Support multiple XML files per folder

12 files changed, 324 insertions, 205 deletions

diff --git a/docs/ToDo b/docs/ToDo
index c42e000..0c54eea 100644
--- a/docs/ToDo
+++ b/docs/ToDo
@@ -1,23 +1,30 @@
 High Priority (we would need it for IPE Camera)
 =============
- 1. Join multiple XML files and on error use simplified XSD scheme on all files to find the file causing error
+ 1. DMA without ring buffer, just send data in the newly configured buffers while there is the space...
+    * We need a way to add (remove?) pages into the same use. Some times in the middle of existing pages, i.e. tructuring seems complicated.
+    * vmsplice them out trough the device?
+ 2. Allow DMA into the user pages
+    * Dangerous as hardware accessed memory is only valid during life-time of one application. Instead the kernel pages can be re-assembled as big buffer using vmmngr_map_page (?)
+ 3. Use huge-pages + dynamicaly configure DMA page size
+ 4. DirectGMA/GPUDirect support
+ 5. High-speed interface to Infiniband
  
 Normal Priority (it would make just few things a bit easier)
 ===============
- 1. Implement pcilib_configure_autotrigger
- 2. Provide OR and AND operations on registers in cli
- 3. Support writting a data from a binary file in cli
- 4. Support Python-scripts in a views, we need to provide python function to read registers/properties...
- 5. Really check the specified min, max values while setting registers
+ 1. Support Python-scripts in the views (we need to provide python API to read registers/properties)
+ 2. Integrate base streaming model into the pcitool
+ 3. Implement pcilib_configure_autotrigger
+ 4. Really check the specified min, max values while setting registers
+ 5. Provide OR and AND operations on registers in cli
+ 6. Support writting a data from a binary file in cli
 
 Low Priority (only as generalization for other projects)
 ============
- 1. Shall we allow overriding of registers?
+ 1. We managed kmem performance using next kmem prediction, but it is still wise to provide additionally a binary tree for faster search
  2. Support for Network Registers and Network DMA
  3. Define a syntax for register dependencies / delays (?)
  4. Use pthread_condition_t instead of polling
  5. Support FIFO reads/writes from/to registers
- 6. We managed kmem performance using next kmem prediction, but it is still wise to provide additionally a binary tree for faster search
 
 Performance
 ===========
diff --git a/pcilib/xml.c b/pcilib/xml.c
index 1238ba8..bc48a34 100644
--- a/pcilib/xml.c
+++ b/pcilib/xml.c
@@ -78,6 +78,17 @@ static xmlNodePtr pcilib_xml_get_parent_register_node(xmlDocPtr doc, xmlNodePtr
 }
 */
 
+int pcilib_get_xml_attr(pcilib_t *ctx, pcilib_xml_node_t *node, const char *attr, pcilib_value_t *val) {
+    xmlAttr *prop;
+    xmlChar *str;
+
+    prop = xmlHasProp(node, BAD_CAST attr);
+    if ((!prop)||(!prop->children)) return PCILIB_ERROR_NOTFOUND;
+
+    str = prop->children->content;
+    return pcilib_set_value_from_static_string(ctx, val, (const char*)str);
+}
+
 static int pcilib_xml_parse_view_reference(pcilib_t *ctx, xmlDocPtr doc, xmlNodePtr node, pcilib_view_reference_t *desc) {
     xmlAttr *cur;
     char *value, *name;
@@ -873,11 +884,14 @@ static int pcilib_xml_process_document(pcilib_t *ctx, xmlDocPtr doc, xmlXPathCon
     return 0;
 }
 
-static int pcilib_xml_load_xsd(pcilib_t *ctx, char *xsd_filename) {
+static int pcilib_xml_load_xsd_file(pcilib_t *ctx, char *xsd_filename, xmlSchemaPtr *schema, xmlSchemaValidCtxtPtr *validator) {
     int err;
 
     xmlSchemaParserCtxtPtr ctxt;
 
+    *schema = NULL;
+    *validator = NULL;
+
     /** we first parse the xsd file for AST with validation*/
     ctxt = xmlSchemaNewParserCtxt(xsd_filename);
     if (!ctxt) {
@@ -887,8 +901,8 @@ static int pcilib_xml_load_xsd(pcilib_t *ctx, char *xsd_filename) {
         return PCILIB_ERROR_FAILED;
     }
 
-    ctx->xml.schema = xmlSchemaParse(ctxt);
-    if (!ctx->xml.schema) {
+    *schema = xmlSchemaParse(ctxt);
+    if (!*schema) {
         xmlErrorPtr xmlerr = xmlGetLastError();
         xmlSchemaFreeParserCtxt(ctxt);
         if (xmlerr) pcilib_error("Failed to parse XML schema, xmlSchemaParse reported error %d - %s", xmlerr->code, xmlerr->message);
@@ -898,15 +912,15 @@ static int pcilib_xml_load_xsd(pcilib_t *ctx, char *xsd_filename) {
 
     xmlSchemaFreeParserCtxt(ctxt);
 
-    ctx->xml.validator  = xmlSchemaNewValidCtxt(ctx->xml.schema);
-    if (!ctx->xml.validator) {
+    *validator  = xmlSchemaNewValidCtxt(*schema);
+    if (!*validator) {
         xmlErrorPtr xmlerr = xmlGetLastError();
         if (xmlerr) pcilib_error("xmlSchemaNewValidCtxt reported error %d - %s", xmlerr->code, xmlerr->message);
         else pcilib_error("Failed to create a validation context");
         return PCILIB_ERROR_FAILED;
     }
 
