Initial kernel command string (Was: Generating elf kernel ?)

Fri Sep 17 19:46:27 EST 2010

Guillaume Dargaud wrote:
> Thanks for helping about the elf issue, I got it running. The problem was that 
> I wasn't using the proper file produced by make !
> 
> 
> Now I have a strange and probably simple problem that the Initial kernel 
> command string is incorrect. I want, and I have set in the .config:
> CONFIG_CMDLINE="console=ttyUL0,115200 rw root=/dev/nfs ip=bootp"

I think you should modify the bootargs on your dts.
------
        chosen {
                bootargs = "console=ttyS0 root=/dev/ram";
                linux,stdout-path = "/plb at 0/serial at 83e00000";
        } ;

> 
> But when my kernel boots it uses:
> console=ttyUL0 root=/dev/ram
> 
> I can check:
> strings arch/powerpc/boot/simpleImage.virtex405-ml405.elf | grep console
> Vconsole=ttyUL0 root=/dev/ram
> 
> 
> Also my previous kernel would wait for 2 seconds at the beginning to allow me 
> to change the initial command string via the serial port, but now it just runs 
> right through. How can I enable this option ?

It's possible on PowerPC kernel :)

You can take a look at the file, arch/powerpc/boot/main.c.
------
static void prep_cmdline(void *chosen)
{
        if (cmdline[0] == '\0')
                getprop(chosen, "bootargs", cmdline, COMMAND_LINE_SIZE-1);

        printf("\n\rLinux/PowerPC load: %s", cmdline);
        /* If possible, edit the command line */
        if (console_ops.edit_cmdline)
                console_ops.edit_cmdline(cmdline, COMMAND_LINE_SIZE);
        printf("\n\r");
.......

So you have to define one function, console_ops.edit_cmdline -->
serial_edit_cmdline. Or you can try bind this to your boot console ops directly.
Please refer to the file, arch/powerpc/boot/serial.c.

