yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 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 | u8 idlemode; |
| 112 | |
| 113 | if (od->hwmods[0]->class->sysc->idlemodes & SIDLE_SMART_WKUP) |
| 114 | idlemode = HWMOD_IDLEMODE_SMART_WKUP; |
| 115 | else |
| 116 | idlemode = HWMOD_IDLEMODE_SMART; |
| 117 | |
| 118 | omap_hwmod_set_slave_idlemode(od->hwmods[0], idlemode); |
| 119 | } |
| 120 | |
| 121 | #else |
| 122 | static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable) |
| 123 | {} |
| 124 | static void omap_uart_set_noidle(struct platform_device *pdev) {} |
| 125 | static void omap_uart_set_smartidle(struct platform_device *pdev) {} |
| 126 | #endif /* CONFIG_PM */ |
| 127 | |
| 128 | #ifdef CONFIG_OMAP_MUX |
| 129 | static void omap_serial_fill_default_pads(struct omap_board_data *bdata) |
| 130 | { |
| 131 | } |
| 132 | #else |
| 133 | static void omap_serial_fill_default_pads(struct omap_board_data *bdata) {} |
| 134 | #endif |
| 135 | |
| 136 | char *cmdline_find_option(char *str) |
| 137 | { |
| 138 | extern char *saved_command_line; |
| 139 | |
| 140 | return strstr(saved_command_line, str); |
| 141 | } |
| 142 | |
| 143 | static int __init omap_serial_early_init(void) |
| 144 | { |
| 145 | do { |
| 146 | char oh_name[MAX_UART_HWMOD_NAME_LEN]; |
| 147 | struct omap_hwmod *oh; |
| 148 | struct omap_uart_state *uart; |
| 149 | char uart_name[MAX_UART_HWMOD_NAME_LEN]; |
| 150 | |
| 151 | snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN, |
| 152 | "uart%d", num_uarts + 1); |
| 153 | oh = omap_hwmod_lookup(oh_name); |
| 154 | if (!oh) |
| 155 | break; |
| 156 | |
| 157 | uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL); |
| 158 | if (WARN_ON(!uart)) |
| 159 | return -ENODEV; |
| 160 | |
| 161 | uart->oh = oh; |
| 162 | uart->num = num_uarts++; |
| 163 | list_add_tail(&uart->node, &uart_list); |
| 164 | snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN, |
| 165 | "%s%d", OMAP_SERIAL_NAME, uart->num); |
| 166 | |
| 167 | if (cmdline_find_option(uart_name)) { |
| 168 | console_uart_id = uart->num; |
| 169 | |
| 170 | if (console_loglevel >= 10) { |
| 171 | uart_debug = true; |
| 172 | pr_info("%s used as console in debug mode" |
| 173 | " uart%d clocks will not be" |
| 174 | " gated", uart_name, uart->num); |
| 175 | } |
| 176 | |
| 177 | if (cmdline_find_option("no_console_suspend")) |
| 178 | no_console_suspend = true; |
| 179 | |
| 180 | /* |
| 181 | * omap-uart can be used for earlyprintk logs |
| 182 | * So if omap-uart is used as console then prevent |
| 183 | * uart reset and idle to get logs from omap-uart |
| 184 | * until uart console driver is available to take |
| 185 | * care for console messages. |
| 186 | * Idling or resetting omap-uart while printing logs |
| 187 | * early boot logs can stall the boot-up. |
| 188 | */ |
| 189 | oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET; |
| 190 | } |
| 191 | } while (1); |
| 192 | |
| 193 | return 0; |
| 194 | } |
| 195 | core_initcall(omap_serial_early_init); |
| 196 | |
| 197 | /** |
| 198 | * omap_serial_init_port() - initialize single serial port |
| 199 | * @bdata: port specific board data pointer |
| 200 | * @info: platform specific data pointer |
| 201 | * |
| 202 | * This function initialies serial driver for given port only. |
| 203 | * Platforms can call this function instead of omap_serial_init() |
| 204 | * if they don't plan to use all available UARTs as serial ports. |
| 205 | * |
| 206 | * Don't mix calls to omap_serial_init_port() and omap_serial_init(), |
| 207 | * use only one of the two. |
| 208 | */ |
| 209 | void __init omap_serial_init_port(struct omap_board_data *bdata, |
| 210 | struct omap_uart_port_info *info) |
| 211 | { |
| 212 | struct omap_uart_state *uart; |
| 213 | struct omap_hwmod *oh; |
| 214 | struct platform_device *pdev; |
