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 {
58 struct list_head node;
59 struct omap_hwmod *oh;
62 static LIST_HEAD(uart_list);
64 static u8 console_uart_id = -1;
65 static u8 no_console_suspend;
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) */
72 static struct omap_uart_port_info omap_serial_default_info[] __initdata = {
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,
83 static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
85 struct omap_device *od = to_omap_device(pdev);
91 omap_hwmod_enable_wakeup(od->hwmods[0]);
93 omap_hwmod_disable_wakeup(od->hwmods[0]);
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.
101 static void omap_uart_set_noidle(struct platform_device *pdev)
103 struct omap_device *od = to_omap_device(pdev);
105 omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_NO);
108 static void omap_uart_set_smartidle(struct platform_device *pdev)
110 struct omap_device *od = to_omap_device(pdev);
112 omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_SMART);
116 static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
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 */
122 #ifdef CONFIG_OMAP_MUX
123 static void omap_serial_fill_default_pads(struct omap_board_data *bdata)
127 static void omap_serial_fill_default_pads(struct omap_board_data *bdata) {}
130 char *cmdline_find_option(char *str)
132 extern char *saved_command_line;
134 return strstr(saved_command_line, str);
137 static int __init omap_serial_early_init(void)
140 char oh_name[MAX_UART_HWMOD_NAME_LEN];
141 struct omap_hwmod *oh;
142 struct omap_uart_state *uart;
143 char uart_name[MAX_UART_HWMOD_NAME_LEN];
145 snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN,
146 "uart%d", num_uarts + 1);
147 oh = omap_hwmod_lookup(oh_name);
151 uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL);
156 uart->num = num_uarts++;
157 list_add_tail(&uart->node, &uart_list);
158 snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN,
159 "%s%d", OMAP_SERIAL_NAME, uart->num);
161 if (cmdline_find_option(uart_name)) {
162 console_uart_id = uart->num;
164 if (console_loglevel >= 10) {
166 pr_info("%s used as console in debug mode"
167 " uart%d clocks will not be"
168 " gated", uart_name, uart->num);
171 if (cmdline_find_option("no_console_suspend"))
172 no_console_suspend = true;
175 * omap-uart can be used for earlyprintk logs
176 * So if omap-uart is used as console then prevent
177 * uart reset and idle to get logs from omap-uart
178 * until uart console driver is available to take
179 * care for console messages.
180 * Idling or resetting omap-uart while printing logs
181 * early boot logs can stall the boot-up.
183 oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET;
189 core_initcall(omap_serial_early_init);
192 * omap_serial_init_port() - initialize single serial port
193 * @bdata: port specific board data pointer
194 * @info: platform specific data pointer
196 * This function initialies serial driver for given port only.
197 * Platforms can call this function instead of omap_serial_init()
198 * if they don't plan to use all available UARTs as serial ports.
200 * Don't mix calls to omap_serial_init_port() and omap_serial_init(),
201 * use only one of the two.
203 void __init omap_serial_init_port(struct omap_board_data *bdata,
204 struct omap_uart_port_info *info)
206 struct omap_uart_state *uart;
207 struct omap_hwmod *oh;
208 struct platform_device *pdev;
212 struct omap_uart_port_info omap_up;
216 if (WARN_ON(bdata->id < 0))
218 if (WARN_ON(bdata->id >= num_uarts))
221 list_for_each_entry(uart, &uart_list, node)
222 if (bdata->id == uart->num)
225 info = omap_serial_default_info;
230 omap_up.dma_enabled = info->dma_enabled;
231 omap_up.uartclk = OMAP24XX_BASE_BAUD * 16;
232 omap_up.flags = UPF_BOOT_AUTOCONF;
233 omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count;
234 omap_up.set_forceidle = omap_uart_set_smartidle;
235 omap_up.set_noidle = omap_uart_set_noidle;
236 omap_up.enable_wakeup = omap_uart_enable_wakeup;
237 omap_up.dma_rx_buf_size = info->dma_rx_buf_size;
238 omap_up.dma_rx_timeout = info->dma_rx_timeout;
239 omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate;
240 omap_up.autosuspend_timeout = info->autosuspend_timeout;
242 /* Enable the MDR1 Errata i202 for OMAP2430/3xxx/44xx */
243 if (!cpu_is_omap2420() && !cpu_is_ti816x())
244 omap_up.errata |= UART_ERRATA_i202_MDR1_ACCESS;
246 /* Enable DMA Mode Force Idle Errata i291 for omap34xx/3630 */
247 if (cpu_is_omap34xx() || cpu_is_omap3630())
248 omap_up.errata |= UART_ERRATA_i291_DMA_FORCEIDLE;
251 pdata_size = sizeof(struct omap_uart_port_info);
256 pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size,
258 WARN(IS_ERR(pdev), "Could not build omap_device for %s: %s.\n",
261 if ((console_uart_id == bdata->id) && no_console_suspend)
262 omap_device_disable_idle_on_suspend(pdev);
264 oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt);
268 if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
270 device_init_wakeup(&pdev->dev, true);
274 * omap_serial_board_init() - initialize all supported serial ports
275 * @info: platform specific data pointer
277 * Initializes all available UARTs as serial ports. Platforms
278 * can call this function when they want to have default behaviour
279 * for serial ports (e.g initialize them all as serial ports).
281 void __init omap_serial_board_init(struct omap_uart_port_info *info)
283 struct omap_uart_state *uart;
284 struct omap_board_data bdata;
286 list_for_each_entry(uart, &uart_list, node) {
287 bdata.id = uart->num;
292 if (cpu_is_omap44xx() || cpu_is_omap34xx())
293 omap_serial_fill_default_pads(&bdata);
296 omap_serial_init_port(&bdata, NULL);
298 omap_serial_init_port(&bdata, &info[uart->num]);
303 * omap_serial_init() - initialize all supported serial ports
305 * Initializes all available UARTs.
306 * Platforms can call this function when they want to have default behaviour
307 * for serial ports (e.g initialize them all as serial ports).
309 void __init omap_serial_init(void)
311 omap_serial_board_init(NULL);