From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Figa Subject: Re: [PATCH 1/3] dtc: Keep type information from DTS Date: Mon, 23 Dec 2013 20:16:46 +0100 Message-ID: <1671693.Jr1CHV0T8t@amdc1227> References: <1386953352-25402-1-git-send-email-t.figa@samsung.com> <1386953352-25402-2-git-send-email-t.figa@samsung.com> <52AF41A1.3000508@wwwdotorg.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7Bit Return-path: In-reply-to: <52AF41A1.3000508-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Stephen Warren Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Jason Cooper , Rob Herring , Ian Campbell , Olof Johansson , Grant Likely , Benoit Cousson , David Gibson List-Id: devicetree@vger.kernel.org On Monday 16 of December 2013 11:08:33 Stephen Warren wrote: > On 12/13/2013 09:49 AM, Tomasz Figa wrote: > > Currently dtc loses information about data types when parsing DTS, > > because it flattens all the parsed property data into a flat stream of > > bytes. The only saved metadata is for references to other nodes inside > > cell arrays. This makes it impossible to do any checks on data types on > > livetree representation. > > > > This patch makes dtc store type information inside data struct by using > > marker infrastructure. A new type of marker is introduced that holds > > type enum as its ref member. Such markers are then inserted wherever > > data of given type starts, so information about type of each property > > data section is preserved. > > > diff --git a/dtc-parser.y b/dtc-parser.y > > > | propdataprefix DT_REF > > { > > - $$ = data_add_marker($1, REF_PATH, $2); > > + struct data d; > > + d = data_add_marker($1, TYPE, (char *)TYPE_STRING); > > + $$ = data_add_marker(d, REF_PATH, $2); > > } > > I guess here, the lexer does give us a string that's the target of the > reference, so this is correct. However, I wonder if semantically we > shouldn't call this a TYPE_REFERENCE, so we can distinguish between > references and regular strings? Hmm, a REF_PATH tag is already being added by this code, so you don't lose this information. Still, maybe it would be better to unify REF_* and TYPE tags and add TYPE_PATH and TYPE_PHANDLE types... > > > diff --git a/livetree.c b/livetree.c > > > @@ -530,16 +530,24 @@ cell_t get_node_phandle(struct node *root, struct node *node) > > node->phandle = phandle; > > > > if (!get_property(node, "linux,phandle") > > - && (phandle_format & PHANDLE_LEGACY)) > > + && (phandle_format & PHANDLE_LEGACY)) { > > + struct data d; > > + > > + d = data_add_marker(empty_data, TYPE, (char *)TYPE_ARRAY_INT32); > > Similarly here, can we encode as e.g. TYPE_PHANDLE or something like > that, so we keep the semantic information? "linux,phandle" property isn't really a phandle (as in reference by phandle), but an integer assigning phandle number for given node, so I'm not sure if TYPE_PHANDLE would be correct here. Best regards, Tomasz -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html