); |
| 752 | } |
| 753 | |
Sebastian Andrzej Siewior | 31a1713 | 2014-09-29 20:06:43 +0200 | [diff] [blame] | 754 | #ifdef CONFIG_SERIAL_8250_DMA |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 755 | static int omap_8250_rx_dma(struct uart_8250_port *p); |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 756 | |
Peter Hurley | b74fdd2 | 2016-04-09 22:14:35 -0700 | [diff] [blame] | 757 | static void __dma_rx_do_complete(struct uart_8250_port *p) |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 758 | { |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 759 | struct omap8250_priv *priv = p->port.private_data; |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 760 | struct uart_8250_dma *dma = p->dma; |
| 761 | struct tty_port *tty_port = &p->port.state->port; |
| 762 | struct dma_tx_state state; |
| 763 | int count; |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 764 | unsigned long flags; |
Sebastian Andrzej Siewior | 658e2eb | 2015-08-14 18:01:03 +0200 | [diff] [blame] | 765 | int ret; |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 766 | |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 767 | spin_lock_irqsave(&priv->rx_dma_lock, flags); |
| 768 | |
| 769 | if (!dma->rx_running) |
| 770 | goto unlock; |
| 771 | |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 772 | dma->rx_running = 0; |
| 773 | dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state); |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 774 | |
| 775 | count = dma->rx_size - state.residue; |
| 776 | |
Sebastian Andrzej Siewior | 658e2eb | 2015-08-14 18:01:03 +0200 | [diff] [blame] | 777 | ret = tty_insert_flip_string(tty_port, dma->rx_buf, count); |
| 778 | |
| 779 | p->port.icount.rx += ret; |
| 780 | p->port.icount.buf_overrun += count - ret; |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 781 | unlock: |
| 782 | spin_unlock_irqrestore(&priv->rx_dma_lock, flags); |
| 783 | |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 784 | tty_flip_buffer_push(tty_port); |
| 785 | } |
| 786 | |
| 787 | static void __dma_rx_complete(void *param) |
| 788 | { |
Peter Hurley | b74fdd2 | 2016-04-09 22:14:35 -0700 | [diff] [blame] | 789 | __dma_rx_do_complete(param); |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 790 | omap_8250_rx_dma(param); |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 791 | } |
| 792 | |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 793 | static void omap_8250_rx_dma_flush(struct uart_8250_port *p) |
| 794 | { |
| 795 | struct omap8250_priv *priv = p->port.private_data; |
| 796 | struct uart_8250_dma *dma = p->dma; |
| 797 | unsigned long flags; |
Sebastian Andrzej Siewior | 830acf9 | 2015-08-14 17:52:07 +0200 | [diff] [blame] | 798 | int ret; |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 799 | |
| 800 | spin_lock_irqsave(&priv->rx_dma_lock, flags); |
| 801 | |
| 802 | if (!dma->rx_running) { |
| 803 | spin_unlock_irqrestore(&priv->rx_dma_lock, flags); |
| 804 | return; |
| 805 | } |
| 806 | |
Sebastian Andrzej Siewior | 830acf9 | 2015-08-14 17:52:07 +0200 | [diff] [blame] | 807 | ret = dmaengine_pause(dma->rxchan); |
| 808 | if (WARN_ON_ONCE(ret)) |
| 809 | priv->rx_dma_broken = true; |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 810 | |
| 811 | spin_unlock_irqrestore(&priv->rx_dma_lock, flags); |
| 812 | |
Peter Hurley | b74fdd2 | 2016-04-09 22:14:35 -0700 | [diff] [blame] | 813 | __dma_rx_do_complete(p); |
Peter Hurley | d1f9815 | 2016-04-09 22:14:37 -0700 | [diff] [blame] | 814 | dmaengine_terminate_all(dma->rxchan); |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 815 | } |
| 816 | |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 817 | static int omap_8250_rx_dma(struct uart_8250_port *p) |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 818 | { |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 819 | struct omap8250_priv *priv = p->port.private_data; |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 820 | struct uart_8250_dma *dma = p->dma; |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 821 | int err = 0; |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 822 | struct dma_async_tx_descriptor *desc; |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 823 | unsigned long flags; |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 824 | |
