Generic options for startup programs (QNX Neutrino)
All QNX Neutrino startup programs support the generic options described below.
There are additional options for the following architectures:
There are currently no additional options for MIPS or SH.
 |
Individual startup programs can override these options and may support
additional board-specific options.
The order of precedence is as follows:
- board-specific options
- architecture-specific options
- generic options
|
- -A
- Reboot the system on any abnormal termination of the kernel.
The default is to display information about the crash, and then halt.
- -D channel[.channel_opts]
- Specify an output channel for debugging information.
The format of this option and the default value vary from board to board.
- -F [~]value
- Control the flags field in the cpuinfo section of
the system page:
- value — OR the flags field with
value
- ~value — AND the flags field with
~value
For more information about the flags, see
“Structure of the system page”
in the Customizing Image Startup Programs chapter of the
Building Embedded Systems guide.
- -f [cpu_freq][,[cycles_freq][,timer_freq]]
- Specify CPU frequencies.
All frequencies can be followed by H for hertz,
K for kilohertz, or M for megahertz
(these suffixes aren't case-sensitive). If no
suffix is given, the library assumes megahertz if the
number is less than 1000; otherwise it assumes hertz.
If they're specified, cpu_freq, cycles_freq, and
timer_freq are used to set the corresponding variables
in the startup code:
- cpu_freq — the CPU clock frequency. It's also used
to set the speed field in the cpuinfo section of the
system page.
- cycles_freq — the frequency at which the
value returned by
ClockCycles() increments. It's also used to set the
cycles_per_sec field in the qtime
section of the system page.
- timer_freq — the frequency at which the timer chip
input runs. It's also used to set the timer_rate and
timer_scale values of the qtime section of the
system page.
If a variable is zero when it comes time to set the field(s)
on the system page, the library code attempts to deduce the proper
value by using one of the other frequency variables. Which one it uses
depends on the particular CPU and hardware.
- -I flag
- Enable kernel restoration as part of IFS restoration.
The flag is 0 to disable checksum verification, or 1 to enable it.
If checksum verification is enabled and fails, the entire image is reloaded.
|
Even if the IFS checksum verification is disabled, a checksum is still
performed
on the IFS Restoration internal data structure (approximately 32 bytes) to
ensure at least some data integrity.
|
For more information, see
Reloadable Image Filesystems
in the QNX Neutrino technotes.
- -i ifs2_size[,flags][,paddr_src][,paddr_dst]
- Enable secondary IFS restoration.
The arguments are:
- ifs2_size
- The size of the secondary IFS (note: this can be larger than the
actual size).
- flags
-
- Not specified — load the secondary IFS but don't try
to restore on wake-up
- R — load the secondary IFS and restore
- K or RK — load the secondary IFS and
restore with a checksum
- paddr_src
-
- Not specified — the secondary IFS is located in flash after
the primary IFS
- Specified — the secondary IFS is located at the physical
address specified
- paddr_dst
-
- Not specified — the secondary IFS will be copied to a
default location in RAM
- Specified — the secondary IFS will be copied to the
physical address specified
(choose an address in a “safe” place, such as at the end of
RAM away from where the primary image is copied)
If the checksum is enabled and fails, the entire secondary IFS is reloaded.
|
Even if the secondary IFS checksum is disabled, a checksum is still
performed on the IFS Restoration internal data structure (approximately
16 bytes) to ensure at least some data integrity.
|
For more information, see
Reloadable Image Filesystems
in the QNX Neutrino technotes.
- -j addr
- For use with JTAG/hardware debuggers.
Reserve 4 bytes of RAM at the physical address
specified by addr, and copy the physical address
of the location of the system page to addr
in RAM so that it can be retrieved by a hardware debugger.
- -K channel[.channel_opts]
- Specify an output channel for kernel debugger information.
The format of this option and the default value vary from board to board.
- -N hostname
- Specify the node name. The default is the local host.