-    err = xmlSchemaSetValidOptions(ctx->xml.validator, XML_SCHEMA_VAL_VC_I_CREATE);
+    err = xmlSchemaSetValidOptions(*validator, XML_SCHEMA_VAL_VC_I_CREATE);
     if (err) {
         xmlErrorPtr xmlerr = xmlGetLastError();
         if (xmlerr) pcilib_error("xmlSchemaSetValidOptions reported error %d - %s", xmlerr->code, xmlerr->message);
@@ -917,16 +931,45 @@ static int pcilib_xml_load_xsd(pcilib_t *ctx, char *xsd_filename) {
     return 0;
 }
 
-static int pcilib_xml_load_file(pcilib_t *ctx, const char *path, const char *name) {
+
+static int pcilib_xml_load_xsd(pcilib_t *ctx, char *model_dir) {
+    int err;
+
+    struct stat st;
+    char *xsd_path;
+
+    xsd_path = (char*)alloca(strlen(model_dir) + 32);
+    if (!xsd_path) return PCILIB_ERROR_MEMORY;
+
+    sprintf(xsd_path, "%s/model.xsd", model_dir);
+    if (stat(xsd_path, &st)) {
+        pcilib_info("XML models are not present, missing parts schema");
+        return PCILIB_ERROR_NOTFOUND;
+    }
+
+    err = pcilib_xml_load_xsd_file(ctx, xsd_path, &ctx->xml.parts_schema, &ctx->xml.parts_validator);
+    if (err) return err;
+
+    sprintf(xsd_path, "%s/references.xsd", model_dir);
+    if (stat(xsd_path, &st)) {
+        pcilib_info("XML models are not present, missing schema");
+        return PCILIB_ERROR_NOTFOUND;
+    }
+
+    return pcilib_xml_load_xsd_file(ctx, xsd_path, &ctx->xml.schema, &ctx->xml.validator);
+}
+
+
+
+static xmlDocPtr pcilib_xml_load_file(pcilib_t *ctx, const char *path, const char *name) {
     int err;
     char *full_name;
     xmlDocPtr doc;
-    xmlXPathContextPtr xpath;
 
     full_name = (char*)alloca(strlen(path) + strlen(name) + 2);
     if (!name) {
         pcilib_error("Error allocating %zu bytes of memory in stack to create a file name", strlen(path) + strlen(name) + 2);
-        return PCILIB_ERROR_MEMORY;
+        return NULL;
     }
 
     sprintf(full_name, "%s/%s", path, name);
@@ -936,104 +979,139 @@ static int pcilib_xml_load_file(pcilib_t *ctx, const char *path, const char *nam
         xmlErrorPtr xmlerr = xmlCtxtGetLastError(ctx->xml.parser);
         if (xmlerr) pcilib_error("Error parsing %s, xmlCtxtReadFile reported error %d - %s", full_name, xmlerr->code, xmlerr->message);
         else pcilib_error("Error parsing %s", full_name);
-        return PCILIB_ERROR_INVALID_DATA;
+        return NULL;
     }
 
-    err = xmlSchemaValidateDoc(ctx->xml.validator, doc);
+    err = xmlSchemaValidateDoc(ctx->xml.parts_validator, doc);
     if (err) {
         xmlErrorPtr xmlerr = xmlCtxtGetLastError(ctx->xml.parser);
         xmlFreeDoc(doc);
         if (xmlerr) pcilib_error("Error validating %s, xmlSchemaValidateDoc reported error %d - %s", full_name, xmlerr->code, xmlerr->message);
         else pcilib_error("Error validating %s", full_name);
-        return PCILIB_ERROR_VERIFY;
-    }
-
-    xpath = xmlXPathNewContext(doc);
-    if (!xpath) {
-        xmlErrorPtr xmlerr = xmlGetLastError();
-        xmlFreeDoc(doc);
-        if (xmlerr) pcilib_error("Document %s: xmlXpathNewContext reported error %d - %s for document %s", full_name, xmlerr->code, xmlerr->message);
-        else pcilib_error("Error creating XPath context for %s", full_name);
-        return PCILIB_ERROR_FAILED;
-    }
-
-    // This can only partially fail... Therefore we need to keep XML and just return the error...
-    err = pcilib_xml_process_document(ctx, doc, xpath);
-
-    if (ctx->xml.num_files == PCILIB_MAX_MODEL_FILES) {
-        xmlFreeDoc(doc);
-        xmlXPathFreeContext(xpath);
-        pcilib_error("Too many XML files for a model, only up to %zu are supported", PCILIB_MAX_MODEL_FILES);
-        return PCILIB_ERROR_TOOBIG;
+        return NULL;
     }
 
-    ctx->xml.docs[ctx->xml.num_files] = doc;
-    ctx->xml.xpath[ctx->xml.num_files] = xpath;
-    ctx->xml.num_files++;
-
-    return err;
+    return doc;
 }
 
-
-int pcilib_process_xml(pcilib_t *ctx, const char *location) {
+static int pcilib_process_xml_internal(pcilib_t *ctx, const char *model, const char *location) {
     int err;
 
     DIR *rep;
     struct dirent *file = NULL;
     char *model_dir, *model_path;
 
