| /* |
| * Copyright (c) 2008 Travis Geiselbrecht |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining |
| * a copy of this software and associated documentation files |
| * (the "Software"), to deal in the Software without restriction, |
| * including without limitation the rights to use, copy, modify, merge, |
| * publish, distribute, sublicense, and/or sell copies of the Software, |
| * and to permit persons to whom the Software is furnished to do so, |
| * subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be |
| * included in all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. |
| * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY |
| * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, |
| * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE |
| * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| */ |
| #include <sys/types.h> |
| #include <err.h> |
| #include <reg.h> |
| #include <debug.h> |
| #include <kernel/thread.h> |
| #include <platform.h> |
| #include <platform/interrupts.h> |
| #include <platform/timer.h> |
| #include <platform/omap3.h> |
| #include "platform_p.h" |
| |
| static time_t tick_interval; |
| static platform_timer_callback t_callback; |
| static void *callback_arg; |
| |
| /* timer 2 */ |
| static const ulong timer_base = OMAP34XX_GPT2; |
| |
| #define TIMER_TICK_RATE 32768 |
| |
| #define TIMER_REG(reg) *REG32(timer_base + (reg)) |
| |
| status_t platform_set_periodic_timer(platform_timer_callback callback, void *arg, time_t interval) |
| { |
| enter_critical_section(); |
| |
| t_callback = callback; |
| callback_arg = arg; |
| tick_interval = interval; |
| uint32_t ticks_per_interval = (uint64_t)interval * TIMER_TICK_RATE / 1000; // interval is in ms |
| |
| TIMER_REG(TCLR) = 0; // stop the timer |
| TIMER_REG(TLDR) = -ticks_per_interval; |
| TIMER_REG(TTGR) = 1; |
| TIMER_REG(TIER) = 0x2; |
| TIMER_REG(TCLR) = 0x3; // autoreload, start |
| |
| unmask_interrupt(GPT2_IRQ); |
| |
| exit_critical_section(); |
| |
| return NO_ERROR; |
| } |
| |
| time_t current_time(void) |
| { |
| uint32_t delta_ticks; |
| uint32_t delta_ticks2; |
| |
| retry: |
| delta_ticks = *REG32(TIMER32K_CR); |
| delta_ticks2 = *REG32(TIMER32K_CR); |
| if (delta_ticks2 != delta_ticks) |
| goto retry; |
| |
| uint64_t longtime = delta_ticks * 1000ULL / 32768ULL; |
| |
| return (time_t)longtime; |
| } |
| |
| bigtime_t current_time_hires(void) |
| { |
| uint32_t delta_ticks; |
| uint32_t delta_ticks2; |
| |
| retry: |
| delta_ticks = *REG32(TIMER32K_CR); |
| delta_ticks2 = *REG32(TIMER32K_CR); |
| if (delta_ticks2 != delta_ticks) |
| goto retry; |
| |
| uint64_t longtime = delta_ticks * 1000000ULL / 32768ULL; |
| |
| return (bigtime_t)longtime; |
| } |
| static enum handler_return os_timer_tick(void *arg) |
| { |
| TIMER_REG(TISR) = TIMER_REG(TISR); |
| |
| return t_callback(callback_arg, current_time()); |
| } |
| |
| void platform_init_timer(void) |
| { |
| /* GPT2 */ |
| RMWREG32(CM_CLKSEL_PER, 0, 1, 1); |
| RMWREG32(CM_ICLKEN_PER, 3, 1, 1); |
| RMWREG32(CM_FCLKEN_PER, 3, 1, 1); |
| |
| // reset the GP timer |
| TIMER_REG(TIOCP_CFG) = 0x2; |
| while ((TIMER_REG(TISTAT) & 1) == 0) |
| ; |
| |
| // set GPT2-9 clock inputs over to 32k |
| *REG32(CM_CLKSEL_PER) = 0; |
| |
| // disable ints |
| TIMER_REG(TIER) = 0; |
| TIMER_REG(TISR) = 0x7; // clear any pending bits |
| |
| // XXX make sure 32K timer is running |
| |
| register_int_handler(GPT2_IRQ, &os_timer_tick, NULL); |
| } |
| |
| void platform_halt_timers(void) |
| { |
| TIMER_REG(TCLR) = 0; |
| } |
| |