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void pci_scan() {

    printf("[INFO] Scanning PCI devices... \n");

    for (uint8_t bus = 0; bus < 256; bus++) {
        for (uint8_t device = 0; device < 32; device++) {
            for (uint8_t function = 0; function < 8; function++) {

                // read the device and  vendor id
                uint32_t _dev_vend = pci_read(bus, device, function, DEVICE_VENDOR_OFFSET);
                uint16_t device_id = _dev_vend >> 16;       // upper 16 bit
                uint16_t vendor_id = _dev_vend & 0xFFFF;    // lower 16 bit

                // if(bus == 0 & device == 31 & function == 2){
                //     printf("Device ID: %x, Vendor ID: %x\n", device_id, vendor_id);
                // }

                // Check if the device exists
                if (vendor_id == 0xFFFF) {
                    continue; // Invalid device
                }

                if(vendor_id == 0x8086 & device_id == 0x0) { // Intel do not have any pci device with device id 0x0
                    continue;
                }

                if(vendor_id == 0x1234 & device_id == 0x0) { // No vendor not have any pci device with device id 0x0
                    continue;
                }
                
                // Read the status and command
                uint32_t _status_command = pci_read(bus, device, function, STATUS_COMMAND_OFFSET);
                uint16_t status = _status_command >> 16;       // upper 16 bit
                uint16_t command = _status_command & 0xFFFF;   // lower 16 bit
                
                // Read the class and subclass codes
                uint32_t _class_code = pci_read(bus, device, function, CLASS_SUBCLASS_PROG_REV_OFFSET);
                uint8_t class = (_class_code >> 24) & 0xFF;     // upper 8 bit
                uint8_t subclass = (_class_code >> 16) & 0xFF;  // 23-16 th bit
                uint8_t prog_if = (_class_code >> 8) & 0xFF;    // 15-8 th bit
                uint8_t revision = (_class_code >> 0) & 0xFF;   // lower 8 bit

                // Read bist, header type, latency timer, cache line size
                uint32_t _bist = pci_read(bus, device, function, BIST_HEADER_LATENCY_CACHE_LINE_OFFSET);
                uint8_t bist = (_bist >> 24) & 0xFF;            // upper 8 bit
                uint8_t header_type = (_bist >> 16) & 0xFF;     // 23-16 th bit
                uint8_t latency_timer = (_bist >> 8) & 0xFF;    // 15-8 th bit
                uint8_t cache_line_size = (_bist >> 0) & 0xFF;  // lower 8 bit

                printf("Device ID: %x, Vendor ID: %x\n", device_id, vendor_id);

                // Detecting SATA Disk and storing into sata_disks array
                int found_sata = detect_sata_disk(bus, device, function,
                    class, subclass, prog_if, revision);
                if(found_sata) {
                    break;
                }

                // Detecting Network Controller
                int found_network = detect_network_controller(bus, device, function,
                    class, subclass, prog_if, revision);
                if(found_network){
                    break;
                }

                // Detecting Wireless controller
                int found_wireless = detect_wireless_controller(bus, device, function,
                    class, subclass, prog_if, revision);
                if(found_network){
                    break;
                }
            }
        }
    }
    printf("[INFO] PCI Scan Completed\n");
    printf("Total %d SATA drives found\n", total_sata_disks);
}

Code: Select all

for (uint32_t index = 0; index < (256 * 32 * 8); index++) {
        uint8_t bus = (index >> 8) & 0xFF;
        uint8_t device = (index >> 3) & 0x1F;
        uint8_t function = index & 0x07;
        
        . . .
        }