u-boot/arch/arm/mach-at91/clock.c
Stefan Roese 256c2ff0cc arm: at91: Enable watchdog support
This patch enables and starts the watchdog on the AT91 platform if
configured. The WD timeout value is read in the AT91 WD device driver
from the DT, using the "timeout-sec" DT property. If not provided in
the DT, the default value of 2 seconds is used.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Andreas Bießmann <andreas@biessmann.org>
Cc: Eugen Hristev <eugen.hristev@microchip.com>
2019-04-09 09:28:50 +03:00

168 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2015 Atmel Corporation
* Wenyou Yang <wenyou.yang@atmel.com>
*/
#include <common.h>
#include <dm.h>
#include <wdt.h>
#include <asm/io.h>
#include <asm/arch/hardware.h>
#include <asm/arch/at91_pmc.h>
#include <asm/arch/at91_wdt.h>
#define EN_UPLL_TIMEOUT 500
static struct udevice *watchdog_dev __attribute__((section(".data"))) = NULL;
void at91_periph_clk_enable(int id)
{
struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
#ifdef CPU_HAS_PCR
u32 regval;
u32 div_value;
if (id > AT91_PMC_PCR_PID_MASK)
return;
writel(id, &pmc->pcr);
div_value = readl(&pmc->pcr) & AT91_PMC_PCR_DIV;
regval = AT91_PMC_PCR_EN | AT91_PMC_PCR_CMD_WRITE | id | div_value;
writel(regval, &pmc->pcr);
#else
writel(0x01 << id, &pmc->pcer);
#endif
}
void at91_periph_clk_disable(int id)
{
struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
#ifdef CPU_HAS_PCR
u32 regval;
if (id > AT91_PMC_PCR_PID_MASK)
return;
regval = AT91_PMC_PCR_CMD_WRITE | id;
writel(regval, &pmc->pcr);
#else
writel(0x01 << id, &pmc->pcdr);
#endif
}
void at91_system_clk_enable(int sys_clk)
{
struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
writel(sys_clk, &pmc->scer);
}
void at91_system_clk_disable(int sys_clk)
{
struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
writel(sys_clk, &pmc->scdr);
}
int at91_upll_clk_enable(void)
{
struct at91_pmc *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
ulong start_time, tmp_time;
if ((readl(&pmc->uckr) & AT91_PMC_UPLLEN) == AT91_PMC_UPLLEN)
return 0;
start_time = get_timer(0);
writel(AT91_PMC_UPLLEN | AT91_PMC_BIASEN, &pmc->uckr);
while ((readl(&pmc->sr) & AT91_PMC_LOCKU) != AT91_PMC_LOCKU) {
tmp_time = get_timer(0);
if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
printf("ERROR: failed to enable UPLL\n");
return -1;
}
}
return 0;
}
int at91_upll_clk_disable(void)
{
struct at91_pmc *pmc = (at91_pmc_t *)ATMEL_BASE_PMC;
ulong start_time, tmp_time;
start_time = get_timer(0);
writel(readl(&pmc->uckr) & ~AT91_PMC_UPLLEN, &pmc->uckr);
while ((readl(&pmc->sr) & AT91_PMC_LOCKU) == AT91_PMC_LOCKU) {
tmp_time = get_timer(0);
if ((tmp_time - start_time) > EN_UPLL_TIMEOUT) {
printf("ERROR: failed to stop UPLL\n");
return -1;
}
}
return 0;
}
void at91_usb_clk_init(u32 value)
{
struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
writel(value, &pmc->usb);
}
void at91_pllicpr_init(u32 icpr)
{
struct at91_pmc *pmc = (struct at91_pmc *)ATMEL_BASE_PMC;
writel(icpr, &pmc->pllicpr);
}
/* Called by macro WATCHDOG_RESET */
void watchdog_reset(void)
{
static ulong next_reset;
ulong now;
if (!watchdog_dev)
return;
now = get_timer(0);
/* Do not reset the watchdog too often */
if (now > next_reset) {
next_reset = now + 1000; /* reset every 1000ms */
wdt_reset(watchdog_dev);
}
}
int arch_early_init_r(void)
{
struct at91_wdt_priv *priv;
/* Init watchdog */
if (uclass_get_device_by_seq(UCLASS_WDT, 0, &watchdog_dev)) {
debug("Watchdog: Not found by seq!\n");
if (uclass_get_device(UCLASS_WDT, 0, &watchdog_dev)) {
puts("Watchdog: Not found!\n");
return 0;
}
}
priv = dev_get_priv(watchdog_dev);
if (!priv) {
printf("Watchdog: priv not available!\n");
return 0;
}
wdt_start(watchdog_dev, priv->timeout * 1000, 0);
printf("Watchdog: Started\n");
return 0;
}