// 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 GPLv3 license.
+// This file may be distributed under the terms of the GNU LGPLv3 license.
-#include "biosvar.h" // struct bregs
+#include "biosvar.h" // SET_BDA
#include "util.h" // debug_enter
#include "disk.h" // floppy_tick
#include "cmos.h" // inb_cmos
+#include "pic.h" // eoi_pic1
+#include "bregs.h" // struct bregs
+#include "biosvar.h" // GET_GLOBAL
+#include "usb-hid.h" // usb_check_event
+
+// RTC register flags
+#define RTC_A_UIP 0x80
+
+#define RTC_B_SET 0x80
+#define RTC_B_PIE 0x40
+#define RTC_B_AIE 0x20
+#define RTC_B_UIE 0x10
+#define RTC_B_BIN 0x04
+#define RTC_B_24HR 0x02
+#define RTC_B_DSE 0x01
+
+
+// Bits for PORT_PS2_CTRLB
+#define PPCB_T2GATE (1<<0)
+#define PPCB_SPKR (1<<1)
+#define PPCB_T2OUT (1<<5)
+
+// Bits for PORT_PIT_MODE
+#define PM_SEL_TIMER0 (0<<6)
+#define PM_SEL_TIMER1 (1<<6)
+#define PM_SEL_TIMER2 (2<<6)
+#define PM_SEL_READBACK (3<<6)
+#define PM_ACCESS_LATCH (0<<4)
+#define PM_ACCESS_LOBYTE (1<<4)
+#define PM_ACCESS_HIBYTE (2<<4)
+#define PM_ACCESS_WORD (3<<4)
+#define PM_MODE0 (0<<1)
+#define PM_MODE1 (1<<1)
+#define PM_MODE2 (2<<1)
+#define PM_MODE3 (3<<1)
+#define PM_MODE4 (4<<1)
+#define PM_MODE5 (5<<1)
+#define PM_CNT_BINARY (0<<0)
+#define PM_CNT_BCD (1<<0)
+#define PM_READ_COUNTER0 (1<<1)
+#define PM_READ_COUNTER1 (1<<2)
+#define PM_READ_COUNTER2 (1<<3)
+#define PM_READ_STATUSVALUE (0<<4)
+#define PM_READ_VALUE (1<<4)
+#define PM_READ_STATUS (2<<4)
+
+
+/****************************************************************
+ * TSC timer
+ ****************************************************************/
+
+#define CALIBRATE_COUNT 0x800 // Approx 1.7ms
+
+u32 cpu_khz VAR16VISIBLE;
+u8 no_tsc VAR16VISIBLE;
static void
-init_rtc()
+calibrate_tsc(void)
{
- outb_cmos(0x26, CMOS_STATUS_A);
- outb_cmos(0x02, CMOS_STATUS_B);
- inb_cmos(CMOS_STATUS_C);
- inb_cmos(CMOS_STATUS_D);
+ u32 eax, ebx, ecx, edx, cpuid_features = 0;
+ cpuid(0, &eax, &ebx, &ecx, &edx);
+ if (eax > 0)
+ cpuid(1, &eax, &ebx, &ecx, &cpuid_features);
+
+ if (!(cpuid_features & CPUID_TSC)) {
+ SET_GLOBAL(no_tsc, 1);
+ SET_GLOBAL(cpu_khz, PIT_TICK_RATE / 1000);
+ dprintf(3, "386/486 class CPU. Using TSC emulation\n");
+ return;
+ }
+
+ // Setup "timer2"
+ u8 orig = inb(PORT_PS2_CTRLB);
+ outb((orig & ~PPCB_SPKR) | PPCB_T2GATE, PORT_PS2_CTRLB);
+ /* binary, mode 0, LSB/MSB, Ch 2 */
+ outb(PM_SEL_TIMER2|PM_ACCESS_WORD|PM_MODE0|PM_CNT_BINARY, PORT_PIT_MODE);
+ /* LSB of ticks */
+ outb(CALIBRATE_COUNT & 0xFF, PORT_PIT_COUNTER2);
+ /* MSB of ticks */
+ outb(CALIBRATE_COUNT >> 8, PORT_PIT_COUNTER2);
+
+ u64 start = rdtscll();
+ while ((inb(PORT_PS2_CTRLB) & PPCB_T2OUT) == 0)
+ ;
+ u64 end = rdtscll();
+
+ // Restore PORT_PS2_CTRLB
+ outb(orig, PORT_PS2_CTRLB);
+
+ // Store calibrated cpu khz.
