arch/arm/mach-omap2/serial.c

   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
  30 #include <plat/omap-serial.h>
  31 #include "common.h"
  32 #include <plat/board.h>
  33 #include <plat/dma.h>
  34 #include <plat/omap_hwmod.h>
  35 #include <plat/omap_device.h>
  36 #include <plat/omap-pm.h>
  37
  38 #include "prm2xxx_3xxx.h"
  39 #include "pm.h"
  40 #include "cm2xxx_3xxx.h"
  41 #include "prm-regbits-34xx.h"
  42 #include "control.h"
  43 #include "mux.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         int can_sleep;
  58
  59         struct list_head node;
  60         struct omap_hwmod *oh;
  61         struct platform_device *pdev;
  62 };
  63
  64 static LIST_HEAD(uart_list);
  65 static u8 num_uarts;
  66 static u8 console_uart_id = -1;
  67 static u8 no_console_suspend;
  68 static u8 uart_debug;
  69
  70 #define DEFAULT_RXDMA_POLLRATE          1       /* RX DMA polling rate (us) */
  71 #define DEFAULT_RXDMA_BUFSIZE           4096    /* RX DMA buffer size */
  72 #define DEFAULT_RXDMA_TIMEOUT           (3 * HZ)/* RX DMA timeout (jiffies) */
  73
  74 static struct omap_uart_port_info omap_serial_default_info[] __initdata = {
  75         {
  76                 .dma_enabled    = false,
  77                 .dma_rx_buf_size = DEFAULT_RXDMA_BUFSIZE,
  78                 .dma_rx_poll_rate = DEFAULT_RXDMA_POLLRATE,
  79                 .dma_rx_timeout = DEFAULT_RXDMA_TIMEOUT,
  80                 .autosuspend_timeout = DEFAULT_AUTOSUSPEND_DELAY,
  81         },
  82 };
  83
  84 #ifdef CONFIG_PM
  85 static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
  86 {
  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 platform_device *pdev)
 104 {
 105         struct omap_device *od = to_omap_device(pdev);
 106
 107         omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_NO);
 108 }
 109
 110 static void omap_uart_set_smartidle(struct platform_device *pdev)
 111 {
 112         struct omap_device *od = to_omap_device(pdev);
 113
 114         omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_SMART);
 115 }
 116
 117 #else
 118 static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
 119 {}
 120 static void omap_uart_set_noidle(struct platform_device *pdev) {}
 121 static void omap_uart_set_smartidle(struct platform_device *pdev) {}
 122 #endif /* CONFIG_PM */
 123
 124 #ifdef CONFIG_OMAP_MUX
 125 static struct omap_device_pad default_uart1_pads[] __initdata = {
 126         {
 127                 .name   = "uart1_cts.uart1_cts",
 128                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 129         },
 130         {
 131                 .name   = "uart1_rts.uart1_rts",
 132                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 133         },
 134         {
 135                 .name   = "uart1_tx.uart1_tx",
 136                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 137         },
 138         {
 139                 .name   = "uart1_rx.uart1_rx",
 140                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 141                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 142                 .idle   = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 143         },
 144 };
 145
 146 static struct omap_device_pad default_uart2_pads[] __initdata = {
 147         {
 148                 .name   = "uart2_cts.uart2_cts",
 149                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 150         },
 151         {
 152                 .name   = "uart2_rts.uart2_rts",
 153                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 154         },
 155         {
 156                 .name   = "uart2_tx.uart2_tx",
 157                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 158         },
 159         {
 160                 .name   = "uart2_rx.uart2_rx",
 161                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 162                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 163                 .idle   = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 164         },
 165 };
 166
 167 static struct omap_device_pad default_uart3_pads[] __initdata = {
 168         {
 169                 .name   = "uart3_cts_rctx.uart3_cts_rctx",
 170                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 171         },
 172         {
 173                 .name   = "uart3_rts_sd.uart3_rts_sd",
 174                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 175         },
 176         {
 177                 .name   = "uart3_tx_irtx.uart3_tx_irtx",
 178                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 179         },
 180         {
 181                 .name   = "uart3_rx_irrx.uart3_rx_irrx",
 182                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 183                 .enable = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 184                 .idle   = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 185         },
 186 };
 187
 188 static struct omap_device_pad default_omap36xx_uart4_pads[] __initdata = {
 189         {
 190                 .name   = "gpmc_wait2.uart4_tx",
 191                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 192         },
 193         {
 194                 .name   = "gpmc_wait3.uart4_rx",
