u-boot/scripts/dtc/dtc-parser.y
Maxime Ripard 5ed2dc5623 dtc: add ability to make nodes conditional on them being referenced
This is needed when importing mainline DTs into U-Boot, as some started
using this /omit-if-no-ref/ tag, so won't compile with U-Boot's current
dtc copy. This is just a cherry-pick of the patch introducing this
feature.
Original commit message from Maxime:
------------------
A number of platforms have a need to reduce the number of DT nodes,
mostly because of two similar constraints: the size of the DT blob, and
the time it takes to parse it.

As the DT is used in more and more SoCs, and by more projects, some
constraints start to appear in bootloaders running from SRAM with an
order of magnitude of 10kB. A typical DT is in the same order of
magnitude, so any effort to reduce the blob size is welcome in such an
environment.

Some platforms also want to reach very fast boot time, and the time it
takes to parse a typical DT starts to be noticeable.

Both of these issues can be mitigated by reducing the number of nodes in
the DT. The biggest provider of nodes is usually the pin controller and
its subnodes, usually one for each valid pin configuration in a given
SoC.

Obviously, a single, fixed, set of these nodes will be used by a given
board, so we can introduce a node property that will tell the DT
compiler to drop the nodes when they are not referenced in the tree, and
as such wouldn't be useful in the targetted system.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2020-02-05 19:33:46 -07:00