- -P max_CPUs
- Specify the maximum number of processors to activate in a multicore
system.
This is useful for testing how well your application runs
on a system with fewer CPUs.
This option requires
procnto-smp
instead of procnto to have an effect.
- -R size[,align]
- Remove size memory from system use, optionally specifying
the alignment.
This is useful for testing in a restricted-memory environment.
The size and and alignment are in bytes, unless followed by one of
K (kilobytes), M (megabytes), or G
(gigabytes).
- -r addr,size[,flag]
- Remove size memory from system use starting at addr.
The flag is an optional
argument used to specify if the memory should be cleared:
| Flag:
|
Memory:
|
| None
|
Clears to 0
|
| 0
|
Clears to 0
|
| 1
|
Does not clear
|
- -S [~]section
- Turn on (or, if you use ~section, off) output
of the specified syspage section's information.
Use this to restrict the amount of syspage information.
For more information, see the description of
print_syspage()
in the Customizing Image Startup Programs chapter of
Building Embedded Systems.
- -T
- Prevent the startup program from setting the
SYSPAGE_ENTRY(qtime)->boot_time field.
If this field is 0 the first time you call
ClockTime()
to change the time of day, the kernel sets it to the appropriate value.
This is useful if the RTC hardware isn't in UTC.
- -v[v]...
- Be verbose. More v characters cause even more verbosity.
The following options are supported in the startup programs for ARM targets:
- -w value
- Set the cache policy:
- -wb sets write-back, read-allocate (no write-allocate) caching
- -wa sets write-back, write-allocate caching
- -wt sets write-through caching
The actual behavior depends on the processor; not all processors implement
all 3 types of caching.
If the processor doesn't implement the requested option,
the default cache policy is used.
The supported cache policies are specified in the processor configuration
file, armv_chip_xxxx.c:
| This field:
|
Specifies PTE encodings for the:
|
| pte
|
Default cache policy
|
| pte_wb
|
Write-back (-wb) policy
|
| pte_wa
|
Write-allocate (-wa) policy
|
| pte_wt
|
Write-through (-wt) policy
|
The configuration must specify at least the default (pte) field.
Any unsupported policy should specify 0 in the appropriate field,
and if that policy is requested via the -w option, it's
ignored, and the default policy is used.
The following options are supported in the startup programs for PowerPC
targets:
- -E
- Save and restore the External Access Register (EAR) in the context
when switching threads.
The EAR is an optional register available on some PPC600 family chips.
If the chip supports it, it should be saved and restored,
but the instructions that reference it are seldom used.
Accordingly, it's left out of the thread context for performance
reasons, unless you specify the -E option.
- -x
- Enable extended addressing.
This lets you access physical addresses above 4 GB.
This option is supported for backward compatibility; XAE is enabled by
default if the chip supports it.
The following options are supported in the startup programs for x86 targets:
- -B
- By default, x86 startups use the
Advanced Control and Power Interface (ACPI)
table to determine the number of logical CPUs on hyperthreaded systems.
Use this option to avoid checking for ACPI in the case of buggy BIOSs;
if ACPI isn't present or you specify -B, the startup uses
the Intel Multiprocessor Specification to determine the number of CPUs.
- -x
- Enable extended addressing.
This lets you access physical addresses above 4 GB.
|
This option has an effect only if the CPU supports more than 32 address
lines.
On x86 CPUs, extended addressing is supported if the
X86_CPU_PAE bit is on in the
SYSPAGE_ENTRY(cpuinfo)->flags.
For more information, see
“Structure of the system page”
in the Customizing Image Startup Programs chapter of
Building Embedded Systems.
|
mkifs,
procnto,
startup-*
ClockTime(),
SYSPAGE_ENTRY()
in the QNX Neutrino Library Reference
Customizing Image Startup Programs in Building Embedded Systems
Reloadable Image Filesystems
in the QNX Neutrino technotes