+ u64 diff = end - start;
+ dprintf(6, "tsc calibrate start=%u end=%u diff=%u\n"
+ , (u32)start, (u32)end, (u32)diff);
+ u32 hz = diff * PIT_TICK_RATE / CALIBRATE_COUNT;
+ SET_GLOBAL(cpu_khz, hz / 1000);
+
+ dprintf(1, "CPU Mhz=%u\n", hz / 1000000);
+}
+
+static u64
+emulate_tsc(void)
+{
+ int cnt, d;
+ u16 ebda_seg = get_ebda_seg();
+ u64 ret;
+ /* read timer 0 current count */
+ ret = GET_EBDA2(ebda_seg, tsc_8254);
+ /* readback mode has slightly shifted registers, works on all 8254, readback PIT0 latch */
+ outb(PM_SEL_READBACK | PM_READ_VALUE | PM_READ_COUNTER0, PORT_PIT_MODE);
+ cnt = (inb(PORT_PIT_COUNTER0) | (inb(PORT_PIT_COUNTER0) << 8));
+ d = GET_EBDA2(ebda_seg, last_tsc_8254) - cnt;
+ /* Determine the ticks count from last invocation of this function */
+ ret += (d > 0) ? d : (PIT_TICK_INTERVAL + d);
+ SET_EBDA2(ebda_seg, last_tsc_8254, cnt);
+ SET_EBDA2(ebda_seg, tsc_8254, ret);
+ return ret;
}
-static u8
-rtc_updating()
+static u64
+get_tsc(void)
+{
+ if (unlikely(GET_GLOBAL(no_tsc)))
+ return emulate_tsc();
+ return rdtscll();
+}
+
+int
+check_tsc(u64 end)
+{
+ return (s64)(get_tsc() - end) > 0;
+}
+
+static void
+tscdelay(u64 diff)
+{
+ u64 start = get_tsc();
+ u64 end = start + diff;
+ while (!check_tsc(end))
+ cpu_relax();
+}
+
+static void
+tscsleep(u64 diff)
+{
+ u64 start = get_tsc();
+ u64 end = start + diff;
+ while (!check_tsc(end))
+ yield();
+}
+
+void ndelay(u32 count) {
+ tscdelay(count * GET_GLOBAL(cpu_khz) / 1000000);
+}
+void udelay(u32 count) {
+ tscdelay(count * GET_GLOBAL(cpu_khz) / 1000);
+}
+void mdelay(u32 count) {
+ tscdelay(count * GET_GLOBAL(cpu_khz));
+}
+
+void nsleep(u32 count) {
+ tscsleep(count * GET_GLOBAL(cpu_khz) / 1000000);
+}
+void usleep(u32 count) {
+ tscsleep(count * GET_GLOBAL(cpu_khz) / 1000);
+}
+void msleep(u32 count) {
+ tscsleep(count * GET_GLOBAL(cpu_khz));
+}
+
+// Return the TSC value that is 'msecs' time in the future.
+u64
+calc_future_tsc(u32 msecs)
+{
+ u32 khz = GET_GLOBAL(cpu_khz);
+ return get_tsc() + ((u64)khz * msecs);
+}
+u64
+calc_future_tsc_usec(u32 usecs)
+{
+ u32 khz = GET_GLOBAL(cpu_khz);
+ return get_tsc() + ((u64)(khz/1000) * usecs);
+}
+
+
+/****************************************************************
+ * Init
+ ****************************************************************/
+
+static int
+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.