555 lines
10 KiB
Text

/*
* (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation. 2005.
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*/
%{
#include <stdio.h>
#include <inttypes.h>
#include "dtc.h"
#include "srcpos.h"
extern int yylex(void);
extern void yyerror(char const *s);
#define ERROR(loc, ...) \
do { \
srcpos_error((loc), "Error", __VA_ARGS__); \
treesource_error = true; \
} while (0)
extern struct dt_info *parser_output;
extern bool treesource_error;
%}
%union {
char *propnodename;
char *labelref;
uint8_t byte;
struct data data;
struct {
struct data data;
int bits;
} array;
struct property *prop;
struct property *proplist;
struct node *node;
struct node *nodelist;
struct reserve_info *re;
uint64_t integer;
unsigned int flags;
}
%token DT_V1
%token DT_PLUGIN
%token DT_MEMRESERVE
%token DT_LSHIFT DT_RSHIFT DT_LE DT_GE DT_EQ DT_NE DT_AND DT_OR
%token DT_BITS
%token DT_DEL_PROP
%token DT_DEL_NODE
%token DT_OMIT_NO_REF
%token <propnodename> DT_PROPNODENAME
%token <integer> DT_LITERAL
%token <integer> DT_CHAR_LITERAL
%token <byte> DT_BYTE
%token <data> DT_STRING
%token <labelref> DT_LABEL
%token <labelref> DT_REF
%token DT_INCBIN
%type <data> propdata
%type <data> propdataprefix
%type <flags> header
%type <flags> headers
%type <re> memreserve
%type <re> memreserves
%type <array> arrayprefix
%type <data> bytestring
%type <prop> propdef
%type <proplist> proplist
%type <node> devicetree
%type <node> nodedef
%type <node> subnode
%type <nodelist> subnodes
%type <integer> integer_prim
%type <integer> integer_unary
%type <integer> integer_mul
%type <integer> integer_add
%type <integer> integer_shift
%type <integer> integer_rela
%type <integer> integer_eq
%type <integer> integer_bitand
%type <integer> integer_bitxor
%type <integer> integer_bitor
%type <integer> integer_and
%type <integer> integer_or
%type <integer> integer_trinary
%type <integer> integer_expr
%%
sourcefile:
headers memreserves devicetree
{
parser_output = build_dt_info($1, $2, $3,
guess_boot_cpuid($3));
}
;
header:
DT_V1 ';'
{
$$ = DTSF_V1;
}
| DT_V1 ';' DT_PLUGIN ';'
{
$$ = DTSF_V1 | DTSF_PLUGIN;
}
;
headers:
header
| header headers
{
if ($2 != $1)
ERROR(&@2, "Header flags don't match earlier ones");
$$ = $1;
}
;
memreserves:
/* empty */
{
$$ = NULL;
}
| memreserve memreserves
{
$$ = chain_reserve_entry($1, $2);
}
;
memreserve:
DT_MEMRESERVE integer_prim integer_prim ';'
{
$$ = build_reserve_entry($2, $3);
}
| DT_LABEL memreserve
{
add_label(&$2->labels, $1);
$$ = $2;
}
;
devicetree:
'/' nodedef
{
$$ = name_node($2, "");
}
| devicetree '/' nodedef
{
$$ = merge_nodes($1, $3);
}
| DT_REF nodedef
{
/*
* We rely on the rule being always:
* versioninfo plugindecl memreserves devicetree
* so $-1 is what we want (plugindecl)
*/
if (!($<flags>-1 & DTSF_PLUGIN))
ERROR(&@2, "Label or path %s not found", $1);
$$ = add_orphan_node(name_node(build_node(NULL, NULL), ""), $2, $1);
}
| devicetree DT_LABEL DT_REF nodedef
{
struct node *target = get_node_by_ref($1, $3);
if (target) {
add_label(&target->labels, $2);
merge_nodes(target, $4);
} else
ERROR(&@3, "Label or path %s not found", $3);
$$ = $1;
}
| devicetree DT_REF nodedef
{
struct node *target = get_node_by_ref($1, $2);
if (target) {
merge_nodes(target, $3);
} else {
/*
* We rely on the rule being always:
* versioninfo plugindecl memreserves devicetree
* so $-1 is what we want (plugindecl)
*/
if ($<flags>-1 & DTSF_PLUGIN)
add_orphan_node($1, $3, $2);
else
ERROR(&@2, "Label or path %s not found", $2);
}
$$ = $1;
}
| devicetree DT_DEL_NODE DT_REF ';'
{
struct node *target = get_node_by_ref($1, $3);
if (target)
delete_node(target);
else
ERROR(&@3, "Label or path %s not found", $3);
$$ = $1;
}
| devicetree DT_OMIT_NO_REF DT_REF ';'
{
struct node *target = get_node_by_ref($1, $3);
if (target)
omit_node_if_unused(target);
else
ERROR(&@3, "Label or path %s not found", $3);
$$ = $1;
}
;
nodedef:
'{' proplist subnodes '}' ';'
{
$$ = build_node($2, $3);
}
;
proplist:
/* empty */
{
$$ = NULL;
}
| proplist propdef
{
$$ = chain_property($2, $1);
}
;
propdef:
DT_PROPNODENAME '=' propdata ';'
{
$$ = build_property($1, $3);
}
| DT_PROPNODENAME ';'
{
$$ = build_property($1, empty_data);
}
| DT_DEL_PROP DT_PROPNODENAME ';'
{
$$ = build_property_delete($2);
}
| DT_LABEL propdef
{
add_label(&$2->labels, $1);
$$ = $2;
}
;
propdata:
propdataprefix DT_STRING
{
$$ = data_merge($1, $2);
}
| propdataprefix arrayprefix '>'
{
$$ = data_merge($1, $2.data);