Cheers!
Tiejun

> 
> On the plus side it boots in .5 seconds !
> 
> Here's my .config:
> CONFIG_40x=y
> CONFIG_4xx=y
> CONFIG_PPC_MMU_NOHASH=y
> CONFIG_PPC_MMU_NOHASH_32=y
> CONFIG_NOT_COHERENT_CACHE=y
> CONFIG_PPC32=y
> CONFIG_WORD_SIZE=32
> CONFIG_MMU=y
> CONFIG_GENERIC_CMOS_UPDATE=y
> CONFIG_GENERIC_TIME=y
> CONFIG_GENERIC_TIME_VSYSCALL=y
> CONFIG_GENERIC_CLOCKEVENTS=y
> CONFIG_GENERIC_HARDIRQS=y
> CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ=y
> CONFIG_IRQ_PER_CPU=y
> CONFIG_NR_IRQS=512
> CONFIG_STACKTRACE_SUPPORT=y
> CONFIG_HAVE_LATENCYTOP_SUPPORT=y
> CONFIG_TRACE_IRQFLAGS_SUPPORT=y
> CONFIG_LOCKDEP_SUPPORT=y
> CONFIG_RWSEM_XCHGADD_ALGORITHM=y
> CONFIG_ARCH_HAS_ILOG2_U32=y
> CONFIG_GENERIC_HWEIGHT=y
> CONFIG_GENERIC_FIND_NEXT_BIT=y
> CONFIG_GENERIC_GPIO=y
> CONFIG_PPC=y
> CONFIG_EARLY_PRINTK=y
> CONFIG_GENERIC_NVRAM=y
> CONFIG_SCHED_OMIT_FRAME_POINTER=y
> CONFIG_ARCH_MAY_HAVE_PC_FDC=y
> CONFIG_PPC_OF=y
> CONFIG_OF=y
> CONFIG_PPC_UDBG_16550=y
> CONFIG_AUDIT_ARCH=y
> CONFIG_GENERIC_BUG=y
> CONFIG_DTC=y
> CONFIG_DEFAULT_UIMAGE=y
> CONFIG_ARCH_HIBERNATION_POSSIBLE=y
> CONFIG_PPC_DCR_NATIVE=y
> CONFIG_PPC_DCR_MMIO=y
> CONFIG_PPC_DCR=y
> CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC=y
> CONFIG_PPC_ADV_DEBUG_REGS=y
> CONFIG_PPC_ADV_DEBUG_IACS=2
> CONFIG_PPC_ADV_DEBUG_DACS=2
> CONFIG_PPC_ADV_DEBUG_DVCS=0
> CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config"
> CONFIG_CONSTRUCTORS=y
> CONFIG_EXPERIMENTAL=y
> CONFIG_BROKEN_ON_SMP=y
> CONFIG_INIT_ENV_ARG_LIMIT=32
> CONFIG_LOCALVERSION=""
> CONFIG_TREE_RCU=y
> CONFIG_RCU_FANOUT=32
> CONFIG_IKCONFIG=y
> CONFIG_IKCONFIG_PROC=y
> CONFIG_LOG_BUF_SHIFT=14
> CONFIG_NAMESPACES=y
> CONFIG_CC_OPTIMIZE_FOR_SIZE=y
> CONFIG_SYSCTL=y
> CONFIG_ANON_INODES=y
> CONFIG_SYSCTL_SYSCALL=y
> CONFIG_KALLSYMS=y
> CONFIG_HOTPLUG=y
> CONFIG_PRINTK=y
> CONFIG_BUG=y
> CONFIG_ELF_CORE=y
> CONFIG_BASE_FULL=y
> CONFIG_FUTEX=y
> CONFIG_EPOLL=y
> CONFIG_SIGNALFD=y
> CONFIG_TIMERFD=y
> CONFIG_EVENTFD=y
> CONFIG_SHMEM=y
> CONFIG_AIO=y
> CONFIG_HAVE_PERF_EVENTS=y
> CONFIG_PERF_EVENTS=y
> CONFIG_VM_EVENT_COUNTERS=y
> CONFIG_COMPAT_BRK=y
> CONFIG_SLAB=y
> CONFIG_HAVE_OPROFILE=y
> CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y
> CONFIG_HAVE_IOREMAP_PROT=y
> CONFIG_HAVE_KPROBES=y
> CONFIG_HAVE_KRETPROBES=y
> CONFIG_HAVE_ARCH_TRACEHOOK=y
