Pileus Git - ~andy/linux/blob - 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
  58         struct list_head node;
  59         struct omap_hwmod *oh;
  60 };
  61
  62 static LIST_HEAD(uart_list);
  63 static u8 num_uarts;
  64 static u8 console_uart_id = -1;
  65 static u8 no_console_suspend;
  66 static u8 uart_debug;
  67
  68 #define DEFAULT_RXDMA_POLLRATE          1       /* RX DMA polling rate (us) */
  69 #define DEFAULT_RXDMA_BUFSIZE           4096    /* RX DMA buffer size */
  70 #define DEFAULT_RXDMA_TIMEOUT           (3 * HZ)/* RX DMA timeout (jiffies) */
  71
  72 static struct omap_uart_port_info omap_serial_default_info[] __initdata = {
  73         {
  74                 .dma_enabled    = false,
  75                 .dma_rx_buf_size = DEFAULT_RXDMA_BUFSIZE,
  76                 .dma_rx_poll_rate = DEFAULT_RXDMA_POLLRATE,
  77                 .dma_rx_timeout = DEFAULT_RXDMA_TIMEOUT,
  78                 .autosuspend_timeout = DEFAULT_AUTOSUSPEND_DELAY,
  79         },
  80 };
  81
  82 #ifdef CONFIG_PM
  83 static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
  84 {
  85         struct omap_device *od = to_omap_device(pdev);
  86
  87         if (!od)
  88                 return;
  89
  90         if (enable)
  91                 omap_hwmod_enable_wakeup(od->hwmods[0]);
  92         else
  93                 omap_hwmod_disable_wakeup(od->hwmods[0]);
  94 }
  95
  96 /*
  97  * Errata i291: [UART]:Cannot Acknowledge Idle Requests
  98  * in Smartidle Mode When Configured for DMA Operations.
  99  * WA: configure uart in force idle mode.
 100  */
 101 static void omap_uart_set_noidle(struct platform_device *pdev)
 102 {
 103         struct omap_device *od = to_omap_device(pdev);
 104
 105         omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_NO);
 106 }
 107
 108 static void omap_uart_set_smartidle(struct platform_device *pdev)
 109 {
 110         struct omap_device *od = to_omap_device(pdev);
 111
 112         omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_SMART);
 113 }
 114
 115 #else
 116 static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
 117 {}
 118 static void omap_uart_set_noidle(struct platform_device *pdev) {}
 119 static void omap_uart_set_smartidle(struct platform_device *pdev) {}
 120 #endif /* CONFIG_PM */
 121
 122 #ifdef CONFIG_OMAP_MUX
 123 static struct omap_device_pad default_uart1_pads[] __initdata = {
 124         {
 125                 .name   = "uart1_cts.uart1_cts",
 126                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 127         },
 128         {
 129                 .name   = "uart1_rts.uart1_rts",
 130                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 131         },
 132         {
 133                 .name   = "uart1_tx.uart1_tx",
 134                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 135         },
 136         {
 137                 .name   = "uart1_rx.uart1_rx",
 138                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 139                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 140                 .idle   = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 141         },
 142 };
 143
 144 static struct omap_device_pad default_uart2_pads[] __initdata = {
 145         {
 146                 .name   = "uart2_cts.uart2_cts",
 147                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 148         },
 149         {
 150                 .name   = "uart2_rts.uart2_rts",
 151                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 152         },
 153         {
 154                 .name   = "uart2_tx.uart2_tx",
 155                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 156         },
 157         {
 158                 .name   = "uart2_rx.uart2_rx",
 159                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 160                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 161                 .idle   = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 162         },
 163 };
 164
 165 static struct omap_device_pad default_uart3_pads[] __initdata = {
 166         {
 167                 .name   = "uart3_cts_rctx.uart3_cts_rctx",
 168                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 169         },
 170         {
 171                 .name   = "uart3_rts_sd.uart3_rts_sd",
 172                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 173         },
 174         {
 175                 .name   = "uart3_tx_irtx.uart3_tx_irtx",
 176                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 177         },
 178         {
 179                 .name   = "uart3_rx_irrx.uart3_rx_irrx",
 180                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 181                 .enable = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 182                 .idle   = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 183         },
 184 };
 185
 186 static struct omap_device_pad default_omap36xx_uart4_pads[] __initdata = {
 187         {
 188                 .name   = "gpmc_wait2.uart4_tx",
 189                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 190         },
 191         {