// If it is set, it tries to wait until there is a transition
- // to 0, and will return 0 if such a transition occurs. A 1
+ // 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 244useconds.
- // The count I use below guarantees coverage or more than
- // this time, with any reasonable IPS setting.
-
- u16 count = 25000;
- while (--count != 0) {
- if ( (inb_cmos(CMOS_STATUS_A) & 0x80) == 0 )
+ // that this bit should be set is constrained to (1984+244)
+ // 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(15);
+ for (;;) {
+ if ((inb_cmos(CMOS_STATUS_A) & RTC_A_UIP) == 0)
return 0;
+ if (check_tsc(end))
+ // update-in-progress never transitioned to 0
+ return -1;
+ yield();
}
- return 1; // update-in-progress never transitioned to 0
+}
+
+static void
+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);
+ // maximum count of 0000H = 18.2Hz
+ outb(0x0, PORT_PIT_COUNTER0);
+ outb(0x0, PORT_PIT_COUNTER0);
+}
+
+static void
+init_rtc(void)
+{
+ outb_cmos(0x26, CMOS_STATUS_A); // 32,768Khz src, 976.5625us updates
+ u8 regB = inb_cmos(CMOS_STATUS_B);
+ outb_cmos((regB & RTC_B_DSE) | RTC_B_24HR, CMOS_STATUS_B);
+ inb_cmos(CMOS_STATUS_C);
+ inb_cmos(CMOS_STATUS_D);
+}
+
+static u32
+bcd2bin(u8 val)
+{
+ return (val & 0xf) + ((val >> 4) * 10);
+}
+
+void
+timer_setup(void)
+{
+ dprintf(3, "init timer\n");
+ calibrate_tsc();
+ pit_setup();
+
+ init_rtc();
+ rtc_updating();
+ u32 seconds = bcd2bin(inb_cmos(CMOS_RTC_SECONDS));
+ u32 minutes = bcd2bin(inb_cmos(CMOS_RTC_MINUTES));
+ u32 hours = bcd2bin(inb_cmos(CMOS_RTC_HOURS));
+ u32 ticks = (hours * 60 + minutes) * 60 + seconds;
+ ticks = ((u64)ticks * PIT_TICK_RATE) / PIT_TICK_INTERVAL;
+ SET_BDA(timer_counter, ticks);
+
+ 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;
regs->al = GET_BDA(timer_rollover);
SET_BDA(timer_rollover, 0); // reset flag
- set_cf(regs, 0);
+ set_success(regs);
}
// Set Current Clock Count
u32 ticks = (regs->cx << 16) | regs->dx;
SET_BDA(timer_counter, ticks);
SET_BDA(timer_rollover, 0); // reset flag
+ // XXX - should use set_code_success()?
regs->ah = 0;
- set_cf(regs, 0);
+ set_success(regs);
}
// Read CMOS Time
handle_1a02(struct bregs *regs)
{
if (rtc_updating()) {
- set_cf(regs, 1);
+ set_invalid(regs);
return;
}
regs->dh = inb_cmos(CMOS_RTC_SECONDS);
regs->cl = inb_cmos(CMOS_RTC_MINUTES);
regs->ch = inb_cmos(CMOS_RTC_HOURS);
- regs->dl = inb_cmos(CMOS_STATUS_B) & 0x01;
+ regs->dl = inb_cmos(CMOS_STATUS_B) & RTC_B_DSE;
regs->ah = 0;
regs->al = regs->ch;
- set_cf(regs, 0);
+ set_success(regs);
}
// Set CMOS Time
outb_cmos(regs->cl, CMOS_RTC_MINUTES);
outb_cmos(regs->ch, CMOS_RTC_HOURS);
// Set Daylight Savings time enabled bit to requested value
