/* Open WSS for usage */
boolean wss_open()
{
__dpmi_meminfo struct_info;
if (!wss.ok)
if (!wss_detect())
return FALSE;
if (wss.open)
return FALSE;
/* Now lock the wss structure in memory */
struct_info.address = __djgpp_base_address + (unsigned long)&wss;
struct_info.size = sizeof(wss);
if (__dpmi_lock_linear_region(&struct_info))
return FALSE;
/* Hook the WSS IRQ */
wss.irq_handle =
irq_hook(wss.irq, wss_irq, (long)wss_irq_end - (long)wss_irq);
if (!wss.irq_handle) {
__dpmi_unlock_linear_region(&struct_info);
return FALSE;
}
/* Enable the interrupt */
irq_enable(wss.irq_handle);
if (wss.irq > 7)
_irq_enable(2);
wss.open++;
return TRUE;
}
void
dpmi_lock_memory (void *start, unsigned long num_bytes)
{
unsigned long base = 0;
/* Get the linear base address. */
if (__dpmi_get_segment_base_address (dos_pm_ds, &base) != -1)
{
__dpmi_meminfo mem;
mem.handle = 0; /* Unused */
mem.size = num_bytes;
mem.address = (unsigned long) ((char *) start + base);
__dpmi_lock_linear_region (&mem);
}
}
int dma_initialize()
{
if (!__djgpp_nearptr_enable())
return 0;
/* Trick: Avoid re-setting DS selector limit on each memory allocation
call */
__djgpp_selector_limit = 0xffffffff;
__locked_data.address = __djgpp_base_address + (unsigned long)&dma;
__locked_data.size = sizeof(dma);
if (__dpmi_lock_linear_region(&__locked_data))
return 0;
return (__initialized = 1);
}
void *dos_getmaxlockedmem(int *size)
{
__dpmi_free_mem_info meminfo;
__dpmi_meminfo info;
int working_size;
void *working_memory;
int last_locked;
int extra, i, j, allocsize;
static char *msg = "Locking data...";
int m, n;
byte *x;
// first lock all the current executing image so the locked count will
// be accurate. It doesn't hurt to lock the memory multiple times
last_locked = __djgpp_selector_limit + 1;
info.size = last_locked - 4096;
info.address = __djgpp_base_address + 4096;
if (lockmem)
{
if(__dpmi_lock_linear_region(&info))
{
Sys_Error ("Lock of current memory at 0x%lx for %ldKb failed!\n",
info.address, info.size/1024);
}
}
__dpmi_get_free_memory_information(&meminfo);
if (!win95) /* Not windows or earlier than Win95 */
{
working_size = meminfo.maximum_locked_page_allocation_in_pages * 4096;
}
else
{
working_size = meminfo.largest_available_free_block_in_bytes -
LEAVE_FOR_CACHE;
}
working_size &= ~0xffff; /* Round down to 64K */
working_size += 0x10000;
do
{
working_size -= 0x10000; /* Decrease 64K and try again */
working_memory = sbrk(working_size);
} while (working_memory == (void *)-1);
extra = 0xfffc - ((unsigned)sbrk(0) & 0xffff);
if (extra > 0)
{
sbrk(extra);
working_size += extra;
}
// now grab the memory
info.address = last_locked + __djgpp_base_address;
if (!win95)
{
info.size = __djgpp_selector_limit + 1 - last_locked;
while (info.size > 0 && __dpmi_lock_linear_region(&info))
{
info.size -= 0x1000;
working_size -= 0x1000;
sbrk(-0x1000);
}
}
else
{ /* Win95 section */
j = COM_CheckParm("-winmem");
if (standard_quake)
minmem = MINIMUM_WIN_MEMORY;
else
minmem = MINIMUM_WIN_MEMORY_LEVELPAK;
if (j)
{
allocsize = ((int)(Q_atoi(com_argv[j+1]))) * 0x100000 +
LOCKED_FOR_MALLOC;
if (allocsize < (minmem + LOCKED_FOR_MALLOC))
allocsize = minmem + LOCKED_FOR_MALLOC;
}
else
{
allocsize = minmem + LOCKED_FOR_MALLOC;
}
if (!lockmem)
{
// we won't lock, just sbrk the memory
info.size = allocsize;
goto UpdateSbrk;
}
// lock the memory down
write (STDOUT, msg, strlen (msg));
for (j=allocsize ; j>(minmem + LOCKED_FOR_MALLOC) ;
j -= 0x100000)
{
info.size = j;
if (!__dpmi_lock_linear_region(&info))
goto Locked;
write (STDOUT, ".", 1);
}
// finally, try with the absolute minimum amount
for (i=0 ; i<10 ; i++)
{
info.size = minmem + LOCKED_FOR_MALLOC;
if (!__dpmi_lock_linear_region(&info))
