Add support for AArch32

gcc version 4.9.2 (Raspbian 4.9.2-10)
Tested on Linux raspberrypi 4.4.6-v7+ #875 SMP Tue Apr 12 16:33:02 BST 2016 armv7l GNU/Linux

CPUs may be little or big endian, detect with gcc flags, not the processor architecture
Add a new flag $(PLATFORM)_uses_openssl which allows to disable the link with openssl lib.

vlib/vlib/threads.c:
startup.conf must:
- specify the heapsize as we don't have hugepages on raspbian

cpu {
  main-core 3
}
heapsize 64M

Corrects in various files the assumption uword == u64 and replaces 'u64' cast with 'pointer_to_uword' and 'uword_to_pointer' where appropriate.
256 CPUs may create an OOM when testing with small memory footprint ( heapsize 64M ), allows the number of VLIB_MAX_CPUS to be set in platforms/*.mk

vppinfra/vppinfra/longjmp.S:
ARM - copy r1 (1st parameter of the setjmp call) to r0 (return value)

vppinfra/vppinfra/time.h:
On ARMv7 in AArch32 mode, we can access to a 64bit register to retreive the cycles count.
gcc on rpi only declare ARM_ARCH 6. Override this info, and check if it is possible to use 'mrrc'.
/!\ the time function will NOT work without allowing the user mode access to the PMU.
You may download the source of the kmod here:
https://github.com/christophefontaine/arm_rdtsc

Change-Id: I8142606436d9671a184133b935398427f08a8bd2
Signed-off-by: Christophe Fontaine <christophe.fontaine@qosmos.com>

3 files changed, 10 insertions, 10 deletions

diff --git a/vnet/vnet/devices/ssvm/node.c b/vnet/vnet/devices/ssvm/node.c
index b26d73d12b8..3a5709d0323 100644
--- a/vnet/vnet/devices/ssvm/node.c
+++ b/vnet/vnet/devices/ssvm/node.c
@@ -97,8 +97,8 @@ ssvm_eth_device_input (ssvm_eth_main_t * em,
   uword n_trace = vlib_get_trace_count (vm, node);
 
   /* Either side down? buh-bye... */
-  if ((u64)(sh->opaque [MASTER_ADMIN_STATE_INDEX]) == 0 ||
-      (u64)(sh->opaque [SLAVE_ADMIN_STATE_INDEX]) == 0)
+  if (pointer_to_uword(sh->opaque [MASTER_ADMIN_STATE_INDEX]) == 0 ||
+      pointer_to_uword(sh->opaque [SLAVE_ADMIN_STATE_INDEX]) == 0)
     return 0;
 
   if (intfc->i_am_master)
@@ -271,14 +271,14 @@ ssvm_eth_device_input (ssvm_eth_main_t * em,
 
   ASSERT(vec_len(intfc->rx_queue) > 0);
 
-  n_available = (u32)(u64)(sh->opaque[CHUNK_POOL_NFREE]);
+  n_available = (u32)pointer_to_uword(sh->opaque[CHUNK_POOL_NFREE]);
   elt_indices = (u32 *)(sh->opaque[CHUNK_POOL_FREELIST_INDEX]);
 
   memcpy (&elt_indices[n_available], intfc->rx_queue, 
           vec_len (intfc->rx_queue) * sizeof (u32));
 
   n_available += vec_len (intfc->rx_queue);
-  sh->opaque[CHUNK_POOL_NFREE] = (void *) (u64) n_available;
+  sh->opaque[CHUNK_POOL_NFREE] = uword_to_pointer(n_available, void* );
 
   ssvm_unlock (sh);
 
diff --git a/vnet/vnet/devices/ssvm/ssvm_eth.c b/vnet/vnet/devices/ssvm/ssvm_eth.c
index 7d937f07937..23ec0261325 100644
--- a/vnet/vnet/devices/ssvm/ssvm_eth.c
+++ b/vnet/vnet/devices/ssvm/ssvm_eth.c
@@ -95,7 +95,7 @@ int ssvm_eth_create (ssvm_eth_main_t * em, u8 * name, int is_master)
 
   sh->opaque [CHUNK_POOL_INDEX] = (void *) elts;
   sh->opaque [CHUNK_POOL_FREELIST_INDEX] = (void *) elt_indices;
-  sh->opaque [CHUNK_POOL_NFREE] = (void *) em->nbuffers;
+  sh->opaque [CHUNK_POOL_NFREE] = (void *)(uword) em->nbuffers;
   
   ssvm_pop_heap (oldheap);
 
@@ -276,8 +276,8 @@ ssvm_eth_interface_tx (vlib_main_t * vm,
   n_present_in_cache = vec_len (em->chunk_cache);
 
   /* admin / link up/down check */
-  if ((u64)(sh->opaque [MASTER_ADMIN_STATE_INDEX]) == 0 ||
-      (u64)(sh->opaque [SLAVE_ADMIN_STATE_INDEX]) == 0)
+  if (sh->opaque [MASTER_ADMIN_STATE_INDEX] == 0 ||
+      sh->opaque [SLAVE_ADMIN_STATE_INDEX] == 0)
     {
       interface_down = 1;
       goto out;
@@ -287,7 +287,7 @@ ssvm_eth_interface_tx (vlib_main_t * vm,
 
   elts = (ssvm_eth_queue_elt_t *) (sh->opaque [CHUNK_POOL_INDEX]);
   elt_indices = (u32 *) (sh->opaque [CHUNK_POOL_FREELIST_INDEX]);
-  n_available = (u32) (u64) (sh->opaque [CHUNK_POOL_NFREE]);
+  n_available = (u32) pointer_to_uword(sh->opaque [CHUNK_POOL_NFREE]);
 
   if (n_present_in_cache < n_left*2)
     {
@@ -305,7 +305,7 @@ ssvm_eth_interface_tx (vlib_main_t * vm,
 
       n_present_in_cache += n_allocated;
       n_available -= n_allocated;
-      sh->opaque [CHUNK_POOL_NFREE] = (void *) (u64) n_available;
+      sh->opaque [CHUNK_POOL_NFREE] = uword_to_pointer(n_available, void*);
       _vec_len (em->chunk_cache) = n_present_in_cache;
     }
 
diff --git a/vnet/vnet/devices/ssvm/ssvm_eth.h b/vnet/vnet/devices/ssvm/ssvm_eth.h
index 8f1f88964c2..23af7ed5ae8 100644
--- a/vnet/vnet/devices/ssvm/ssvm_eth.h
+++ b/vnet/vnet/devices/ssvm/ssvm_eth.h
@@ -114,7 +114,7 @@ static inline void ssvm_eth_validate_freelists (int need_lock)
         ssvm_lock (sh, my_pid, 15);
 
       elt_indices = (u32 *) (sh->opaque [CHUNK_POOL_FREELIST_INDEX]);
-      n_available = (u32) (u64) (sh->opaque [CHUNK_POOL_NFREE]);
+      n_available = (u32) (uword) (sh->opaque [CHUNK_POOL_NFREE]);
 
       for (i = 0; i < n_available; i++)
 	ASSERT (elt_indices[i] < 2048);