Name

HAL Port — Implementation Details

Overview

This documentation explains how the eCos HAL specification has been mapped onto the MIMXRT1050-EVK board hardware, and should be read in conjunction with that specification. The MIMXRT1050-EVK platform HAL package complements the Cortex-M architectural HAL and the i.MX variant HAL. It provides functionality which is specific to the target board.

Startup

For SRAM and JTAG startup, the HAL will perform initialization, programming the various internal registers including the PLL, peripheral clocks and pin multiplexing. The details of the early hardware startup may be found in the src/samx70_ek_misc.c in both hal_system_init() and hal_platform_init().

Memory Map

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

Internal SRAM
This is located at address 0x20200000 of the memory space, and is 512KiB in size. The eCos VSR table occupies the bottom 768 bytes, with the virtual vector table starting at 0x20000300 and extending to 0x20000400. At the top of SRAM CYGNUM_HAL_COMMON_INTERRUPTS_STACK_SIZE bytes are reserved for the interrupt stack. The remainder of internal RAM is available for use by applications.
External SDRAM
This is located at address 0x800000000 of the memory space. This region is 32MiB in size. RAM applications are by default configured to run from this memory. This memory is only available after RedBoot has been loaded from a boot device, since it is initialized by the DCD that is part of the boot image.
On-Chip Peripherals
These are accessible at locations 0x40000000 and 0xE0000000 upwards. Descriptions of the contents can be found in the i.MX RT10XX User Manual.

Linker Scripts

The platform linker scripts define the following symbols:

hal_vsr_table
This defines the location of the VSR table. This is set to 0x20200000 for all startup types, and space for 192 entries is reserved.
hal_virtual_vector_table
This defines the location of the virtual vector table used to communicate between a ROM monitor and an eCos application. This is allocated right after the VSR table, at 0x20400300.
hal_interrupt_stack
This defines the location of the interrupt stack. For all startup types this is allocated to the top of internal SRAM.
hal_startup_stack
This defines the location of the startup stack. For all startup types it is initially allocated at the half-way point of the interrupt stack.

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. The test was built for JTAG startup on a MIMXRT1050-EVK board.

Example 303.1. MIMXRT1050-EVK Real-time characterization

Configured 
Testing parameters:
   Clock samples:            32
   Threads:                  25
   Thread switches:         128
   Mutexes:                1165
   Mailboxes:               340
   Semaphores:             2040
   Scheduler operations:    128
   Counters:                680
   Flags:                  1360
   Alarms:                  582
   Stack Size:             1088

             Startup, main thrd : stack used   356 size  2048
             Startup : Idlethread stack used    76 size  1280

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    7.84 microseconds (7 raw clock ticks)

Testing parameters:
   Clock samples:            32
   Threads:                  25
   Thread switches:         128
   Mutexes:                  32
   Mailboxes:                32
   Semaphores:               32
   Scheduler operations:    128
   Counters:                 32
   Flags:                    32
   Alarms:                   32
   Stack Size:             1088


                                 Confidence
     Ave     Min     Max     Var  Ave  Min  Function
  ======  ======  ======  ====== ========== ========
INFO:<Ctrl-C disabled until test completion>
    6.64    5.00    8.00    0.72   76%   8% Create thread
    1.44    1.00    2.00    0.49   56%  56% Yield thread [all suspended]
    1.56    1.00    2.00    0.49   56%  44% Suspend [suspended] thread
    1.36    1.00    2.00    0.46   64%  64% Resume thread
    2.04    2.00    3.00    0.08   96%  96% Set priority
    0.32    0.00    1.00    0.44   68%  68% Get priority
    3.20    3.00    5.00    0.34   84%  84% Kill [suspended] thread
    1.48    1.00    2.00    0.50   52%  52% Yield [no other] thread
    1.96    1.00    3.00    0.15   88%   8% Resume [suspended low prio] thread
    1.40    1.00    2.00    0.48   60%  60% Resume [runnable low prio] thread
    2.04    2.00    3.00    0.08   96%  96% Suspend [runnable] thread
    1.52    1.00    2.00    0.50   52%  48% Yield [only low prio] thread
    1.40    1.00    2.00    0.48   60%  60% Suspend [runnable->not runnable]
    3.16    3.00    5.00    0.28   88%  88% Kill [runnable] thread
    3.52    3.00    5.00    0.54   96%  52% Destroy [dead] thread
    7.52    7.00    8.00    0.50   52%  48% Destroy [runnable] thread
    6.80    6.00    9.00    0.51   60%  32% Resume [high priority] thread
    2.34    2.00    4.00    0.46   66%  66% Thread switch

    0.33    0.00    1.00    0.44   67%  67% Scheduler lock
    1.21    1.00    2.00    0.33   78%  78% Scheduler unlock [0 threads]
    1.26    1.00    2.00    0.38   74%  74% Scheduler unlock [1 suspended]
    1.24    1.00    2.00    0.37   75%  75% Scheduler unlock [many suspended]
    1.26    1.00    2.00    0.38   74%  74% Scheduler unlock [many low prio]

