From 4daaaccb0f16a1ffe6069edf9748e4f81cbfcd1a Mon Sep 17 00:00:00 2001
From: Jose Alamos <jose@alamos.cc>
Date: Wed, 17 Aug 2022 14:39:45 +0200
Subject: [PATCH] pkg/lwip_netdev: add support for IPC based Bottom Half
 Processor

---
 pkg/lwip/Makefile.dep                 |  3 +++
 pkg/lwip/contrib/netdev/lwip_netdev.c |  9 ++++++++-
 pkg/lwip/include/lwip/netif/compat.h  | 24 ++++++++++++++++++++++++
 3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/pkg/lwip/Makefile.dep b/pkg/lwip/Makefile.dep
index 07cf924753..29a1089e9e 100644
--- a/pkg/lwip/Makefile.dep
+++ b/pkg/lwip/Makefile.dep
@@ -89,6 +89,9 @@ endif
 ifneq (,$(filter lwip_contrib,$(USEMODULE)))
   USEMODULE += sema
   USEMODULE += ztimer_msec
+  ifneq (,$(filter bhp,$(USEMODULE)))
+    USEMODULE += bhp_msg
+  endif
 endif
 
 ifneq (,$(filter lwip_netif,$(USEMODULE)))
diff --git a/pkg/lwip/contrib/netdev/lwip_netdev.c b/pkg/lwip/contrib/netdev/lwip_netdev.c
index 7040229483..df035f30d7 100644
--- a/pkg/lwip/contrib/netdev/lwip_netdev.c
+++ b/pkg/lwip/contrib/netdev/lwip_netdev.c
@@ -87,7 +87,11 @@ err_t lwip_netdev_init(struct netif *netif)
         }
     }
 
-    /* initialize netdev and netif */
+    /* initialize Bottom Half Processor, netdev and netif */
+    if (IS_USED(MODULE_BHP_MSG)) {
+        bhp_msg_claim_thread(lwip_netif_get_bhp(netif), _pid);
+    }
+
     netdev = netif->state;
     lwip_netif_dev_acquire(netif);
     netdev->driver->init(netdev);
@@ -333,6 +337,9 @@ static void *_event_loop(void *arg)
             dev->driver->isr(dev);
             lwip_netif_dev_release(netif);
         }
+        else if (IS_USED(MODULE_BHP_MSG) && msg.type == BHP_MSG_BH_REQUEST) {
+            bhp_msg_handler(&msg);
+        }
     }
     return NULL;
 }
diff --git a/pkg/lwip/include/lwip/netif/compat.h b/pkg/lwip/include/lwip/netif/compat.h
index 507b3bb38a..a01952ae4a 100644
--- a/pkg/lwip/include/lwip/netif/compat.h
+++ b/pkg/lwip/include/lwip/netif/compat.h
@@ -22,6 +22,7 @@
 
 #include "lwip/netif.h"
 #include "net/netif.h"
+#include "bhp/msg.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -34,6 +35,9 @@ typedef struct {
     netif_t common_netif;                /**< network interface descriptor */
     struct netif lwip_netif;             /**< lwIP interface data */
     rmutex_t lock;                       /**< lock for the interface */
+#if IS_USED(MODULE_BHP_MSG)
+    bhp_msg_t bhp;                       /**< IPC Bottom Half Processor */
+#endif
 } lwip_netif_t;
 
 /**
@@ -69,6 +73,26 @@ static inline void lwip_netif_dev_release(struct netif *netif)
     rmutex_unlock(&compat_netif->lock);
 }
 
+/**
+ * @brief Get the IPC based Bottom Half Processor for LWIP
+ *
+ * @param[in]   netif pointer to the LWIP network interface
+ *
+ * @return      pointer to the IPC based Bottom Half Processor descriptor, if
+ *              @ref sys_bhp_msg is present.
+ * @return      NULL otherwise
+ */
+static inline bhp_msg_t *lwip_netif_get_bhp(struct netif *netif)
+{
+#if IS_USED(MODULE_BHP_MSG)
+    lwip_netif_t *compat_netif = container_of(netif, lwip_netif_t, lwip_netif);
+    return &compat_netif->bhp;
+#else
+    (void) netif;
+    return NULL;
+#endif
+}
+
 #ifdef __cplusplus
 }
 #endif