BIU_NVRAM
ISP_WRITE(isp, BIU_NVRAM, BIU_NVRAM_SELECT);
ISP_WRITE(isp, BIU_NVRAM, BIU_NVRAM_SELECT|BIU_NVRAM_CLOCK);
ISP_WRITE(isp, BIU_NVRAM, bit);
junk = ISP_READ(isp, BIU_NVRAM); /* force PCI flush */
ISP_WRITE(isp, BIU_NVRAM, bit | BIU_NVRAM_CLOCK);
junk = ISP_READ(isp, BIU_NVRAM); /* force PCI flush */
ISP_WRITE(isp, BIU_NVRAM, bit);
junk = ISP_READ(isp, BIU_NVRAM); /* force PCI flush */
ISP_WRITE(isp, BIU_NVRAM, BIU_NVRAM_SELECT|BIU_NVRAM_CLOCK);
rv = ISP_READ(isp, BIU_NVRAM);
ISP_WRITE(isp, BIU_NVRAM, BIU_NVRAM_SELECT);
junk = ISP_READ(isp, BIU_NVRAM); /* force PCI flush */
ISP_WRITE(isp, BIU_NVRAM, 0);
junk = ISP_READ(isp, BIU_NVRAM); /* force PCI flush */