#include "util.h" // dprintf
#include "bregs.h" // CR0_PE
+static inline u32 getcr0(void) {
+ u32 cr0;
+ asm("movl %%cr0, %0" : "=r"(cr0));
+ return cr0;
+}
+static inline void sgdt(struct descloc_s *desc) {
+ asm("sgdtl %0" : "=m"(*desc));
+}
+static inline void lgdt(struct descloc_s *desc) {
+ asm("lgdtl %0" : : "m"(*desc) : "memory");
+}
+
+// Call a 32bit SeaBIOS function from a 16bit SeaBIOS function.
+static inline int
+call32(void *func)
+{
+ ASSERT16();
+ u32 cr0 = getcr0();
+ if (cr0 & CR0_PE)
+ // Called in 16bit protected mode?!
+ return -1;
+
+ // Backup cmos index register and disable nmi
+ u8 cmosindex = inb(PORT_CMOS_INDEX);
+ outb(cmosindex | NMI_DISABLE_BIT, PORT_CMOS_INDEX);
+ inb(PORT_CMOS_DATA);
+
+ // Backup fs/gs and gdt
+ u16 fs = GET_SEG(FS), gs = GET_SEG(GS);
+ struct descloc_s gdt;
+ sgdt(&gdt);
+
+ func -= BUILD_BIOS_ADDR;
+ u32 bkup_ss, bkup_esp;
+ asm volatile(
+ // Backup ss/esp / set esp to flat stack location
+ " movl %%ss, %0\n"
+ " movl %%esp, %1\n"
+ " shll $4, %0\n"
+ " addl %0, %%esp\n"
+ " movl %%ss, %0\n"
+
+ // Transition to 32bit mode, call func, return to 16bit
+ " pushl $(" __stringify(BUILD_BIOS_ADDR) " + 1f)\n"
+ " jmp transition32\n"
+ " .code32\n"
+ "1:calll %2\n"
+ " pushl $2f\n"
+ " jmp transition16big\n"
+
+ // Restore ds/ss/esp
+ " .code16gcc\n"
+ "2:movl %0, %%ds\n"
+ " movl %0, %%ss\n"
+ " movl %1, %%esp\n"
+ : "=&r" (bkup_ss), "=&r" (bkup_esp)
+ : "m" (*(u8*)func)
+ : "eax", "ecx", "edx", "cc", "memory");
+
+ // Restore gdt and fs/gs
+ lgdt(&gdt);
+ SET_SEG(FS, fs);
+ SET_SEG(GS, gs);
+
+ // Restore cmos index register
+ outb(cmosindex, PORT_CMOS_INDEX);
+ inb(PORT_CMOS_DATA);
+ return 0;
+}
+
/****************************************************************
* Stack in EBDA
int VAR16VISIBLE CanPreempt;
void
-thread_setup()
+thread_setup(void)
{
MainThread.next = &MainThread;
MainThread.stackpos = NULL;
// Return the 'struct thread_info' for the currently running thread.
struct thread_info *
-getCurThread()
+getCurThread(void)
{
u32 esp = getesp();
if (esp <= BUILD_STACK_ADDR)
switch_next(struct thread_info *cur)
{
struct thread_info *next = cur->next;
+ if (cur == next)
+ // Nothing to do.
+ return;
asm volatile(
" pushl $1f\n" // store return pc
" pushl %%ebp\n" // backup %ebp
// Briefly permit irqs to occur.
void
-yield()
+yield(void)
{
- if (MODE16 || !CONFIG_THREADS) {
+ if (MODESEGMENT || !CONFIG_THREADS) {
// Just directly check irqs.
check_irqs();
return;
void
run_thread(void (*func)(void*), void *data)
{
- ASSERT32();
+ ASSERT32FLAT();
if (! CONFIG_THREADS)
goto fail;
struct thread_info *thread;
// Wait for all threads (other than the main thread) to complete.
void
-wait_threads()
+wait_threads(void)
{
- ASSERT32();
+ ASSERT32FLAT();
if (! CONFIG_THREADS)
return;
while (MainThread.next != &MainThread)
// Turn on RTC irqs and arrange for them to check the 32bit threads.
void
-start_preempt()
+start_preempt(void)
{
if (! CONFIG_THREADS || ! CONFIG_THREAD_OPTIONROMS)
return;
// Turn off RTC irqs / stop checking for thread execution.
void
-finish_preempt()
+finish_preempt(void)
{
if (! CONFIG_THREADS || ! CONFIG_THREAD_OPTIONROMS)
return;
dprintf(1, "Done preempt - %d checks\n", PreemptCount);
}
-static inline u32 getcr0() {
- u32 cr0;
- asm("movl %%cr0, %0" : "=r"(cr0));
- return cr0;
-}
-static inline void sgdt(struct descloc_s *desc) {
- asm("sgdtl %0" : "=m"(*desc));
-}
-static inline void lgdt(struct descloc_s *desc) {
- asm("lgdtl %0" : : "m"(*desc) : "memory");
-}
-
-#if !MODE16
+extern void yield_preempt(void);
+#if MODESEGMENT == 0
// Try to execute 32bit threads.
-void VISIBLE32
-yield_preempt()
+void VISIBLE32FLAT
+yield_preempt(void)
{
PreemptCount++;
switch_next(&MainThread);
// 16bit code that checks if threads are pending and executes them if so.
void
-check_preempt()
+check_preempt(void)
{
- ASSERT16();
if (! CONFIG_THREADS || ! CONFIG_THREAD_OPTIONROMS
|| !GET_GLOBAL(CanPreempt)
|| GET_GLOBAL(MainThread.next) == &MainThread)
return;
- u32 cr0 = getcr0();
- if (cr0 & CR0_PE)
- // Called in 16bit protected mode?!
- return;
-
- // Backup cmos index register and disable nmi
- u8 cmosindex = inb(PORT_CMOS_INDEX);
- outb(cmosindex | NMI_DISABLE_BIT, PORT_CMOS_INDEX);
- inb(PORT_CMOS_DATA);
- // Backup fs/gs and gdt
- u16 fs = GET_SEG(FS), gs = GET_SEG(GS);
- struct descloc_s gdt;
- sgdt(&gdt);
-
- u32 bkup_ss, bkup_esp;
- asm volatile(
- // Backup ss/esp / set esp to flat stack location
- " movl %%ss, %0\n"
- " movl %%esp, %1\n"
- " shll $4, %0\n"
- " addl %0, %%esp\n"
- " movl %%ss, %0\n"
-
- // Transition to 32bit mode, call yield_preempt, return to 16bit
- " pushl $(" __stringify(BUILD_BIOS_ADDR) " + 1f)\n"
- " jmp transition32\n"
- " .code32\n"
- "1:calll (yield_preempt - " __stringify(BUILD_BIOS_ADDR) ")\n"
- " pushl $2f\n"
- " jmp transition16big\n"
- " .code16gcc\n"
- "2:\n"
-
- // Restore ds/ss/esp
- " movl %0, %%ds\n"
- " movl %0, %%ss\n"
- " movl %1, %%esp\n"
- : "=&r" (bkup_ss), "=&r" (bkup_esp)
- : : "eax", "ecx", "edx", "cc", "memory");
-
- // Restore gdt and fs/gs
- lgdt(&gdt);
- SET_SEG(FS, fs);
- SET_SEG(GS, gs);
-
- // Restore cmos index register
- outb(cmosindex, PORT_CMOS_INDEX);
- inb(PORT_CMOS_DATA);
+ call32(yield_preempt);
}
projects / seabios.git / blobdiff