// Misc utility functions.
//
-// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2008,2009 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU LGPLv3 license.
-#include "util.h" // usleep
+#include "util.h" // call16
#include "bregs.h" // struct bregs
-#include "config.h" // SEG_BIOS
-#include "farptr.h" // GET_FARPTR
+#include "farptr.h" // GET_FLATPTR
#include "biosvar.h" // get_ebda_seg
// Call a function with a specified register state. Note that on
asm volatile(
#if MODE16 == 1
"calll __call16\n"
+ "cli\n"
+ "cld"
#else
- "calll __call16_from32\n"
+ "calll __call16_from32"
#endif
: "+a" (callregs), "+m" (*callregs)
:
- : "ebx", "ecx", "edx", "esi", "edi", "ebp", "cc", "memory");
+ : "ebx", "ecx", "edx", "esi", "edi", "cc", "memory");
}
inline void
call16big(struct bregs *callregs)
{
- extern void __force_link_error__call16big_only_in_32bit_mode();
- if (MODE16)
- __force_link_error__call16big_only_in_32bit_mode();
-
+ ASSERT32();
asm volatile(
- "calll __call16big_from32\n"
+ "calll __call16big_from32"
: "+a" (callregs), "+m" (*callregs)
:
- : "ebx", "ecx", "edx", "esi", "edi", "ebp", "cc", "memory");
+ : "ebx", "ecx", "edx", "esi", "edi", "cc", "memory");
}
inline void
__call16_int(struct bregs *callregs, u16 offset)
{
- callregs->cs = SEG_BIOS;
- callregs->ip = offset;
+ if (MODE16)
+ callregs->code.seg = GET_SEG(CS);
+ else
+ callregs->code.seg = SEG_BIOS;
+ callregs->code.offset = offset;
call16(callregs);
}
-inline void
-call16_simpint(int nr, u32 *eax, u32 *flags)
-{
- extern void __force_link_error__call16_simpint_only_in_16bit_mode();
- if (!MODE16)
- __force_link_error__call16_simpint_only_in_16bit_mode();
-
- asm volatile(
- "stc\n"
- "int %2\n"
- "pushfl\n"
- "popl %1\n"
- "cld\n"
- "cli\n"
- : "+a"(*eax), "=r"(*flags)
- : "i"(nr)
- : "cc", "memory");
-}
-
// Switch to the extra stack in ebda and call a function.
inline u32
stack_hop(u32 eax, u32 edx, u32 ecx, void *func)
{
- extern void __force_link_error__stack_hop_only_in_16bit_mode();
- if (!MODE16)
- __force_link_error__stack_hop_only_in_16bit_mode();
-
- u32 ebda_seg = get_ebda_seg();
- u32 tmp;
+ ASSERT16();
+ u16 ebda_seg = get_ebda_seg(), bkup_ss;
+ u32 bkup_esp;
asm volatile(
- // Backup current %ss value.
- "movl %%ss, %4\n"
- // Copy ebda seg to %ss and %ds
- "movl %3, %%ss\n"
- "movl %3, %%ds\n"
- // Backup %esp and set it to new value
- "movl %%esp, %3\n"
+ // Backup current %ss/%esp values.
+ "movw %%ss, %w3\n"
+ "movl %%esp, %4\n"
+ // Copy ebda seg to %ds/%ss and set %esp
+ "movw %w6, %%ds\n"
+ "movw %w6, %%ss\n"
"movl %5, %%esp\n"
// Call func
- "calll %6\n"
+ "calll %7\n"
// Restore segments and stack
- "movl %3, %%esp\n"
- "movl %4, %%ss\n"
- "movl %4, %%ds\n"
- : "+a" (eax), "+d" (edx), "+c" (ecx), "+r" (ebda_seg), "=r" (tmp)
- : "i" (EBDA_OFFSET_TOP_STACK), "m" (*(u8*)func)
+ "movw %w3, %%ds\n"
+ "movw %w3, %%ss\n"
+ "movl %4, %%esp"
+ : "+a" (eax), "+d" (edx), "+c" (ecx), "=&r" (bkup_ss), "=&r" (bkup_esp)
+ : "i" (EBDA_OFFSET_TOP_STACK), "r" (ebda_seg), "m" (*(u8*)func)
: "cc", "memory");
return eax;
}
// Sum the bytes in the specified area.
u8
-checksum(u8 *far_data, u32 len)
+checksum_far(u16 buf_seg, void *buf_far, u32 len)
{
+ SET_SEG(ES, buf_seg);
u32 i;
u8 sum = 0;
for (i=0; i<len; i++)
- sum += GET_FARPTR(far_data[i]);
+ sum += GET_VAR(ES, ((u8*)buf_far)[i]);
return sum;
}
+u8
+checksum(void *buf, u32 len)
+{
+ return checksum_far(GET_SEG(SS), buf, len);
+}
+
+size_t
+strlen(const char *s)
+{
+ if (__builtin_constant_p(s))
+ return __builtin_strlen(s);
+ const char *p = s;
+ while (*p)
+ p++;
+ return p-s;
+}
+
+// Compare two areas of memory.
