linux/arch/arm/mach-omap2/serial.c
Govindraj.R 2fd149645e ARM: OMAP2+: UART: Remove omap_uart_can_sleep and add pm_qos
Omap_uart_can_sleep function blocks system wide low power state until
uart is active remove this func and add qos requests to prevent
MPU from transitioning.

Keep qos request to default value which will allow MPU to transition
and while uart baud rate is available calculate the latency value
from the baudrate and use the same to hold constraint while uart clocks
are enabled, and if uart is auto-idled the constraint is updated with
default constraint value allowing MPU to transition.

Qos requests are blocking notifier calls so put these requests to
work queue, also the driver uses irq_safe version of runtime API's
and callbacks can be called in interrupt disabled context.
So to avoid warn on slow path warning while using qos update
API's from runtime callbacks use the qos_work_queue.

During bootup the runtime_resume call backs might not be called and runtime
callback gets called only after uart is idled by setting the autosuspend
timeout. So qos_request from runtime resume callback might not activated during
boot if uart baudrate is calculated during bootup for console uart, so schedule
the qos_work queue once we calc_latency while configuring the uart port.

Flush and complete any pending qos jobs in work queue while suspending.

Signed-off-by: Govindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: Kevin Hilman <khilman@ti.com>
2011-12-14 16:05:26 -08:00