Sebastian Andrzej Siewior | 830acf9 | 2015-08-14 17:52:07 +0200 | [diff] [blame] | 825 | if (priv->rx_dma_broken) |
| 826 | return -EINVAL; |
| 827 | |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 828 | spin_lock_irqsave(&priv->rx_dma_lock, flags); |
| 829 | |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 830 | if (dma->rx_running) |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 831 | goto out; |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 832 | |
| 833 | desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr, |
| 834 | dma->rx_size, DMA_DEV_TO_MEM, |
| 835 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 836 | if (!desc) { |
| 837 | err = -EBUSY; |
| 838 | goto out; |
| 839 | } |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 840 | |
| 841 | dma->rx_running = 1; |
| 842 | desc->callback = __dma_rx_complete; |
| 843 | desc->callback_param = p; |
| 844 | |
| 845 | dma->rx_cookie = dmaengine_submit(desc); |
| 846 | |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 847 | dma_async_issue_pending(dma->rxchan); |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 848 | out: |
| 849 | spin_unlock_irqrestore(&priv->rx_dma_lock, flags); |
| 850 | return err; |
Sebastian Andrzej Siewior | 0e31c8d | 2014-09-29 20:06:44 +0200 | [diff] [blame] | 851 | } |
| 852 | |
Sebastian Andrzej Siewior | 31a1713 | 2014-09-29 20:06:43 +0200 | [diff] [blame] | 853 | static int omap_8250_tx_dma(struct uart_8250_port *p); |
| 854 | |
| 855 | static void omap_8250_dma_tx_complete(void *param) |
| 856 | { |
| 857 | struct uart_8250_port *p = param; |
| 858 | struct uart_8250_dma *dma = p->dma; |
| 859 | struct circ_buf *xmit = &p->port.state->xmit; |
| 860 | unsigned long flags; |
| 861 | bool en_thri = false; |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 862 | struct omap8250_priv *priv = p->port.private_data; |
Sebastian Andrzej Siewior | 31a1713 | 2014-09-29 20:06:43 +0200 | [diff] [blame] | 863 | |
| 864 | dma_sync_single_for_cpu(dma->txchan->device->dev, dma->tx_addr, |
| 865 | UART_XMIT_SIZE, DMA_TO_DEVICE); |
| 866 | |
| 867 | spin_lock_irqsave(&p->port.lock, flags); |
| 868 | |
| 869 | dma->tx_running = 0; |
| 870 | |
| 871 | xmit->tail += dma->tx_size; |
| 872 | xmit->tail &= UART_XMIT_SIZE - 1; |
| 873 | p->port.icount.tx += dma->tx_size; |
| 874 | |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 875 | if (priv->delayed_restore) { |
| 876 | priv->delayed_restore = 0; |
| 877 | omap8250_restore_regs(p); |
| 878 | } |
| 879 | |
Sebastian Andrzej Siewior | 31a1713 | 2014-09-29 20:06:43 +0200 | [diff] [blame] | 880 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) |
| 881 | uart_write_wakeup(&p->port); |
| 882 | |
| 883 | if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) { |
| 884 | int ret; |
| 885 | |
| 886 | ret = omap_8250_tx_dma(p); |
| 887 | if (ret) |
| 888 | en_thri = true; |
| 889 | |
| 890 | } else if (p->capabilities & UART_CAP_RPM) { |
| 891 | en_thri = true; |
| 892 | } |
| 893 | |
| 894 | if (en_thri) { |
| 895 | dma->tx_err = 1; |
| 896 | p->ier |= UART_IER_THRI; |
| 897 | serial_port_out(&p->port, UART_IER, p->ier); |
| 898 | } |
| 899 | |
| 900 | spin_unlock_irqrestore(&p->port.lock, flags); |
| 901 | } |
| 902 | |
| 903 | static int omap_8250_tx_dma(struct uart_8250_port *p) |
| 904 | { |
| 905 | struct uart_8250_dma *dma = p->dma; |
| 906 | struct omap8250_priv *priv = p->port.private_data; |
| 907 | struct circ_buf *xmit = &p->port.state->xmit; |
| 908 | struct dma_async_tx_descriptor *desc; |
| 909 | unsigned int skip_byte = 0; |
| 910 | int ret; |
| 911 | |
| 912 | if (dma->tx_running) |
| 913 | return 0; |
| 914 | if (uart_tx_stopped(&p->port) || uart_circ_empty(xmit)) { |
| 915 | |
| 916 | /* |
| 917 | * Even if no data, we need to return an error for the two cases |
| 918 | * below so serial8250_tx_chars() is invoked and properly clears |
| 919 | * THRI and/or runtime suspend. |