    0.50    0.00    1.00    0.50  100%  50% Init mutex
    1.81    1.00    3.00    0.36   75%  21% Lock [unlocked] mutex
    1.88    1.00    2.00    0.22   87%  12% Unlock [locked] mutex
    1.59    1.00    2.00    0.48   59%  40% Trylock [unlocked] mutex
    1.53    1.00    2.00    0.50   53%  46% Trylock [locked] mutex
    0.44    0.00    1.00    0.49   56%  56% Destroy mutex
   10.00   10.00   10.00    0.00  100% 100% Unlock/Lock mutex

    0.56    0.00    1.00    0.49   56%  43% Create mbox
    0.38    0.00    1.00    0.47   62%  62% Peek [empty] mbox
    1.81    1.00    2.00    0.31   81%  18% Put [first] mbox
    0.38    0.00    1.00    0.47   62%  62% Peek [1 msg] mbox
    1.69    1.00    3.00    0.47   62%  34% Put [second] mbox
    0.38    0.00    1.00    0.47   62%  62% Peek [2 msgs] mbox
    1.78    1.00    3.00    0.39   71%  25% Get [first] mbox
    1.72    1.00    2.00    0.40   71%  28% Get [second] mbox
    1.59    1.00    2.00    0.48   59%  40% Tryput [first] mbox
    1.53    1.00    2.00    0.50   53%  46% Peek item [non-empty] mbox
    1.56    1.00    2.00    0.49   56%  43% Tryget [non-empty] mbox
    1.38    1.00    2.00    0.47   62%  62% Peek item [empty] mbox
    1.50    1.00    2.00    0.50  100%  50% Tryget [empty] mbox
    0.47    0.00    1.00    0.50   53%  53% Waiting to get mbox
    0.50    0.00    1.00    0.50  100%  50% Waiting to put mbox
    0.53    0.00    1.00    0.50   53%  46% Delete mbox
    6.66    6.00    7.00    0.45   65%  34% Put/Get mbox

    0.50    0.00    1.00    0.50  100%  50% Init semaphore
    1.44    1.00    2.00    0.49   56%  56% Post [0] semaphore
    1.59    1.00    2.00    0.48   59%  40% Wait [1] semaphore
    1.34    1.00    2.00    0.45   65%  65% Trywait [0] semaphore
    1.38    1.00    2.00    0.47   62%  62% Trywait [1] semaphore
    0.44    0.00    1.00    0.49   56%  56% Peek semaphore
    0.44    0.00    1.00    0.49   56%  56% Destroy semaphore
    6.31    6.00    7.00    0.43   68%  68% Post/Wait semaphore

    0.75    0.00    1.00    0.38   75%  25% Create counter
    0.47    0.00    1.00    0.50   53%  53% Get counter value
    0.38    0.00    1.00    0.47   62%  62% Set counter value
    1.81    1.00    2.00    0.31   81%  18% Tick counter
    0.50    0.00    1.00    0.50  100%  50% Delete counter

    0.41    0.00    1.00    0.48   59%  59% Init flag
    1.47    1.00    3.00    0.53   56%  56% Destroy flag
    1.25    1.00    2.00    0.38   75%  75% Mask bits in flag
    1.53    1.00    2.00    0.50   53%  46% Set bits in flag [no waiters]
    1.91    1.00    3.00    0.23   84%  12% Wait for flag [AND]
    1.97    1.00    3.00    0.12   90%   6% Wait for flag [OR]
    1.91    1.00    3.00    0.23   84%  12% Wait for flag [AND/CLR]
    1.94    1.00    2.00    0.12   93%   6% Wait for flag [OR/CLR]
    0.34    0.00    1.00    0.45   65%  65% Peek on flag

    0.88    0.00    1.00    0.22   87%  12% Create alarm
    2.47    2.00    3.00    0.50   53%  53% Initialize alarm
    1.47    1.00    2.00    0.50   53%  53% Disable alarm
    2.38    2.00    3.00    0.47   62%  62% Enable alarm
    1.59    1.00    2.00    0.48   59%  40% Delete alarm
    1.84    1.00    2.00    0.26   84%  15% Tick counter [1 alarm]
    7.34    7.00    8.00    0.45   65%  65% Tick counter [many alarms]
    2.97    2.00    3.00    0.06   96%   3% Tick & fire counter [1 alarm]
   42.19   42.00   43.00    0.30   81%  81% Tick & fire counters [>1 together]
    8.47    8.00    9.00    0.50   53%  53% Tick & fire counters [>1 separately]
    7.00    7.00    7.00    0.00  100% 100% Alarm latency [0 threads]
    6.59    6.00    7.00    0.49   58%  41% Alarm latency [2 threads]
    6.67    6.00    7.00    0.44   67%  32% Alarm latency [many threads]
   11.02   11.00   13.00    0.03   99%  99% Alarm -> thread resume latency

    0.00    0.00    0.00    0.00            Clock/interrupt latency

    3.08    2.00    4.00    0.00            Clock DSR latency

     180     148     228                    Worker thread stack used (stack size 1088)
            All done, main thrd : stack used   704 size  2048
            All done : Idlethread stack used   172 size  1280

Timing complete - 29820 ms total

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