2 * arch/arm/mach-omap2/serial.c
4 * OMAP2 serial support.
6 * Copyright (C) 2005-2008 Nokia Corporation
7 * Author: Paul Mundt <paul.mundt@nokia.com>
9 * Major rework for PM support by Kevin Hilman
11 * Based off of arch/arm/mach-omap/omap1/serial.c
13 * Copyright (C) 2009 Texas Instruments
14 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com
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
20 #include <linux/kernel.h>
21 #include <linux/init.h>
22 #include <linux/clk.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>
30 #include <plat/omap-serial.h>
32 #include <plat/board.h>
34 #include <plat/omap_hwmod.h>
35 #include <plat/omap_device.h>
36 #include <plat/omap-pm.h>
38 #include "prm2xxx_3xxx.h"
40 #include "cm2xxx_3xxx.h"
41 #include "prm-regbits-34xx.h"
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.
51 #define DEFAULT_AUTOSUSPEND_DELAY -1
53 #define MAX_UART_HWMOD_NAME_LEN 16
55 struct omap_uart_state {
59 struct list_head node;
60 struct omap_hwmod *oh;
61 struct platform_device *pdev;
64 static LIST_HEAD(uart_list);
66 static u8 console_uart_id = -1;
67 static u8 no_console_suspend;
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) */
74 static struct omap_uart_port_info omap_serial_default_info[] __initdata = {
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,
85 static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
87 struct omap_device *od = to_omap_device(pdev);
93 omap_hwmod_enable_wakeup(od->hwmods[0]);
95 omap_hwmod_disable_wakeup(od->hwmods[0]);
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.
103 static void omap_uart_set_noidle(struct platform_device *pdev)
105 struct omap_device *od = to_omap_device(pdev);
107 omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_NO);
110 static void omap_uart_set_forceidle(struct platform_device *pdev)
112 struct omap_device *od = to_omap_device(pdev);
114 omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_FORCE);
118 static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
120 static void omap_uart_set_noidle(struct platform_device *pdev) {}
121 static void omap_uart_set_forceidle(struct platform_device *pdev) {}
122 #endif /* CONFIG_PM */
124 #ifdef CONFIG_OMAP_MUX
125 static struct omap_device_pad default_uart1_pads[] __initdata = {
127 .name = "uart1_cts.uart1_cts",
128 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
131 .name = "uart1_rts.uart1_rts",
132 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
135 .name = "uart1_tx.uart1_tx",
136 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
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,
146 static struct omap_device_pad default_uart2_pads[] __initdata = {
148 .name = "uart2_cts.uart2_cts",
149 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
152 .name = "uart2_rts.uart2_rts",
153 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
156 .name = "uart2_tx.uart2_tx",
157 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
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,
167 static struct omap_device_pad default_uart3_pads[] __initdata = {
169 .name = "uart3_cts_rctx.uart3_cts_rctx",
170 .enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
173 .name = "uart3_rts_sd.uart3_rts_sd",
174 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
177 .name = "uart3_tx_irtx.uart3_tx_irtx",
178 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
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,
188 static struct omap_device_pad default_omap36xx_uart4_pads[] __initdata = {
190 .name = "gpmc_wait2.uart4_tx",
191 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
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,
201 static struct omap_device_pad default_omap4_uart4_pads[] __initdata = {
203 .name = "uart4_tx.uart4_tx",
204 .enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
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,
214 static void omap_serial_fill_default_pads(struct omap_board_data *bdata)
218 bdata->pads = default_uart1_pads;
219 bdata->pads_cnt = ARRAY_SIZE(default_uart1_pads);
222 bdata->pads = default_uart2_pads;
223 bdata->pads_cnt = ARRAY_SIZE(default_uart2_pads);
226 bdata->pads = default_uart3_pads;
227 bdata->pads_cnt = ARRAY_SIZE(default_uart3_pads);
230 if (cpu_is_omap44xx()) {
231 bdata->pads = default_omap4_uart4_pads;
233 ARRAY_SIZE(default_omap4_uart4_pads);
234 } else if (cpu_is_omap3630()) {
235 bdata->pads = default_omap36xx_uart4_pads;
237 ARRAY_SIZE(default_omap36xx_uart4_pads);
245 static void omap_serial_fill_default_pads(struct omap_board_data *bdata) {}
248 char *cmdline_find_option(char *str)
250 extern char *saved_command_line;
252 return strstr(saved_command_line, str);
255 static int __init omap_serial_early_init(void)
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];
263 snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN,
264 "uart%d", num_uarts + 1);
265 oh = omap_hwmod_lookup(oh_name);
269 uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL);
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);
279 if (cmdline_find_option(uart_name)) {
280 console_uart_id = uart->num;
282 if (console_loglevel >= 10) {
284 pr_info("%s used as console in debug mode"
285 " uart%d clocks will not be"
286 " gated", uart_name, uart->num);
289 if (cmdline_find_option("no_console_suspend"))
290 no_console_suspend = true;
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.
301 oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET;
307 core_initcall(omap_serial_early_init);
310 * omap_serial_init_port() - initialize single serial port
311 * @bdata: port specific board data pointer
312 * @info: platform specific data pointer
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.
318 * Don't mix calls to omap_serial_init_port() and omap_serial_init(),
319 * use only one of the two.
321 void __init omap_serial_init_port(struct omap_board_data *bdata,
322 struct omap_uart_port_info *info)
324 struct omap_uart_state *uart;
325 struct omap_hwmod *oh;
326 struct platform_device *pdev;
330 struct omap_uart_port_info omap_up;
334 if (WARN_ON(bdata->id < 0))
336 if (WARN_ON(bdata->id >= num_uarts))
339 list_for_each_entry(uart, &uart_list, node)
340 if (bdata->id == uart->num)
343 info = omap_serial_default_info;
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_forceidle;
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;
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;
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;
369 pdata_size = sizeof(struct omap_uart_port_info);
374 pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size,
376 WARN(IS_ERR(pdev), "Could not build omap_device for %s: %s.\n",
379 if ((console_uart_id == bdata->id) && no_console_suspend)
380 omap_device_disable_idle_on_suspend(pdev);
382 oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt);
388 if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
390 device_init_wakeup(&pdev->dev, true);
394 * omap_serial_board_init() - initialize all supported serial ports
395 * @info: platform specific data pointer
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).
401 void __init omap_serial_board_init(struct omap_uart_port_info *info)
403 struct omap_uart_state *uart;
404 struct omap_board_data bdata;
406 list_for_each_entry(uart, &uart_list, node) {
407 bdata.id = uart->num;
412 if (cpu_is_omap44xx() || cpu_is_omap34xx())
413 omap_serial_fill_default_pads(&bdata);
416 omap_serial_init_port(&bdata, NULL);
418 omap_serial_init_port(&bdata, &info[uart->num]);
423 * omap_serial_init() - initialize all supported serial ports
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).
429 void __init omap_serial_init(void)
431 omap_serial_board_init(NULL);