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         u8 idlemode;
 114
 115         if (od->hwmods[0]->class->sysc->idlemodes & SIDLE_SMART_WKUP)
 116                 idlemode = HWMOD_IDLEMODE_SMART_WKUP;
 117         else
 118                 idlemode = HWMOD_IDLEMODE_SMART;
 119
 120         omap_hwmod_set_slave_idlemode(od->hwmods[0], idlemode);
 121 }
 122
 123 #else
 124 static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
 125 {}
 126 static void omap_uart_set_noidle(struct platform_device *pdev) {}
 127 static void omap_uart_set_smartidle(struct platform_device *pdev) {}
 128 #endif /* CONFIG_PM */
 129
 130 #ifdef CONFIG_OMAP_MUX
 131 static struct omap_device_pad default_uart1_pads[] __initdata = {
 132         {
 133                 .name   = "uart1_cts.uart1_cts",
 134                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 135         },
 136         {
 137                 .name   = "uart1_rts.uart1_rts",
 138                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 139         },
 140         {
 141                 .name   = "uart1_tx.uart1_tx",
 142                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 143         },
 144         {
 145                 .name   = "uart1_rx.uart1_rx",
 146                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 147                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 148                 .idle   = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 149         },
 150 };
 151
 152 static struct omap_device_pad default_uart2_pads[] __initdata = {
 153         {
 154                 .name   = "uart2_cts.uart2_cts",
 155                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 156         },
 157         {
 158                 .name   = "uart2_rts.uart2_rts",
 159                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 160         },
 161         {
 162                 .name   = "uart2_tx.uart2_tx",
 163                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 164         },
 165         {
 166                 .name   = "uart2_rx.uart2_rx",
 167                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 168                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 169                 .idle   = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 170         },
 171 };
 172
 173 static struct omap_device_pad default_uart3_pads[] __initdata = {
 174         {
 175                 .name   = "uart3_cts_rctx.uart3_cts_rctx",
 176                 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
 177         },
 178         {
 179                 .name   = "uart3_rts_sd.uart3_rts_sd",
 180                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 181         },
 182         {
 183                 .name   = "uart3_tx_irtx.uart3_tx_irtx",
 184                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 185         },
 186         {
 187                 .name   = "uart3_rx_irrx.uart3_rx_irrx",
 188                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 189                 .enable = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 190                 .idle   = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 191         },
 192 };
 193
 194 static struct omap_device_pad default_omap36xx_uart4_pads[] __initdata = {
 195         {
 196                 .name   = "gpmc_wait2.uart4_tx",
 197                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 198         },
 199         {
 200                 .name   = "gpmc_wait3.uart4_rx",
 201                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 202                 .enable = OMAP_PIN_INPUT | OMAP_MUX_MODE2,
 203                 .idle   = OMAP_PIN_INPUT | OMAP_MUX_MODE2,
 204         },
 205 };
 206
 207 static struct omap_device_pad default_omap4_uart4_pads[] __initdata = {
 208         {
 209                 .name   = "uart4_tx.uart4_tx",
 210                 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
 211         },
 212         {
 213                 .name   = "uart4_rx.uart4_rx",
 214                 .flags  = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
 215                 .enable = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 216                 .idle   = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
 217         },
 218 };
 219
 220 static void omap_serial_fill_default_pads(struct omap_board_data *bdata)