 195                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 196                 .enable = OMAP_PIN_INPUT | OMAP_MUX_MODE2,
 197                 .idle   = OMAP_PIN_INPUT | OMAP_MUX_MODE2,
 198         },
 199 };
 200
 201 static struct omap_device_pad default_omap4_uart4_pads[] __initdata = {
 202         {
 203                 .name   = "uart4_tx.uart4_tx",
 204                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 205         },
 206         {
 207                 .name   = "uart4_rx.uart4_rx",
 208                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 209                 .enable = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 210                 .idle   = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 211         },
 212 };
 213
 214 static void omap_serial_fill_default_pads(struct omap_board_data *bdata)
 215 {
 216         switch (bdata->id) {
 217         case 0:
 218                 bdata->pads = default_uart1_pads;
 219                 bdata->pads_cnt = ARRAY_SIZE(default_uart1_pads);
 220                 break;
 221         case 1:
 222                 bdata->pads = default_uart2_pads;
 223                 bdata->pads_cnt = ARRAY_SIZE(default_uart2_pads);
 224                 break;
 225         case 2:
 226                 bdata->pads = default_uart3_pads;
 227                 bdata->pads_cnt = ARRAY_SIZE(default_uart3_pads);
 228                 break;
 229         case 3:
 230                 if (cpu_is_omap44xx()) {
 231                         bdata->pads = default_omap4_uart4_pads;
 232                         bdata->pads_cnt =
 233                                 ARRAY_SIZE(default_omap4_uart4_pads);
 234                 } else if (cpu_is_omap3630()) {
 235                         bdata->pads = default_omap36xx_uart4_pads;
 236                         bdata->pads_cnt =
 237                                 ARRAY_SIZE(default_omap36xx_uart4_pads);
 238                 }
 239                 break;
 240         default:
 241                 break;
 242         }
 243 }
 244 #else
 245 static void omap_serial_fill_default_pads(struct omap_board_data *bdata) {}
 246 #endif
 247
 248 char *cmdline_find_option(char *str)
 249 {
 250         extern char *saved_command_line;
 251
 252         return strstr(saved_command_line, str);
 253 }
 254
 255 static int __init omap_serial_early_init(void)
 256 {
 257         do {
 258                 char oh_name[MAX_UART_HWMOD_NAME_LEN];
 259                 struct omap_hwmod *oh;
 260                 struct omap_uart_state *uart;
 261                 char uart_name[MAX_UART_HWMOD_NAME_LEN];
 262
 263                 snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN,
 264                          "uart%d", num_uarts + 1);
 265                 oh = omap_hwmod_lookup(oh_name);
 266                 if (!oh)
 267                         break;
 268
 269                 uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL);
 270                 if (WARN_ON(!uart))
 271                         return -ENODEV;
 272
 273                 uart->oh = oh;
 274                 uart->num = num_uarts++;
 275                 list_add_tail(&uart->node, &uart_list);
 276                 snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN,
 277                                 "%s%d", OMAP_SERIAL_NAME, uart->num);
 278
 279                 if (cmdline_find_option(uart_name)) {
 280                         console_uart_id = uart->num;
 281
 282                         if (console_loglevel >= 10) {
 283                                 uart_debug = true;
 284                                 pr_info("%s used as console in debug mode"
 285                                                 " uart%d clocks will not be"
 286                                                 " gated", uart_name, uart->num);
 287                         }
 288
 289                         if (cmdline_find_option("no_console_suspend"))
 290                                 no_console_suspend = true;
 291
 292                         /*
 293                          * omap-uart can be used for earlyprintk logs
 294                          * So if omap-uart is used as console then prevent
 295                          * uart reset and idle to get logs from omap-uart
 296                          * until uart console driver is available to take
 297                          * care for console messages.
 298                          * Idling or resetting omap-uart while printing logs
 299                          * early boot logs can stall the boot-up.
 300                          */
 301                         oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET;
 302                 }
 303         } while (1);
 304
 305         return 0;
 306 }
 307 core_initcall(omap_serial_early_init);
 308
 309 /**
 310  * omap_serial_init_port() - initialize single serial port
 311  * @bdata: port specific board data pointer
 312  * @info: platform specific data pointer
 313  *
 314  * This function initialies serial driver for given port only.
 315  * Platforms can call this function instead of omap_serial_init()
 316  * if they don't plan to use all available UARTs as serial ports.
 317  *
 318  * Don't mix calls to omap_serial_init_port() and omap_serial_init(),
 319  * use only one of the two.
