PCI will tell you if PCI-to-ISA bridge exist. If any then you should load ISA driver and test devices. PCI-to-ISA bridge may exist even if there isn't any ISA slots on your motherboard.Combuster wrote:The PCI space won't tell you all devices. ISA needs to be detected manually, standard peripherals must be detected manually. the floppy and ide controllers may not be listed in the PCI tables, nor in the ACPI tables, especially when dealing with computers predating those standards.
I currently have a hdd driver based on that tutorial, though I am not sure if it will work on my S-ATA drive. I also saw that this way of communicating to a drive only lets me access 4 drives, 2 on primary and 2 on secondary IDE.Use PIO, this a fairly good tutorial
Code: Select all
int DetectDrive(unsigned char ide, unsigned long drive)
{
unsigned short tmpword;
unsigned char check;
unsigned short base;
unsigned short buf[256];
unsigned short idx;
if (ide == 0)
base = 0x1F0;
else
if (ide == 1)
base = 0x170;
else
return 0; // only 2 IDE controllers
outb(base + 3, 0x88); // write
check = inb(base + 3); // read
if (check != 0x88) // check if the magic value is the same
{
puts("Error: the IDE controller does not exist.\n");
return 0;
}
outb(base + 6, 0xA0 | (drive << 4));
sleep(1); // wait a while, min wait time: 400ns
outb(base + 7, 0xEC); //send identify
if (!waituntilbusy(base))
return 0;
buf[0] = inw(base);
if (buf[0]) // if exists
{
puts("Drive exists\n");
for (idx = 1; idx < 256; idx++)
buf[idx] = inw(base); // read a word
if (buf[0] | 0x0040 == buf[0])
puts("Hard drive\n");
else
{
puts("No hard drive\n");
return 0;
}
return 1;
}
else
{
puts("Drive does not exist\n");
return 0;
}
}Thanks, I'll try and look up some documents.Scan the PCI Configuration Space
It's my understanding that all motherboards have a PCI-to-ISA bridge, as most legacy devices (e.g. floppy) are connected to the (internal) ISA bus. But I may be wrong.Masterkiller wrote:PCI-to-ISA bridge may exist even if there isn't any ISA slots on your motherboard.
Well, start with explaining how you detect it in Bochs.Revelation wrote:When I use my detect code outside Bochs, it doesn't detect my SATA drive. Should I do something special for that?
Code: Select all
static unsigned long pci_read(unsigned int bus,unsigned int dev,unsigned int func,unsigned int reg)
{
outl(0xCF8, ((unsigned long) 0x80000000 | (bus << 16) | (dev << 11) | (func << 8) | reg));
return inl(0xCFC);
}
void scanpci()
{
unsigned char bus, dev, func;
unsigned long a, value;
unsigned char classcode;
for (bus = 0; bus < 255; bus++)
for (dev = 0; dev < 32; dev++)
for (func = 0; func < 8; func++)
{
a = pci_read(bus, dev, func, 0x08); // class info
classcode = a >> 8;
if (classcode == 0x0C)
puts("USB detected\n");
}
}
Suggestion: It depends on the compiler, but mostly "int" type uses current section BITS size. For 16-bit DOS application it should be 16-bit, in 32-bit protected mode 32-bit and in long-mode 64-bit. The "long" type is strict 32-bit in size. You should use it instead of int.Revelation wrote:I'm probably doing something very stupid, but why doesn't this work?
Code: Select all
static unsigned long pci_read(unsigned int bus,unsigned int dev,unsigned int func,unsigned int reg) { outl(0xCF8, ((unsigned long) 0x80000000 | (bus << 16) | (dev << 11) | (func << 8) | reg)); return inl(0xCFC); } void scanpci() { unsigned char bus, dev, func; unsigned long a, value; unsigned char classcode; for (bus = 0; bus < 255; bus++) for (dev = 0; dev < 32; dev++) for (func = 0; func < 8; func++) { a = pci_read(bus, dev, func, 0x08); // class info classcode = a >> 8; if (classcode == 0x0C) puts("USB detected\n"); } }
'int' is guaranteed to be 32 bits on modern 32 and 64 bit platforms. However, instead of directly using long, it's better to define an int32_t type and use that for maximum portability.Masterkiller wrote:The "long" type is strict 32-bit in size. You should use it instead of int.