| 920 | */ |
| 921 | if (dma->tx_err || p->capabilities & UART_CAP_RPM) { |
| 922 | ret = -EBUSY; |
| 923 | goto err; |
| 924 | } |
| 925 | if (p->ier & UART_IER_THRI) { |
| 926 | p->ier &= ~UART_IER_THRI; |
| 927 | serial_out(p, UART_IER, p->ier); |
| 928 | } |
| 929 | return 0; |
| 930 | } |
| 931 | |
| 932 | dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); |
| 933 | if (priv->habit & OMAP_DMA_TX_KICK) { |
| 934 | u8 tx_lvl; |
| 935 | |
| 936 | /* |
| 937 | * We need to put the first byte into the FIFO in order to start |
| 938 | * the DMA transfer. For transfers smaller than four bytes we |
| 939 | * don't bother doing DMA at all. It seem not matter if there |
| 940 | * are still bytes in the FIFO from the last transfer (in case |
| 941 | * we got here directly from omap_8250_dma_tx_complete()). Bytes |
| 942 | * leaving the FIFO seem not to trigger the DMA transfer. It is |
| 943 | * really the byte that we put into the FIFO. |
| 944 | * If the FIFO is already full then we most likely got here from |
| 945 | * omap_8250_dma_tx_complete(). And this means the DMA engine |
| 946 | * just completed its work. We don't have to wait the complete |
| 947 | * 86us at 115200,8n1 but around 60us (not to mention lower |
| 948 | * baudrates). So in that case we take the interrupt and try |
| 949 | * again with an empty FIFO. |
| 950 | */ |
| 951 | tx_lvl = serial_in(p, UART_OMAP_TX_LVL); |
| 952 | if (tx_lvl == p->tx_loadsz) { |
| 953 | ret = -EBUSY; |
| 954 | goto err; |
| 955 | } |
| 956 | if (dma->tx_size < 4) { |
| 957 | ret = -EINVAL; |
| 958 | goto err; |
| 959 | } |
| 960 | skip_byte = 1; |
| 961 | } |
| 962 | |
| 963 | desc = dmaengine_prep_slave_single(dma->txchan, |
| 964 | dma->tx_addr + xmit->tail + skip_byte, |
| 965 | dma->tx_size - skip_byte, DMA_MEM_TO_DEV, |
| 966 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
| 967 | if (!desc) { |
| 968 | ret = -EBUSY; |
| 969 | goto err; |
| 970 | } |
| 971 | |
| 972 | dma->tx_running = 1; |
| 973 | |
| 974 | desc->callback = omap_8250_dma_tx_complete; |
| 975 | desc->callback_param = p; |
| 976 | |
| 977 | dma->tx_cookie = dmaengine_submit(desc); |
| 978 | |
| 979 | dma_sync_single_for_device(dma->txchan->device->dev, dma->tx_addr, |
| 980 | UART_XMIT_SIZE, DMA_TO_DEVICE); |
| 981 | |
| 982 | dma_async_issue_pending(dma->txchan); |
| 983 | if (dma->tx_err) |
| 984 | dma->tx_err = 0; |
| 985 | |
| 986 | if (p->ier & UART_IER_THRI) { |
| 987 | p->ier &= ~UART_IER_THRI; |
| 988 | serial_out(p, UART_IER, p->ier); |
| 989 | } |
| 990 | if (skip_byte) |
| 991 | serial_out(p, UART_TX, xmit->buf[xmit->tail]); |
| 992 | return 0; |
| 993 | err: |
| 994 | dma->tx_err = 1; |
| 995 | return ret; |
| 996 | } |
| 997 | |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 998 | static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir) |
| 999 | { |
| 1000 | switch (iir & 0x3f) { |
| 1001 | case UART_IIR_RLSI: |
| 1002 | case UART_IIR_RX_TIMEOUT: |
| 1003 | case UART_IIR_RDI: |
| 1004 | omap_8250_rx_dma_flush(up); |
| 1005 | return true; |
| 1006 | } |
| 1007 | return omap_8250_rx_dma(up); |
| 1008 | } |
| 1009 | |
Sebastian Andrzej Siewior | 7728524 | 2014-09-29 20:06:48 +0200 | [diff] [blame] | 1010 | /* |
| 1011 | * This is mostly serial8250_handle_irq(). We have a slightly different DMA |
| 1012 | * hoook for RX/TX and need different logic for them in the ISR. Therefore we |
| 1013 | * use the default routine in the non-DMA case and this one for with DMA. |
| 1014 | */ |
| 1015 | static int omap_8250_dma_handle_irq(struct uart_port *port) |
| 1016 | { |
| 1017 | struct uart_8250_port *up = up_to_u8250p(port); |
| 1018 | unsigned char status; |
| 1019 | unsigned long flags; |
| 1020 | u8 iir; |
Sebastian Andrzej Siewior | 7728524 | 2014-09-29 20:06:48 +0200 | [diff] [blame] | 1021 | |
| 1022 | serial8250_rpm_get(up); |
| 1023 | |
| 1024 | iir = serial_port_in(port, UART_IIR); |
| 1025 | if (iir & UART_IIR_NO_INT) { |
| 1026 | serial8250_rpm_put(up); |
| 1027 | return 0; |
| 1028 | } |
| 1029 | |
| 1030 | spin_lock_irqsave(&port->lock, flags); |
| 1031 | |
| 1032 | status = serial_port_in(port, UART_LSR); |