- u8 val8 = (inb_cmos(CMOS_STATUS_B) & 0x60) | 0x02 | (regs->dl & 0x01);
+ u8 val8 = ((inb_cmos(CMOS_STATUS_B) & (RTC_B_PIE|RTC_B_AIE))
+ | RTC_B_24HR | (regs->dl & RTC_B_DSE));
outb_cmos(val8, CMOS_STATUS_B);
regs->ah = 0;
regs->al = val8; // val last written to Reg B
- set_cf(regs, 0);
+ set_success(regs);
}
// Read CMOS Date
{
regs->ah = 0;
if (rtc_updating()) {
- set_cf(regs, 1);
+ set_invalid(regs);
return;
}
regs->cl = inb_cmos(CMOS_RTC_YEAR);
regs->dh = inb_cmos(CMOS_RTC_MONTH);
regs->dl = inb_cmos(CMOS_RTC_DAY_MONTH);
- regs->ch = inb_cmos(CMOS_CENTURY);
+ if (CONFIG_COREBOOT) {
+ if (regs->cl > 0x80)
+ regs->ch = 0x19;
+ else
+ regs->ch = 0x20;
+ } else {
+ regs->ch = inb_cmos(CMOS_CENTURY);
+ }
regs->al = regs->ch;
- set_cf(regs, 0);
+ set_success(regs);
}
// Set CMOS Date
// My assumption: RegB = (RegB & 01111111b)
if (rtc_updating()) {
init_rtc();
- set_cf(regs, 1);
+ set_invalid(regs);
return;
}
outb_cmos(regs->cl, CMOS_RTC_YEAR);
outb_cmos(regs->dh, CMOS_RTC_MONTH);
outb_cmos(regs->dl, CMOS_RTC_DAY_MONTH);
- outb_cmos(regs->ch, CMOS_CENTURY);
- u8 val8 = inb_cmos(CMOS_STATUS_B) & 0x7f; // clear halt-clock bit
+ if (!CONFIG_COREBOOT)
+ outb_cmos(regs->ch, CMOS_CENTURY);
+ // clear halt-clock bit
+ u8 val8 = inb_cmos(CMOS_STATUS_B) & ~RTC_B_SET;
outb_cmos(val8, CMOS_STATUS_B);
regs->ah = 0;
regs->al = val8; // AL = val last written to Reg B
- set_cf(regs, 0);
+ set_success(regs);
}
// Set Alarm Time in CMOS
// My assumption: RegB = ((RegB & 01111111b) | 00100000b)
u8 val8 = inb_cmos(CMOS_STATUS_B); // Get Status Reg B
regs->ax = 0;
- if (val8 & 0x20) {
+ if (val8 & RTC_B_AIE) {
// Alarm interrupt enabled already
- set_cf(regs, 1);
+ set_invalid(regs);
return;
}
if (rtc_updating()) {
outb_cmos(regs->dh, CMOS_RTC_SECONDS_ALARM);
outb_cmos(regs->cl, CMOS_RTC_MINUTES_ALARM);
outb_cmos(regs->ch, CMOS_RTC_HOURS_ALARM);
- outb(inb(PORT_PIC2_DATA) & ~PIC2_IRQ8, PORT_PIC2_DATA); // enable IRQ 8
// enable Status Reg B alarm bit, clear halt clock bit
- outb_cmos((val8 & 0x7f) | 0x20, CMOS_STATUS_B);
- set_cf(regs, 0);
+ outb_cmos((val8 & ~RTC_B_SET) | RTC_B_AIE, CMOS_STATUS_B);
+ set_success(regs);
}
// Turn off Alarm
// My assumption: RegB = (RegB & 01010111b)
u8 val8 = inb_cmos(CMOS_STATUS_B); // Get Status Reg B
// clear clock-halt bit, disable alarm bit
- outb_cmos(val8 & 0x57, CMOS_STATUS_B); // disable alarm bit
+ outb_cmos(val8 & ~(RTC_B_SET|RTC_B_AIE), CMOS_STATUS_B);
regs->ah = 0;
regs->al = val8; // val last written to Reg B
- set_cf(regs, 0);
-}
-
-static void
-handle_1ab1(struct bregs *regs)
-{
- // XXX - pcibios stuff
- set_cf(regs, 1);
+ set_success(regs);
}
// Unsupported
static void
handle_1aXX(struct bregs *regs)
{
- set_cf(regs, 1);
+ set_unimplemented(regs);
}
