| 1 | /* |
| 2 | * arch/arm/mach-omap2/serial.c |
| 3 | * |
| 4 | * OMAP2 serial support. |
| 5 | * |
| 6 | * Copyright (C) 2005-2008 Nokia Corporation |
| 7 | * Author: Paul Mundt <paul.mundt@nokia.com> |
| 8 | * |
| 9 | * Major rework for PM support by Kevin Hilman |
| 10 | * |
| 11 | * Based off of arch/arm/mach-omap/omap1/serial.c |
| 12 | * |
| 13 | * Copyright (C) 2009 Texas Instruments |
| 14 | * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com |
| 15 | * |
| 16 | * This file is subject to the terms and conditions of the GNU General Public |
| 17 | * License. See the file "COPYING" in the main directory of this archive |
| 18 | * for more details. |
| 19 | */ |
| 20 | #include <linux/kernel.h> |
| 21 | #include <linux/init.h> |
| 22 | #include <linux/clk.h> |
| 23 | #include <linux/io.h> |
| 24 | #include <linux/delay.h> |
| 25 | #include <linux/platform_device.h> |
| 26 | #include <linux/slab.h> |
| 27 | #include <linux/pm_runtime.h> |
| 28 | #include <linux/console.h> |
| 29 | #include <linux/omap-dma.h> |
| 30 | #include <linux/platform_data/serial-omap.h> |
| 31 | |
| 32 | #include "common.h" |
| 33 | #include "omap_hwmod.h" |
| 34 | #include "omap_device.h" |
| 35 | #include "omap-pm.h" |
| 36 | #include "soc.h" |
| 37 | #include "prm2xxx_3xxx.h" |
| 38 | #include "pm.h" |
| 39 | #include "cm2xxx_3xxx.h" |
| 40 | #include "prm-regbits-34xx.h" |
| 41 | #include "control.h" |
| 42 | #include "mux.h" |
| 43 | #include "serial.h" |
| 44 | |
| 45 | /* |
| 46 | * NOTE: By default the serial auto_suspend timeout is disabled as it causes |
| 47 | * lost characters over the serial ports. This means that the UART clocks will |
| 48 | * stay on until power/autosuspend_delay is set for the uart from sysfs. |
| 49 | * This also causes that any deeper omap sleep states are blocked. |
| 50 | */ |
| 51 | #define DEFAULT_AUTOSUSPEND_DELAY -1 |
| 52 | |
| 53 | #define MAX_UART_HWMOD_NAME_LEN 16 |
| 54 | |
| 55 | struct omap_uart_state { |
| 56 | int num; |
| 57 | |
| 58 | struct list_head node; |
| 59 | struct omap_hwmod *oh; |
| 60 | struct omap_device_pad default_omap_uart_pads[2]; |
| 61 | }; |
| 62 | |
| 63 | static LIST_HEAD(uart_list); |
| 64 | static u8 num_uarts; |
| 65 | static u8 console_uart_id = -1; |
| 66 | static u8 no_console_suspend; |
| 67 | static u8 uart_debug; |
| 68 | |
| 69 | #define DEFAULT_RXDMA_POLLRATE 1 /* RX DMA polling rate (us) */ |
| 70 | #define DEFAULT_RXDMA_BUFSIZE 4096 /* RX DMA buffer size */ |
| 71 | #define DEFAULT_RXDMA_TIMEOUT (3 * HZ)/* RX DMA timeout (jiffies) */ |
| 72 | |
| 73 | static struct omap_uart_port_info omap_serial_default_info[] __initdata = { |
| 74 | { |
| 75 | .dma_enabled = false, |
| 76 | .dma_rx_buf_size = DEFAULT_RXDMA_BUFSIZE, |
| 77 | .dma_rx_poll_rate = DEFAULT_RXDMA_POLLRATE, |
| 78 | .dma_rx_timeout = DEFAULT_RXDMA_TIMEOUT, |
| 79 | .autosuspend_timeout = DEFAULT_AUTOSUSPEND_DELAY, |
| 80 | }, |
| 81 | }; |
| 82 | |
| 83 | #ifdef CONFIG_PM |
| 84 | static void omap_uart_enable_wakeup(struct device *dev, bool enable) |
| 85 | { |
| 86 | struct platform_device *pdev = to_platform_device(dev); |
| 87 | struct omap_device *od = to_omap_device(pdev); |
| 88 | |
| 89 | if (!od) |
| 90 | return; |
| 91 | |
| 92 | if (enable) |
| 93 | omap_hwmod_enable_wakeup(od->hwmods[0]); |
| 94 | else |
| 95 | omap_hwmod_disable_wakeup(od->hwmods[0]); |
| 96 | } |
| 97 | |
| 98 | /* |
| 99 | * Errata i291: [UART]:Cannot Acknowledge Idle Requests |
| 100 | * in Smartidle Mode When Configured for DMA Operations. |
