157 lines
4.3 KiB
C
Executable File
157 lines
4.3 KiB
C
Executable File
/*
|
|
* Atmel AT91 SAM9 SoCs reset code
|
|
*
|
|
* Copyright (C) 2007 Atmel Corporation.
|
|
* Copyright (C) 2011 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
|
|
* Copyright (C) 2014 Free Electrons
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public
|
|
* License version 2. This program is licensed "as is" without any
|
|
* warranty of any kind, whether express or implied.
|
|
*/
|
|
|
|
#include <linux/io.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/printk.h>
|
|
|
|
#define AT91_SHDW_CR 0x00 /* Shut Down Control Register */
|
|
#define AT91_SHDW_SHDW BIT(0) /* Shut Down command */
|
|
#define AT91_SHDW_KEY (0xa5 << 24) /* KEY Password */
|
|
|
|
#define AT91_SHDW_MR 0x04 /* Shut Down Mode Register */
|
|
#define AT91_SHDW_WKMODE0 GENMASK(2, 0) /* Wake-up 0 Mode Selection */
|
|
#define AT91_SHDW_CPTWK0_MAX 0xf /* Maximum Counter On Wake Up 0 */
|
|
#define AT91_SHDW_CPTWK0 (AT91_SHDW_CPTWK0_MAX << 4) /* Counter On Wake Up 0 */
|
|
#define AT91_SHDW_CPTWK0_(x) ((x) << 4)
|
|
#define AT91_SHDW_RTTWKEN BIT(16) /* Real Time Timer Wake-up Enable */
|
|
#define AT91_SHDW_RTCWKEN BIT(17) /* Real Time Clock Wake-up Enable */
|
|
|
|
#define AT91_SHDW_SR 0x08 /* Shut Down Status Register */
|
|
#define AT91_SHDW_WAKEUP0 BIT(0) /* Wake-up 0 Status */
|
|
#define AT91_SHDW_RTTWK BIT(16) /* Real-time Timer Wake-up */
|
|
#define AT91_SHDW_RTCWK BIT(17) /* Real-time Clock Wake-up [SAM9RL] */
|
|
|
|
enum wakeup_type {
|
|
AT91_SHDW_WKMODE0_NONE = 0,
|
|
AT91_SHDW_WKMODE0_HIGH = 1,
|
|
AT91_SHDW_WKMODE0_LOW = 2,
|
|
AT91_SHDW_WKMODE0_ANYLEVEL = 3,
|
|
};
|
|
|
|
static const char *shdwc_wakeup_modes[] = {
|
|
[AT91_SHDW_WKMODE0_NONE] = "none",
|
|
[AT91_SHDW_WKMODE0_HIGH] = "high",
|
|
[AT91_SHDW_WKMODE0_LOW] = "low",
|
|
[AT91_SHDW_WKMODE0_ANYLEVEL] = "any",
|
|
};
|
|
|
|
static void __iomem *at91_shdwc_base;
|
|
|
|
static void __init at91_wakeup_status(void)
|
|
{
|
|
u32 reg = readl(at91_shdwc_base + AT91_SHDW_SR);
|
|
char *reason = "unknown";
|
|
|
|
/* Simple power-on, just bail out */
|
|
if (!reg)
|
|
return;
|
|
|
|
if (reg & AT91_SHDW_RTTWK)
|
|
reason = "RTT";
|
|
else if (reg & AT91_SHDW_RTCWK)
|
|
reason = "RTC";
|
|
|
|
pr_info("AT91: Wake-Up source: %s\n", reason);
|
|
}
|
|
|
|
static void at91_poweroff(void)
|
|
{
|
|
writel(AT91_SHDW_KEY | AT91_SHDW_SHDW, at91_shdwc_base + AT91_SHDW_CR);
|
|
}
|
|
|
|
const enum wakeup_type at91_poweroff_get_wakeup_mode(struct device_node *np)
|
|
{
|
|
const char *pm;
|
|
int err, i;
|
|
|
|
err = of_property_read_string(np, "atmel,wakeup-mode", &pm);
|
|
if (err < 0)
|
|
return AT91_SHDW_WKMODE0_ANYLEVEL;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(shdwc_wakeup_modes); i++)
|
|
if (!strcasecmp(pm, shdwc_wakeup_modes[i]))
|
|
return i;
|
|
|
|
return -ENODEV;
|
|
}
|
|
|
|
static void at91_poweroff_dt_set_wakeup_mode(struct platform_device *pdev)
|
|
{
|
|
struct device_node *np = pdev->dev.of_node;
|
|
enum wakeup_type wakeup_mode;
|
|
u32 mode = 0, tmp;
|
|
|
|
wakeup_mode = at91_poweroff_get_wakeup_mode(np);
|
|
if (wakeup_mode < 0) {
|
|
dev_warn(&pdev->dev, "shdwc unknown wakeup mode\n");
|
|
return;
|
|
}
|
|
|
|
if (!of_property_read_u32(np, "atmel,wakeup-counter", &tmp)) {
|
|
if (tmp > AT91_SHDW_CPTWK0_MAX) {
|
|
dev_warn(&pdev->dev,
|
|
"shdwc wakeup counter 0x%x > 0x%x reduce it to 0x%x\n",
|
|
tmp, AT91_SHDW_CPTWK0_MAX, AT91_SHDW_CPTWK0_MAX);
|
|
tmp = AT91_SHDW_CPTWK0_MAX;
|
|
}
|
|
mode |= AT91_SHDW_CPTWK0_(tmp);
|
|
}
|
|
|
|
if (of_property_read_bool(np, "atmel,wakeup-rtc-timer"))
|
|
mode |= AT91_SHDW_RTCWKEN;
|
|
|
|
if (of_property_read_bool(np, "atmel,wakeup-rtt-timer"))
|
|
mode |= AT91_SHDW_RTTWKEN;
|
|
|
|
writel(wakeup_mode | mode, at91_shdwc_base + AT91_SHDW_MR);
|
|
}
|
|
|
|
static int at91_poweroff_probe(struct platform_device *pdev)
|
|
{
|
|
struct resource *res;
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
at91_shdwc_base = devm_ioremap_resource(&pdev->dev, res);
|
|
if (IS_ERR(at91_shdwc_base)) {
|
|
dev_err(&pdev->dev, "Could not map reset controller address\n");
|
|
return PTR_ERR(at91_shdwc_base);
|
|
}
|
|
|
|
at91_wakeup_status();
|
|
|
|
if (pdev->dev.of_node)
|
|
at91_poweroff_dt_set_wakeup_mode(pdev);
|
|
|
|
pm_power_off = at91_poweroff;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct of_device_id at91_poweroff_of_match[] = {
|
|
{ .compatible = "atmel,at91sam9260-shdwc", },
|
|
{ .compatible = "atmel,at91sam9rl-shdwc", },
|
|
{ .compatible = "atmel,at91sam9x5-shdwc", },
|
|
{ /*sentinel*/ }
|
|
};
|
|
|
|
static struct platform_driver at91_poweroff_driver = {
|
|
.probe = at91_poweroff_probe,
|
|
.driver = {
|
|
.name = "at91-poweroff",
|
|
.of_match_table = at91_poweroff_of_match,
|
|
},
|
|
};
|
|
module_platform_driver(at91_poweroff_driver);
|