// INT 1Ah Time-of-day Service Entry Point
-void VISIBLE
+void VISIBLE16
handle_1a(struct bregs *regs)
{
- //debug_enter(regs);
+ debug_enter(regs, DEBUG_HDL_1a);
switch (regs->ah) {
case 0x00: handle_1a00(regs); break;
case 0x01: handle_1a01(regs); break;
case 0xb1: handle_1ab1(regs); break;
default: handle_1aXX(regs); break;
}
- debug_exit(regs);
-}
-
-// User Timer Tick
-void VISIBLE
-handle_1c(struct bregs *regs)
-{
- //debug_enter(regs);
}
// INT 08h System Timer ISR Entry Point
-void VISIBLE
-handle_08(struct bregs *regs)
+void VISIBLE16
+handle_08(void)
{
-// debug_enter(regs);
+ debug_isr(DEBUG_ISR_08);
floppy_tick();
u32 counter = GET_BDA(timer_counter);
counter++;
// compare to one days worth of timer ticks at 18.2 hz
- if (counter >= 0x001800B0) {
+ if (counter >= TICKS_PER_DAY) {
// there has been a midnight rollover at this point
counter = 0;
SET_BDA(timer_rollover, GET_BDA(timer_rollover) + 1);
SET_BDA(timer_counter, counter);
+ usb_check_event();
+
// chain to user timer tick INT #0x1c
- struct bregs br;
- memset(&br, 0, sizeof(br));
- call16_int(0x1c, &br);
+ u32 eax=0, flags;
+ call16_simpint(0x1c, &eax, &flags);
+
+ eoi_pic1();
+}
+
+
+/****************************************************************
+ * 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)
+{
+ if (GET_BDA(rtc_wait_flag) & RWS_WAIT_PENDING)
+ return -1;
+
+ // Interval not already set.
+ 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);
+ useRTC();
+ return 0;
+}
+
+static void
+clear_usertimer(void)
+{
+ if (!(GET_BDA(rtc_wait_flag) & RWS_WAIT_PENDING))
+ return;
+ // Turn off status byte.
+ SET_BDA(rtc_wait_flag, 0);
+ releaseRTC();
+}
+
+#define RET_ECLOCKINUSE 0x83
- eoi_master_pic();
+// Wait for CX:DX microseconds
+void
+handle_1586(struct bregs *regs)
+{
+ // Use the rtc to wait for the specified time.
+ u8 statusflag = 0;
+ u32 count = (regs->cx << 16) | regs->dx;
+ int ret = set_usertimer(count, GET_SEG(SS), (u32)&statusflag);
+ if (ret) {
+ set_code_invalid(regs, RET_ECLOCKINUSE);
+ return;
+ }
+ while (!statusflag)
+ wait_irq();
+ set_success(regs);
}
// Set Interval requested.
static void
handle_158300(struct bregs *regs)
{
- if (GET_BDA(rtc_wait_flag) & RWS_WAIT_PENDING) {
+ int ret = set_usertimer((regs->cx << 16) | regs->dx, regs->es, regs->bx);
+ if (ret)
// Interval already set.
- DEBUGF("int15: Func 83h, failed, already waiting.\n" );
- handle_ret(regs, RET_EUNSUPPORTED);
- }
- // Interval not already set.
- SET_BDA(rtc_wait_flag, RWS_WAIT_PENDING); // Set status byte.
- u32 v = (regs->es << 16) | regs->bx;
- SET_BDA(ptr_user_wait_complete_flag, v);
- v = (regs->dx << 16) | regs->cx;
- SET_BDA(user_wait_timeout, v);
-
- // Unmask IRQ8 so INT70 will get through.
