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Diffstat (limited to 'arch/arm/cpu/arm926ejs/armada100/timer.c')
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diff --git a/arch/arm/cpu/arm926ejs/armada100/timer.c b/arch/arm/cpu/arm926ejs/armada100/timer.c
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+/*
+ * (C) Copyright 2010
+ * Marvell Semiconductor <www.marvell.com>
+ * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
+ * Contributor: Mahavir Jain <mjain@marvell.com>
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#include <common.h>
+#include <asm/arch/armada100.h>
+
+/*
+ * Timer registers
+ * Refer Section A.6 in Datasheet
+ */
+struct armd1tmr_registers {
+ u32 clk_ctrl; /* Timer clk control reg */
+ u32 match[9]; /* Timer match registers */
+ u32 count[3]; /* Timer count registers */
+ u32 status[3];
+ u32 ie[3];
+ u32 preload[3]; /* Timer preload value */
+ u32 preload_ctrl[3];
+ u32 wdt_match_en;
+ u32 wdt_match_r;
+ u32 wdt_val;
+ u32 wdt_sts;
+ u32 icr[3];
+ u32 wdt_icr;
+ u32 cer; /* Timer count enable reg */
+ u32 cmr;
+ u32 ilr[3];
+ u32 wcr;
+ u32 wfar;
+ u32 wsar;
+ u32 cvwr;
+};
+
+#define TIMER 0 /* Use TIMER 0 */
+/* Each timer has 3 match registers */
+#define MATCH_CMP(x) ((3 * TIMER) + x)
+#define TIMER_LOAD_VAL 0xffffffff
+#define COUNT_RD_REQ 0x1
+
+DECLARE_GLOBAL_DATA_PTR;
+/* Using gd->tbu from timestamp and gd->tbl for lastdec */
+
+/* For preventing risk of instability in reading counter value,
+ * first set read request to register cvwr and then read same
+ * register after it captures counter value.
+ */
+ulong read_timer(void)
+{
+ struct armd1tmr_registers *armd1timers =
+ (struct armd1tmr_registers *) ARMD1_TIMER_BASE;
+ volatile int loop=100;
+
+ writel(COUNT_RD_REQ, &armd1timers->cvwr);
+ while (loop--);
+ return(readl(&armd1timers->cvwr));
+}
+
+void reset_timer_masked(void)
+{
+ /* reset time */
+ gd->tbl = read_timer();
+ gd->tbu = 0;
+}
+
+ulong get_timer_masked(void)
+{
+ ulong now = read_timer();
+
+ if (now >= gd->tbl) {
+ /* normal mode */
+ gd->tbu += now - gd->tbl;
+ } else {
+ /* we have an overflow ... */
+ gd->tbu += now + TIMER_LOAD_VAL - gd->tbl;
+ }
+ gd->tbl = now;
+
+ return gd->tbu;
+}
+
+void reset_timer(void)
+{
+ reset_timer_masked();
+}
+
+ulong get_timer(ulong base)
+{
+ return ((get_timer_masked() / (CONFIG_SYS_HZ_CLOCK / 1000)) -
+ base);
+}
+
+void set_timer(ulong t)
+{
+ gd->tbu = t;
+}
+
+void __udelay(unsigned long usec)
+{
+ ulong delayticks;
+ ulong endtime;
+
+ delayticks = (usec * (CONFIG_SYS_HZ_CLOCK / 1000000));
+ endtime = get_timer_masked() + delayticks;
+
+ while (get_timer_masked() < endtime);
+}
+
+/*
+ * init the Timer
+ */
+int timer_init(void)
+{
+ struct armd1apb1_registers *apb1clkres =
+ (struct armd1apb1_registers *) ARMD1_APBC1_BASE;
+ struct armd1tmr_registers *armd1timers =
+ (struct armd1tmr_registers *) ARMD1_TIMER_BASE;
+
+ /* Enable Timer clock at 3.25 MHZ */
+ writel(APBC_APBCLK | APBC_FNCLK | APBC_FNCLKSEL(3), &apb1clkres->timers);
+
+ /* load value into timer */
+ writel(0x0, &armd1timers->clk_ctrl);
+ /* Use Timer 0 Match Resiger 0 */
+ writel(TIMER_LOAD_VAL, &armd1timers->match[MATCH_CMP(0)]);
+ /* Preload value is 0 */
+ writel(0x0, &armd1timers->preload[TIMER]);
+ /* Enable match comparator 0 for Timer 0 */
+ writel(0x1, &armd1timers->preload_ctrl[TIMER]);
+
+ /* Enable timer 0 */
+ writel(0x1, &armd1timers->cer);
+ /* init the gd->tbu and gd->tbl value */
+ reset_timer_masked();
+
+ return 0;
+}
+
+#define MPMU_APRR_WDTR (1<<4)
+#define TMR_WFAR 0xbaba /* WDT Register First key */
+#define TMP_WSAR 0xeb10 /* WDT Register Second key */
+
+/*
+ * This function uses internal Watchdog Timer
+ * based reset mechanism.
+ * Steps to write watchdog registers (protected access)
+ * 1. Write key value to TMR_WFAR reg.
+ * 2. Write key value to TMP_WSAR reg.
+ * 3. Perform write operation.
+ */
+void reset_cpu (unsigned long ignored)
+{
+ struct armd1mpmu_registers *mpmu =
+ (struct armd1mpmu_registers *) ARMD1_MPMU_BASE;
+ struct armd1tmr_registers *armd1timers =
+ (struct armd1tmr_registers *) ARMD1_TIMER_BASE;
+ u32 val;
+
+ /* negate hardware reset to the WDT after system reset */
+ val = readl(&mpmu->aprr);
+ val = val | MPMU_APRR_WDTR;
+ writel(val, &mpmu->aprr);
+
+ /* reset/enable WDT clock */
+ writel(APBC_APBCLK | APBC_FNCLK | APBC_RST, &mpmu->wdtpcr);
+ readl(&mpmu->wdtpcr);
+ writel(APBC_APBCLK | APBC_FNCLK, &mpmu->wdtpcr);
+ readl(&mpmu->wdtpcr);
+
+ /* clear previous WDT status */
+ writel(TMR_WFAR, &armd1timers->wfar);
+ writel(TMP_WSAR, &armd1timers->wsar);
+ writel(0, &armd1timers->wdt_sts);
+
+ /* set match counter */
+ writel(TMR_WFAR, &armd1timers->wfar);
+ writel(TMP_WSAR, &armd1timers->wsar);
+ writel(0xf, &armd1timers->wdt_match_r);
+
+ /* enable WDT reset */
+ writel(TMR_WFAR, &armd1timers->wfar);
+ writel(TMP_WSAR, &armd1timers->wsar);
+ writel(0x3, &armd1timers->wdt_match_en);
+
+ while(1);
+}