| 101 | * WA: configure uart in force idle mode. |
| 102 | */ |
| 103 | static void omap_uart_set_noidle(struct device *dev) |
| 104 | { |
| 105 | struct platform_device *pdev = to_platform_device(dev); |
| 106 | struct omap_device *od = to_omap_device(pdev); |
| 107 | |
| 108 | omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_NO); |
| 109 | } |
| 110 | |
| 111 | static void omap_uart_set_smartidle(struct device *dev) |
| 112 | { |
| 113 | struct platform_device *pdev = to_platform_device(dev); |
| 114 | struct omap_device *od = to_omap_device(pdev); |
| 115 | u8 idlemode; |
| 116 | |
| 117 | if (od->hwmods[0]->class->sysc->idlemodes & SIDLE_SMART_WKUP) |
| 118 | idlemode = HWMOD_IDLEMODE_SMART_WKUP; |
| 119 | else |
| 120 | idlemode = HWMOD_IDLEMODE_SMART; |
| 121 | |
| 122 | omap_hwmod_set_slave_idlemode(od->hwmods[0], idlemode); |
| 123 | } |
| 124 | |
| 125 | #else |
| 126 | static void omap_uart_enable_wakeup(struct device *dev, bool enable) |
| 127 | {} |
| 128 | static void omap_uart_set_noidle(struct device *dev) {} |
| 129 | static void omap_uart_set_smartidle(struct device *dev) {} |
| 130 | #endif /* CONFIG_PM */ |
| 131 | |
| 132 | #ifdef CONFIG_OMAP_MUX |
| 133 | |
| 134 | #define OMAP_UART_DEFAULT_PAD_NAME_LEN 28 |
| 135 | static char rx_pad_name[OMAP_UART_DEFAULT_PAD_NAME_LEN], |
| 136 | tx_pad_name[OMAP_UART_DEFAULT_PAD_NAME_LEN] __initdata; |
| 137 | |
| 138 | static void __init |
| 139 | omap_serial_fill_uart_tx_rx_pads(struct omap_board_data *bdata, |
| 140 | struct omap_uart_state *uart) |
| 141 | { |
| 142 | uart->default_omap_uart_pads[0].name = rx_pad_name; |
| 143 | uart->default_omap_uart_pads[0].flags = OMAP_DEVICE_PAD_REMUX | |
| 144 | OMAP_DEVICE_PAD_WAKEUP; |
| 145 | uart->default_omap_uart_pads[0].enable = OMAP_PIN_INPUT | |
| 146 | OMAP_MUX_MODE0; |
| 147 | uart->default_omap_uart_pads[0].idle = OMAP_PIN_INPUT | OMAP_MUX_MODE0; |
| 148 | uart->default_omap_uart_pads[1].name = tx_pad_name; |
| 149 | uart->default_omap_uart_pads[1].enable = OMAP_PIN_OUTPUT | |
| 150 | OMAP_MUX_MODE0; |
| 151 | bdata->pads = uart->default_omap_uart_pads; |
| 152 | bdata->pads_cnt = ARRAY_SIZE(uart->default_omap_uart_pads); |
| 153 | } |
| 154 | |
| 155 | static void __init omap_serial_check_wakeup(struct omap_board_data *bdata, |
| 156 | struct omap_uart_state *uart) |
| 157 | { |
| 158 | struct omap_mux_partition *tx_partition = NULL, *rx_partition = NULL; |
| 159 | struct omap_mux *rx_mux = NULL, *tx_mux = NULL; |
| 160 | char *rx_fmt, *tx_fmt; |
| 161 | int uart_nr = bdata->id + 1; |
| 162 | |
| 163 | if (bdata->id != 2) { |
| 164 | rx_fmt = "uart%d_rx.uart%d_rx"; |
| 165 | tx_fmt = "uart%d_tx.uart%d_tx"; |
| 166 | } else { |
| 167 | rx_fmt = "uart%d_rx_irrx.uart%d_rx_irrx"; |
| 168 | tx_fmt = "uart%d_tx_irtx.uart%d_tx_irtx"; |
| 169 | } |
| 170 | |
| 171 | snprintf(rx_pad_name, OMAP_UART_DEFAULT_PAD_NAME_LEN, rx_fmt, |
| 172 | uart_nr, uart_nr); |
| 173 | snprintf(tx_pad_name, OMAP_UART_DEFAULT_PAD_NAME_LEN, tx_fmt, |
| 174 | uart_nr, uart_nr); |
| 175 | |
| 176 | if (omap_mux_get_by_name(rx_pad_name, &rx_partition, &rx_mux) >= 0 && |
| 177 | omap_mux_get_by_name |
| 178 | (tx_pad_name, &tx_partition, &tx_mux) >= 0) { |
| 179 | u16 tx_mode, rx_mode; |
| 180 | |
| 181 | tx_mode = omap_mux_read(tx_partition, tx_mux->reg_offset); |
| 182 | rx_mode = omap_mux_read(rx_partition, rx_mux->reg_offset); |
| 183 | |
| 184 | /* |
| 185 | * Check if uart is used in default tx/rx mode i.e. in mux mode0 |
