134 lines
3 KiB
C++
134 lines
3 KiB
C++
#include "pmm.hpp"
|
|
#include <base.hpp>
|
|
enum class DEVICETYPE: uint8_t {
|
|
PC,
|
|
CONSOLE,
|
|
EMBEDDED
|
|
};
|
|
enum class CPUARCH: uint8_t {
|
|
X86,
|
|
X86_64,
|
|
ARM
|
|
};
|
|
enum class ENDIAN: uint8_t {
|
|
BIG,
|
|
LITTLE
|
|
};
|
|
enum class PERM: uint8_t {
|
|
NONE,
|
|
X,
|
|
W,
|
|
WX,
|
|
R,
|
|
RX,
|
|
RW,
|
|
RWX
|
|
};
|
|
struct MMAP {
|
|
char magic[4];
|
|
uint32_t version;
|
|
uint32_t length;
|
|
}__attribute__((packed));
|
|
union MMAPTag {
|
|
struct {
|
|
uint8_t id;
|
|
uint8_t size;
|
|
}__attribute__((packed));
|
|
struct {
|
|
uint8_t id;
|
|
uint8_t size;
|
|
DEVICETYPE value;
|
|
}__attribute__((packed)) DEVICETYPE;
|
|
struct {
|
|
uint8_t id;
|
|
uint8_t size;
|
|
char value[1];
|
|
}__attribute__((packed)) DEVICENAME;
|
|
struct {
|
|
uint8_t id;
|
|
uint8_t size;
|
|
CPUARCH value;
|
|
}__attribute__((packed)) CPUARCH;
|
|
struct {
|
|
uint8_t id;
|
|
uint8_t size;
|
|
ENDIAN endian;
|
|
}__attribute__((packed)) ENDIAN;
|
|
struct {
|
|
uint8_t id;
|
|
uint8_t size;
|
|
uint8_t value;
|
|
}__attribute__((packed)) BITS;
|
|
struct {
|
|
uint8_t id;
|
|
uint8_t size;
|
|
phys_t start;
|
|
phys_t end;
|
|
PERM permission;
|
|
}__attribute__((packed)) REGION;
|
|
};
|
|
extern uint8_t mmap;
|
|
|
|
PMM_MMAP::PMM_MMAP(): PMM(0x1000) {
|
|
MMAP &header = *((MMAP*)&mmap);
|
|
if((header.magic[0] != 'M')||(header.magic[1] != 'M')||(header.magic[2] != 'A')||(header.magic[3] != 'P'))
|
|
for(;;); //This is not a mmap
|
|
#ifdef __BIG_ENDIAN__
|
|
header.length = __builtin_bswap32(header.length);
|
|
#endif
|
|
uint8_t *off=(uint8_t*)(&header+1);
|
|
for(uint32_t i=0;i<header.length;i++) {
|
|
MMAPTag &tag = *((MMAPTag*)off);
|
|
off+=tag.size;
|
|
switch(tag.id) {
|
|
case 0:
|
|
case 1:
|
|
case 5:
|
|
break; //Ignored for now
|
|
case 2: //CPUARCH
|
|
if(tag.CPUARCH.value !=
|
|
#ifdef __i386__
|
|
CPUARCH::X86
|
|
#else
|
|
#ifdef __x86_64__
|
|
CPUARCH::X86_64
|
|
#else
|
|
CPUARCH::ARM
|
|
#endif
|
|
#endif
|
|
)
|
|
for(;;);
|
|
break;
|
|
case 3:
|
|
hostEndian = tag.ENDIAN.endian ==
|
|
#ifdef __BIG_ENDIAN__
|
|
ENDIAN::BIG
|
|
#else
|
|
ENDIAN::LITTLE
|
|
#endif
|
|
;
|
|
break;
|
|
case 4:
|
|
bits = tag.BITS.value;
|
|
break;
|
|
default:
|
|
for(;;);
|
|
}
|
|
}
|
|
}
|
|
PMM_MMAP::~PMM_MMAP() {}
|
|
auto PMM_MMAP::isFree(phys_t addr) -> bool {
|
|
MMAP &header = *((MMAP*)&mmap);
|
|
uint8_t *off=(uint8_t*)(&header+1);
|
|
for(uint32_t i=0;i<header.length;i++) {
|
|
MMAPTag &tag = *((MMAPTag*)off);
|
|
off+=tag.size;
|
|
if(tag.id != 5)
|
|
continue;
|
|
if((tag.REGION.start > addr) || (tag.REGION.end < addr))
|
|
continue;
|
|
if(tag.REGION.permission == PERM::RWX)
|
|
return PMM::isFree(addr);
|
|
}
|
|
return false;
|
|
}
|