+int
+memcmp(const void *s1, const void *s2, size_t n)
+{
+ while (n) {
+ if (*(u8*)s1 != *(u8*)s2)
+ return *(u8*)s1 < *(u8*)s2 ? -1 : 1;
+ s1++;
+ s2++;
+ n--;
+ }
+ return 0;
+}
+
+// Compare two strings.
+int
+strcmp(const char *s1, const char *s2)
+{
+ for (;;) {
+ if (*s1 != *s2)
+ return *s1 < *s2 ? -1 : 1;
+ if (! *s1)
+ return 0;
+ s1++;
+ s2++;
+ }
+}
+
+inline void
+memset_far(u16 d_seg, void *d_far, u8 c, size_t len)
+{
+ SET_SEG(ES, d_seg);
+ asm volatile(
+ "rep stosb %%es:(%%di)"
+ : "+c"(len), "+D"(d_far)
+ : "a"(c)
+ : "cc", "memory");
+}
+
+inline void
+memset16_far(u16 d_seg, void *d_far, u16 c, size_t len)
+{
+ len /= 2;
+ SET_SEG(ES, d_seg);
+ asm volatile(
+ "rep stosw %%es:(%%di)"
+ : "+c"(len), "+D"(d_far)
+ : "a"(c)
+ : "cc", "memory");
+}
+
void *
memset(void *s, int c, size_t n)
{
return s;
}
-void *
-memcpy_far(void *far_d1, const void *far_s1, size_t len)
+inline void
+memcpy_far(u16 d_seg, void *d_far, u16 s_seg, const void *s_far, size_t len)
{
- u8 *d = far_d1;
- u8 *s = (u8*)far_s1;
-
- while (len--) {
- SET_FARPTR(*d, GET_FARPTR(*s));
- d++;
- s++;
- }
-
- return far_d1;
+ SET_SEG(ES, d_seg);
+ u16 bkup_ds;
+ asm volatile(
+ "movw %%ds, %w0\n"
+ "movw %w4, %%ds\n"
+ "rep movsb (%%si),%%es:(%%di)\n"
+ "movw %w0, %%ds"
+ : "=&r"(bkup_ds), "+c"(len), "+S"(s_far), "+D"(d_far)
+ : "r"(s_seg)
+ : "cc", "memory");
}
void *
+#undef memcpy
memcpy(void *d1, const void *s1, size_t len)
+#if MODE16 == 0
+#define memcpy __builtin_memcpy
+#endif
{
- u8 *d = (u8*)d1, *s = (u8*)s1;
- while (len--)
- *d++ = *s++;
+ SET_SEG(ES, GET_SEG(SS));
+ void *d = d1;
+ if (((u32)d1 | (u32)s1 | len) & 3) {
+ // non-aligned memcpy
+ asm volatile(
+ "rep movsb (%%esi),%%es:(%%edi)"
+ : "+c"(len), "+S"(s1), "+D"(d)
+ : : "cc", "memory");
+ return d1;
+ }
+ // Common case - use 4-byte copy
+ len /= 4;
+ asm volatile(
+ "rep movsl (%%esi),%%es:(%%edi)"
+ : "+c"(len), "+S"(s1), "+D"(d)
+ : : "cc", "memory");
return d1;
}
return d;
}
+
+// Copy a string - truncating it if necessary.
+char *
+strtcpy(char *dest, const char *src, size_t len)
+{
+ char *d = dest;
+ while (len-- && *src != '\0')
+ *d++ = *src++;
+ *d = '\0';
+ return dest;
+}
+
+// Wait for 'usec' microseconds with irqs enabled.
+void
+usleep(u32 usec)
+{
+ struct bregs br;
+ memset(&br, 0, sizeof(br));
+ br.ah = 0x86;
+ br.cx = usec >> 16;
+ br.dx = usec;
+ call16_int(0x15, &br);
+}
+
+// See if a keystroke is pending in the keyboard buffer.
+static int
+check_for_keystroke()
+{
+ struct bregs br;
+ memset(&br, 0, sizeof(br));
+ br.ah = 1;
+ call16_int(0x16, &br);
+ return !(br.flags & F_ZF);
+}
+
+// Return a keystroke - waiting forever if necessary.
+static int
+get_raw_keystroke()
+{
+ struct bregs br;
+ memset(&br, 0, sizeof(br));
+ call16_int(0x16, &br);
+ return br.ah;
+}
+
+// Read a keystroke - waiting up to 'msec' milliseconds.
+int
+get_keystroke(int msec)
+{
+ for (;;) {
+ if (check_for_keystroke())
+ return get_raw_keystroke();
+ if (msec <= 0)
+ return -1;
+ usleep(50*1000);
+ msec -= 50;
+ }
+}
projects / seabios.git / blobdiff