The HAL Port

Linker Scripts and Memory Maps

The platform HAL package provides the memory layout information needed to generate the linker script. The key memory locations are as follows:

Flash: This is located at address 0xFC000000 of the physical memory space. It is mapped by the BAR registers 1-1 to virtual address 0xFC000000 with caching enabled, and to 0x50000000 with caching disabled. The PowerPC reset vector is at 0xFFF00100 so RedBoot is normally programmed from 0xFFF00000.
SDRAM: This is located at address 0x00000000 of the physical memory space. The first 0x3000 bytes are used for the exception entry trampolines. The following 512 bytes contain the VSR table and the next 256 bytes are normally used for the eCos virtual vectors, allowing RAM-based applications to use services provided by the ROM monitor. For ROM and JTAG startup, all remaining SDRAM is available. For RAM startup, available RAM starts at location 0x00100000, with the bottom 1MiB reserved for use by RedBoot. The SDRAM is mapped 1-1 with cache enabled at virtual address 0x00000000 and uncached at 0x20000000.
SRAM: The 128KiB of on-chip SRAM is mapped 1-1 at 0x30000000. This memory is not used by eCos and is therefore available for application use.
Peripherals: All on-chip peripherals are accessed relative to the address in the IMMBAR register. Both the PEEDI configuration file and eCos itself set this to 0xE0000000. The CPLD is mapped to 0xE2000000 and is accessible just beyond the IMMBAR peripherals.

Real-time characterization

The tm_basic kernel test gives statistics gathered about the real-time characterization and performance of the kernel. The sample output is shown here for information.

            Startup, main stack : stack used  1032 size  5920
             Startup :  Interrupt stack used   571 size  4096
             Startup : Idlethread stack used   480 size  2048

eCos Kernel Timings
Notes: all times are in microseconds (.000001) unless otherwise stated

Reading the hardware clock takes 0 'ticks' overhead
... this value will be factored out of all other measurements
Clock interrupt took    1.49 microseconds (74 raw clock ticks)

Testing parameters:
   Clock samples:            32
   Threads:                  64
   Thread switches:         128
   Mutexes:                  32
   Mailboxes:                32
   Semaphores:               32
   Scheduler operations:    128
   Counters:                 32
   Flags:                    32
   Alarms:                   32


                                 Confidence
     Ave     Min     Max     Var  Ave  Min  Function
  ======  ======  ======  ====== ========== ========
    2.91    2.38    3.68    0.29   46%  32% Create thread
    0.28    0.26    1.00    0.02   98%  98% Yield thread [all suspended]
    0.29    0.26    0.98    0.04   90%  90% Suspend [suspended] thread
    0.27    0.26    0.62    0.01   96%  96% Resume thread
    0.40    0.38    1.10    0.03   96%  96% Set priority
    0.03    0.02    0.24    0.01   98%  73% Get priority
    0.72    0.68    1.90    0.06   84%  84% Kill [suspended] thread
    0.26    0.26    0.34    0.00   98%  98% Yield [no other] thread
    0.41    0.38    0.86    0.03   67%  85% Resume [suspended low prio] thread
    0.26    0.26    0.28    0.00   96%  96% Resume [runnable low prio] thread
    0.33    0.32    0.42    0.01   62%  35% Suspend [runnable] thread
    0.27    0.26    0.28    0.01   73%  73% Yield [only low prio] thread
    0.26    0.26    0.34    0.01   84%  84% Suspend [runnable->not runnable]
    0.69    0.68    0.84    0.02   90%  90% Kill [runnable] thread
    0.64    0.60    2.16    0.06   93%  93% Destroy [dead] thread
    1.14    1.10    1.44    0.05   79%  79% Destroy [runnable] thread
    3.93    2.88    5.30    0.38   54%   7% Resume [high priority] thread
    0.67    0.62    2.36    0.06   85%  75% Thread switch

    0.02    0.02    0.18    0.00   99%  99% Scheduler lock
    0.21    0.20    0.30    0.01   62%  62% Scheduler unlock [0 threads]
    0.21    0.20    0.22    0.01   61%  61% Scheduler unlock [1 suspended]
    0.21    0.20    0.30    0.01   68%  68% Scheduler unlock [many suspended]
    0.21    0.20    0.22    0.01   60%  60% Scheduler unlock [many low prio]

    0.18    0.04    0.80    0.11   43%  43% Init mutex
    0.37    0.34    1.28    0.06   96%  96% Lock [unlocked] mutex
    0.38    0.34    1.72    0.08   96%  96% Unlock [locked] mutex
    0.30    0.26    1.02    0.04   96%  96% Trylock [unlocked] mutex
    0.26    0.26    0.34    0.00   96%  96% Trylock [locked] mutex
    0.06    0.04    0.42    0.02   96%  96% Destroy mutex
    1.57    1.54    1.82    0.02   93%   3% Unlock/Lock mutex

