| /* |
| * Copyright (c) 2012 - 2013 The Linux Foundation. All rights reserved. |
| * Source : APQ8064 LK boot |
| * |
| * Copyright (c) 2011-2012, Code Aurora Forum. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google, Inc. nor the names of its contributors |
| * may be used to endorse or promote products derived from this |
| * software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #include <delay.h> |
| #include <iomap.h> |
| #include <ipq_timer.h> |
| #include <timer.h> |
| |
| #define GPT_FREQ_KHZ 32 |
| #define GPT_FREQ (GPT_FREQ_KHZ * 1000) /* 32 KHz */ |
| |
| /** |
| * timer_init - initialize timer |
| */ |
| void init_timer(void) |
| { |
| writel(0, GPT_ENABLE); |
| writel(GPT_ENABLE_EN, GPT_ENABLE); |
| } |
| |
| /** |
| * udelay - generates micro second delay. |
| * @usec: delay duration in microseconds |
| * |
| * With 32KHz clock, minimum possible delay is 31.25 Micro seconds and |
| * its multiples. In Rumi GPT clock is 32 KHz |
| */ |
| void udelay(unsigned usec) |
| { |
| unsigned val; |
| unsigned now, last; |
| unsigned runcount; |
| |
| usec = (usec + GPT_FREQ_KHZ - 1) / GPT_FREQ_KHZ; |
| last = readl(GPT_COUNT_VAL); |
| runcount = last; |
| val = usec + last; |
| |
| do { |
| now = readl(GPT_COUNT_VAL); |
| if (last > now) |
| runcount += ((GPT_FREQ - last) + now); |
| else |
| runcount += (now - last); |
| last = now; |
| } while (runcount < val); |
| } |
| |
| #if 0 |
| |
| /* |
| * TODO(vbendeb) clean it up later. |
| * Compile out the below code but leave it for now in case it will become |
| * necessary later in order to make the platform fully functional. |
| */ |
| static unsigned long timestamp; |
| static unsigned long lastinc; |
| |
| inline ulong gpt_to_sys_freq(unsigned int gpt) |
| { |
| /* |
| * get_timer() expects the timer increments to be in terms |
| * of CONFIG_SYS_HZ. Convert GPT timer values to CONFIG_SYS_HZ |
| * units. |
| */ |
| return (((ulong)gpt) / (GPT_FREQ / CONFIG_SYS_HZ)); |
| } |
| |
| /** |
| * get_timer_masked - returns current ticks |
| * |
| * Returns the current timer ticks, since boot. |
| */ |
| ulong get_timer_masked(void) |
| { |
| ulong now = gpt_to_sys_freq(readl(GPT_COUNT_VAL)); |
| |
| if (lastinc <= now) { /* normal mode (non roll) */ |
| /* normal mode */ |
| timestamp += now - lastinc; |
| /* move stamp forward with absolute diff ticks */ |
| } else { /* we have overflow of the count down timer */ |
| timestamp += now + (TIMER_LOAD_VAL - lastinc); |
| } |
| |
| lastinc = now; |
| |
| return timestamp; |
| } |
| |
| unsigned long long get_ticks(void) |
| { |
| return readl(GPT_COUNT_VAL); |
| } |
| |
| /* |
| * Return the number of timer ticks per second. |
| */ |
| ulong get_tbclk(void) |
| { |
| return GPT_FREQ; |
| } |
| #endif |