+    xmlDocPtr doc = NULL;
+    xmlNodePtr root = NULL;
+    xmlXPathContextPtr xpath;
+
+    if (ctx->xml.num_files == PCILIB_MAX_MODEL_FILES) {
+        pcilib_error("Too many XML locations for a model, only up to %zu are supported", PCILIB_MAX_MODEL_FILES);
+        return PCILIB_ERROR_TOOBIG;
+    }
+
     model_dir = getenv("PCILIB_MODEL_DIR");
     if (!model_dir) model_dir = PCILIB_MODEL_DIR;
 
-    model_path = (char*)alloca(strlen(model_dir) + strlen(location) + 2);
+    if (!model) model = ctx->model;
+    if (!location) location = "";
+
+    model_path = (char*)alloca(strlen(model_dir) + strlen(model) + strlen(location) + 3);
     if (!model_path) return PCILIB_ERROR_MEMORY;
 
-    sprintf(model_path, "%s/%s", model_dir, location);
+    sprintf(model_path, "%s/%s/%s", model_dir, model, location);
 
     rep = opendir(model_path);
     if (!rep) return PCILIB_ERROR_NOTFOUND;
 
     while ((file = readdir(rep)) != NULL) {
+        xmlDocPtr newdoc;
+        
         size_t len = strlen(file->d_name);
         if ((len < 4)||(strcasecmp(file->d_name + len - 4, ".xml"))) continue;
         if (file->d_type != DT_REG) continue;
 
-        err = pcilib_xml_load_file(ctx, model_path, file->d_name);
-        if (err) pcilib_error("Error processing XML file %s", file->d_name);
-    }
+        newdoc = pcilib_xml_load_file(ctx, model_path, file->d_name);
+        if (!newdoc) {
+            pcilib_error("Error processing XML file %s", file->d_name);
+            continue;
+        }
+
+        if (doc) {
+            xmlNodePtr node;
 
+            node = xmlDocGetRootElement(newdoc);
+            if (node) node = xmlFirstElementChild(node);
+            if (node) node = xmlDocCopyNodeList(doc, node);
+            xmlFreeDoc(newdoc);
+
+            if ((!node)||(!xmlAddChildList(root, node))) {
+                xmlErrorPtr xmlerr = xmlCtxtGetLastError(ctx->xml.parser);
+                if (node) xmlFreeNode(node);
+                if (xmlerr) pcilib_error("Error manipulating XML tree of %s, libXML2 reported error %d - %s", file->d_name, xmlerr->code, xmlerr->message);
+                else pcilib_error("Error manipulating XML tree of %s", file->d_name);
+                continue;
+            }
+        } else {
+            root = xmlDocGetRootElement(newdoc);
+            if (!root) {
+                xmlErrorPtr xmlerr = xmlCtxtGetLastError(ctx->xml.parser);
+                xmlFreeDoc(newdoc);
+                if (xmlerr) pcilib_error("Error manipulating XML tree of %s, libXML2 reported error %d - %s", file->d_name, xmlerr->code, xmlerr->message);
+                else pcilib_error("Error manipulating XML tree of %s", file->d_name);
+                continue;
+            }
+            doc = newdoc;
+                // This is undocumented, but should be fine...
+            if (doc->URL) xmlFree((xmlChar*)doc->URL);
+            doc->URL = xmlStrdup(BAD_CAST model_path);
+        }
+    }
     closedir(rep);
 
-    return 0;
+    if (!doc)
+        return 0;
+
+    err = xmlSchemaValidateDoc(ctx->xml.validator, doc);
+    if (err) {
+        xmlErrorPtr xmlerr = xmlCtxtGetLastError(ctx->xml.parser);
+        xmlFreeDoc(doc);
+        if (xmlerr) pcilib_error("Error validating %s, xmlSchemaValidateDoc reported error %d - %s", model_path, xmlerr->code, xmlerr->message);
+        else pcilib_error("Error validating %s", model_path);
+        return PCILIB_ERROR_VERIFY;
+    }
+
+    xpath = xmlXPathNewContext(doc);
+    if (!xpath) {
+        xmlErrorPtr xmlerr = xmlGetLastError();
+        xmlFreeDoc(doc);
+        if (xmlerr) pcilib_error("Document %s: xmlXpathNewContext reported error %d - %s for document %s", model_path, xmlerr->code, xmlerr->message);
+        else pcilib_error("Error creating XPath context for %s", model_path);
+        return PCILIB_ERROR_FAILED;
+    }
+
+        // This can only partially fail... Therefore we need to keep XML and just return the error...
+    err = pcilib_xml_process_document(ctx, doc, xpath);
+
+    ctx->xml.docs[ctx->xml.num_files] = doc;
+    ctx->xml.xpath[ctx->xml.num_files] = xpath;
+    ctx->xml.num_files++;
+
+    return err;
 }
 
+int pcilib_process_xml(pcilib_t *ctx, const char *location) {
+    return pcilib_process_xml_internal(ctx, NULL, location);
+}
 
-/** pcilib_init_xml
- * this function will initialize the registers and banks from the xml files
- * @param[in,out] ctx the pciilib_t running that gets filled with structures
- * @param[in] model the current model of ctx
- * @return an error code
- */
 int pcilib_init_xml(pcilib_t *ctx, const char *model) {
     int err;
 
     char *model_dir;
-    char *xsd_path;
-
-    struct stat st;
 
     model_dir = getenv("PCILIB_MODEL_DIR");
     if (!model_dir) model_dir = PCILIB_MODEL_DIR;
 
