i2c device initialization on MVME3100 RTEMS5 (presumably also in 6?)

[Heinz Junkes]

We had a problem initialising the i2c devices on the MVME3100.
Unfortunately, I still don't understand the order of initialisation.

However, the direct driver initialisation from bspstart no longer worked as it did with older versions. 

My workaround therefore looks like this:

rtems at rtems-dev:~/MVME3100/kernel$ git diff bsps/powerpc/mvme3100/start/bspstart.c
diff --git a/bsps/powerpc/mvme3100/start/bspstart.c b/bsps/powerpc/mvme3100/start/bspstart.c
index 0ec215e33b..96d6e2f9cd 100644
--- a/bsps/powerpc/mvme3100/start/bspstart.c
+++ b/bsps/powerpc/mvme3100/start/bspstart.c
@@ -52,6 +52,8 @@
 extern unsigned long __rtems_end[];
 extern unsigned      ppc_exc_lock_std, ppc_exc_gpr3_std;

+extern bool _IO_All_drivers_initialized;
+
 /*
  * Copy Additional boot param passed by boot loader
  */
@@ -419,7 +421,14 @@ void bsp_start( void )

 static void mvme3100_i2c_initialize(void)
 {
+  printk("-------- call BSP_i2c_initialize() with _IO_All_drivers_initialized = true\n");
+  /*
+   * we need the drivers registered as they appear, due to get
+   * the i2c devices ready
+   */
+  _IO_All_drivers_initialized = true;
   BSP_i2c_initialize();
+  _IO_All_drivers_initialized = false;
 }

 RTEMS_SYSINIT_ITEM(


You can find this in cpukit/sapi/src/ioregisterdriver.c:


 if ( _IO_All_drivers_initialized ) {
    /* Other drivers have already been initialized, we initialize
     * the driver directly.
     */
    return rtems_io_initialize( major, 0, NULL );
  } else {
    /* The driver will be initialized together with all other drivers
     * in a later stage by _IO_Initialize_all_drivers().
     */
    return RTEMS_SUCCESSFUL;
  }


I can imagine that this is not an elegant way, but it's the best I could do. Is there any idea how to do it "right"?
Or should I submit this patch?


Viele Grüße
Heinz Junkes
--
Experience directly varies with equipment ruined.