From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: [RFC PATCH] dtc: Add support for named constants Date: Tue, 23 Aug 2011 16:43:20 -0600 Message-ID: <1314139400-31984-1-git-send-email-swarren@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org To: David Gibson , jdl-CYoMK+44s/E@public.gmane.org Cc: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, Arnaud Lacombe List-Id: devicetree@vger.kernel.org You may define constants as follows: /define/ $TWO 2; /define/ $FOUR 4; /define/ $OTHER $FOUR; And properties may use these values as follows: foo = <1 $TWO 3 $FOUR 5>; Signed-off-by: Stephen Warren --- Note 1: This is against dtc in the Linux kernel. Should this patch be against upstream dtc, then back-ported to the kernel? Note 2: I'd prefer the syntax of /define/ to be: /define/ TWO 2; but I assume that'd cause the lexing for DT_DEFINEREF to conflict with that for DT_LABEL? Note 3: The define syntax only handles integers. Should it be string- based instead? Note 4: I'm not sure what to do about re-generating the lex/yacc results; my local tools aren't the versions used previously, and so introduce some changes not related to mine. scripts/dtc/dtc-lexer.l | 12 ++++++ scripts/dtc/dtc-parser.y | 98 +++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 109 insertions(+), 1 deletions(-) diff --git a/scripts/dtc/dtc-lexer.l b/scripts/dtc/dtc-lexer.l index e866ea5..ff31bbf 100644 --- a/scripts/dtc/dtc-lexer.l +++ b/scripts/dtc/dtc-lexer.l @@ -96,6 +96,12 @@ static int pop_input_file(void); return DT_MEMRESERVE; } +<*>"/define/" { + DPRINT("Keyword: /define/\n"); + BEGIN_DEFAULT(); + return DT_DEFINE; + } + <*>{LABEL}: { DPRINT("Label: %s\n", yytext); yylval.labelref = xstrdup(yytext); @@ -109,6 +115,12 @@ static int pop_input_file(void); return DT_LITERAL; } +\${LABEL} { + yylval.defineref = xstrdup(yytext + 1); + DPRINT("Define: '%s'\n", yylval.defineref); + return DT_DEFINEREF; + } + <*>\&{LABEL} { /* label reference */ DPRINT("Ref: %s\n", yytext+1); yylval.labelref = xstrdup(yytext+1); diff --git a/scripts/dtc/dtc-parser.y b/scripts/dtc/dtc-parser.y index 5e84a67..50bc10b 100644 --- a/scripts/dtc/dtc-parser.y +++ b/scripts/dtc/dtc-parser.y @@ -33,12 +33,18 @@ extern void yyerror(char const *s); extern struct boot_info *the_boot_info; extern int treesource_error; +static struct define *get_define(const char *s); +static void set_define(const char *name, unsigned long long value); +static void set_define_defineref(const char *name, const char *ref); +static void set_define_literal(const char *name, const char *value); +static unsigned long long eval_defineref(const char *s, int bits); static unsigned long long eval_literal(const char *s, int base, int bits); %} %union { char *propnodename; char *literal; + char *defineref; char *labelref; unsigned int cbase; uint8_t byte; @@ -55,8 +61,10 @@ static unsigned long long eval_literal(const char *s, int base, int bits); %token DT_V1 %token DT_MEMRESERVE +%token DT_DEFINE %token DT_PROPNODENAME %token DT_LITERAL +%token DT_DEFINEREF %token DT_BASE %token DT_BYTE %token DT_STRING @@ -118,13 +126,31 @@ addr: { $$ = eval_literal($1, 0, 64); } - ; + | DT_DEFINEREF + { + $$ = eval_defineref($1, 64); + } + ; + +define: + DT_DEFINE DT_DEFINEREF DT_LITERAL ';' + { + set_define_literal($2, $3); + } + | DT_DEFINE DT_DEFINEREF DT_DEFINEREF ';' + { + set_define_defineref($2, $3); + } + ; devicetree: '/' nodedef { $$ = name_node($2, ""); } + | define + { + } | devicetree '/' nodedef { $$ = merge_nodes($1, $3); @@ -139,6 +165,9 @@ devicetree: print_error("label or path, '%s', not found", $2); $$ = $1; } + | devicetree define + { + } ; nodedef: @@ -265,6 +294,10 @@ cellval: { $$ = eval_literal($1, 0, 32); } + | DT_DEFINEREF + { + $$ = eval_defineref($1, 32); + } ; bytestring: @@ -327,6 +360,69 @@ void yyerror(char const *s) { print_error("%s", s); } +struct define { + const char *name; + unsigned long long value; + struct define *next; +}; +static struct define *defines; + +static struct define *get_define(const char *s) +{ + struct define *define = defines; + + while (define != NULL) { + if (streq(s, define->name)) + return define; + define = define->next; + } + + return NULL; +} + +static void set_define(const char *name, unsigned long long value) +{ + struct define *define; + + if (get_define(name)) { + print_error("redefining %s", name); + return; + } + + define = xmalloc(sizeof(*define)); + define->name = name; + define->value = value; + define->next = defines; + defines = define; +} + +static void set_define_defineref(const char *name, const char *ref) +{ + unsigned long long v = eval_defineref(ref, 64); + set_define(name, v); +} + +static void set_define_literal(const char *name, const char *value) +{ + unsigned long long v = eval_literal(value, 0, 64); + set_define(name, v); +} + +unsigned long long eval_defineref(const char *s, int bits) +{ + struct define *define = get_define(s); + + if (define == NULL) { + print_error("referenced define %s does not exist", s); + return 0; + } + + if ((bits < 64) && (define->value >= (1ULL << bits))) + print_error("referenced define out of range"); + + return define->value; +} + static unsigned long long eval_literal(const char *s, int base, int bits) { unsigned long long val; -- 1.7.0.4