 192                 .name   = "gpmc_wait3.uart4_rx",
 193                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 194                 .enable = OMAP_PIN_INPUT | OMAP_MUX_MODE2,
 195                 .idle   = OMAP_PIN_INPUT | OMAP_MUX_MODE2,
 196         },
 197 };
 198
 199 static struct omap_device_pad default_omap4_uart4_pads[] __initdata = {
 200         {
 201                 .name   = "uart4_tx.uart4_tx",
 202                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 203         },
 204         {
 205                 .name   = "uart4_rx.uart4_rx",
 206                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 207                 .enable = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 208                 .idle   = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 209         },
 210 };
 211
 212 static void omap_serial_fill_default_pads(struct omap_board_data *bdata)
 213 {
 214         switch (bdata->id) {
 215         case 0:
 216                 bdata->pads = default_uart1_pads;
 217                 bdata->pads_cnt = ARRAY_SIZE(default_uart1_pads);
 218                 break;
 219         case 1:
 220                 bdata->pads = default_uart2_pads;
 221                 bdata->pads_cnt = ARRAY_SIZE(default_uart2_pads);
 222                 break;
 223         case 2:
 224                 bdata->pads = default_uart3_pads;
 225                 bdata->pads_cnt = ARRAY_SIZE(default_uart3_pads);
 226                 break;
 227         case 3:
 228                 if (cpu_is_omap44xx()) {
 229                         bdata->pads = default_omap4_uart4_pads;
 230                         bdata->pads_cnt =
 231                                 ARRAY_SIZE(default_omap4_uart4_pads);
 232                 } else if (cpu_is_omap3630()) {
 233                         bdata->pads = default_omap36xx_uart4_pads;
 234                         bdata->pads_cnt =
 235                                 ARRAY_SIZE(default_omap36xx_uart4_pads);
 236                 }
 237                 break;
 238         default:
 239                 break;
 240         }
 241 }
 242 #else
 243 static void omap_serial_fill_default_pads(struct omap_board_data *bdata) {}
 244 #endif
 245
 246 char *cmdline_find_option(char *str)
 247 {
 248         extern char *saved_command_line;
 249
 250         return strstr(saved_command_line, str);
 251 }
 252
 253 static int __init omap_serial_early_init(void)
 254 {
 255         do {
 256                 char oh_name[MAX_UART_HWMOD_NAME_LEN];
 257                 struct omap_hwmod *oh;
 258                 struct omap_uart_state *uart;
 259                 char uart_name[MAX_UART_HWMOD_NAME_LEN];
 260
 261                 snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN,
 262                          "uart%d", num_uarts + 1);
 263                 oh = omap_hwmod_lookup(oh_name);
 264                 if (!oh)
 265                         break;
 266
 267                 uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL);
 268                 if (WARN_ON(!uart))
 269                         return -ENODEV;
 270
 271                 uart->oh = oh;
 272                 uart->num = num_uarts++;
 273                 list_add_tail(&uart->node, &uart_list);
 274                 snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN,
 275                                 "%s%d", OMAP_SERIAL_NAME, uart->num);
 276
 277                 if (cmdline_find_option(uart_name)) {
 278                         console_uart_id = uart->num;
 279
 280                         if (console_loglevel >= 10) {
 281                                 uart_debug = true;
 282                                 pr_info("%s used as console in debug mode"
 283                                                 " uart%d clocks will not be"
 284                                                 " gated", uart_name, uart->num);
 285                         }
 286
 287                         if (cmdline_find_option("no_console_suspend"))
 288                                 no_console_suspend = true;
 289
 290                         /*
 291                          * omap-uart can be used for earlyprintk logs
 292                          * So if omap-uart is used as console then prevent
 293                          * uart reset and idle to get logs from omap-uart
 294                          * until uart console driver is available to take
 295                          * care for console messages.
 296                          * Idling or resetting omap-uart while printing logs
 297                          * early boot logs can stall the boot-up.
 298                          */
 299                         oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET;
 300                 }
 301         } while (1);
 302
 303         return 0;
 304 }
 305 core_initcall(omap_serial_early_init);
 306
 307 /**
 308  * omap_serial_init_port() - initialize single serial port
 309  * @bdata: port specific board data pointer
 310  * @info: platform specific data pointer
 311  *
 312  * This function initialies serial driver for given port only.
 313  * Platforms can call this function instead of omap_serial_init()
 314  * if they don't plan to use all available UARTs as serial ports.