}
| propdataprefix '[' bytestring ']'
{
$$ = data_merge($1, $3);
}
| propdataprefix DT_REF
{
$$ = data_add_marker($1, REF_PATH, $2);
}
| propdataprefix DT_INCBIN '(' DT_STRING ',' integer_prim ',' integer_prim ')'
{
FILE *f = srcfile_relative_open($4.val, NULL);
struct data d;
if ($6 != 0)
if (fseek(f, $6, SEEK_SET) != 0)
die("Couldn't seek to offset %llu in \"%s\": %s",
(unsigned long long)$6, $4.val,
strerror(errno));
d = data_copy_file(f, $8);
$$ = data_merge($1, d);
fclose(f);
}
| propdataprefix DT_INCBIN '(' DT_STRING ')'
{
FILE *f = srcfile_relative_open($4.val, NULL);
struct data d = empty_data;
d = data_copy_file(f, -1);
$$ = data_merge($1, d);
fclose(f);
}
| propdata DT_LABEL
{
$$ = data_add_marker($1, LABEL, $2);
}
;
propdataprefix:
/* empty */
{
$$ = empty_data;
}
| propdata ','
{
$$ = $1;
}
| propdataprefix DT_LABEL
{
$$ = data_add_marker($1, LABEL, $2);
}
;
arrayprefix:
DT_BITS DT_LITERAL '<'
{
unsigned long long bits;
bits = $2;
if ((bits != 8) && (bits != 16) &&
(bits != 32) && (bits != 64)) {
ERROR(&@2, "Array elements must be"
" 8, 16, 32 or 64-bits");
bits = 32;
}
$$.data = empty_data;
$$.bits = bits;
}
| '<'
{
$$.data = empty_data;
$$.bits = 32;
}
| arrayprefix integer_prim
{
if ($1.bits < 64) {
uint64_t mask = (1ULL << $1.bits) - 1;
/*
* Bits above mask must either be all zero
* (positive within range of mask) or all one
* (negative and sign-extended). The second
* condition is true if when we set all bits
* within the mask to one (i.e. | in the
* mask), all bits are one.
*/
if (($2 > mask) && (($2 | mask) != -1ULL))
ERROR(&@2, "Value out of range for"
" %d-bit array element", $1.bits);
}
$$.data = data_append_integer($1.data, $2, $1.bits);
}
| arrayprefix DT_REF
{
uint64_t val = ~0ULL >> (64 - $1.bits);
if ($1.bits == 32)
$1.data = data_add_marker($1.data,
REF_PHANDLE,
$2);
else
ERROR(&@2, "References are only allowed in "
"arrays with 32-bit elements.");
$$.data = data_append_integer($1.data, val, $1.bits);
}
| arrayprefix DT_LABEL
{
$$.data = data_add_marker($1.data, LABEL, $2);
}
;
integer_prim:
DT_LITERAL
| DT_CHAR_LITERAL
| '(' integer_expr ')'
{
$$ = $2;
}
;
integer_expr:
integer_trinary
;
integer_trinary:
integer_or
| integer_or '?' integer_expr ':' integer_trinary { $$ = $1 ? $3 : $5; }
;
integer_or:
integer_and
| integer_or DT_OR integer_and { $$ = $1 || $3; }
;
integer_and:
integer_bitor
| integer_and DT_AND integer_bitor { $$ = $1 && $3; }
;
integer_bitor:
integer_bitxor
| integer_bitor '|' integer_bitxor { $$ = $1 | $3; }
;
integer_bitxor:
integer_bitand
| integer_bitxor '^' integer_bitand { $$ = $1 ^ $3; }
;
integer_bitand:
integer_eq
| integer_bitand '&' integer_eq { $$ = $1 & $3; }
;
integer_eq:
integer_rela
| integer_eq DT_EQ integer_rela { $$ = $1 == $3; }
| integer_eq DT_NE integer_rela { $$ = $1 != $3; }
;
integer_rela:
integer_shift
| integer_rela '<' integer_shift { $$ = $1 < $3; }
| integer_rela '>' integer_shift { $$ = $1 > $3; }
| integer_rela DT_LE integer_shift { $$ = $1 <= $3; }
| integer_rela DT_GE integer_shift { $$ = $1 >= $3; }
;
integer_shift:
integer_shift DT_LSHIFT integer_add { $$ = $1 << $3; }
| integer_shift DT_RSHIFT integer_add { $$ = $1 >> $3; }
| integer_add
;
integer_add:
integer_add '+' integer_mul { $$ = $1 + $3; }
| integer_add '-' integer_mul { $$ = $1 - $3; }
| integer_mul
;
integer_mul:
integer_mul '*' integer_unary { $$ = $1 * $3; }
| integer_mul '/' integer_unary
{
if ($3 != 0) {
$$ = $1 / $3;
} else {
ERROR(&@$, "Division by zero");
$$ = 0;
}
}
| integer_mul '%' integer_unary
{
if ($3 != 0) {
$$ = $1 % $3;
} else {
ERROR(&@$, "Division by zero");
$$ = 0;
}
}
| integer_unary
;
integer_unary:
integer_prim
| '-' integer_unary { $$ = -$2; }
| '~' integer_unary { $$ = ~$2; }
| '!' integer_unary { $$ = !$2; }
;
bytestring:
/* empty */
{
$$ = empty_data;
}
| bytestring DT_BYTE
{
$$ = data_append_byte($1, $2);
}
| bytestring DT_LABEL
{
$$ = data_add_marker($1, LABEL, $2);
}
;
subnodes:
/* empty */
{
$$ = NULL;
}
| subnode subnodes
{
$$ = chain_node($1, $2);
}
| subnode propdef
{
ERROR(&@2, "Properties must precede subnodes");
YYERROR;
}
;
subnode:
DT_PROPNODENAME nodedef
{
$$ = name_node($2, $1);
}
| DT_DEL_NODE DT_PROPNODENAME ';'
{
$$ = name_node(build_node_delete(), $2);
}
| DT_OMIT_NO_REF subnode
{
$$ = omit_node_if_unused($2);
}
| DT_LABEL subnode
{
add_label(&$2->labels, $1);
$$ = $2;
}
;
%%
void yyerror(char const *s)
{
ERROR(&yylloc, "%s", s);
}