-    xsd_path = (char*)alloca(strlen(model_dir) + 16);
-    if (!xsd_path) return PCILIB_ERROR_MEMORY;
-
-    sprintf(xsd_path, "%s/model.xsd", model_dir);
-    if (stat(xsd_path, &st)) {
-        pcilib_info("XML models are not present");
-        return PCILIB_ERROR_NOTFOUND;
-    }
-
     ctx->xml.parser = xmlNewParserCtxt();
     if (!ctx->xml.parser) {
         xmlErrorPtr xmlerr = xmlGetLastError();
@@ -1042,16 +1120,12 @@ int pcilib_init_xml(pcilib_t *ctx, const char *model) {
         return PCILIB_ERROR_FAILED;
     }
 
-    err = pcilib_xml_load_xsd(ctx, xsd_path);
+    err = pcilib_xml_load_xsd(ctx, model_dir);
     if (err) return err;
 
-    return pcilib_process_xml(ctx, model);
+    return pcilib_process_xml_internal(ctx, model, NULL);
 }
 
-/** pcilib_free_xml
- * this function free the xml parts of the pcilib_t running, and some libxml ashes
- * @param[in] pci the pcilib_t running
-*/
 void pcilib_free_xml(pcilib_t *ctx) {
     int i;
 
@@ -1085,7 +1159,16 @@ void pcilib_free_xml(pcilib_t *ctx) {
     if (ctx->xml.schema) {
         xmlSchemaFree(ctx->xml.schema);
         ctx->xml.schema = NULL;
+    }
+
+    if (ctx->xml.parts_validator) {
+        xmlSchemaFreeValidCtxt(ctx->xml.parts_validator);
+        ctx->xml.parts_validator = NULL;
+    }
 
+    if (ctx->xml.parts_schema) {
+        xmlSchemaFree(ctx->xml.parts_schema);
+        ctx->xml.parts_schema = NULL;
     }
 
     if (ctx->xml.parser) {
@@ -1099,14 +1182,3 @@ void pcilib_free_xml(pcilib_t *ctx) {
         xmlMemoryDump();
     */
 }
-
-int pcilib_get_xml_attr(pcilib_t *ctx, pcilib_xml_node_t *node, const char *attr, pcilib_value_t *val) {
-    xmlAttr *prop;
-    xmlChar *str;
-
-    prop = xmlHasProp(node, BAD_CAST attr);
-    if ((!prop)||(!prop->children)) return PCILIB_ERROR_NOTFOUND;
-
-    str = prop->children->content;
-    return pcilib_set_value_from_static_string(ctx, val, (const char*)str);
-}
diff --git a/pcilib/xml.h b/pcilib/xml.h
index 10bc154..e4a5744 100644
--- a/pcilib/xml.h
+++ b/pcilib/xml.h
@@ -28,8 +28,10 @@ struct pcilib_xml_s {
     xmlXPathContextPtr xpath[PCILIB_MAX_MODEL_FILES];	/**< Per-file XPath context */
     
     xmlParserCtxtPtr parser;				/**< Pointer to the XML parser context */
-    xmlSchemaPtr schema;    				/**< Pointer to the parsed xsd schema */
+    xmlSchemaPtr schema;  				/**< Pointer to the parsed xsd schema */
     xmlSchemaValidCtxtPtr validator;       		/**< Pointer to the XML validation context */
+    xmlSchemaPtr parts_schema; 				/**< Pointer to the parsed xsd schema capable of validating individual XML files - no check for cross-references */
+    xmlSchemaValidCtxtPtr parts_validator;     		/**< Pointer to the XML validation context capable of validating individual XML files - no check for cross-references */
 
     xmlNodePtr bank_nodes[PCILIB_MAX_REGISTER_BANKS];	/**< pointer to xml nodes of banks in the xml file */
 };
@@ -38,27 +40,46 @@ struct pcilib_xml_s {
 extern "C" {
 #endif
 
-/**
- * this function gets the xml files and validates them, before filling the pcilib_t struct with the registers and banks of those files
- *@param[in,out] ctx the pcilib_t struct running that gets filled with banks and registers
- *@param[in] model the name of the model
+/** pcilib_init_xml
+ * Initializes XML stack and loads a default set of XML files. The default location for model XML files is
+ * /usr/local/share/pcilib/models/<current_model>. This can be altered using CMake PCILIB_MODEL_DIR variable
+ * while building or using PCILIB_MODEL_DIR environmental variable dynamicly.  More XML files can be added
+ * later using pcilib_process_xml call.
+ * @param[in,out] ctx - pcilib context
+ * @param[in] model - the name of the model
+ * @return - error or 0 on success
  */
 int pcilib_init_xml(pcilib_t *ctx, const char *model);
 
 /** pcilib_free_xml
  * this function free the xml parts of the pcilib_t running, and some libxml ashes
  * @param[in] ctx the pcilib_t running
-*/
+ */
 void pcilib_free_xml(pcilib_t *ctx);
 
-
 /** pcilib_process_xml
- * this function free the xml parts of the pcilib_t running, and some libxml ashes
- * @param[in] ctx the pcilib_t running
- * @param[in] location of XML files relative to the PCILIB_MODEL_DIR
-*/
+ * Processes a bunch of XML files in the specified directory. During the initialization, all XML files
+ * in the corresponding model directory will be loaded. This function allows to additionally load XML 
+ * files from the specified subdirectories of the model directory. I.e. the XML files from the 
+ * /usr/local/share/pcilib/models/<current_model>/<location> will be loaded. As with pcilib_init_xml,
+ * the directory can be adjusted using CMake build configuration or PCILIB_MODEL_DIR environmental
+ * variable.
+ * @param[in] ctx - pcilib context
+ * @param[in] location - Specifies sub-directory with XML files relative to the model directory.
+ * @return - error or 0 on success
+ */
 int pcilib_process_xml(pcilib_t *ctx, const char *location);
 