| 1033 | |
| 1034 | if (status & (UART_LSR_DR | UART_LSR_BI)) { |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 1035 | if (handle_rx_dma(up, iir)) { |
Sebastian Andrzej Siewior | 7728524 | 2014-09-29 20:06:48 +0200 | [diff] [blame] | 1036 | status = serial8250_rx_chars(up, status); |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 1037 | omap_8250_rx_dma(up); |
Sebastian Andrzej Siewior | 7728524 | 2014-09-29 20:06:48 +0200 | [diff] [blame] | 1038 | } |
| 1039 | } |
| 1040 | serial8250_modem_status(up); |
| 1041 | if (status & UART_LSR_THRE && up->dma->tx_err) { |
| 1042 | if (uart_tx_stopped(&up->port) || |
| 1043 | uart_circ_empty(&up->port.state->xmit)) { |
| 1044 | up->dma->tx_err = 0; |
| 1045 | serial8250_tx_chars(up); |
| 1046 | } else { |
| 1047 | /* |
| 1048 | * try again due to an earlier failer which |
| 1049 | * might have been resolved by now. |
| 1050 | */ |
Peter Hurley | a86f50e | 2016-04-09 20:49:41 -0700 | [diff] [blame] | 1051 | if (omap_8250_tx_dma(up)) |
Sebastian Andrzej Siewior | 7728524 | 2014-09-29 20:06:48 +0200 | [diff] [blame] | 1052 | serial8250_tx_chars(up); |
| 1053 | } |
| 1054 | } |
| 1055 | |
| 1056 | spin_unlock_irqrestore(&port->lock, flags); |
| 1057 | serial8250_rpm_put(up); |
| 1058 | return 1; |
| 1059 | } |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 1060 | |
| 1061 | static bool the_no_dma_filter_fn(struct dma_chan *chan, void *param) |
| 1062 | { |
| 1063 | return false; |
| 1064 | } |
| 1065 | |
| 1066 | #else |
| 1067 | |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 1068 | static inline int omap_8250_rx_dma(struct uart_8250_port *p) |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 1069 | { |
| 1070 | return -EINVAL; |
| 1071 | } |
Sebastian Andrzej Siewior | 31a1713 | 2014-09-29 20:06:43 +0200 | [diff] [blame] | 1072 | #endif |
| 1073 | |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 1074 | static int omap8250_no_handle_irq(struct uart_port *port) |
| 1075 | { |
| 1076 | /* IRQ has not been requested but handling irq? */ |
| 1077 | WARN_ONCE(1, "Unexpected irq handling before port startup\n"); |
| 1078 | return 0; |
| 1079 | } |
| 1080 | |
Sekhar Nori | cdb929e | 2015-07-14 13:32:07 +0530 | [diff] [blame] | 1081 | static const u8 am3352_habit = OMAP_DMA_TX_KICK | UART_ERRATA_CLOCK_DISABLE; |
Vignesh R | 80b0d7e | 2017-04-04 19:32:22 +0000 | [diff] [blame] | 1082 | static const u8 dra742_habit = UART_ERRATA_CLOCK_DISABLE; |
Sekhar Nori | 4fcdff9 | 2015-07-14 13:32:06 +0530 | [diff] [blame] | 1083 | |
| 1084 | static const struct of_device_id omap8250_dt_ids[] = { |
| 1085 | { .compatible = "ti,omap2-uart" }, |
| 1086 | { .compatible = "ti,omap3-uart" }, |
| 1087 | { .compatible = "ti,omap4-uart" }, |
| 1088 | { .compatible = "ti,am3352-uart", .data = &am3352_habit, }, |
Vignesh R | 80b0d7e | 2017-04-04 19:32:22 +0000 | [diff] [blame] | 1089 | { .compatible = "ti,am4372-uart", .data = &am3352_habit, }, |
| 1090 | { .compatible = "ti,dra742-uart", .data = &dra742_habit, }, |
Sekhar Nori | 4fcdff9 | 2015-07-14 13:32:06 +0530 | [diff] [blame] | 1091 | {}, |
| 1092 | }; |
| 1093 | MODULE_DEVICE_TABLE(of, omap8250_dt_ids); |
| 1094 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1095 | static int omap8250_probe(struct platform_device *pdev) |
| 1096 | { |
| 1097 | struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 1098 | struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); |
| 1099 | struct omap8250_priv *priv; |
| 1100 | struct uart_8250_port up; |
| 1101 | int ret; |
| 1102 | void __iomem *membase; |
| 1103 | |
| 1104 | if (!regs || !irq) { |
| 1105 | dev_err(&pdev->dev, "missing registers or irq\n"); |
| 1106 | return -EINVAL; |
| 1107 | } |
| 1108 | |
| 1109 | priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); |
| 1110 | if (!priv) |
| 1111 | return -ENOMEM; |
| 1112 | |
| 1113 | membase = devm_ioremap_nocache(&pdev->dev, regs->start, |
| 1114 | resource_size(regs)); |
| 1115 | if (!membase) |
| 1116 | return -ENODEV; |
| 1117 | |
| 1118 | memset(&up, 0, sizeof(up)); |
| 1119 | up.port.dev = &pdev->dev; |
| 1120 | up.port.mapbase = regs->start; |
| 1121 | up.port.membase = membase; |
| 1122 | up.port.irq = irq->start; |
| 1123 | /* |
| 1124 | * It claims to be 16C750 compatible however it is a little different. |
| 1125 | * It has EFR and has no FCR7_64byte bit. The AFE (which it claims to |
| 1126 | * have) is enabled via EFR instead of MCR. The type is set here 8250 |
| 1127 | * just to get things going. UNKNOWN does not work for a few reasons and |
| 1128 | * we don't need our own type since we don't use 8250's set_termios() |
| 1129 | * or pm callback. |
| 1130 | */ |
| 1131 | up.port.type = PORT_8250; |
| 1132 | up.port.iotype = UPIO_MEM; |
| 1133 | up.port.flags = UPF_FIXED_PORT | UPF_FIXED_TYPE | UPF_SOFT_FLOW | |
| 1134 | UPF_HARD_FLOW; |
| 1135 | up.port.private_data = priv; |
| 1136 | |
| 1137 | up.port.regshift = 2; |
| 1138 | up.port.fifosize = 64; |
| 1139 | up.tx_loadsz = 64; |
| 1140 | up.capabilities = UART_CAP_FIFO; |
Rafael J. Wysocki | 71504e5 | 2014-12-19 15:27:58 +0100 | [diff] [blame] | 1141 | #ifdef CONFIG_PM |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1142 | /* |
Rafael J. Wysocki | 71504e5 | 2014-12-19 15:27:58 +0100 | [diff] [blame] | 1143 | * Runtime PM is mostly transparent. However to do it right we need to a |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1144 | * TX empty interrupt before we can put the device to auto idle. So if |
Rafael J. Wysocki | 71504e5 | 2014-12-19 15:27:58 +0100 | [diff] [blame] | 1145 | * PM is not enabled we don't add that flag and can spare that one extra |
| 1146 | * interrupt in the TX path. |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1147 | */ |
| 1148 | up.capabilities |= UART_CAP_RPM; |
| 1149 | #endif |
| 1150 | up.port.set_termios = omap_8250_set_termios; |
Peter Hurley | 4bf4ea9 | 2014-12-30 20:28:15 -0500 | [diff] [blame] | 1151 | up.port.set_mctrl = omap8250_set_mctrl; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1152 | up.port.pm = omap_8250_pm; |
| 1153 | up.port.startup = omap_8250_startup; |
| 1154 | up.port.shutdown = omap_8250_shutdown; |
| 1155 | up.port.throttle = omap_8250_throttle; |
| 1156 | up.port.unthrottle = omap_8250_unthrottle; |
Matwey V. Kornilov | 344cee2 | 2016-02-01 21:09:22 +0300 | [diff] [blame] | 1157 | up.port.rs485_config = omap_8250_rs485_config; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1158 | |
| 1159 | if (pdev->dev.of_node) { |
Sekhar Nori | 4fcdff9 | 2015-07-14 13:32:06 +0530 | [diff] [blame] | 1160 | const struct of_device_id *id; |
| 1161 | |
Sebastian Andrzej Siewior | 54178fe | 2014-11-12 10:28:33 +0100 | [diff] [blame] | 1162 | ret = of_alias_get_id(pdev->dev.of_node, "serial"); |
| 1163 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1164 | of_property_read_u32(pdev->dev.of_node, "clock-frequency", |
| 1165 | &up.port.uartclk); |
| 1166 | priv->wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1); |
Sekhar Nori | 4fcdff9 | 2015-07-14 13:32:06 +0530 | [diff] [blame] | 1167 | |
| 1168 | id = of_match_device(of_match_ptr(omap8250_dt_ids), &pdev->dev); |
| 1169 | if (id && id->data) |
| 1170 | priv->habit |= *(u8 *)id->data; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1171 | } else { |
Sebastian Andrzej Siewior | 54178fe | 2014-11-12 10:28:33 +0100 | [diff] [blame] | 1172 | ret = pdev->id; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1173 | } |
Sebastian Andrzej Siewior | 54178fe | 2014-11-12 10:28:33 +0100 | [diff] [blame] | 1174 | if (ret < 0) { |
| 1175 | dev_err(&pdev->dev, "failed to get alias/pdev id\n"); |
| 1176 | return ret; |
| 1177 | } |
| 1178 | up.port.line = ret; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1179 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1180 | if (!up.port.uartclk) { |
| 1181 | up.port.uartclk = DEFAULT_CLK_SPEED; |
| 1182 | dev_warn(&pdev->dev, |
| 1183 | "No clock speed specified: using default: %d\n", |
| 1184 | DEFAULT_CLK_SPEED); |
| 1185 | } |
| 1186 | |
| 1187 | priv->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; |
| 1188 | priv->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; |
| 1189 | pm_qos_add_request(&priv->pm_qos_request, PM_QOS_CPU_DMA_LATENCY, |
| 1190 | priv->latency); |
