[PATCH 1/3] optee: Add an helper to add the optee firmware node in the FDT

[Alban Bedel]

Some platforms can detect if an optee firmware is running and then
manually add the firmware node to the FDT. Provide a common helper to
avoid code duplication in the board code.

Signed-off-by: Alban Bedel <alban.be...@aerq.com>
---
 include/tee/optee.h | 11 +++++++++
 lib/optee/optee.c   | 60 +++++++++++++++++++++++++++++++++------------
 2 files changed, 55 insertions(+), 16 deletions(-)

diff --git a/include/tee/optee.h b/include/tee/optee.h
index 5412bc7386ec..d9a316150522 100644
--- a/include/tee/optee.h
+++ b/include/tee/optee.h
@@ -58,11 +58,22 @@ static inline int optee_verify_bootm_image(unsigned long 
image_addr,

 #if defined(CONFIG_OPTEE_LIB) && defined(CONFIG_OF_LIBFDT)
 int optee_copy_fdt_nodes(void *new_blob);
+
+int optee_add_firmware_node(void *fdt_blob,
+                           const char *compatible,
+                           const char *method);
 #else
 static inline int optee_copy_fdt_nodes(void *new_blob)
 {
        return 0;
 }
+
+static inline int optee_add_firmware_node(void *fdt_blob,
+                                         const char *compatible,
+                                         const char *method)
+{
+       return 0;
+}
 #endif

 #endif /* _OPTEE_H */
diff --git a/lib/optee/optee.c b/lib/optee/optee.c
index b03622404469..8d4e110dfd04 100644
--- a/lib/optee/optee.c
+++ b/lib/optee/optee.c
@@ -65,10 +65,10 @@ error:
 #endif

 #if defined(CONFIG_OF_LIBFDT)
-static int optee_copy_firmware_node(ofnode node, void *fdt_blob)
+static int optee_set_firmware_node(void *fdt_blob, const char *compatible,
+                                  const char *method)
 {
-       int offs, ret, len;
-       const void *prop;
+       int offs, ret;

        offs = fdt_path_offset(fdt_blob, "/firmware");
        if (offs < 0) {
@@ -85,29 +85,32 @@ static int optee_copy_firmware_node(ofnode node, void 
*fdt_blob)
        if (offs < 0)
                return offs;

+       ret = fdt_setprop_string(fdt_blob, offs, "compatible", compatible);
+       if (ret < 0)
+               return ret;
+
+       return fdt_setprop_string(fdt_blob, offs, "method", method);
+}
+
+static int optee_copy_firmware_node(ofnode node, void *fdt_blob)
+{
+       const char *compatible, *method;
+
        /* copy the compatible property */
-       prop = ofnode_get_property(node, "compatible", &len);
-       if (!prop) {
+       compatible = ofnode_read_string(node, "compatible");
+       if (!compatible) {
                debug("missing OP-TEE compatible property");
                return -EINVAL;
        }

-       ret = fdt_setprop(fdt_blob, offs, "compatible", prop, len);
-       if (ret < 0)
-               return ret;
-
        /* copy the method property */
-       prop = ofnode_get_property(node, "method", &len);
-       if (!prop) {
+       method = ofnode_read_string(node, "method");
+       if (!method) {
                debug("missing OP-TEE method property");
                return -EINVAL;
        }

-       ret = fdt_setprop(fdt_blob, offs, "method", prop, len);
-       if (ret < 0)
-               return ret;
-
-       return 0;
+       return optee_set_firmware_node(fdt_blob, compatible, method);
 }

 int optee_copy_fdt_nodes(void *new_blob)
@@ -190,4 +193,29 @@ int optee_copy_fdt_nodes(void *new_blob)

        return 0;
 }
+
+int optee_add_firmware_node(void *fdt_blob, const char *compatible,
+                           const char *method)
+{
+       int ret;
+
+       /*
+        * Do not proceed if the target dt already has an OP-TEE node.
+        * In this case assume that the system knows better somehow,
+        * so do not interfere.
+        */
+       if (fdt_check_header(fdt_blob))
+               return -EINVAL;
+
+       if (fdt_path_offset(fdt_blob, "/firmware/optee") >= 0) {
+               debug("OP-TEE Device Tree node already exists in target");
+               return 0;
+       }
+
+       ret = fdt_increase_size(fdt_blob, 512);
+       if (ret)
+               return ret;
+
+       return optee_set_firmware_node(fdt_blob, compatible, method);
+}
 #endif
--
2.34.1

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