// 16bit code to handle system clocks.
//
-// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2008-2010 Kevin O'Connor <kevin@koconnor.net>
// Copyright (C) 2002 MandrakeSoft S.A.
//
// This file may be distributed under the terms of the GNU LGPLv3 license.
#include "pic.h" // eoi_pic1
#include "bregs.h" // struct bregs
#include "biosvar.h" // GET_GLOBAL
-#include "usb-hid.h" // usb_check_key
+#include "usb-hid.h" // usb_check_event
// RTC register flags
#define RTC_A_UIP 0x80
* TSC timer
****************************************************************/
-#define PIT_TICK_RATE 1193180 // Underlying HZ of PIT
-#define PIT_TICK_INTERVAL 65536 // Default interval for 18.2Hz timer
-#define TICKS_PER_DAY (u32)((u64)60*60*24*PIT_TICK_RATE / PIT_TICK_INTERVAL)
#define CALIBRATE_COUNT 0x800 // Approx 1.7ms
u32 cpu_khz VAR16VISIBLE;
static void
-calibrate_tsc()
+calibrate_tsc(void)
{
// Setup "timer2"
u8 orig = inb(PORT_PS2_CTRLB);
{
u64 start = rdtscll();
u64 end = start + diff;
- while (!check_time(end))
+ while (!check_tsc(end))
cpu_relax();
}
{
u64 start = rdtscll();
u64 end = start + diff;
- while (!check_time(end))
+ while (!check_tsc(end))
yield();
}
****************************************************************/
static int
-rtc_updating()
+rtc_updating(void)
{
// This function checks to see if the update-in-progress bit
// is set in CMOS Status Register A. If not, it returns 0.
// to 0, and will return 0 if such a transition occurs. A -1
// is returned only after timing out. The maximum period
// that this bit should be set is constrained to (1984+244)
- // useconds, so we wait for 3 msec max.
+ // useconds, but we wait for longer just to be sure.
if ((inb_cmos(CMOS_STATUS_A) & RTC_A_UIP) == 0)
return 0;
- u64 end = calc_future_tsc(3);
- do {
+ u64 end = calc_future_tsc(15);
+ for (;;) {
if ((inb_cmos(CMOS_STATUS_A) & RTC_A_UIP) == 0)
return 0;
- } while (!check_time(end));
-
- // update-in-progress never transitioned to 0
- return -1;
+ if (check_tsc(end))
+ // update-in-progress never transitioned to 0
+ return -1;
+ yield();
+ }
}
static void
-pit_setup()
+pit_setup(void)
{
// timer0: binary count, 16bit count, mode 2
outb(PM_SEL_TIMER0|PM_ACCESS_WORD|PM_MODE2|PM_CNT_BINARY, PORT_PIT_MODE);
}
static void
-init_rtc()
+init_rtc(void)
{
outb_cmos(0x26, CMOS_STATUS_A); // 32,768Khz src, 976.5625us updates
u8 regB = inb_cmos(CMOS_STATUS_B);
}
void
-timer_setup()
+timer_setup(void)
{
dprintf(3, "init timer\n");
calibrate_tsc();
u32 ticks = (hours * 60 + minutes) * 60 + seconds;
ticks = ((u64)ticks * PIT_TICK_RATE) / PIT_TICK_INTERVAL;
SET_BDA(timer_counter, ticks);
- SET_BDA(timer_rollover, 0);
- enable_hwirq(0, entry_08);
- enable_hwirq(8, entry_70);
+ enable_hwirq(0, FUNC16(entry_08));
+ enable_hwirq(8, FUNC16(entry_70));
}
* Standard clock functions
****************************************************************/
+#define TICKS_PER_DAY (u32)((u64)60*60*24*PIT_TICK_RATE / PIT_TICK_INTERVAL)
+
+// Calculate the timer value at 'count' number of full timer ticks in
+// the future.
+u32
+calc_future_timer_ticks(u32 count)
+{
+ return (GET_BDA(timer_counter) + count + 1) % TICKS_PER_DAY;
+}
+
+// Return the timer value that is 'msecs' time in the future.
+u32
+calc_future_timer(u32 msecs)
+{
+ if (!msecs)
+ return GET_BDA(timer_counter);
+ u32 kticks = DIV_ROUND_UP((u64)msecs * PIT_TICK_RATE, PIT_TICK_INTERVAL);
+ u32 ticks = DIV_ROUND_UP(kticks, 1000);
+ return calc_future_timer_ticks(ticks);
+}
+
+// Check if the given timer value has passed.
