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authorMarek Vasut <marex@denx.de>2012-07-21 05:02:21 +0000
committerAlbert ARIBAUD <albert.u.boot@aribaud.net>2012-10-18 06:52:02 +0200
commitd731282e7c210bb002cc0a2f3859be4efd3120c7 (patch)
tree71bb7a9566069ccd482fa2792ce1803076658d7e /drivers/watchdog/tnetv107x_wdt.c
parentb9f4bc34ac0ee40f8d6a952036b4cd62b854aa74 (diff)
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dm: wdt: arm: Move tnetv107x into drivers/watchdog/
Signed-off-by: Marek Vasut <marex@denx.de> Cc: Oliver Brown <obrown@adventnetworks.com> Cc: Wolfgang Denk <wd@denx.de> Cc: Albert Aribaud <albert.u.boot@aribaud.net> Cc: U-Boot DM <u-boot-dm@lists.denx.de>
Diffstat (limited to 'drivers/watchdog/tnetv107x_wdt.c')
-rw-r--r--drivers/watchdog/tnetv107x_wdt.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/watchdog/tnetv107x_wdt.c b/drivers/watchdog/tnetv107x_wdt.c
new file mode 100644
index 0000000..18aadb0
--- /dev/null
+++ b/drivers/watchdog/tnetv107x_wdt.c
@@ -0,0 +1,180 @@
+/*
+ * TNETV107X: Watchdog timer implementation (for reset)
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+
+#define MAX_DIV 0xFFFE0001
+
+struct wdt_regs {
+ u32 kick_lock;
+#define KICK_LOCK_1 0x5555
+#define KICK_LOCK_2 0xaaaa
+ u32 kick;
+
+ u32 change_lock;
+#define CHANGE_LOCK_1 0x6666
+#define CHANGE_LOCK_2 0xbbbb
+ u32 change;
+
+ u32 disable_lock;
+#define DISABLE_LOCK_1 0x7777
+#define DISABLE_LOCK_2 0xcccc
+#define DISABLE_LOCK_3 0xdddd
+ u32 disable;
+
+ u32 prescale_lock;
+#define PRESCALE_LOCK_1 0x5a5a
+#define PRESCALE_LOCK_2 0xa5a5
+ u32 prescale;
+};
+
+static struct wdt_regs* regs = (struct wdt_regs *)TNETV107X_WDT0_ARM_BASE;
+
+#define wdt_reg_read(reg) __raw_readl(&regs->reg)
+#define wdt_reg_write(reg, val) __raw_writel((val), &regs->reg)
+
+static int write_prescale_reg(unsigned long prescale_value)
+{
+ wdt_reg_write(prescale_lock, PRESCALE_LOCK_1);
+ if ((wdt_reg_read(prescale_lock) & 0x3) != 0x1)
+ return -1;
+
+ wdt_reg_write(prescale_lock, PRESCALE_LOCK_2);
+ if ((wdt_reg_read(prescale_lock) & 0x3) != 0x3)
+ return -1;
+
+ wdt_reg_write(prescale, prescale_value);
+
+ return 0;
+}
+
+static int write_change_reg(unsigned long initial_timer_value)
+{
+ wdt_reg_write(change_lock, CHANGE_LOCK_1);
+ if ((wdt_reg_read(change_lock) & 0x3) != 0x1)
+ return -1;
+
+ wdt_reg_write(change_lock, CHANGE_LOCK_2);
+ if ((wdt_reg_read(change_lock) & 0x3) != 0x3)
+ return -1;
+
+ wdt_reg_write(change, initial_timer_value);
+
+ return 0;
+}
+
+static int wdt_control(unsigned long disable_value)
+{
+ wdt_reg_write(disable_lock, DISABLE_LOCK_1);
+ if ((wdt_reg_read(disable_lock) & 0x3) != 0x1)
+ return -1;
+
+ wdt_reg_write(disable_lock, DISABLE_LOCK_2);
+ if ((wdt_reg_read(disable_lock) & 0x3) != 0x2)
+ return -1;
+
+ wdt_reg_write(disable_lock, DISABLE_LOCK_3);
+ if ((wdt_reg_read(disable_lock) & 0x3) != 0x3)
+ return -1;
+
+ wdt_reg_write(disable, disable_value);
+ return 0;
+}
+
+static int wdt_set_period(unsigned long msec)
+{
+ unsigned long change_value, count_value;
+ unsigned long prescale_value = 1;
+ unsigned long refclk_khz, maxdiv;
+ int ret;
+
+ refclk_khz = clk_get_rate(TNETV107X_LPSC_WDT_ARM);
+ maxdiv = (MAX_DIV / refclk_khz);
+
+ if ((!msec) || (msec > maxdiv))
+ return -1;
+
+ count_value = refclk_khz * msec;
+ if (count_value > 0xffff) {
+ change_value = count_value / 0xffff + 1;
+ prescale_value = count_value / change_value;
+ } else {
+ change_value = count_value;
+ }
+
+ ret = write_prescale_reg(prescale_value - 1);
+ if (ret)
+ return ret;
+
+ ret = write_change_reg(change_value);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+unsigned long last_wdt = -1;
+
+int wdt_start(unsigned long msecs)
+{
+ int ret;
+ ret = wdt_control(0);
+ if (ret)
+ return ret;
+ ret = wdt_set_period(msecs);
+ if (ret)
+ return ret;
+ ret = wdt_control(1);
+ if (ret)
+ return ret;
+ ret = wdt_kick();
+ last_wdt = msecs;
+ return ret;
+}
+
+int wdt_stop(void)
+{
+ last_wdt = -1;
+ return wdt_control(0);
+}
+
+int wdt_kick(void)
+{
+ wdt_reg_write(kick_lock, KICK_LOCK_1);
+ if ((wdt_reg_read(kick_lock) & 0x3) != 0x1)
+ return -1;
+
+ wdt_reg_write(kick_lock, KICK_LOCK_2);
+ if ((wdt_reg_read(kick_lock) & 0x3) != 0x3)
+ return -1;
+
+ wdt_reg_write(kick, 1);
+ return 0;
+}
+
+void reset_cpu(ulong addr)
+{
+ clk_enable(TNETV107X_LPSC_WDT_ARM);
+ wdt_start(1);
+ wdt_kick();
+}