> CONFIG_HAVE_DMA_ATTRS=y
> CONFIG_HAVE_DMA_API_DEBUG=y
> CONFIG_SLABINFO=y
> CONFIG_RT_MUTEXES=y
> CONFIG_BASE_SMALL=0
> CONFIG_MODULES=y
> CONFIG_MODULE_UNLOAD=y
> CONFIG_MODULE_FORCE_UNLOAD=y
> CONFIG_BLOCK=y
> CONFIG_IOSCHED_NOOP=y
> CONFIG_IOSCHED_DEADLINE=y
> CONFIG_IOSCHED_CFQ=y
> CONFIG_DEFAULT_CFQ=y
> CONFIG_DEFAULT_IOSCHED="cfq"
> CONFIG_INLINE_SPIN_UNLOCK=y
> CONFIG_INLINE_SPIN_UNLOCK_IRQ=y
> CONFIG_INLINE_READ_UNLOCK=y
> CONFIG_INLINE_READ_UNLOCK_IRQ=y
> CONFIG_INLINE_WRITE_UNLOCK=y
> CONFIG_INLINE_WRITE_UNLOCK_IRQ=y
> CONFIG_PPC4xx_GPIO=y
> CONFIG_XILINX_VIRTEX=y
> CONFIG_XILINX_VIRTEX_GENERIC_BOARD=y
> CONFIG_PPC40x_SIMPLE=y
> CONFIG_XILINX_VIRTEX_II_PRO=y
> CONFIG_XILINX_VIRTEX_4_FX=y
> CONFIG_IBM405_ERR77=y
> CONFIG_IBM405_ERR51=y
> CONFIG_SIMPLE_GPIO=y
> CONFIG_GENERIC_CLOCKEVENTS_BUILD=y
> CONFIG_HZ_250=y
> CONFIG_HZ=250
> CONFIG_PREEMPT_VOLUNTARY=y
> CONFIG_BINFMT_ELF=y
> CONFIG_ARCH_ENABLE_MEMORY_HOTPLUG=y
> CONFIG_ARCH_HAS_WALK_MEMORY=y
> CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE=y
> CONFIG_SPARSE_IRQ=y
> CONFIG_MAX_ACTIVE_REGIONS=32
> CONFIG_ARCH_FLATMEM_ENABLE=y
> CONFIG_ARCH_POPULATES_NODE_MAP=y
> CONFIG_SELECT_MEMORY_MODEL=y
> CONFIG_FLATMEM_MANUAL=y
> CONFIG_FLATMEM=y
> CONFIG_FLAT_NODE_MEM_MAP=y
> CONFIG_PAGEFLAGS_EXTENDED=y
> CONFIG_SPLIT_PTLOCK_CPUS=4
> CONFIG_ZONE_DMA_FLAG=1
> CONFIG_BOUNCE=y
> CONFIG_VIRT_TO_BUS=y
> CONFIG_DEFAULT_MMAP_MIN_ADDR=4096
> CONFIG_PPC_4K_PAGES=y
> CONFIG_FORCE_MAX_ZONEORDER=11
> CONFIG_PROC_DEVICETREE=y
> CONFIG_CMDLINE_BOOL=y
> CONFIG_CMDLINE="console=ttyUL0,115200 rw root=/dev/nfs ip=bootp"
> CONFIG_EXTRA_TARGETS=""
> CONFIG_ISA_DMA_API=y
> CONFIG_ZONE_DMA=y
> CONFIG_NEED_DMA_MAP_STATE=y
> CONFIG_4xx_SOC=y
> CONFIG_PPC_PCI_CHOICE=y
> CONFIG_ADVANCED_OPTIONS=y
> CONFIG_LOWMEM_SIZE=0x30000000
> CONFIG_PAGE_OFFSET=0xc0000000
> CONFIG_KERNEL_START=0xc0000000
> CONFIG_PHYSICAL_START=0x00000000
> CONFIG_TASK_SIZE=0xc0000000
> CONFIG_CONSISTENT_SIZE=0x00200000
> CONFIG_NET=y
> CONFIG_PACKET=y
> CONFIG_UNIX=y
> CONFIG_INET=y
> CONFIG_IP_FIB_HASH=y
> CONFIG_IP_PNP=y
> CONFIG_IP_PNP_DHCP=y
> CONFIG_IP_PNP_BOOTP=y
> CONFIG_INET_DIAG=y
> CONFIG_INET_TCP_DIAG=y
> CONFIG_TCP_CONG_CUBIC=y
> CONFIG_DEFAULT_TCP_CONG="cubic"
> CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
> CONFIG_STANDALONE=y
> CONFIG_PREVENT_FIRMWARE_BUILD=y
