From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Wed, 7 Feb 2007 16:37:50 +1100 From: David Gibson To: Kumar Gala Subject: Re: [dtc] Allow multipart property values Message-ID: <20070207053750.GG23870@localhost.localdomain> References: <20070207032343.GD23870@localhost.localdomain> <41B393C3-9A8F-46EC-9B47-FCF8E0733994@kernel.crashing.org> <20070207044616.GF23870@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, Feb 06, 2007 at 10:50:09PM -0600, Kumar Gala wrote: > > On Feb 6, 2007, at 10:46 PM, David Gibson wrote: > > > On Tue, Feb 06, 2007 at 10:37:25PM -0600, Kumar Gala wrote: > >> > >> On Feb 6, 2007, at 9:23 PM, David Gibson wrote: > >> > >>> At present each property definition in a dts file must give as the > >>> value either a string ("abc..."), a bytestring ([12abcd...]) or a > >>> cell > >>> list (<1 2 3 ...>). This patch allows a property value to be > >>> given as > >>> several of these, comma-separated. The final property value is just > >>> the components appended together. So a property could have a > >>> list of > >>> cells followed by a string, or a bytestring followed by some cells. > >>> Cells are always aligned, so if cells are given following a > >>> string or > >>> bytestring which is not a multiple of 4 bytes long, zero bytes are > >>> inserted to align the following cells. > >>> > >>> The primary motivation for this feature, however, is to allow > >>> defining > >>> a property as a list of several strings. This is what's needed for > >>> defining OF 'compatible' properties, and is less ugly and fiddly > >>> than > >>> using embedded \0s in the strings. > >>> > >>> Signed-off-by: David Gibson > >> > >> Mind adding examples to the testsuite? > > > > What testsuite...? > > Well there was a tests/ dir and test.dts :) There's nothing in tests/ though - I always meant to make a testsuite, but I never got around to it. Current plan is to implement a testsuite by merging libfdt into the dtc tree. Here's a revised patch which adds an example usage to test.dts [dtc] Allow multipart property values At present each property definition in a dts file must give as the value either a string ("abc..."), a bytestring ([12abcd...]) or a cell list (<1 2 3 ...>). This patch allows a property value to be given as several of these, comma-separated. The final property value is just the components appended together. So a property could have a list of cells followed by a string, or a bytestring followed by some cells. Cells are always aligned, so if cells are given following a string or bytestring which is not a multiple of 4 bytes long, zero bytes are inserted to align the following cells. The primary motivation for this feature, however, is to allow defining a property as a list of several strings. This is what's needed for defining OF 'compatible' properties, and is less ugly and fiddly than using embedded \0s in the strings. Signed-off-by: David Gibson Index: dtc/data.c =================================================================== --- dtc.orig/data.c 2007-02-07 14:17:00.000000000 +1100 +++ dtc/data.c 2007-02-07 14:24:34.000000000 +1100 @@ -197,6 +197,33 @@ struct data data_append_data(struct data return d; } +struct data data_merge(struct data d1, struct data d2) +{ + struct data d; + struct fixup **ff; + struct fixup *f, *f2; + + d = data_append_data(d1, d2.val, d2.len); + + /* Extract d2's fixups */ + f2 = d2.refs; + d2.refs = NULL; + + /* Tack them onto d's list of fixups */ + ff = &d.refs; + while (*ff) + ff = &((*ff)->next); + *ff = f2; + + /* And correct them for their new position */ + for (f = f2; f; f = f->next) + f->offset += d1.len; + + data_free(d2); + + return d; +} + struct data data_append_cell(struct data d, cell_t word) { cell_t beword = cpu_to_be32(word); Index: dtc/dtc-parser.y =================================================================== --- dtc.orig/dtc-parser.y 2007-02-07 14:17:00.000000000 +1100 +++ dtc/dtc-parser.y 2007-02-07 14:24:34.000000000 +1100 @@ -58,6 +58,7 @@ extern struct boot_info *the_boot_info; %token DT_REF %type propdata +%type propdataprefix %type memreserve %type memreserves %type celllist @@ -121,9 +122,15 @@ propdef: label DT_PROPNAME '=' propdata } ; -propdata: DT_STRING { $$ = $1; } - | '<' celllist '>' { $$ = $2; } - | '[' bytestring ']' { $$ = $2; } +propdata: propdataprefix DT_STRING { $$ = data_merge($1, $2); } + | propdataprefix '<' celllist '>' { + $$ = data_merge(data_append_align($1, sizeof(cell_t)), $3); + } + | propdataprefix '[' bytestring ']' { $$ = data_merge($1, $3); } + ; + +propdataprefix: propdata ',' { $$ = $1; } + | /* empty */ { $$ = empty_data; } ; celllist: celllist DT_CELL { $$ = data_append_cell($1, $2); } Index: dtc/dtc.h =================================================================== --- dtc.orig/dtc.h 2007-02-07 14:17:00.000000000 +1100 +++ dtc/dtc.h 2007-02-07 14:24:34.000000000 +1100 @@ -119,6 +119,7 @@ struct data data_copy_escape_string(char struct data data_copy_file(FILE *f, size_t len); struct data data_append_data(struct data d, void *p, int len); +struct data data_merge(struct data d1, struct data d2); struct data data_append_cell(struct data d, cell_t word); struct data data_append_re(struct data d, struct reserve_entry *re); struct data data_append_addr(struct data d, u64 addr); Index: dtc/dtc-lexer.l =================================================================== --- dtc.orig/dtc-lexer.l 2007-02-07 14:17:00.000000000 +1100 +++ dtc/dtc-lexer.l 2007-02-07 14:24:34.000000000 +1100 @@ -123,6 +123,15 @@ REFCHAR ({PROPCHAR}|{UNITCHAR}|[/@]) return ']'; } +, { /* Technically this is a valid property name, + but we'd rather use it as punctuation, so detect it + here in preference */ + yylloc.first_line = yylineno; + DPRINT("Char (propname like): %c (\\x%02x)\n", yytext[0], + (unsigned)yytext[0]); + return yytext[0]; + } + {PROPCHAR}+ { yylloc.first_line = yylineno; DPRINT("PropName: %s\n", yytext); Index: dtc/test.dts =================================================================== --- dtc.orig/test.dts 2007-02-07 16:35:54.000000000 +1100 +++ dtc/test.dts 2007-02-07 16:37:21.000000000 +1100 @@ -4,7 +4,7 @@ / { model = "MyBoardName"; - compatible = "MyBoardFamilyName"; + compatible = "MyBoardName", "MyBoardFamilyName"; #address-cells = <2>; #size-cells = <2>; @@ -39,6 +39,7 @@ string = "\xff\0stuffstuff\t\t\t\n\n\n"; blob = [0a 0b 0c 0d de ea ad be ef]; ref = < &/memory@0 >; + mixed = "abc", [1234], ; }; memory@0 { -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson