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What existing OS? You stated, "when i jump from my bootloader to the c code". If you are booting your kernel on a live machine, then your kernel becomes the OS. If this has taken place, then you can certainly access that memory, but you probably need to map it first.aloktiagi wrote:Hi,
So how do i find out the I/O base address of a device when i jump from my bootloader to the c code without the OS being there i.e no lspci command!!!
Regards
Alok
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// RTL 8139 network card
if ((pciDev_Array[number].deviceID == 0x8139))
{
install_RTL8139(number);
}
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BaseAddressRTL8139_MMIO = (uint32_t) paging_acquire_pcimem(BaseAddressRTL8139_MMIO);
printf("BaseAddressRTL8139_MMIO mapped to virtual address %X\n", BaseAddressRTL8139_MMIO);
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void* paging_acquire_pcimem(uint32_t phys_addr)
{
static uint8_t* virt = PCI_MEM_START;
if (virt == PCI_MEM_END)
panic_assert(__FILE__, __LINE__, "Not enough PCI-memory available");
uint32_t pagenr = (uint32_t)virt/PAGESIZE;
// Check the page table and setup the page
ASSERT(kernel_pd->tables[pagenr/1024]);
kernel_pd->tables[pagenr/1024]->pages[pagenr%1024] = phys_addr | MEM_PRESENT | MEM_WRITE | MEM_KERNEL;
uint8_t* ret = virt;
virt += PAGESIZE;
return ret;
}
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irq_install_handler(32 + pciDev_Array[number].irq, rtl8139_handler);
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printf("\nMAC Receiver: ");
for (int8_t i = 4; i < 10; i++)
{
printf("%y ", network_buffer[i]);
}
printf("MAC Transmitter: ");
for (int8_t i = 10; i < 16; i++)
{
printf("%y ", network_buffer[i]);
}
Perhaps posting the exact error message might help. A seg fault as an OS detail, you shouldnt be getting a seg fault if you have used the above code in your OS.aloktiagi wrote:But i'm getting a seg fault. Any idea why?
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bar0 = pci_config_read1(0x04,0x00,0x00,0x10);
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int pci_config_read1(int bus, int device, int func, int content)
{
int idx,tmp;
idx = 0x80000000 + ((bus&0xFF)<<16) + ((device&0x1F)<<11) + ((func&0x7)<<8) + (content&0xFC);
outb(0xCF8,idx);
tmp = inb(0xCFC);
return tmp;
}
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void outb(u16int port, u8int value)
{
asm volatile ("outb %1, %0" : : "dN" (port), "a" (value));
}
u8int inb(u16int port)
{
u8int ret;
asm volatile("inb %1, %0" : "=a" (ret) : "dN" (port));
return ret;
}
Nope. You need to write and read a whole unsigned integer (that's 32bits, should be u32int in your code) and the 32bit functions (inl, outl). Hint: your idx is 0x80000000 plus something else; that obviously doesn't fit into a bytealoktiagi wrote:Hi
My function call is like this (bus and device are hard coded!)
functions is:Code: Select all
bar0 = pci_config_read1(0x04,0x00,0x00,0x10);
inb and outb look like thisCode: Select all
int pci_config_read1(int bus, int device, int func, int content) { int idx,tmp; idx = 0x80000000 + ((bus&0xFF)<<16) + ((device&0x1F)<<11) + ((func&0x7)<<8) + (content&0xFC); outb(0xCF8,idx); tmp = inb(0xCFC); return tmp; }
Previously i was using inl and outl instead of inb and outb in the function. Now i get the bar0 value as E4. This should be correct now? Thanks!!Code: Select all
void outb(u16int port, u8int value) { asm volatile ("outb %1, %0" : : "dN" (port), "a" (value)); } u8int inb(u16int port) { u8int ret; asm volatile("inb %1, %0" : "=a" (ret) : "dN" (port)); return ret; }
.So i switched to inb and outb and got E4 as BAR0 address!!!Fine that you receive these two byte data vendorID deviceID
What about the other data with one byte?
classID
subclassID
interfaceID
revID
irq
Do you get them correctly?
bars is length 4 bytes and offset 0x10, 0x14, ...
Perhaps you read only one or two byte of them
First, 0xe4 is at the start of the memory (it's the 228th byte actually). So, no way your bar is 0xe4. Second, can you post your inl and outl? I think they are brokenaloktiagi wrote:Hi
Yes true it shud be 32 bit and inl and outl need to be used but when i had used them the result of my BAR0 was empty.
Then ehenkes in his post told that
So i switched to inb and outb and got E4 as BAR0 address!!!Fine that you receive these two byte data vendorID deviceID
What about the other data with one byte?
classID
subclassID
interfaceID
revID
irq
Do you get them correctly?
bars is length 4 bytes and offset 0x10, 0x14, ...
Perhaps you read only one or two byte of them
.Code: Select all
int inportl(int port)
{
int ret_val;
__asm__ volatile ("in %%dx,%%eax" : "=a" (ret_val) : "d"(port));
return ret_val;
}
void outportl(int port, int val)
{
__asm__ volatile ("outl %%eax,%%dx" : : "a"(val), "d"(port));
}