+int
+check_timer(u32 end)
+{
+ return (((GET_BDA(timer_counter) + TICKS_PER_DAY - end) % TICKS_PER_DAY)
+ < (TICKS_PER_DAY/2));
+}
+
// get current clock count
static void
handle_1a00(struct bregs *regs)
{
+ yield();
u32 ticks = GET_BDA(timer_counter);
regs->cx = ticks >> 16;
regs->dx = ticks;
handle_1a02(struct bregs *regs)
{
if (rtc_updating()) {
- set_fail(regs);
+ set_invalid(regs);
return;
}
{
regs->ah = 0;
if (rtc_updating()) {
- set_fail(regs);
+ set_invalid(regs);
return;
}
regs->cl = inb_cmos(CMOS_RTC_YEAR);
// My assumption: RegB = (RegB & 01111111b)
if (rtc_updating()) {
init_rtc();
- set_fail(regs);
+ set_invalid(regs);
return;
}
outb_cmos(regs->cl, CMOS_RTC_YEAR);
regs->ax = 0;
if (val8 & RTC_B_AIE) {
// Alarm interrupt enabled already
- set_fail(regs);
+ set_invalid(regs);
return;
}
if (rtc_updating()) {
static void
handle_1aXX(struct bregs *regs)
{
- set_fail(regs);
+ set_unimplemented(regs);
}
// INT 1Ah Time-of-day Service Entry Point
// INT 08h System Timer ISR Entry Point
void VISIBLE16
-handle_08()
+handle_08(void)
{
debug_isr(DEBUG_ISR_08);
SET_BDA(timer_counter, counter);
- usb_check_key();
+ usb_check_event();
// chain to user timer tick INT #0x1c
u32 eax=0, flags;
* Periodic timer
****************************************************************/
+void
+useRTC(void)
+{
+ u16 ebda_seg = get_ebda_seg();
+ int count = GET_EBDA2(ebda_seg, RTCusers);
+ SET_EBDA2(ebda_seg, RTCusers, count+1);
+ if (count)
+ return;
+ // Turn on the Periodic Interrupt timer
+ u8 bRegister = inb_cmos(CMOS_STATUS_B);
+ outb_cmos(bRegister | RTC_B_PIE, CMOS_STATUS_B);
+}
+
+void
+releaseRTC(void)
+{
+ u16 ebda_seg = get_ebda_seg();
+ int count = GET_EBDA2(ebda_seg, RTCusers);
+ SET_EBDA2(ebda_seg, RTCusers, count-1);
+ if (count != 1)
+ return;
+ // Clear the Periodic Interrupt.
+ u8 bRegister = inb_cmos(CMOS_STATUS_B);
+ outb_cmos(bRegister & ~RTC_B_PIE, CMOS_STATUS_B);
+}
+
static int
set_usertimer(u32 usecs, u16 seg, u16 offset)
{
SET_BDA(rtc_wait_flag, RWS_WAIT_PENDING); // Set status byte.
SET_BDA(user_wait_complete_flag, SEGOFF(seg, offset));
SET_BDA(user_wait_timeout, usecs);
-
- // Turn on the Periodic Interrupt timer
- u8 bRegister = inb_cmos(CMOS_STATUS_B);
- outb_cmos(bRegister | RTC_B_PIE, CMOS_STATUS_B);
-
+ useRTC();
return 0;
}
static void
-clear_usertimer()
+clear_usertimer(void)
{
+ if (!(GET_BDA(rtc_wait_flag) & RWS_WAIT_PENDING))
+ return;
// Turn off status byte.
SET_BDA(rtc_wait_flag, 0);
- // Clear the Periodic Interrupt.
- u8 bRegister = inb_cmos(CMOS_STATUS_B);
- outb_cmos(bRegister & ~RTC_B_PIE, CMOS_STATUS_B);
+ releaseRTC();
}
#define RET_ECLOCKINUSE 0x83
u32 count = (regs->cx << 16) | regs->dx;
int ret = set_usertimer(count, GET_SEG(SS), (u32)&statusflag);
if (ret) {
- set_code_fail(regs, RET_ECLOCKINUSE);
+ set_code_invalid(regs, RET_ECLOCKINUSE);
return;
}
while (!statusflag)
int ret = set_usertimer((regs->cx << 16) | regs->dx, regs->es, regs->bx);
if (ret)
// Interval already set.
- set_code_fail(regs, RET_EUNSUPPORTED);
+ set_code_invalid(regs, RET_EUNSUPPORTED);
else
set_success(regs);
}
static void
handle_1583XX(struct bregs *regs)
{
- set_code_fail(regs, RET_EUNSUPPORTED);
+ set_code_unimplemented(regs, RET_EUNSUPPORTED);
regs->al--;
}
// int70h: IRQ8 - CMOS RTC
void VISIBLE16
-handle_70()
+handle_70(void)
{
debug_isr(DEBUG_ISR_70);
// Handle Periodic Interrupt.
+ check_preempt();
+
if (!GET_BDA(rtc_wait_flag))
goto done;
projects / seabios.git / blobdiff