+/** pcilib_get_xml_attr
+ * This is an internal function which returns a specified node attribute in the pcilib_value_t structure.
+ * This function should not be used directly. Instead subsystem specific calls like pcilib_get_register_attr,
+ * pcilib_get_property_attr, ...have to be used.
+ * @param[in] ctx - pcilib context
+ * @param[in] node - LibXML2 node
+ * @param[in] attr - attribute name
+ * @param[out] val - the result will be returned in this variable. Prior to first usage pcilib_value_t variable should be initalized to 0.
+ * @return - error or 0 on success
+ */
 int pcilib_get_xml_attr(pcilib_t *ctx, pcilib_xml_node_t *node, const char *attr, pcilib_value_t *val);
 
 
diff --git a/xml/model.xsd b/xml/model.xsd
index 1440032..164e887 100644
--- a/xml/model.xsd
+++ b/xml/model.xsd
@@ -4,7 +4,7 @@
 
   <xsd:element name="model">
     <xsd:complexType>
-      <xsd:choice minOccurs="0" maxOccurs="unbounded">
+      <xsd:choice minOccurs="1" maxOccurs="unbounded">
         <xsd:element name="bank" type="pcilib_bank_t" minOccurs="0" maxOccurs="unbounded" />
         <xsd:element name="transform" type="pcilib_transform_view_t" minOccurs="0" maxOccurs="unbounded" />
         <xsd:element name="enum" type="pcilib_enum_view_t" minOccurs="0" maxOccurs="unbounded" />
diff --git a/xml/references.xsd b/xml/references.xsd
index f382840..4474141 100644
--- a/xml/references.xsd
+++ b/xml/references.xsd
@@ -1,9 +1,9 @@
 <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <xsd:include schemaLocation="types.xsd"/>
- 
+
  <xsd:element name="model">
     <xsd:complexType>
-      <xsd:choice minOccurs="0" maxOccurs="unbounded">
+      <xsd:choice minOccurs="1" maxOccurs="unbounded">
         <xsd:element name="bank" type="pcilib_bank_t" minOccurs="0" maxOccurs="unbounded" />
         <xsd:element name="transform" type="pcilib_transform_view_t" minOccurs="0" maxOccurs="unbounded" />
         <xsd:element name="enum" type="pcilib_enum_view_t" minOccurs="0" maxOccurs="unbounded">
@@ -25,30 +25,31 @@
       <xsd:selector xpath="bank" />
       <xsd:field xpath="@name" />
     </xsd:key>
+<!-- Currently, we define all registers, banks, views, and units as xsd:ID which prevents them from sharing name anyway.
+Currently it seems fine, but later it could turn out too be to strict. Then, we get problem also here as transform[@name]
+is ID of view, not register. But how can we restrict transform field to @register only? -->
     <xsd:key name="pcilib_register_key">
-      <xsd:selector xpath="bank/register|bank/register/field" />
-      <xsd:field xpath="@name" />
+      <xsd:selector xpath="bank/register|bank/register/field|transform" />
+      <xsd:field xpath="@name|@register" />
     </xsd:key>
     <xsd:key name="pcilib_view_key">
       <xsd:selector xpath="transform|enum" />
-      <xsd:field xpath="@name" />
+      <xsd:field xpath="@name|@path" />
     </xsd:key>
     <xsd:key name="pcilib_unit_key">
       <xsd:selector xpath="unit" />
       <xsd:field xpath="@name" />
     </xsd:key>
-    <xsd:key name="pcilib_path_key">
-      <xsd:selector xpath="transform" />
-      <xsd:field xpath="@path" />
-    </xsd:key>
 