 221 {
 222         switch (bdata->id) {
 223         case 0:
 224                 bdata->pads = default_uart1_pads;
 225                 bdata->pads_cnt = ARRAY_SIZE(default_uart1_pads);
 226                 break;
 227         case 1:
 228                 bdata->pads = default_uart2_pads;
 229                 bdata->pads_cnt = ARRAY_SIZE(default_uart2_pads);
 230                 break;
 231         case 2:
 232                 bdata->pads = default_uart3_pads;
 233                 bdata->pads_cnt = ARRAY_SIZE(default_uart3_pads);
 234                 break;
 235         case 3:
 236                 if (cpu_is_omap44xx()) {
 237                         bdata->pads = default_omap4_uart4_pads;
 238                         bdata->pads_cnt =
 239                                 ARRAY_SIZE(default_omap4_uart4_pads);
 240                 } else if (cpu_is_omap3630()) {
 241                         bdata->pads = default_omap36xx_uart4_pads;
 242                         bdata->pads_cnt =
 243                                 ARRAY_SIZE(default_omap36xx_uart4_pads);
 244                 }
 245                 break;
 246         default:
 247                 break;
 248         }
 249 }
 250 #else
 251 static void omap_serial_fill_default_pads(struct omap_board_data *bdata) {}
 252 #endif
 253
 254 char *cmdline_find_option(char *str)
 255 {
 256         extern char *saved_command_line;
 257
 258         return strstr(saved_command_line, str);
 259 }
 260
 261 static int __init omap_serial_early_init(void)
 262 {
 263         do {
 264                 char oh_name[MAX_UART_HWMOD_NAME_LEN];
 265                 struct omap_hwmod *oh;
 266                 struct omap_uart_state *uart;
 267                 char uart_name[MAX_UART_HWMOD_NAME_LEN];
 268
 269                 snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN,
 270                          "uart%d", num_uarts + 1);
 271                 oh = omap_hwmod_lookup(oh_name);
 272                 if (!oh)
 273                         break;
 274
 275                 uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL);
 276                 if (WARN_ON(!uart))
 277                         return -ENODEV;
 278
 279                 uart->oh = oh;
 280                 uart->num = num_uarts++;
 281                 list_add_tail(&uart->node, &uart_list);
 282                 snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN,
 283                                 "%s%d", OMAP_SERIAL_NAME, uart->num);
 284
 285                 if (cmdline_find_option(uart_name)) {
 286                         console_uart_id = uart->num;
 287
 288                         if (console_loglevel >= 10) {
 289                                 uart_debug = true;
 290                                 pr_info("%s used as console in debug mode"
 291                                                 " uart%d clocks will not be"
 292                                                 " gated", uart_name, uart->num);
 293                         }
 294
 295                         if (cmdline_find_option("no_console_suspend"))
 296                                 no_console_suspend = true;
 297
 298                         /*
 299                          * omap-uart can be used for earlyprintk logs
 300                          * So if omap-uart is used as console then prevent
 301                          * uart reset and idle to get logs from omap-uart
 302                          * until uart console driver is available to take
 303                          * care for console messages.
 304                          * Idling or resetting omap-uart while printing logs
 305                          * early boot logs can stall the boot-up.
 306                          */
 307                         oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET;
 308                 }
 309         } while (1);
 310
 311         return 0;
 312 }
 313 core_initcall(omap_serial_early_init);
 314
 315 /**
 316  * omap_serial_init_port() - initialize single serial port
 317  * @bdata: port specific board data pointer
 318  * @info: platform specific data pointer
 319  *
 320  * This function initialies serial driver for given port only.
 321  * Platforms can call this function instead of omap_serial_init()
 322  * if they don't plan to use all available UARTs as serial ports.
 323  *
 324  * Don't mix calls to omap_serial_init_port() and omap_serial_init(),
 325  * use only one of the two.
