Hi all:
I found that reading the cmos can not get the physical memory size up to
64M. So I choose to use "int 15" to detect and below is my function. But I
found that every time the result is different. Sometimes, it is even bigger
than the actual size of my physical memory.... Whether it will return the
result of current usable physical memory or the whole memory? I know that
when booting the kernel, usable memory is approximately equal to the whole
memory. But how can I detect the whole size when using the kernel module?
And another problem is that when I insmod it the third time, the keyboard
and mouse don't work and lock. How to deal with such problem and what will
be the root cause of it.
Thanks
void
detect_memory(void)
{
uint32_t mem = 0;
uint32_t low = 0;
__asm __volatile("movw $0xE801, %%ax\n\t"
"int $0x15\n\t"
"movw %%ax, %%cx\n\t"
"movw %%bx, %%dx\n\t"
"andl $0xffff, %%edx\n\t"
"shll $6, %%edx\n\t"
"andl $0xffff, %%ecx\n\t"
"addl %%ecx, %%edx"
:"=c"(low),"=d"(mem):"c"(low),"d"(mem));
printk("total memory %dkb,low memory %dkb\n",mem,low);
}
--
Gu, Zhongshu（顾钟蔬）