 315  *
 316  * Don't mix calls to omap_serial_init_port() and omap_serial_init(),
 317  * use only one of the two.
 318  */
 319 void __init omap_serial_init_port(struct omap_board_data *bdata,
 320                         struct omap_uart_port_info *info)
 321 {
 322         struct omap_uart_state *uart;
 323         struct omap_hwmod *oh;
 324         struct platform_device *pdev;
 325         void *pdata = NULL;
 326         u32 pdata_size = 0;
 327         char *name;
 328         struct omap_uart_port_info omap_up;
 329
 330         if (WARN_ON(!bdata))
 331                 return;
 332         if (WARN_ON(bdata->id < 0))
 333                 return;
 334         if (WARN_ON(bdata->id >= num_uarts))
 335                 return;
 336
 337         list_for_each_entry(uart, &uart_list, node)
 338                 if (bdata->id == uart->num)
 339                         break;
 340         if (!info)
 341                 info = omap_serial_default_info;
 342
 343         oh = uart->oh;
 344         name = DRIVER_NAME;
 345
 346         omap_up.dma_enabled = info->dma_enabled;
 347         omap_up.uartclk = OMAP24XX_BASE_BAUD * 16;
 348         omap_up.flags = UPF_BOOT_AUTOCONF;
 349         omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count;
 350         omap_up.set_forceidle = omap_uart_set_smartidle;
 351         omap_up.set_noidle = omap_uart_set_noidle;
 352         omap_up.enable_wakeup = omap_uart_enable_wakeup;
 353         omap_up.dma_rx_buf_size = info->dma_rx_buf_size;
 354         omap_up.dma_rx_timeout = info->dma_rx_timeout;
 355         omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate;
 356         omap_up.autosuspend_timeout = info->autosuspend_timeout;
 357
 358         /* Enable the MDR1 Errata i202 for OMAP2430/3xxx/44xx */
 359         if (!cpu_is_omap2420() && !cpu_is_ti816x())
 360                 omap_up.errata |= UART_ERRATA_i202_MDR1_ACCESS;
 361
 362         /* Enable DMA Mode Force Idle Errata i291 for omap34xx/3630 */
 363         if (cpu_is_omap34xx() || cpu_is_omap3630())
 364                 omap_up.errata |= UART_ERRATA_i291_DMA_FORCEIDLE;
 365
 366         pdata = &omap_up;
 367         pdata_size = sizeof(struct omap_uart_port_info);
 368
 369         if (WARN_ON(!oh))
 370                 return;
 371
 372         pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size,
 373                                  NULL, 0, false);
 374         WARN(IS_ERR(pdev), "Could not build omap_device for %s: %s.\n",
 375              name, oh->name);
 376
 377         if ((console_uart_id == bdata->id) && no_console_suspend)
 378                 omap_device_disable_idle_on_suspend(pdev);
 379
 380         oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt);
 381
 382         oh->dev_attr = uart;
 383
 384         if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
 385                         && !uart_debug)
 386                 device_init_wakeup(&pdev->dev, true);
 387 }
 388
 389 /**
 390  * omap_serial_board_init() - initialize all supported serial ports
 391  * @info: platform specific data pointer
 392  *
 393  * Initializes all available UARTs as serial ports. Platforms
 394  * can call this function when they want to have default behaviour
 395  * for serial ports (e.g initialize them all as serial ports).
 396  */
 397 void __init omap_serial_board_init(struct omap_uart_port_info *info)
 398 {
 399         struct omap_uart_state *uart;
 400         struct omap_board_data bdata;
 401
 402         list_for_each_entry(uart, &uart_list, node) {
 403                 bdata.id = uart->num;
 404                 bdata.flags = 0;
 405                 bdata.pads = NULL;
 406                 bdata.pads_cnt = 0;
 407
 408                 if (cpu_is_omap44xx() || cpu_is_omap34xx())
 409                         omap_serial_fill_default_pads(&bdata);
 410
 411                 if (!info)
 412                         omap_serial_init_port(&bdata, NULL);
 413                 else
 414                         omap_serial_init_port(&bdata, &info[uart->num]);
 415         }
 416 }
 417
 418 /**
 419  * omap_serial_init() - initialize all supported serial ports
 420  *
 421  * Initializes all available UARTs.
 422  * Platforms can call this function when they want to have default behaviour
 423  * for serial ports (e.g initialize them all as serial ports).
 424  */
 425 void __init omap_serial_init(void)
 426 {
 427         omap_serial_board_init(NULL);
 428 }