 326  */
 327 void __init omap_serial_init_port(struct omap_board_data *bdata,
 328                         struct omap_uart_port_info *info)
 329 {
 330         struct omap_uart_state *uart;
 331         struct omap_hwmod *oh;
 332         struct platform_device *pdev;
 333         void *pdata = NULL;
 334         u32 pdata_size = 0;
 335         char *name;
 336         struct omap_uart_port_info omap_up;
 337
 338         if (WARN_ON(!bdata))
 339                 return;
 340         if (WARN_ON(bdata->id < 0))
 341                 return;
 342         if (WARN_ON(bdata->id >= num_uarts))
 343                 return;
 344
 345         list_for_each_entry(uart, &uart_list, node)
 346                 if (bdata->id == uart->num)
 347                         break;
 348         if (!info)
 349                 info = omap_serial_default_info;
 350
 351         oh = uart->oh;
 352         name = DRIVER_NAME;
 353
 354         omap_up.dma_enabled = info->dma_enabled;
 355         omap_up.uartclk = OMAP24XX_BASE_BAUD * 16;
 356         omap_up.flags = UPF_BOOT_AUTOCONF;
 357         omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count;
 358         omap_up.set_forceidle = omap_uart_set_smartidle;
 359         omap_up.set_noidle = omap_uart_set_noidle;
 360         omap_up.enable_wakeup = omap_uart_enable_wakeup;
 361         omap_up.dma_rx_buf_size = info->dma_rx_buf_size;
 362         omap_up.dma_rx_timeout = info->dma_rx_timeout;
 363         omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate;
 364         omap_up.autosuspend_timeout = info->autosuspend_timeout;
 365
 366         /* Enable the MDR1 Errata i202 for OMAP2430/3xxx/44xx */
 367         if (!cpu_is_omap2420() && !cpu_is_ti816x())
 368                 omap_up.errata |= UART_ERRATA_i202_MDR1_ACCESS;
 369
 370         /* Enable DMA Mode Force Idle Errata i291 for omap34xx/3630 */
 371         if (cpu_is_omap34xx() || cpu_is_omap3630())
 372                 omap_up.errata |= UART_ERRATA_i291_DMA_FORCEIDLE;
 373
 374         pdata = &omap_up;
 375         pdata_size = sizeof(struct omap_uart_port_info);
 376
 377         if (WARN_ON(!oh))
 378                 return;
 379
 380         pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size,
 381                                  NULL, 0, false);
 382         WARN(IS_ERR(pdev), "Could not build omap_device for %s: %s.\n",
 383              name, oh->name);
 384
 385         if ((console_uart_id == bdata->id) && no_console_suspend)
 386                 omap_device_disable_idle_on_suspend(pdev);
 387
 388         oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt);
 389
 390         uart->pdev = pdev;
 391
 392         oh->dev_attr = uart;
 393
 394         if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
 395                         && !uart_debug)
 396                 device_init_wakeup(&pdev->dev, true);
 397 }
 398
 399 /**
 400  * omap_serial_board_init() - initialize all supported serial ports
 401  * @info: platform specific data pointer
 402  *
 403  * Initializes all available UARTs as serial ports. Platforms
 404  * can call this function when they want to have default behaviour
 405  * for serial ports (e.g initialize them all as serial ports).
 406  */
 407 void __init omap_serial_board_init(struct omap_uart_port_info *info)
 408 {
 409         struct omap_uart_state *uart;
 410         struct omap_board_data bdata;
 411
 412         list_for_each_entry(uart, &uart_list, node) {
 413                 bdata.id = uart->num;
 414                 bdata.flags = 0;
 415                 bdata.pads = NULL;
 416                 bdata.pads_cnt = 0;
 417
 418                 if (cpu_is_omap44xx() || cpu_is_omap34xx())
 419                         omap_serial_fill_default_pads(&bdata);
 420
 421                 if (!info)
 422                         omap_serial_init_port(&bdata, NULL);
 423                 else
 424                         omap_serial_init_port(&bdata, &info[uart->num]);
 425         }
 426 }
 427
 428 /**
 429  * omap_serial_init() - initialize all supported serial ports
 430  *
 431  * Initializes all available UARTs.
 432  * Platforms can call this function when they want to have default behaviour
 433  * for serial ports (e.g initialize them all as serial ports).
 434  */
 435 void __init omap_serial_init(void)
 436 {
 437         omap_serial_board_init(NULL);
 438 }