     <xsd:keyref name="pcilib_register_view_ref" refer="pcilib_view_key">
       <xsd:selector xpath="bank/register/view|bank/register/field/view" />
       <xsd:field xpath="@view" />
     </xsd:keyref>
+<!-- Actually, it is no problem to reference non-existing unit just for informative purposes
     <xsd:keyref name="pcilib_unit_ref" refer="pcilib_unit_key">
       <xsd:selector xpath="transform|enum" />
       <xsd:field xpath="@unit" />
     </xsd:keyref>
+-->
  </xsd:element>
 </xsd:schema>
diff --git a/xml/test/camera.xml b/xml/test/camera.xml
index a84299a..6568f17 100644
--- a/xml/test/camera.xml
+++ b/xml/test/camera.xml
@@ -1,52 +1,5 @@
 <?xml version="1.0"?>
 <model xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
-  <bank bar="0" size="128" protocol="software_registers" read_address="0x9010" write_address="0x9000" word_size="8" endianess="little" format="%lu" name="cmosis" description="CMOSIS CMV2000 Registers">
-    <register address="1" offset="0" size="16" default="1088" rwmask="0" mode="RW" name="cmosis_number_lines" description="test"/>
-    <register address="3" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start1"/>
-    <register address="5" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start2"/>
-    <register address="7" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start3"/>
-    <register address="9" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start4"/>
-    <register address="11" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start5"/>
-    <register address="13" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start6"/>
-    <register address="15" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start7"/>
-    <register address="17" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start8"/>
-    <register address="19" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines1"/>
-    <register address="21" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines2"/>
-    <register address="23" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines3"/>
-    <register address="25" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines4"/>
-    <register address="27" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines5"/>
-    <register address="29" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines6"/>
-    <register address="31" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines7"/>
-    <register address="33" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines8"/>
-    <register address="35" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_sub_s"/>
-    <register address="37" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_sub_a"/>
-    <register address="39" offset="0" size="1" default="1" rwmask="0" mode="RW" name="cmosis_color"/>
-    <register address="40" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_image_flipping"/>
-    <register address="41" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_exp_flags"/>
-    <register address="42" offset="0" size="24" default="1088" rwmask="0" mode="RW" name="cmosis_exp_time"><view view="formuu3"/><view view="enumm3"/></register>
-    <register address="45" offset="0" size="24" default="1088" rwmask="0" mode="RW" name="cmosis_exp_step"/>
-    <register address="48" offset="0" size="24" default="1" rwmask="0" mode="RW" name="cmosis_exp_kp1"/>
-    <register address="51" offset="0" size="24" default="1" rwmask="0" mode="RW" name="cmosis_exp_kp2"/>
-    <register address="54" offset="0" size="2" default="1" rwmask="0" mode="RW" name="cmosis_nr_slopes"/>
-    <register address="55" offset="0" size="8" default="1" rwmask="0" mode="RW" name="cmosis_exp_seq"/>
-    <register address="56" offset="0" size="24" default="1088" rwmask="0" mode="RW" name="cmosis_exp_time2"/>
-    <register address="59" offset="0" size="24" default="1088" rwmask="0" mode="RW" name="cmosis_exp_step2"/>
-    <register address="68" offset="0" size="2" default="1" rwmask="0" mode="RW" name="cmosis_nr_slopes2"/>
-    <register address="69" offset="0" size="8" default="1" rwmask="0" mode="RW" name="cmosis_exp_seq2"/>
-    <register address="70" offset="0" size="16" default="1" rwmask="0" mode="RW" name="cmosis_number_frames"/>
-    <register address="72" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_output_mode"/>
-    <register address="78" offset="0" size="12" default="85" rwmask="0" mode="RW" name="cmosis_training_pattern"/>
-    <register address="80" offset="0" size="18" default="0x3FFFF" rwmask="0" mode="RW" name="cmosis_channel_en"/>
-    <register address="82" offset="0" size="3" default="7" rwmask="0" mode="RW" name="cmosis_special_82"/>
-    <register address="89" offset="0" size="8" default="96" rwmask="0" mode="RW" name="cmosis_vlow2"/>
-    <register address="90" offset="0" size="8" default="96" rwmask="0" mode="RW" name="cmosis_vlow3"/>
-    <register address="100" offset="0" size="14" default="16260" rwmask="0" mode="RW" name="cmosis_offset"/>
-    <register address="102" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_pga"/>
-    <register address="103" offset="0" size="8" default="32" rwmask="0" mode="RW" name="cmosis_adc_gain"/>
-    <register address="111" offset="0" size="1" default="1" rwmask="0" mode="RW" name="cmosis_bit_mode"/>
-    <register address="112" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_adc_resolution"/>
-    <register address="115" offset="0" size="1" default="1" rwmask="0" mode="RW" name="cmosis_special_115"/>
-  </bank>
   <bank bar="0" size="0x0200" protocol="software_registers" read_address="0x9000" write_address="0x9000" word_size="32" endianess="little" format="0x%lx" name="fpga" description="IPECamera Registers">
     <register address="0x00" offset="0" size="32" default="0" rwmask="0" mode="RW" name="spi_conf_input"/>
     <register address="0x10" offset="0" size="32" default="0" rwmask="0" mode="R" name="spi_conf_output"/>
@@ -105,54 +58,4 @@
     <register address="0x1a0" offset="0" size="32" default="0x64" rwmask="0" mode="RW" name="ddr_max_frames"/>
     <register address="0x1b0" offset="0" size="32" default="0" rwmask="0" mode="R" name="ddr_num_frames"/>
   </bank>