| 186 | * if yes then configure rx pin for wake up capability |
| 187 | */ |
| 188 | if (OMAP_MODE_UART(rx_mode) && OMAP_MODE_UART(tx_mode)) |
| 189 | omap_serial_fill_uart_tx_rx_pads(bdata, uart); |
| 190 | } |
| 191 | } |
| 192 | #else |
| 193 | static void __init omap_serial_check_wakeup(struct omap_board_data *bdata, |
| 194 | struct omap_uart_state *uart) |
| 195 | { |
| 196 | } |
| 197 | #endif |
| 198 | |
| 199 | static char *cmdline_find_option(char *str) |
| 200 | { |
| 201 | extern char *saved_command_line; |
| 202 | |
| 203 | return strstr(saved_command_line, str); |
| 204 | } |
| 205 | |
| 206 | static int __init omap_serial_early_init(void) |
| 207 | { |
| 208 | do { |
| 209 | char oh_name[MAX_UART_HWMOD_NAME_LEN]; |
| 210 | struct omap_hwmod *oh; |
| 211 | struct omap_uart_state *uart; |
| 212 | char uart_name[MAX_UART_HWMOD_NAME_LEN]; |
| 213 | |
| 214 | snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN, |
| 215 | "uart%d", num_uarts + 1); |
| 216 | oh = omap_hwmod_lookup(oh_name); |
| 217 | if (!oh) |
| 218 | break; |
| 219 | |
| 220 | uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL); |
| 221 | if (WARN_ON(!uart)) |
| 222 | return -ENODEV; |
| 223 | |
| 224 | uart->oh = oh; |
| 225 | uart->num = num_uarts++; |
| 226 | list_add_tail(&uart->node, &uart_list); |
| 227 | snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN, |
| 228 | "%s%d", OMAP_SERIAL_NAME, uart->num); |
| 229 | |
| 230 | if (cmdline_find_option(uart_name)) { |
| 231 | console_uart_id = uart->num; |
| 232 | |
| 233 | if (console_loglevel >= 10) { |
| 234 | uart_debug = true; |
| 235 | pr_info("%s used as console in debug mode: uart%d clocks will not be gated", |
| 236 | uart_name, uart->num); |
| 237 | } |
| 238 | |
| 239 | if (cmdline_find_option("no_console_suspend")) |
| 240 | no_console_suspend = true; |
| 241 | |
| 242 | /* |
| 243 | * omap-uart can be used for earlyprintk logs |
| 244 | * So if omap-uart is used as console then prevent |
| 245 | * uart reset and idle to get logs from omap-uart |
| 246 | * until uart console driver is available to take |
| 247 | * care for console messages. |
| 248 | * Idling or resetting omap-uart while printing logs |
| 249 | * early boot logs can stall the boot-up. |
| 250 | */ |
| 251 | oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET; |
| 252 | } |
| 253 | } while (1); |
| 254 | |
| 255 | return 0; |
| 256 | } |
| 257 | omap_core_initcall(omap_serial_early_init); |
| 258 | |
| 259 | /** |
| 260 | * omap_serial_init_port() - initialize single serial port |
| 261 | * @bdata: port specific board data pointer |
| 262 | * @info: platform specific data pointer |
| 263 | * |
| 264 | * This function initialies serial driver for given port only. |
| 265 | * Platforms can call this function instead of omap_serial_init() |
| 266 | * if they don't plan to use all available UARTs as serial ports. |
| 267 | * |
| 268 | * Don't mix calls to omap_serial_init_port() and omap_serial_init(), |
| 269 | * use only one of the two. |
| 270 | */ |
| 271 | void __init omap_serial_init_port(struct omap_board_data *bdata, |
| 272 | struct omap_uart_port_info *info) |
| 273 | { |
| 274 | struct omap_uart_state *uart; |
| 275 | struct omap_hwmod *oh; |
| 276 | struct platform_device *pdev; |
| 277 | void *pdata = NULL; |
| 278 | u32 pdata_size = 0; |
| 279 | char *name; |
| 280 | struct omap_uart_port_info omap_up; |
| 281 | |
| 282 | if (WARN_ON(!bdata)) |
| 283 | return; |
| 284 | if (WARN_ON(bdata->id < 0)) |