 320  */
 321 void __init omap_serial_init_port(struct omap_board_data *bdata,
 322                         struct omap_uart_port_info *info)
 323 {
 324         struct omap_uart_state *uart;
 325         struct omap_hwmod *oh;
 326         struct platform_device *pdev;
 327         void *pdata = NULL;
 328         u32 pdata_size = 0;
 329         char *name;
 330         struct omap_uart_port_info omap_up;
 331
 332         if (WARN_ON(!bdata))
 333                 return;
 334         if (WARN_ON(bdata->id < 0))
 335                 return;
 336         if (WARN_ON(bdata->id >= num_uarts))
 337                 return;
 338
 339         list_for_each_entry(uart, &uart_list, node)
 340                 if (bdata->id == uart->num)
 341                         break;
 342         if (!info)
 343                 info = omap_serial_default_info;
 344
 345         oh = uart->oh;
 346         name = DRIVER_NAME;
 347
 348         omap_up.dma_enabled = info->dma_enabled;
 349         omap_up.uartclk = OMAP24XX_BASE_BAUD * 16;
 350         omap_up.flags = UPF_BOOT_AUTOCONF;
 351         omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count;
 352         omap_up.set_forceidle = omap_uart_set_smartidle;
 353         omap_up.set_noidle = omap_uart_set_noidle;
 354         omap_up.enable_wakeup = omap_uart_enable_wakeup;
 355         omap_up.dma_rx_buf_size = info->dma_rx_buf_size;
 356         omap_up.dma_rx_timeout = info->dma_rx_timeout;
 357         omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate;
 358         omap_up.autosuspend_timeout = info->autosuspend_timeout;
 359
 360         /* Enable the MDR1 Errata i202 for OMAP2430/3xxx/44xx */
 361         if (!cpu_is_omap2420() && !cpu_is_ti816x())
 362                 omap_up.errata |= UART_ERRATA_i202_MDR1_ACCESS;
 363
 364         /* Enable DMA Mode Force Idle Errata i291 for omap34xx/3630 */
 365         if (cpu_is_omap34xx() || cpu_is_omap3630())
 366                 omap_up.errata |= UART_ERRATA_i291_DMA_FORCEIDLE;
 367
 368         pdata = &omap_up;
 369         pdata_size = sizeof(struct omap_uart_port_info);
 370
 371         if (WARN_ON(!oh))
 372                 return;
 373
 374         pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size,
 375                                  NULL, 0, false);
 376         WARN(IS_ERR(pdev), "Could not build omap_device for %s: %s.\n",
 377              name, oh->name);
 378
 379         if ((console_uart_id == bdata->id) && no_console_suspend)
 380                 omap_device_disable_idle_on_suspend(pdev);
 381
 382         oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt);
 383
 384         uart->pdev = pdev;
 385
 386         oh->dev_attr = uart;
 387
 388         if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
 389                         && !uart_debug)
 390                 device_init_wakeup(&pdev->dev, true);
 391 }
 392
 393 /**
 394  * omap_serial_board_init() - initialize all supported serial ports
 395  * @info: platform specific data pointer
 396  *
 397  * Initializes all available UARTs as serial ports. Platforms
 398  * can call this function when they want to have default behaviour
 399  * for serial ports (e.g initialize them all as serial ports).
 400  */
 401 void __init omap_serial_board_init(struct omap_uart_port_info *info)
 402 {
 403         struct omap_uart_state *uart;
 404         struct omap_board_data bdata;
 405
 406         list_for_each_entry(uart, &uart_list, node) {
 407                 bdata.id = uart->num;
 408                 bdata.flags = 0;
 409                 bdata.pads = NULL;
 410                 bdata.pads_cnt = 0;
 411
 412                 if (cpu_is_omap44xx() || cpu_is_omap34xx())
 413                         omap_serial_fill_default_pads(&bdata);
 414
 415                 if (!info)
 416                         omap_serial_init_port(&bdata, NULL);
 417                 else
 418                         omap_serial_init_port(&bdata, &info[uart->num]);
 419         }
 420 }
 421
 422 /**
 423  * omap_serial_init() - initialize all supported serial ports
 424  *
 425  * Initializes all available UARTs.
 426  * Platforms can call this function when they want to have default behaviour
 427  * for serial ports (e.g initialize them all as serial ports).
 428  */
 429 void __init omap_serial_init(void)
 430 {
 431         omap_serial_board_init(NULL);
 432 }