| 1191 | INIT_WORK(&priv->qos_work, omap8250_uart_qos_work); |
| 1192 | |
John Ogness | eda0cd3 | 2015-04-27 13:52:33 +0200 | [diff] [blame] | 1193 | spin_lock_init(&priv->rx_dma_lock); |
| 1194 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1195 | device_init_wakeup(&pdev->dev, true); |
| 1196 | pm_runtime_use_autosuspend(&pdev->dev); |
| 1197 | pm_runtime_set_autosuspend_delay(&pdev->dev, -1); |
| 1198 | |
| 1199 | pm_runtime_irq_safe(&pdev->dev); |
| 1200 | pm_runtime_enable(&pdev->dev); |
| 1201 | |
| 1202 | pm_runtime_get_sync(&pdev->dev); |
| 1203 | |
| 1204 | omap_serial_fill_features_erratas(&up, priv); |
Sebastian Andrzej Siewior | 9e91597 | 2015-05-20 22:07:35 +0200 | [diff] [blame] | 1205 | up.port.handle_irq = omap8250_no_handle_irq; |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 1206 | #ifdef CONFIG_SERIAL_8250_DMA |
| 1207 | if (pdev->dev.of_node) { |
| 1208 | /* |
| 1209 | * Oh DMA support. If there are no DMA properties in the DT then |
| 1210 | * we will fall back to a generic DMA channel which does not |
| 1211 | * really work here. To ensure that we do not get a generic DMA |
| 1212 | * channel assigned, we have the the_no_dma_filter_fn() here. |
| 1213 | * To avoid "failed to request DMA" messages we check for DMA |
| 1214 | * properties in DT. |
| 1215 | */ |
| 1216 | ret = of_property_count_strings(pdev->dev.of_node, "dma-names"); |
| 1217 | if (ret == 2) { |
| 1218 | up.dma = &priv->omap8250_dma; |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 1219 | priv->omap8250_dma.fn = the_no_dma_filter_fn; |
| 1220 | priv->omap8250_dma.tx_dma = omap_8250_tx_dma; |
| 1221 | priv->omap8250_dma.rx_dma = omap_8250_rx_dma; |
| 1222 | priv->omap8250_dma.rx_size = RX_TRIGGER; |
| 1223 | priv->omap8250_dma.rxconf.src_maxburst = RX_TRIGGER; |
| 1224 | priv->omap8250_dma.txconf.dst_maxburst = TX_TRIGGER; |
Sebastian Andrzej Siewior | 830acf9 | 2015-08-14 17:52:07 +0200 | [diff] [blame] | 1225 | /* |
| 1226 | * pause is currently not supported atleast on omap-sdma |
| 1227 | * and edma on most earlier kernels. |
| 1228 | */ |
| 1229 | priv->rx_dma_broken = true; |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 1230 | } |
| 1231 | } |
| 1232 | #endif |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1233 | ret = serial8250_register_8250_port(&up); |
| 1234 | if (ret < 0) { |
| 1235 | dev_err(&pdev->dev, "unable to register 8250 port\n"); |
| 1236 | goto err; |
| 1237 | } |
| 1238 | priv->line = ret; |
| 1239 | platform_set_drvdata(pdev, priv); |
| 1240 | pm_runtime_mark_last_busy(&pdev->dev); |
| 1241 | pm_runtime_put_autosuspend(&pdev->dev); |
| 1242 | return 0; |
| 1243 | err: |
Tony Lindgren | 71fd9a9 | 2017-01-20 12:22:31 -0800 | [diff] [blame] | 1244 | pm_runtime_dont_use_autosuspend(&pdev->dev); |
| 1245 | pm_runtime_put_sync(&pdev->dev); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1246 | pm_runtime_disable(&pdev->dev); |
| 1247 | return ret; |
| 1248 | } |
| 1249 | |
| 1250 | static int omap8250_remove(struct platform_device *pdev) |
| 1251 | { |
| 1252 | struct omap8250_priv *priv = platform_get_drvdata(pdev); |
| 1253 | |
Tony Lindgren | 71fd9a9 | 2017-01-20 12:22:31 -0800 | [diff] [blame] | 1254 | pm_runtime_dont_use_autosuspend(&pdev->dev); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1255 | pm_runtime_put_sync(&pdev->dev); |
| 1256 | pm_runtime_disable(&pdev->dev); |
| 1257 | serial8250_unregister_port(priv->line); |
| 1258 | pm_qos_remove_request(&priv->pm_qos_request); |
| 1259 | device_init_wakeup(&pdev->dev, false); |
| 1260 | return 0; |
| 1261 | } |
| 1262 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1263 | #ifdef CONFIG_PM_SLEEP |
| 1264 | static int omap8250_prepare(struct device *dev) |
| 1265 | { |
| 1266 | struct omap8250_priv *priv = dev_get_drvdata(dev); |
| 1267 | |
| 1268 | if (!priv) |
| 1269 | return 0; |
| 1270 | priv->is_suspending = true; |
| 1271 | return 0; |
| 1272 | } |
| 1273 | |
| 1274 | static void omap8250_complete(struct device *dev) |
| 1275 | { |
| 1276 | struct omap8250_priv *priv = dev_get_drvdata(dev); |
| 1277 | |
| 1278 | if (!priv) |
| 1279 | return; |