- u8 irqDisable = inb(PORT_PIC2_DATA);
- outb(irqDisable & ~PIC2_IRQ8, PORT_PIC2_DATA);
- // Turn on the Periodic Interrupt timer
- u8 bRegister = inb_cmos(CMOS_STATUS_B);
- outb_cmos(CMOS_STATUS_B, bRegister | CSB_EN_ALARM_IRQ);
-
- set_cf(regs, 0); // XXX - no set ah?
+ set_code_invalid(regs, RET_EUNSUPPORTED);
+ else
+ set_success(regs);
}
// Clear interval requested
static void
handle_158301(struct bregs *regs)
{
- SET_BDA(rtc_wait_flag, 0); // Clear status byte
- // Turn off the Periodic Interrupt timer
- u8 bRegister = inb_cmos(CMOS_STATUS_B);
- outb_cmos(CMOS_STATUS_B, bRegister & ~CSB_EN_ALARM_IRQ);
- set_cf(regs, 0); // XXX - no set ah?
+ clear_usertimer();
+ set_success(regs);
}
static void
handle_1583XX(struct bregs *regs)
{
+ set_code_unimplemented(regs, RET_EUNSUPPORTED);
regs->al--;
- handle_ret(regs, RET_EUNSUPPORTED);
}
void
}
}
+#define USEC_PER_RTC DIV_ROUND_CLOSEST(1000000, 1024)
+
// int70h: IRQ8 - CMOS RTC
-void VISIBLE
-handle_70(struct bregs *regs)
+void VISIBLE16
+handle_70(void)
{
- debug_enter(regs);
+ debug_isr(DEBUG_ISR_70);
// Check which modes are enabled and have occurred.
u8 registerB = inb_cmos(CMOS_STATUS_B);
u8 registerC = inb_cmos(CMOS_STATUS_C);
- if (!(registerB & 0x60))
+ if (!(registerB & (RTC_B_PIE|RTC_B_AIE)))
goto done;
- if (registerC & 0x20) {
+ if (registerC & RTC_B_AIE) {
// Handle Alarm Interrupt.
- struct bregs br;
- memset(&br, 0, sizeof(br));
- call16_int(0x4a, &br);
+ u32 eax=0, flags;
+ call16_simpint(0x4a, &eax, &flags);
}
- if (!(registerC & 0x40))
+ if (!(registerC & RTC_B_PIE))
goto done;
// Handle Periodic Interrupt.
+ check_preempt();
+
if (!GET_BDA(rtc_wait_flag))
goto done;
// Wait Interval (Int 15, AH=83) active.
u32 time = GET_BDA(user_wait_timeout); // Time left in microseconds.
- if (time < 0x3D1) {
- // Done waiting.
- u32 segoff = GET_BDA(ptr_user_wait_complete_flag);
- u16 segment = segoff >> 16;
- u16 offset = segoff & 0xffff;
- // Turn off status byte.
- SET_BDA(rtc_wait_flag, 0);
- // Clear the Periodic Interrupt.
- outb_cmos(registerB & 0x37, CMOS_STATUS_B);
- // Write to specified flag byte.
- u8 oldval = GET_FARVAR(segment, *(u8*)(offset+0));
- SET_FARVAR(segment, *(u8*)(offset+0), oldval | 0x80);
+ if (time < USEC_PER_RTC) {
+ // Done waiting - write to specified flag byte.
+ struct segoff_s segoff = GET_BDA(user_wait_complete_flag);
+ u16 ptr_seg = segoff.seg;
+ u8 *ptr_far = (u8*)(segoff.offset+0);
+ u8 oldval = GET_FARVAR(ptr_seg, *ptr_far);
+ SET_FARVAR(ptr_seg, *ptr_far, oldval | 0x80);
+
+ clear_usertimer();
} else {
// Continue waiting.
- time -= 0x3D1;
+ time -= USEC_PER_RTC;
SET_BDA(user_wait_timeout, time);
}
done:
- eoi_both_pics();
+ eoi_pic2();
}