goto Locked;
}
Sys_Error ("Can't lock memory; %d Mb lockable RAM required. "
"Try shrinking smartdrv.", info.size / 0x100000);
Locked:
UpdateSbrk:
info.address += info.size;
info.address -= __djgpp_base_address + 4; // ending point, malloc align
working_size = info.address - (int)working_memory;
sbrk(info.address-(int)sbrk(0)); // negative adjustment
}
if (lockunlockmem)
{
__dpmi_unlock_linear_region (&info);
printf ("Locked and unlocked %d Mb data\n", working_size / 0x100000);
}
else if (lockmem)
{
printf ("Locked %d Mb data\n", working_size / 0x100000);
}
else
{
printf ("Allocated %d Mb data\n", working_size / 0x100000);
}
// touch all the memory to make sure it's there. The 16-page skip is to
// keep Win 95 from thinking we're trying to page ourselves in (we are
// doing that, of course, but there's no reason we shouldn't)
x = (byte *)working_memory;
for (n=0 ; n<4 ; n++)
{
for (m=0 ; m<(working_size - 16 * 0x1000) ; m += 4)
{
sys_checksum += *(int *)&x[m];
sys_checksum += *(int *)&x[m + 16 * 0x1000];
}
}
// give some of what we locked back for malloc before returning. Done
// by cheating and passing a negative value to sbrk
working_size -= LOCKED_FOR_MALLOC;
sbrk( -(LOCKED_FOR_MALLOC));
*size = working_size;
return working_memory;
}
dma_buffer *dma_allocate(unsigned int channel, unsigned int size)
{
int parsize = (size + 15) >> 4; /* size in paragraphs */
int par = 0; /* Real-mode paragraph */
int selector = 0; /* Protected-mode selector */
int mask = channel <= 3 ? 0xfff : 0x1fff; /* Alignment mask in para. */
int allocsize = parsize; /* Allocated size in paragraphs */
int count; /* Try count */
int bound = 0; /* Nearest bound address */
int maxsize; /* Maximal possible block size */
dma_buffer *buffer = NULL;
__dpmi_meminfo buff_info, struct_info;
if (!dma_initialize())
return NULL;
/* Loop until we'll get a properly aligned memory block */
for (count = 8; count; count--) {
int resize = (selector != 0);
/* Try first to resize (possibly previously) allocated block */
if (resize) {
maxsize = (bound + parsize) - par;
if (maxsize > parsize * 2)
maxsize = parsize * 2;
if (maxsize == allocsize)
resize = 0;
else {
allocsize = maxsize;
/* BUG WARNING: there is an error in dpmi.h DJGPP 2.01 library:
the order of "selector" and "alloc size" should be
reversed */
if (__dpmi_resize_dos_memory(allocsize, selector, &maxsize) !=
0) resize = 0;
}
}
if (!resize) {
if (selector)
__dpmi_free_dos_memory(selector), selector = 0;
par = __dpmi_allocate_dos_memory(allocsize, &selector);
}
if ((par == 0) || (par == -1))
goto exit;
/* If memory block contains a properly aligned portion, quit loop */
bound = (par + mask + 1) & ~mask;
if (par + parsize <= bound)
break;
if (bound + parsize <= par + allocsize) {
par = bound;
break;
}
}
if (!count) {
__dpmi_free_dos_memory(selector);
goto exit;
}
buffer = malloc(sizeof(dma_buffer));
buffer->linear = (void *)(__djgpp_conventional_base + bound * 16);
buffer->physical = bound * 16;
buffer->size = parsize * 16;
buffer->selector = selector;
buffer->channel = channel;
buff_info.address = buffer->physical;
buff_info.size = buffer->size;
/*
Don't pay attention to return code since under plain DOS it often
returns error (at least under HIMEM/CWSDPMI and EMM386/DPMI)
*/
__dpmi_lock_linear_region(&buff_info);
/* Lock the DMA buffer control structure as well */
struct_info.address = __djgpp_base_address + (unsigned long)buffer;
struct_info.size = sizeof(dma_buffer);
if (__dpmi_lock_linear_region(&struct_info)) {
__dpmi_unlock_linear_region(&buff_info);
__dpmi_free_dos_memory(selector);
free(buffer);
buffer = NULL;
goto exit;
}
exit:
if (buffer)
__buffer_count++;
else if (--__buffer_count == 0)
dma_finalize();
return buffer;
}