-  <bank bar="0" size="0x0200" protocol="software_registers" read_address="0x0" write_address="0x0" word_size="32" endianess="little" format="0x%lx" name="dma" description="DMA Registers"/>
-  <transform path="/test/prop1" register="test_prop1" unit="C" read_from_register="(503975./1024000)*${/registers/fpga/sensor_temperature:C} - 27315./100" description="formula to get real fpga temperature from the fpga_temperature register in decimal"/>
-  <transform name="formuu1" unit="C" read_from_register="(503975./1024000)*$value - 27315./100" write_to_register="($value + 27315./100)*(1024000./503975)" description="formula to get real fpga temperature from the fpga_temperature register in decimal"/>
-  <transform name="formuu2" unit="C1" read_from_register="((1./4)*($value - 1200)) if $freq==0 else ((3./10)*($value - 1000))" write_to_register="4*$value + 1200 if $freq==0 else (10./3)*$value + 1000" description="formula to get real sensor temperature from the sensor_temperature register in decimal"/>
-  <transform name="formuu3" unit="us" read_from_register="($value+(43./100))*129./(40*1000000)if $freq==0 else ($value+(43./100))*129./(48*1000000)" write_to_register="$value/129.*(40*1000000) - 43./100 if $freq==0 else $value/129.*(48*1000000) - 43./100" description="formula to get real exposure time from the cmosis_exp_time register in decimal"/>
-  <enum name="enumm1" description="enum towards temperatures register">
-    <name name="high" value="0x100" min="0x2" max="0x300"/>
-    <name name="low" value="0x010"/>
-  </enum>
-  <enum name="enumm2" description="enum towards sensor_temperature register">
-    <name name="high" value="0x120"/>
-    <name name="low" value="0x010" min="0x00" max="0x020"/>
-  </enum>
-  <enum name="enumm3" description="enum towards cmosis_exp_register register">
-    <name name="short" value="0x000"/>
-    <name name="mid" value="0x010"/>
-    <name name="long" value="0x100" min="0x0F0"/>
-  </enum>
-  <unit name="C">
-    <transform unit="K" transform="$value+273.15"/>
-    <transform unit="F" transform="$value*(9./5)+32"/>
-  </unit>
-  <unit name="K">
-    <transform unit="C" transform="$value-273.15"/>
-    <transform unit="F" transform="($value-273.15)*(9./5)+32"/>
-  </unit>
-  <unit name="F">
-    <transform unit="C" transform="($value-32)*5./9"/>
-    <transform unit="K" transform="($value+273.15-32)*5./9"/>
-  </unit>
-  <unit name="s">
-    <transform unit="ms" transform="$value*1000"/>
-    <transform unit="us" transform="$value*1000000"/>
-    <transform unit="ns" transform="$value*1000000000"/>
-  </unit>
-  <unit name="ms">
-    <transform unit="s" transform="$value/1000"/>
-    <transform unit="us" transform="$value*1000"/>
-    <transform unit="ns" transform="$value*1000000"/>
-  </unit>
-  <unit name="us">
-    <transform unit="s" transform="$value/1000000"/>
-    <transform unit="ms" transform="$value/1000"/>
-    <transform unit="ns" transform="$value*1000"/>
-  </unit>
-  <unit name="ns">
-    <transform unit="s" transform="$value/1000000000"/>
-    <transform unit="ms" transform="$value/1000000"/>
-    <transform unit="us" transform="$value/1000"/>
-  </unit>
 </model>
diff --git a/xml/test/cmosis.xml b/xml/test/cmosis.xml
new file mode 100644
index 0000000..45d2f6e
--- /dev/null
+++ b/xml/test/cmosis.xml
@@ -0,0 +1,50 @@
+<?xml version="1.0"?>
+<model xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <bank bar="0" size="128" protocol="software_registers" read_address="0x9010" write_address="0x9000" word_size="8" endianess="little" format="%lu" name="cmosis" description="CMOSIS CMV2000 Registers">
+    <register address="1" offset="0" size="16" default="1088" rwmask="0" mode="RW" name="cmosis_number_lines" description="test"/>
+    <register address="3" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start1"/>
+    <register address="5" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start2"/>
+    <register address="7" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start3"/>
+    <register address="9" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start4"/>
+    <register address="11" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start5"/>
+    <register address="13" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start6"/>
+    <register address="15" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start7"/>
+    <register address="17" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_start8"/>
+    <register address="19" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines1"/>
+    <register address="21" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines2"/>
+    <register address="23" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines3"/>
+    <register address="25" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines4"/>
+    <register address="27" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines5"/>
+    <register address="29" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines6"/>
+    <register address="31" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines7"/>
+    <register address="33" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_number_lines8"/>
+    <register address="35" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_sub_s"/>
+    <register address="37" offset="0" size="16" default="0" rwmask="0" mode="RW" name="cmosis_sub_a"/>
+    <register address="39" offset="0" size="1" default="1" rwmask="0" mode="RW" name="cmosis_color"/>
+    <register address="40" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_image_flipping"/>
+    <register address="41" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_exp_flags"/>
+    <register address="42" offset="0" size="24" default="1088" rwmask="0" mode="RW" name="cmosis_exp_time"><view view="formuu3"/><view view="enumm3"/></register>
+    <register address="45" offset="0" size="24" default="1088" rwmask="0" mode="RW" name="cmosis_exp_step"/>
+    <register address="48" offset="0" size="24" default="1" rwmask="0" mode="RW" name="cmosis_exp_kp1"/>
+    <register address="51" offset="0" size="24" default="1" rwmask="0" mode="RW" name="cmosis_exp_kp2"/>
+    <register address="54" offset="0" size="2" default="1" rwmask="0" mode="RW" name="cmosis_nr_slopes"/>
+    <register address="55" offset="0" size="8" default="1" rwmask="0" mode="RW" name="cmosis_exp_seq"/>