| 1280 | priv->is_suspending = false; |
| 1281 | } |
| 1282 | |
| 1283 | static int omap8250_suspend(struct device *dev) |
| 1284 | { |
| 1285 | struct omap8250_priv *priv = dev_get_drvdata(dev); |
| 1286 | |
| 1287 | serial8250_suspend_port(priv->line); |
| 1288 | flush_work(&priv->qos_work); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1289 | return 0; |
| 1290 | } |
| 1291 | |
| 1292 | static int omap8250_resume(struct device *dev) |
| 1293 | { |
| 1294 | struct omap8250_priv *priv = dev_get_drvdata(dev); |
| 1295 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1296 | serial8250_resume_port(priv->line); |
| 1297 | return 0; |
| 1298 | } |
| 1299 | #else |
| 1300 | #define omap8250_prepare NULL |
| 1301 | #define omap8250_complete NULL |
| 1302 | #endif |
| 1303 | |
Rafael J. Wysocki | 71504e5 | 2014-12-19 15:27:58 +0100 | [diff] [blame] | 1304 | #ifdef CONFIG_PM |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1305 | static int omap8250_lost_context(struct uart_8250_port *up) |
| 1306 | { |
| 1307 | u32 val; |
| 1308 | |
Sekhar Nori | cdb929e | 2015-07-14 13:32:07 +0530 | [diff] [blame] | 1309 | val = serial_in(up, UART_OMAP_SCR); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1310 | /* |
Sekhar Nori | cdb929e | 2015-07-14 13:32:07 +0530 | [diff] [blame] | 1311 | * If we lose context, then SCR is set to its reset value of zero. |
| 1312 | * After set_termios() we set bit 3 of SCR (TX_EMPTY_CTL_IT) to 1, |
| 1313 | * among other bits, to never set the register back to zero again. |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1314 | */ |
Sekhar Nori | cdb929e | 2015-07-14 13:32:07 +0530 | [diff] [blame] | 1315 | if (!val) |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1316 | return 1; |
| 1317 | return 0; |
| 1318 | } |
| 1319 | |
Sekhar Nori | cdb929e | 2015-07-14 13:32:07 +0530 | [diff] [blame] | 1320 | /* TODO: in future, this should happen via API in drivers/reset/ */ |
| 1321 | static int omap8250_soft_reset(struct device *dev) |
| 1322 | { |
| 1323 | struct omap8250_priv *priv = dev_get_drvdata(dev); |
| 1324 | struct uart_8250_port *up = serial8250_get_port(priv->line); |
| 1325 | int timeout = 100; |
| 1326 | int sysc; |
| 1327 | int syss; |
| 1328 | |
| 1329 | sysc = serial_in(up, UART_OMAP_SYSC); |
| 1330 | |
| 1331 | /* softreset the UART */ |
| 1332 | sysc |= OMAP_UART_SYSC_SOFTRESET; |
| 1333 | serial_out(up, UART_OMAP_SYSC, sysc); |
| 1334 | |
| 1335 | /* By experiments, 1us enough for reset complete on AM335x */ |
| 1336 | do { |
| 1337 | udelay(1); |
| 1338 | syss = serial_in(up, UART_OMAP_SYSS); |
| 1339 | } while (--timeout && !(syss & OMAP_UART_SYSS_RESETDONE)); |
| 1340 | |
| 1341 | if (!timeout) { |
| 1342 | dev_err(dev, "timed out waiting for reset done\n"); |
| 1343 | return -ETIMEDOUT; |
| 1344 | } |
| 1345 | |
| 1346 | return 0; |
| 1347 | } |
| 1348 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1349 | static int omap8250_runtime_suspend(struct device *dev) |
| 1350 | { |
| 1351 | struct omap8250_priv *priv = dev_get_drvdata(dev); |
| 1352 | struct uart_8250_port *up; |
| 1353 | |
Tony Lindgren | 71fd9a9 | 2017-01-20 12:22:31 -0800 | [diff] [blame] | 1354 | /* In case runtime-pm tries this before we are setup */ |
| 1355 | if (!priv) |
| 1356 | return 0; |
| 1357 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1358 | up = serial8250_get_port(priv->line); |
| 1359 | /* |
| 1360 | * When using 'no_console_suspend', the console UART must not be |
| 1361 | * suspended. Since driver suspend is managed by runtime suspend, |
| 1362 | * preventing runtime suspend (by returning error) will keep device |
| 1363 | * active during suspend. |
| 1364 | */ |
| 1365 | if (priv->is_suspending && !console_suspend_enabled) { |
| 1366 | if (uart_console(&up->port)) |
| 1367 | return -EBUSY; |
| 1368 | } |
| 1369 | |
Sekhar Nori | cdb929e | 2015-07-14 13:32:07 +0530 | [diff] [blame] | 1370 | if (priv->habit & UART_ERRATA_CLOCK_DISABLE) { |
| 1371 | int ret; |
| 1372 | |
| 1373 | ret = omap8250_soft_reset(dev); |
| 1374 | if (ret) |
| 1375 | return ret; |
| 1376 | |
| 1377 | /* Restore to UART mode after reset (for wakeup) */ |
