请教一个ata设备识别的奇怪问题

[jackydi]

VxWorks 6.9系统，P2020bsp，配置了si31xx的ata硬盘，挂在pcie上，硬盘设备为"/ata0:1"，之前使用的时候都是好用的，今天突然识别不出来"/ata0:1"，却出来一个“/cdrom0:0”的设备，不知道是怎么回事，为什么会识别为cdrom呢？
可以肯定是底板的问题，因为相同的硬盘和子卡换到其他底板上就正常，其他正常的子卡和硬盘换到这个底板上也不正常。现在想知道可能是哪里的问题，应该怎么查找呢？同一个底板上的两个卡位都是相同的问题。
我使用vxbPciHeaderShow 命令查看pci设备的寄存器也是相同的。
如下：

-> vxbPciHeaderShow 0x0034e750,1,0,0
vendor ID =                   0x1095
device ID =                   0x3132
command register =            0x0007
status register =             0x0010
revision ID =                 0x01
class code =                  0x01
sub class code =              0x80
programming interface =       0x00
cache line =                  0x08
latency time =                0x00
header type =                 0x00
BIST =                        0x00
base address 0 =              0xa4000004
base address 1 =              0x00000000
base address 2 =              0xa4004004
base address 3 =              0x00000000
base address 4 =              0xa8000001
base address 5 =              0x00000000
cardBus CIS pointer =         0x00000000
sub system vendor ID =        0x1095
sub system ID =               0x3132
expansion ROM base address =  0x00000000
interrupt line =              0x08
interrupt pin =               0x01
min Grant =                   0x00
max Latency =                 0x00
Capabilities - Power Management 
Capabilities - Message Signaled Interrupts: 0x5c control 0x80 Disabled, 64-bit, MME: 0 MMC: 0
        Address: 0000000000000000  Data: 0x0000
        Per-vector Mask: Unsupported 
Capabilities - PCIe: Legacy Endpoint, IRQ 0
        Device: Max Payload: 1024 bytes, Extended Tag: 5-bit
                Acceptable Latency: L0 - <64ns, L1 - <1us
                Errors Enabled: 
                Max Read Request 512 bytes
        Link: MAX Speed - 2.5Gb/s, MAX Width - by 1 Port - 0 ASPM - L0s
                Latency: L0s - >4us, L1 - >64us
                ASPM - Disabled, RCB - 64bytes
                Speed - 2.5Gb/s, Width - by 1
Ext Capabilities - Advanced Error Reporting. 0x100. Version 1. AER Control: 0xa0 
        Uncorrectable : Mask 0x0. Severity 0x62011 
        Uncorrectable Status: 
        Correctable : Mask 0x0. 
        Correctable Status: 
        HeaderLog: 
        Error Source Identification: 0x0 0x0 

value = 0 = 0x0