> CONFIG_FW_LOADER=y
> CONFIG_FIRMWARE_IN_KERNEL=y
> CONFIG_EXTRA_FIRMWARE=""
> CONFIG_OF_FLATTREE=y
> CONFIG_OF_DYNAMIC=y
> CONFIG_OF_DEVICE=y
> CONFIG_OF_GPIO=y
> CONFIG_XILINX_DRIVERS=y
> CONFIG_NEED_XILINX_LLDMA=y
> CONFIG_HAVE_IDE=y
> CONFIG_SCSI_MOD=y
> CONFIG_NETDEVICES=y
> CONFIG_NETDEV_1000=y
> CONFIG_XILINX_LLTEMAC=y
> CONFIG_XILINX_LLTEMAC_MARVELL_88E1111_GMII=y
> CONFIG_INPUT=y
> CONFIG_INPUT_MOUSEDEV=y
> CONFIG_INPUT_MOUSEDEV_SCREEN_X=1024
> CONFIG_INPUT_MOUSEDEV_SCREEN_Y=768
> CONFIG_SERIO=y
> CONFIG_SERIO_SERPORT=y
> CONFIG_VT=y
> CONFIG_CONSOLE_TRANSLATIONS=y
> CONFIG_VT_CONSOLE=y
> CONFIG_HW_CONSOLE=y
> CONFIG_DEVKMEM=y
> CONFIG_SERIAL_UARTLITE=y
> CONFIG_SERIAL_UARTLITE_CONSOLE=y
> CONFIG_SERIAL_CORE=y
> CONFIG_SERIAL_CORE_CONSOLE=y
> CONFIG_UNIX98_PTYS=y
> CONFIG_ARCH_WANT_OPTIONAL_GPIOLIB=y
> CONFIG_ARCH_REQUIRE_GPIOLIB=y
> CONFIG_GPIOLIB=y
> CONFIG_GPIO_SYSFS=y
> CONFIG_GPIO_XILINX=y
> CONFIG_SSB_POSSIBLE=y
> CONFIG_DUMMY_CONSOLE=y
> CONFIG_XILINX_EDK=y
> CONFIG_UIO=y
> CONFIG_UIO_PDRV=y
> CONFIG_UIO_PDRV_GENIRQ=y
> CONFIG_FILE_LOCKING=y
> CONFIG_PROC_FS=y
> CONFIG_PROC_SYSCTL=y
> CONFIG_PROC_PAGE_MONITOR=y
> CONFIG_SYSFS=y
> CONFIG_CONFIGFS_FS=y
> CONFIG_NETWORK_FILESYSTEMS=y
> CONFIG_NFS_FS=y
> CONFIG_NFS_V3=y
> CONFIG_ROOT_NFS=y
> CONFIG_LOCKD=y
> CONFIG_LOCKD_V4=y
> CONFIG_NFS_COMMON=y
> CONFIG_SUNRPC=y
> CONFIG_MSDOS_PARTITION=y
> CONFIG_BITREVERSE=y
> CONFIG_GENERIC_FIND_LAST_BIT=y
> CONFIG_CRC_CCITT=y
> CONFIG_CRC32=y
> CONFIG_HAS_IOMEM=y
> CONFIG_HAS_IOPORT=y
> CONFIG_HAS_DMA=y
> CONFIG_HAVE_LMB=y
> CONFIG_NLATTR=y
> CONFIG_GENERIC_ATOMIC64=y
> CONFIG_PRINTK_TIME=y
> CONFIG_ENABLE_WARN_DEPRECATED=y
> CONFIG_ENABLE_MUST_CHECK=y
> CONFIG_FRAME_WARN=1024
> CONFIG_DEBUG_BUGVERBOSE=y
> CONFIG_DEBUG_MEMORY_INIT=y
> CONFIG_RCU_CPU_STALL_DETECTOR=y
> CONFIG_SYSCTL_SYSCALL_CHECK=y
> CONFIG_HAVE_FUNCTION_TRACER=y
> CONFIG_HAVE_FUNCTION_GRAPH_TRACER=y
> CONFIG_HAVE_DYNAMIC_FTRACE=y
> CONFIG_HAVE_FTRACE_MCOUNT_RECORD=y
> CONFIG_TRACING_SUPPORT=y
> CONFIG_HAVE_ARCH_KGDB=y
> CONFIG_PPC_WERROR=y
> CONFIG_PRINT_STACK_DEPTH=64
> CONFIG_DEFAULT_SECURITY_DAC=y
> CONFIG_DEFAULT_SECURITY=""
> CONFIG_CRYPTO=y
> CONFIG_CRYPTO_ALGAPI=y
> CONFIG_CRYPTO_ALGAPI2=y
> CONFIG_CRYPTO_RNG=y
> CONFIG_CRYPTO_RNG2=y
> CONFIG_CRYPTO_AES=y
> CONFIG_CRYPTO_ANSI_CPRNG=y
> 