| 1378 | omap8250_update_mdr1(up, priv); |
| 1379 | } |
| 1380 | |
Sekhar Nori | 727fd8a | 2015-07-14 13:32:03 +0530 | [diff] [blame] | 1381 | if (up->dma && up->dma->rxchan) |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 1382 | omap_8250_rx_dma_flush(up); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1383 | |
| 1384 | priv->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; |
| 1385 | schedule_work(&priv->qos_work); |
| 1386 | |
| 1387 | return 0; |
| 1388 | } |
| 1389 | |
| 1390 | static int omap8250_runtime_resume(struct device *dev) |
| 1391 | { |
| 1392 | struct omap8250_priv *priv = dev_get_drvdata(dev); |
| 1393 | struct uart_8250_port *up; |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1394 | |
| 1395 | /* In case runtime-pm tries this before we are setup */ |
| 1396 | if (!priv) |
| 1397 | return 0; |
| 1398 | |
| 1399 | up = serial8250_get_port(priv->line); |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1400 | |
Peter Hurley | f56f0a5 | 2016-04-09 20:49:43 -0700 | [diff] [blame] | 1401 | if (omap8250_lost_context(up)) |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1402 | omap8250_restore_regs(up); |
| 1403 | |
Sekhar Nori | 727fd8a | 2015-07-14 13:32:03 +0530 | [diff] [blame] | 1404 | if (up->dma && up->dma->rxchan) |
Peter Hurley | 33d9b8b2 | 2016-04-09 22:14:36 -0700 | [diff] [blame] | 1405 | omap_8250_rx_dma(up); |
Sebastian Andrzej Siewior | 0a0661d | 2014-09-29 20:06:49 +0200 | [diff] [blame] | 1406 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1407 | priv->latency = priv->calc_latency; |
| 1408 | schedule_work(&priv->qos_work); |
| 1409 | return 0; |
| 1410 | } |
| 1411 | #endif |
| 1412 | |
Sebastian Andrzej Siewior | 00648d0 | 2014-12-18 18:47:12 +0100 | [diff] [blame] | 1413 | #ifdef CONFIG_SERIAL_8250_OMAP_TTYO_FIXUP |
| 1414 | static int __init omap8250_console_fixup(void) |
| 1415 | { |
| 1416 | char *omap_str; |
| 1417 | char *options; |
| 1418 | u8 idx; |
| 1419 | |
| 1420 | if (strstr(boot_command_line, "console=ttyS")) |
| 1421 | /* user set a ttyS based name for the console */ |
| 1422 | return 0; |
| 1423 | |
| 1424 | omap_str = strstr(boot_command_line, "console=ttyO"); |
| 1425 | if (!omap_str) |
| 1426 | /* user did not set ttyO based console, so we don't care */ |
| 1427 | return 0; |
| 1428 | |
| 1429 | omap_str += 12; |
| 1430 | if ('0' <= *omap_str && *omap_str <= '9') |
| 1431 | idx = *omap_str - '0'; |
| 1432 | else |
| 1433 | return 0; |
| 1434 | |
| 1435 | omap_str++; |
| 1436 | if (omap_str[0] == ',') { |
| 1437 | omap_str++; |
| 1438 | options = omap_str; |
| 1439 | } else { |
| 1440 | options = NULL; |
| 1441 | } |
| 1442 | |
| 1443 | add_preferred_console("ttyS", idx, options); |
| 1444 | pr_err("WARNING: Your 'console=ttyO%d' has been replaced by 'ttyS%d'\n", |
| 1445 | idx, idx); |
| 1446 | pr_err("This ensures that you still see kernel messages. Please\n"); |
| 1447 | pr_err("update your kernel commandline.\n"); |
| 1448 | return 0; |
| 1449 | } |
| 1450 | console_initcall(omap8250_console_fixup); |
| 1451 | #endif |
| 1452 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1453 | static const struct dev_pm_ops omap8250_dev_pm_ops = { |
| 1454 | SET_SYSTEM_SLEEP_PM_OPS(omap8250_suspend, omap8250_resume) |
| 1455 | SET_RUNTIME_PM_OPS(omap8250_runtime_suspend, |
| 1456 | omap8250_runtime_resume, NULL) |
| 1457 | .prepare = omap8250_prepare, |
| 1458 | .complete = omap8250_complete, |
| 1459 | }; |
| 1460 | |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1461 | static struct platform_driver omap8250_platform_driver = { |
| 1462 | .driver = { |
| 1463 | .name = "omap8250", |
| 1464 | .pm = &omap8250_dev_pm_ops, |
| 1465 | .of_match_table = omap8250_dt_ids, |
Sebastian Andrzej Siewior | 61929cf | 2014-09-29 20:06:39 +0200 | [diff] [blame] | 1466 | }, |
| 1467 | .probe = omap8250_probe, |
| 1468 | .remove = omap8250_remove, |
| 1469 | }; |
| 1470 | module_platform_driver(omap8250_platform_driver); |
| 1471 | |
| 1472 | MODULE_AUTHOR("Sebastian Andrzej Siewior"); |
| 1473 | MODULE_DESCRIPTION("OMAP 8250 Driver"); |
| 1474 | MODULE_LICENSE("GPL v2"); |