    0.33    0.14    1.22    0.15   62%  50% Create mbox
    0.01    0.00    0.04    0.01   50%  46% Peek [empty] mbox
    0.36    0.32    1.44    0.07   96%  96% Put [first] mbox
    0.02    0.02    0.10    0.00   96%  96% Peek [1 msg] mbox
    0.35    0.32    0.46    0.04   71%  71% Put [second] mbox
    0.02    0.02    0.10    0.00   96%  96% Peek [2 msgs] mbox
    0.34    0.30    1.28    0.06   96%  96% Get [first] mbox
    0.31    0.30    0.40    0.01   50%  46% Get [second] mbox
    0.29    0.26    0.92    0.04   96%  96% Tryput [first] mbox
    0.31    0.28    0.86    0.03   96%  96% Peek item [non-empty] mbox
    0.34    0.32    0.80    0.03   96%  96% Tryget [non-empty] mbox
    0.27    0.26    0.34    0.01   96%  59% Peek item [empty] mbox
    0.27    0.26    0.36    0.01   96%  50% Tryget [empty] mbox
    0.03    0.02    0.12    0.01   71%  71% Waiting to get mbox
    0.03    0.02    0.12    0.01   71%  71% Waiting to put mbox
    0.08    0.06    0.50    0.03   96%  96% Delete mbox
    1.17    1.16    1.34    0.01   96%  96% Put/Get mbox

    0.07    0.04    0.26    0.04   75%  75% Init semaphore
    0.26    0.26    0.34    0.01   93%  93% Post [0] semaphore
    0.33    0.32    0.42    0.01   50%  46% Wait [1] semaphore
    0.27    0.24    0.74    0.03   96%  96% Trywait [0] semaphore
    0.25    0.24    0.36    0.01   96%  65% Trywait [1] semaphore
    0.05    0.04    0.22    0.02   96%  62% Peek semaphore
    0.06    0.04    0.32    0.02   50%  46% Destroy semaphore
    1.09    1.08    1.20    0.01   96%  62% Post/Wait semaphore

    0.21    0.06    0.66    0.08   50%  25% Create counter
    0.03    0.02    0.20    0.02   96%  75% Get counter value
    0.02    0.02    0.10    0.00   96%  96% Set counter value
    0.31    0.30    0.56    0.02   96%  93% Tick counter
    0.06    0.04    0.32    0.02   59%  37% Delete counter

    0.08    0.04    0.54    0.06   93%  71% Init flag
    0.30    0.26    1.00    0.04   96%  96% Destroy flag
    0.26    0.24    0.90    0.04   96%  96% Mask bits in flag
    0.30    0.28    0.88    0.04   96%  96% Set bits in flag [no waiters]
    0.41    0.36    1.42    0.06   96%  96% Wait for flag [AND]
    0.35    0.34    0.44    0.01   96%  50% Wait for flag [OR]
    0.38    0.36    0.38    0.00   96%   3% Wait for flag [AND/CLR]
    0.35    0.34    0.46    0.01   96%  50% Wait for flag [OR/CLR]
    0.02    0.02    0.12    0.01   96%  96% Peek on flag

    0.34    0.18    1.14    0.08   71%  21% Create alarm
    0.41    0.38    1.18    0.05   96%  96% Initialize alarm
    0.25    0.24    0.42    0.02   96%  62% Disable alarm
    0.39    0.36    0.88    0.03   96%  96% Enable alarm
    0.30    0.28    0.46    0.02   96%  50% Delete alarm
    0.35    0.34    0.42    0.01   96%  59% Tick counter [1 alarm]
    2.13    2.12    2.14    0.01   53%  53% Tick counter [many alarms]
    0.57    0.56    0.68    0.01   96%  59% Tick & fire counter [1 alarm]
    9.50    9.50    9.58    0.00   96%  96% Tick & fire counters [>1 together]
    2.36    2.36    2.36    0.00  100% 100% Tick & fire counters [>1 separately]
    1.18    1.18    1.32    0.00   99%  99% Alarm latency [0 threads]
    1.45    1.18    1.72    0.16   51%  27% Alarm latency [2 threads]
    4.51    3.24    6.08    0.56   50%  21% Alarm latency [many threads]
    2.11    2.10    3.44    0.02   99%  99% Alarm -> thread resume latency

    0.57    0.32    2.36    0.00            Clock/interrupt latency

    0.75    0.38    2.88    0.00            Clock DSR latency

   18      0    1177  (main stack:  1272)  Thread stack used (1960 total)
           All done, main stack : stack used  1272 size  5920
            All done :  Interrupt stack used   263 size  4096
            All done : Idlethread stack used  1117 size  2048

Timing complete - 29950 ms total

PASS:<Basic timing OK>
EXIT:<done>

The HAL Port

Name

Overview

Startup

Linker Scripts and Memory Maps

Real-time characterization

Other Issues