+    <register address="56" offset="0" size="24" default="1088" rwmask="0" mode="RW" name="cmosis_exp_time2"/>
+    <register address="59" offset="0" size="24" default="1088" rwmask="0" mode="RW" name="cmosis_exp_step2"/>
+    <register address="68" offset="0" size="2" default="1" rwmask="0" mode="RW" name="cmosis_nr_slopes2"/>
+    <register address="69" offset="0" size="8" default="1" rwmask="0" mode="RW" name="cmosis_exp_seq2"/>
+    <register address="70" offset="0" size="16" default="1" rwmask="0" mode="RW" name="cmosis_number_frames"/>
+    <register address="72" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_output_mode"/>
+    <register address="78" offset="0" size="12" default="85" rwmask="0" mode="RW" name="cmosis_training_pattern"/>
+    <register address="80" offset="0" size="18" default="0x3FFFF" rwmask="0" mode="RW" name="cmosis_channel_en"/>
+    <register address="82" offset="0" size="3" default="7" rwmask="0" mode="RW" name="cmosis_special_82"/>
+    <register address="89" offset="0" size="8" default="96" rwmask="0" mode="RW" name="cmosis_vlow2"/>
+    <register address="90" offset="0" size="8" default="96" rwmask="0" mode="RW" name="cmosis_vlow3"/>
+    <register address="100" offset="0" size="14" default="16260" rwmask="0" mode="RW" name="cmosis_offset"/>
+    <register address="102" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_pga"/>
+    <register address="103" offset="0" size="8" default="32" rwmask="0" mode="RW" name="cmosis_adc_gain"/>
+    <register address="111" offset="0" size="1" default="1" rwmask="0" mode="RW" name="cmosis_bit_mode"/>
+    <register address="112" offset="0" size="2" default="0" rwmask="0" mode="RW" name="cmosis_adc_resolution"/>
+    <register address="115" offset="0" size="1" default="1" rwmask="0" mode="RW" name="cmosis_special_115"/>
+  </bank>
+</model>
diff --git a/xml/test/dma.xml b/xml/test/dma.xml
new file mode 100644
index 0000000..1d20725
--- /dev/null
+++ b/xml/test/dma.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0"?>
+<model xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <bank bar="0" size="0x0200" protocol="software_registers" read_address="0x0" write_address="0x0" word_size="32" endianess="little" format="0x%lx" name="dma" description="DMA Registers"/>
+</model>
diff --git a/xml/test/names.xml b/xml/test/names.xml
new file mode 100644
index 0000000..f6ddbcc
--- /dev/null
+++ b/xml/test/names.xml
@@ -0,0 +1,16 @@
+<?xml version="1.0"?>
+<model xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <enum name="enumm1" description="enum towards temperatures register">
+    <name name="high" value="0x100" min="0x2" max="0x300"/>
+    <name name="low" value="0x010"/>
+  </enum>
+  <enum name="enumm2" description="enum towards sensor_temperature register">
+    <name name="high" value="0x120"/>
+    <name name="low" value="0x010" min="0x00" max="0x020"/>
+  </enum>
+  <enum name="enumm3" description="enum towards cmosis_exp_register register">
+    <name name="short" value="0x000"/>
+    <name name="mid" value="0x010"/>
+    <name name="long" value="0x100" min="0x0F0"/>
+  </enum>
+</model>
diff --git a/xml/test/props.xml b/xml/test/props.xml
new file mode 100644
index 0000000..cf163eb
--- /dev/null
+++ b/xml/test/props.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0"?>
+<model xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <transform path="/test/prop1" register="test_prop1" unit="C" read_from_register="(503975./1024000)*${/registers/fpga/sensor_temperature:C} - 27315./100" description="formula to get real fpga temperature from the fpga_temperature register in decimal"/>
+</model>
diff --git a/xml/test/units.xml b/xml/test/units.xml
new file mode 100644
index 0000000..74ab9f7
--- /dev/null
+++ b/xml/test/units.xml
@@ -0,0 +1,35 @@
+<?xml version="1.0"?>
+<model xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <unit name="C">
+    <transform unit="K" transform="$value+273.15"/>
+    <transform unit="F" transform="$value*(9./5)+32"/>
+  </unit>
+  <unit name="K">
+    <transform unit="C" transform="$value-273.15"/>
+    <transform unit="F" transform="($value-273.15)*(9./5)+32"/>
+  </unit>
+  <unit name="F">
+    <transform unit="C" transform="($value-32)*5./9"/>
+    <transform unit="K" transform="($value+273.15-32)*5./9"/>
+  </unit>
+  <unit name="s">
+    <transform unit="ms" transform="$value*1000"/>
+    <transform unit="us" transform="$value*1000000"/>
+    <transform unit="ns" transform="$value*1000000000"/>
+  </unit>
+  <unit name="ms">
+    <transform unit="s" transform="$value/1000"/>
+    <transform unit="us" transform="$value*1000"/>
+    <transform unit="ns" transform="$value*1000000"/>
+  </unit>
+  <unit name="us">
+    <transform unit="s" transform="$value/1000000"/>
+    <transform unit="ms" transform="$value/1000"/>
+    <transform unit="ns" transform="$value*1000"/>
+  </unit>
+  <unit name="ns">
+    <transform unit="s" transform="$value/1000000000"/>
+    <transform unit="ms" transform="$value/1000000"/>
+    <transform unit="us" transform="$value/1000"/>
+  </unit>
+</model>
diff --git a/xml/test/views.xml b/xml/test/views.xml
new file mode 100644
index 0000000..c40cd0f
--- /dev/null
+++ b/xml/test/views.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0"?>
+<model xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <transform name="formuu1" unit="C" read_from_register="(503975./1024000)*$value - 27315./100" write_to_register="($value + 27315./100)*(1024000./503975)" description="formula to get real fpga temperature from the fpga_temperature register in decimal"/>
+  <transform name="formuu2" unit="C1" read_from_register="((1./4)*($value - 1200)) if $freq==0 else ((3./10)*($value - 1000))" write_to_register="4*$value + 1200 if $freq==0 else (10./3)*$value + 1000" description="formula to get real sensor temperature from the sensor_temperature register in decimal"/>
+  <transform name="formuu3" unit="us" read_from_register="($value+(43./100))*129./(40*1000000)if $freq==0 else ($value+(43./100))*129./(48*1000000)" write_to_register="$value/129.*(40*1000000) - 43./100 if $freq==0 else $value/129.*(48*1000000) - 43./100" description="formula to get real exposure time from the cmosis_exp_time register in decimal"/>
+</model>