Added comments.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@11774 110e8d01-0319-4d1e-a829-52ad28d1bb01

1 files changed, 44 insertions, 0 deletions

diff --git a/demos/ATSAMA5D2/RT-SAMA5D2-XPLAINED-SEC/proxies/tssockstub.c b/demos/ATSAMA5D2/RT-SAMA5D2-XPLAINED-SEC/proxies/tssockstub.c
index 05e222c37..04b1115e3 100644
--- a/demos/ATSAMA5D2/RT-SAMA5D2-XPLAINED-SEC/proxies/tssockstub.c
+++ b/demos/ATSAMA5D2/RT-SAMA5D2-XPLAINED-SEC/proxies/tssockstub.c
@@ -82,6 +82,21 @@ static bool isOpValid(stub_op_t *op)
   return TRUE;

 }

 

+/**

+ * @brief   Simulate an a call to a NSEC function.

+ * @details It activates the channel between the stubs service and

+ *          the skels daemon running in the nsec world.

+ *          To do it, it uses an event to signal the skels

+ *          daemon that a new op request is ready to be executed.

+ *          The skels daemon will then, behind the scenes, gets the op calling,

+ *          via smc, the stubs service. The skel executes it and then calls the

+ *          stubs service again to post the result and to wake up the

+ *          calling thread of this function.

+ *

+ * @param[in] op    the 'remote' method description.

+ *

+ * @return          the return value of 'remote' method.

+ */

 static uint32_t callRemote(stub_op_t *op) {

   uint32_t r;

 

@@ -131,6 +146,8 @@ THD_FUNCTION(TsStubsService, tsstate) {
 

     switch (skrp->req) {

     case SKEL_REQ_GETOP:

+

+      /* The nsec skel calls us to get a new op ready to be executed.*/

       if (chFifoReceiveObjectTimeout(&ops_fifo, (void **)&op, TIME_IMMEDIATE) ==

             MSG_TIMEOUT) {

         r = SMC_SVC_NHND;

@@ -138,6 +155,8 @@ THD_FUNCTION(TsStubsService, tsstate) {
       }

       skrp->stub_op = (uint32_t)op;

       skrp->stub_op_code = op->op_code;

+

+      /* Pass all the 'by value' arguments.*/

       for (i = 0; i < METHOD_MAX_PARAMS; ++i) {

         if (op->op_p[i].dir == OP_PRMDIR_NONE)

           skrp->stub_op_p[i] = op->op_p[i].val;

@@ -146,12 +165,23 @@ THD_FUNCTION(TsStubsService, tsstate) {
       break;

 

     case SKEL_REQ_CPYPRMS:

+

+      /* The nsec skel calls us to get a copy of the 'in' parameters of

+         the specified op.

+         An 'in' parameter is an indirect argument, that is an argument

+         the value of which is a pointer to a memory buffer, that

+         must be copied in a non secure memory buffer.

+         It represents data to be consumed by the callee.*/

       op = (stub_op_t *)skrp->stub_op;

       if (!isOpValid(op) || op->op_state != PENDING ||

             op->op_code != skrp->stub_op_code) {

         r = SMC_SVC_INVALID;

         break;

       }

+

+      /* Copy all 'in' parameters.

+         For each parameter check that the destination memory area

+         is in the non secure memory arena.*/

       for (i = 0; i < METHOD_MAX_PARAMS; ++i) {

         if ((op->op_p[i].dir & OP_PRMDIR_IN) == 0)

           continue;

@@ -165,12 +195,23 @@ THD_FUNCTION(TsStubsService, tsstate) {
       break;

 

     case SKEL_REQ_PUTRES:

+

+      /* The nsec skel calls us to put a copy of the 'out' parameters of

+         the specified op.

+         An 'out' parameter is an indirect argument, that is an argument

+         the value of which is a pointer to a memory buffer, that

+         must be copied in a secure memory buffer.

+         It represents data produced by the callee.*/

       op = (stub_op_t *)skrp->stub_op;

       if (!isOpValid(op) || op->op_state != PENDING ||

             op->op_code != skrp->stub_op_code) {

         r = SMC_SVC_INVALID;

         break;

       }

+

+      /* Copy all 'out' parameters.

+         For each parameter check that the source memory area

+         is in the non secure memory arena.*/

       for (i = 0; i < METHOD_MAX_PARAMS; ++i) {

         if ((op->op_p[i].dir & OP_PRMDIR_OUT) == 0)

           continue;

@@ -183,6 +224,9 @@ THD_FUNCTION(TsStubsService, tsstate) {
       }

       if (r != SMC_SVC_OK)

         break;

+

+      /* Set the return value of the 'remote' callee method,

+         and wake up the secure caller.*/

       op->op_code = skrp->stub_op_result;

       chThdResume(&op->op_wthdp, MSG_OK);

       break;