| 215 | void *pdata = NULL; |
| 216 | u32 pdata_size = 0; |
| 217 | char *name; |
| 218 | struct omap_uart_port_info omap_up; |
| 219 | |
| 220 | if (WARN_ON(!bdata)) |
| 221 | return; |
| 222 | if (WARN_ON(bdata->id < 0)) |
| 223 | return; |
| 224 | if (WARN_ON(bdata->id >= num_uarts)) |
| 225 | return; |
| 226 | |
| 227 | list_for_each_entry(uart, &uart_list, node) |
| 228 | if (bdata->id == uart->num) |
| 229 | break; |
| 230 | if (!info) |
| 231 | info = omap_serial_default_info; |
| 232 | |
| 233 | oh = uart->oh; |
| 234 | name = DRIVER_NAME; |
| 235 | |
| 236 | omap_up.dma_enabled = info->dma_enabled; |
| 237 | omap_up.uartclk = OMAP24XX_BASE_BAUD * 16; |
| 238 | omap_up.flags = UPF_BOOT_AUTOCONF; |
| 239 | omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count; |
| 240 | omap_up.set_forceidle = omap_uart_set_smartidle; |
| 241 | omap_up.set_noidle = omap_uart_set_noidle; |
| 242 | omap_up.enable_wakeup = omap_uart_enable_wakeup; |
| 243 | omap_up.dma_rx_buf_size = info->dma_rx_buf_size; |
| 244 | omap_up.dma_rx_timeout = info->dma_rx_timeout; |
| 245 | omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate; |
| 246 | omap_up.autosuspend_timeout = info->autosuspend_timeout; |
| 247 | |
| 248 | /* Enable the MDR1 Errata i202 for OMAP2430/3xxx/44xx */ |
| 249 | if (!cpu_is_omap2420() && !cpu_is_ti816x()) |
| 250 | omap_up.errata |= UART_ERRATA_i202_MDR1_ACCESS; |
| 251 | |
| 252 | /* Enable DMA Mode Force Idle Errata i291 for omap34xx/3630 */ |
| 253 | if (cpu_is_omap34xx() || cpu_is_omap3630()) |
| 254 | omap_up.errata |= UART_ERRATA_i291_DMA_FORCEIDLE; |
| 255 | |
| 256 | pdata = &omap_up; |
| 257 | pdata_size = sizeof(struct omap_uart_port_info); |
| 258 | |
| 259 | if (WARN_ON(!oh)) |
| 260 | return; |
| 261 | |
| 262 | pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size, |
| 263 | NULL, 0, false); |
| 264 | WARN(IS_ERR(pdev), "Could not build omap_device for %s: %s.\n", |
| 265 | name, oh->name); |
| 266 | |
| 267 | if ((console_uart_id == bdata->id) && no_console_suspend) |
| 268 | omap_device_disable_idle_on_suspend(pdev); |
| 269 | |
| 270 | oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt); |
| 271 | |
| 272 | oh->dev_attr = uart; |
| 273 | |
| 274 | if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads) |
| 275 | && !uart_debug) |
| 276 | device_init_wakeup(&pdev->dev, true); |
| 277 | } |
| 278 | |
| 279 | /** |
| 280 | * omap_serial_board_init() - initialize all supported serial ports |
| 281 | * @info: platform specific data pointer |
| 282 | * |
| 283 | * Initializes all available UARTs as serial ports. Platforms |
| 284 | * can call this function when they want to have default behaviour |
| 285 | * for serial ports (e.g initialize them all as serial ports). |
| 286 | */ |
| 287 | void __init omap_serial_board_init(struct omap_uart_port_info *info) |
| 288 | { |
| 289 | struct omap_uart_state *uart; |
| 290 | struct omap_board_data bdata; |
| 291 | |
| 292 | list_for_each_entry(uart, &uart_list, node) { |
| 293 | bdata.id = uart->num; |
| 294 | bdata.flags = 0; |
| 295 | bdata.pads = NULL; |
| 296 | bdata.pads_cnt = 0; |
| 297 | |
| 298 | if (cpu_is_omap44xx() || cpu_is_omap34xx()) |
| 299 | omap_serial_fill_default_pads(&bdata); |
| 300 | |
| 301 | if (!info) |
| 302 | omap_serial_init_port(&bdata, NULL); |
| 303 | else |
| 304 | omap_serial_init_port(&bdata, &info[uart->num]); |
| 305 | } |
| 306 | } |
| 307 | |
| 308 | /** |
| 309 | * omap_serial_init() - initialize all supported serial ports |
| 310 | * |
| 311 | * Initializes all available UARTs. |
| 312 | * Platforms can call this function when they want to have default behaviour |
| 313 | * for serial ports (e.g initialize them all as serial ports). |
| 314 | */ |
| 315 | void __init omap_serial_init(void) |
| 316 | { |
| 317 | omap_serial_board_init(NULL); |
| 318 | } |