| 285 | return; |
| 286 | if (WARN_ON(bdata->id >= num_uarts)) |
| 287 | return; |
| 288 | |
| 289 | list_for_each_entry(uart, &uart_list, node) |
| 290 | if (bdata->id == uart->num) |
| 291 | break; |
| 292 | if (!info) |
| 293 | info = omap_serial_default_info; |
| 294 | |
| 295 | oh = uart->oh; |
| 296 | name = DRIVER_NAME; |
| 297 | |
| 298 | omap_up.dma_enabled = info->dma_enabled; |
| 299 | omap_up.uartclk = OMAP24XX_BASE_BAUD * 16; |
| 300 | omap_up.flags = UPF_BOOT_AUTOCONF; |
| 301 | omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count; |
| 302 | omap_up.set_forceidle = omap_uart_set_smartidle; |
| 303 | omap_up.set_noidle = omap_uart_set_noidle; |
| 304 | omap_up.enable_wakeup = omap_uart_enable_wakeup; |
| 305 | omap_up.dma_rx_buf_size = info->dma_rx_buf_size; |
| 306 | omap_up.dma_rx_timeout = info->dma_rx_timeout; |
| 307 | omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate; |
| 308 | omap_up.autosuspend_timeout = info->autosuspend_timeout; |
| 309 | omap_up.DTR_gpio = info->DTR_gpio; |
| 310 | omap_up.DTR_inverted = info->DTR_inverted; |
| 311 | omap_up.DTR_present = info->DTR_present; |
| 312 | |
| 313 | pdata = &omap_up; |
| 314 | pdata_size = sizeof(struct omap_uart_port_info); |
| 315 | |
| 316 | if (WARN_ON(!oh)) |
| 317 | return; |
| 318 | |
| 319 | pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size); |
| 320 | if (IS_ERR(pdev)) { |
| 321 | WARN(1, "Could not build omap_device for %s: %s.\n", name, |
| 322 | oh->name); |
| 323 | return; |
| 324 | } |
| 325 | |
| 326 | if ((console_uart_id == bdata->id) && no_console_suspend) |
| 327 | omap_device_disable_idle_on_suspend(pdev); |
| 328 | |
| 329 | oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt); |
| 330 | |
| 331 | if (console_uart_id == bdata->id) { |
| 332 | omap_device_enable(pdev); |
| 333 | pm_runtime_set_active(&pdev->dev); |
| 334 | } |
| 335 | |
| 336 | oh->dev_attr = uart; |
| 337 | |
| 338 | if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads) |
| 339 | && !uart_debug) |
| 340 | device_init_wakeup(&pdev->dev, true); |
| 341 | } |
| 342 | |
| 343 | /** |
| 344 | * omap_serial_board_init() - initialize all supported serial ports |
| 345 | * @info: platform specific data pointer |
| 346 | * |
| 347 | * Initializes all available UARTs as serial ports. Platforms |
| 348 | * can call this function when they want to have default behaviour |
| 349 | * for serial ports (e.g initialize them all as serial ports). |
| 350 | */ |
| 351 | void __init omap_serial_board_init(struct omap_uart_port_info *info) |
| 352 | { |
| 353 | struct omap_uart_state *uart; |
| 354 | struct omap_board_data bdata; |
| 355 | |
| 356 | list_for_each_entry(uart, &uart_list, node) { |
| 357 | bdata.id = uart->num; |
| 358 | bdata.flags = 0; |
| 359 | bdata.pads = NULL; |
| 360 | bdata.pads_cnt = 0; |
| 361 | |
| 362 | omap_serial_check_wakeup(&bdata, uart); |
| 363 | |
| 364 | if (!info) |
| 365 | omap_serial_init_port(&bdata, NULL); |
| 366 | else |
| 367 | omap_serial_init_port(&bdata, &info[uart->num]); |
| 368 | } |
| 369 | } |
| 370 | |
| 371 | /** |
| 372 | * omap_serial_init() - initialize all supported serial ports |
| 373 | * |
| 374 | * Initializes all available UARTs. |
| 375 | * Platforms can call this function when they want to have default behaviour |
| 376 | * for serial ports (e.g initialize them all as serial ports). |
| 377 | */ |
| 378 | void __init omap_serial_init(void) |
| 379 | { |
| 380 | omap_serial_board_init(NULL); |
| 381 | } |