433 lines
11 KiB
C

/*
* arch/arm/mach-omap2/serial.c
*
* OMAP2 serial support.
*
* Copyright (C) 2005-2008 Nokia Corporation
* Author: Paul Mundt <paul.mundt@nokia.com>
*
* Major rework for PM support by Kevin Hilman
*
* Based off of arch/arm/mach-omap/omap1/serial.c
*
* Copyright (C) 2009 Texas Instruments
* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/console.h>
#include <plat/omap-serial.h>
#include "common.h"
#include <plat/board.h>
#include <plat/dma.h>
#include <plat/omap_hwmod.h>
#include <plat/omap_device.h>
#include <plat/omap-pm.h>
#include "prm2xxx_3xxx.h"
#include "pm.h"
#include "cm2xxx_3xxx.h"
#include "prm-regbits-34xx.h"
#include "control.h"
#include "mux.h"
/*
* NOTE: By default the serial auto_suspend timeout is disabled as it causes
* lost characters over the serial ports. This means that the UART clocks will
* stay on until power/autosuspend_delay is set for the uart from sysfs.
* This also causes that any deeper omap sleep states are blocked.
*/
#define DEFAULT_AUTOSUSPEND_DELAY -1
#define MAX_UART_HWMOD_NAME_LEN 16
struct omap_uart_state {
int num;
int can_sleep;
struct list_head node;
struct omap_hwmod *oh;
struct platform_device *pdev;
};
static LIST_HEAD(uart_list);
static u8 num_uarts;
static u8 console_uart_id = -1;
static u8 no_console_suspend;
static u8 uart_debug;
#define DEFAULT_RXDMA_POLLRATE 1 /* RX DMA polling rate (us) */
#define DEFAULT_RXDMA_BUFSIZE 4096 /* RX DMA buffer size */
#define DEFAULT_RXDMA_TIMEOUT (3 * HZ)/* RX DMA timeout (jiffies) */
static struct omap_uart_port_info omap_serial_default_info[] __initdata = {
{
.dma_enabled = false,
.dma_rx_buf_size = DEFAULT_RXDMA_BUFSIZE,
.dma_rx_poll_rate = DEFAULT_RXDMA_POLLRATE,
.dma_rx_timeout = DEFAULT_RXDMA_TIMEOUT,
.autosuspend_timeout = DEFAULT_AUTOSUSPEND_DELAY,
},
};
#ifdef CONFIG_PM
static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
{
struct omap_device *od = to_omap_device(pdev);
if (!od)
return;
if (enable)
omap_hwmod_enable_wakeup(od->hwmods[0]);
else
omap_hwmod_disable_wakeup(od->hwmods[0]);
}
/*
* Errata i291: [UART]:Cannot Acknowledge Idle Requests
* in Smartidle Mode When Configured for DMA Operations.
* WA: configure uart in force idle mode.
*/
static void omap_uart_set_noidle(struct platform_device *pdev)
{
struct omap_device *od = to_omap_device(pdev);
omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_NO);
}
static void omap_uart_set_forceidle(struct platform_device *pdev)
{
struct omap_device *od = to_omap_device(pdev);
omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_FORCE);
}
#else
static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
{}
static void omap_uart_set_noidle(struct platform_device *pdev) {}
static void omap_uart_set_forceidle(struct platform_device *pdev) {}
#endif /* CONFIG_PM */
#ifdef CONFIG_OMAP_MUX
static struct omap_device_pad default_uart1_pads[] __initdata = {
{
.name = "uart1_cts.uart1_cts",
.enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
},
{
.name = "uart1_rts.uart1_rts",
.enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
},
{
.name = "uart1_tx.uart1_tx",
.enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
},
{
.name = "uart1_rx.uart1_rx",
.flags = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
.enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
.idle = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
},
};
static struct omap_device_pad default_uart2_pads[] __initdata = {
{
.name = "uart2_cts.uart2_cts",
.enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
},
{
.name = "uart2_rts.uart2_rts",
.enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
},
{
.name = "uart2_tx.uart2_tx",
.enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
},
{
.name = "uart2_rx.uart2_rx",
.flags = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
.enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
.idle = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
},
};
static struct omap_device_pad default_uart3_pads[] __initdata = {
{
.name = "uart3_cts_rctx.uart3_cts_rctx",
.enable = OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
},
{
.name = "uart3_rts_sd.uart3_rts_sd",
.enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
},
{
.name = "uart3_tx_irtx.uart3_tx_irtx",
.enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
},
{
.name = "uart3_rx_irrx.uart3_rx_irrx",
.flags = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
.enable = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
.idle = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
},
};
static struct omap_device_pad default_omap36xx_uart4_pads[] __initdata = {
{
.name = "gpmc_wait2.uart4_tx",
.enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
},
{
.name = "gpmc_wait3.uart4_rx",
.flags = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
.enable = OMAP_PIN_INPUT | OMAP_MUX_MODE2,
.idle = OMAP_PIN_INPUT | OMAP_MUX_MODE2,
},
};
static struct omap_device_pad default_omap4_uart4_pads[] __initdata = {
{
.name = "uart4_tx.uart4_tx",
.enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
},
{
.name = "uart4_rx.uart4_rx",
.flags = OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
.enable = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
.idle = OMAP_PIN_INPUT | OMAP_MUX_MODE0,
},
};
static void omap_serial_fill_default_pads(struct omap_board_data *bdata)
{
switch (bdata->id) {
case 0:
bdata->pads = default_uart1_pads;
bdata->pads_cnt = ARRAY_SIZE(default_uart1_pads);
break;
case 1:
bdata->pads = default_uart2_pads;
bdata->pads_cnt = ARRAY_SIZE(default_uart2_pads);
break;
case 2:
bdata->pads = default_uart3_pads;
bdata->pads_cnt = ARRAY_SIZE(default_uart3_pads);
break;
case 3:
if (cpu_is_omap44xx()) {
bdata->pads = default_omap4_uart4_pads;
bdata->pads_cnt =
ARRAY_SIZE(default_omap4_uart4_pads);
} else if (cpu_is_omap3630()) {
bdata->pads = default_omap36xx_uart4_pads;
bdata->pads_cnt =
ARRAY_SIZE(default_omap36xx_uart4_pads);
}
break;
default:
break;
}
}
#else
static void omap_serial_fill_default_pads(struct omap_board_data *bdata) {}
#endif
char *cmdline_find_option(char *str)
{
extern char *saved_command_line;
return strstr(saved_command_line, str);
}
static int __init omap_serial_early_init(void)
{
do {
char oh_name[MAX_UART_HWMOD_NAME_LEN];
struct omap_hwmod *oh;
struct omap_uart_state *uart;
char uart_name[MAX_UART_HWMOD_NAME_LEN];
snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN,
"uart%d", num_uarts + 1);
oh = omap_hwmod_lookup(oh_name);
if (!oh)
break;
uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL);
if (WARN_ON(!uart))
return -ENODEV;
uart->oh = oh;
uart->num = num_uarts++;
list_add_tail(&uart->node, &uart_list);
snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN,
"%s%d", OMAP_SERIAL_NAME, uart->num);
if (cmdline_find_option(uart_name)) {
console_uart_id = uart->num;
if (console_loglevel >= 10) {
uart_debug = true;
pr_info("%s used as console in debug mode"
" uart%d clocks will not be"
" gated", uart_name, uart->num);
}
if (cmdline_find_option("no_console_suspend"))
no_console_suspend = true;
/*
* omap-uart can be used for earlyprintk logs
* So if omap-uart is used as console then prevent
* uart reset and idle to get logs from omap-uart
* until uart console driver is available to take
* care for console messages.
* Idling or resetting omap-uart while printing logs
* early boot logs can stall the boot-up.
*/
oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET;
}
} while (1);
return 0;
}
core_initcall(omap_serial_early_init);
/**
* omap_serial_init_port() - initialize single serial port
* @bdata: port specific board data pointer
* @info: platform specific data pointer
*
* This function initialies serial driver for given port only.
* Platforms can call this function instead of omap_serial_init()
* if they don't plan to use all available UARTs as serial ports.
*
* Don't mix calls to omap_serial_init_port() and omap_serial_init(),
* use only one of the two.
*/
void __init omap_serial_init_port(struct omap_board_data *bdata,
struct omap_uart_port_info *info)
{
struct omap_uart_state *uart;
struct omap_hwmod *oh;
struct platform_device *pdev;
void *pdata = NULL;
u32 pdata_size = 0;
char *name;
struct omap_uart_port_info omap_up;
if (WARN_ON(!bdata))
return;
if (WARN_ON(bdata->id < 0))
return;
if (WARN_ON(bdata->id >= num_uarts))
return;
list_for_each_entry(uart, &uart_list, node)
if (bdata->id == uart->num)
break;
if (!info)
info = omap_serial_default_info;
oh = uart->oh;
name = DRIVER_NAME;
omap_up.dma_enabled = info->dma_enabled;
omap_up.uartclk = OMAP24XX_BASE_BAUD * 16;
omap_up.flags = UPF_BOOT_AUTOCONF;
omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count;
omap_up.set_forceidle = omap_uart_set_forceidle;
omap_up.set_noidle = omap_uart_set_noidle;
omap_up.enable_wakeup = omap_uart_enable_wakeup;
omap_up.dma_rx_buf_size = info->dma_rx_buf_size;
omap_up.dma_rx_timeout = info->dma_rx_timeout;
omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate;
omap_up.autosuspend_timeout = info->autosuspend_timeout;
/* Enable the MDR1 Errata i202 for OMAP2430/3xxx/44xx */
if (!cpu_is_omap2420() && !cpu_is_ti816x())
omap_up.errata |= UART_ERRATA_i202_MDR1_ACCESS;
/* Enable DMA Mode Force Idle Errata i291 for omap34xx/3630 */
if (cpu_is_omap34xx() || cpu_is_omap3630())
omap_up.errata |= UART_ERRATA_i291_DMA_FORCEIDLE;
pdata = &omap_up;
pdata_size = sizeof(struct omap_uart_port_info);
if (WARN_ON(!oh))
return;
pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size,
NULL, 0, false);
WARN(IS_ERR(pdev), "Could not build omap_device for %s: %s.\n",
name, oh->name);
if ((console_uart_id == bdata->id) && no_console_suspend)
omap_device_disable_idle_on_suspend(pdev);
oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt);
uart->pdev = pdev;
oh->dev_attr = uart;
if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
&& !uart_debug)
device_init_wakeup(&pdev->dev, true);
}
/**
* omap_serial_board_init() - initialize all supported serial ports
* @info: platform specific data pointer
*
* Initializes all available UARTs as serial ports. Platforms
* can call this function when they want to have default behaviour
* for serial ports (e.g initialize them all as serial ports).
*/
void __init omap_serial_board_init(struct omap_uart_port_info *info)
{
struct omap_uart_state *uart;
struct omap_board_data bdata;
list_for_each_entry(uart, &uart_list, node) {
bdata.id = uart->num;
bdata.flags = 0;
bdata.pads = NULL;
bdata.pads_cnt = 0;
if (cpu_is_omap44xx() || cpu_is_omap34xx())
omap_serial_fill_default_pads(&bdata);
if (!info)
omap_serial_init_port(&bdata, NULL);
else
omap_serial_init_port(&bdata, &info[uart->num]);
}
}
/**
* omap_serial_init() - initialize all supported serial ports
*
* Initializes all available UARTs.
* Platforms can call this function when they want to have default behaviour
* for serial ports (e.g initialize them all as serial ports).
*/
void __init omap_serial_init(void)
{
omap_serial_board_init(NULL);
}