sconfig: Allow to link devices to other device's drivers

Rarely, the driver of one device needs to know about another device
that can be anywhere in the device hierarchy. Current applications
boil down to EEPROMs that store information that is consumed by some
code (e.g. MAC address).

The idea is to give device nodes in the `devicetree.cb` an alias that
can later be used to link it to a device driver's `config` structure.
The driver has to declare a field of type `struct device *`, e.g.

    struct some_chip_driver_config {
            DEVTREE_CONST struct device *needed_eeprom;
    };

In the devicetree, the referenced device gets an alias, e.g.

    device i2c 0x50 alias my_eeprom on end

The author of the devicetree is free to choose any alias name that
is unique in the devicetree. Later, when configuring the driver the
alias can be used to link the device with the field of a driver's
config:

    chip some/chip/driver
            use my_eeprom as needed_eeprom
    end

Override devices can add an alias if it does not exist, but cannot
change the alias for a device that already exists.

Alias names are checked for conflicts both in the base tree and in the
override tree.

References are resolved after the tree is parsed so aliases and
references do not need to be in a specific order in the tree.

Change-Id: I058a319f9b968924fbef9485a96c9e3f900a3ee8
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/35456
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

7 files changed, 530 insertions, 377 deletions

diff --git a/util/sconfig/lex.yy.c_shipped b/util/sconfig/lex.yy.c_shipped
index 998505e69b..fcf5c3ed4f 100644
--- a/util/sconfig/lex.yy.c_shipped
+++ b/util/sconfig/lex.yy.c_shipped
@@ -349,8 +349,8 @@ static void yynoreturn yy_fatal_error ( const char* msg  );
 	(yy_hold_char) = *yy_cp; \
 	*yy_cp = '\0'; \
 	(yy_c_buf_p) = yy_cp;
-#define YY_NUM_RULES 45
-#define YY_END_OF_BUFFER 46
+#define YY_NUM_RULES 48
+#define YY_END_OF_BUFFER 49
 /* This struct is not used in this scanner,
    but its presence is necessary. */
 struct yy_trans_info
@@ -358,30 +358,31 @@ struct yy_trans_info
 	flex_int32_t yy_verify;
 	flex_int32_t yy_nxt;
 	};
-static const flex_int16_t yy_accept[195] =
+static const flex_int16_t yy_accept[202] =
     {   0,
-        0,    0,   46,   44,    1,    3,   44,   44,   44,   39,
-       39,   37,   40,   44,   40,   40,   40,   40,   44,   44,
-       44,   44,   44,   44,   44,   44,   44,   44,   44,    1,
-        3,   44,    0,   44,   44,    0,    2,   39,   40,   44,
-       44,   44,   44,   40,   44,   44,   44,   44,   44,   44,
-       44,   44,   44,   44,   31,   44,   44,   44,   44,   44,
-       44,   11,   44,   44,   44,   44,   44,   44,   44,   44,
-       44,   43,   43,   44,    0,   38,   44,   44,   21,   44,
-       44,   30,   35,   44,   44,   44,   44,   44,   18,   44,
-       44,   29,   44,   27,   44,   44,   12,   44,   15,   17,
-
-       44,   44,   44,   25,   44,   26,   44,    0,   41,    4,
-       44,   44,   44,   28,   44,   44,   44,   44,   44,   44,
-       44,   44,   24,   44,   44,   44,   44,   44,   42,   42,
-       44,   44,   44,    8,   44,   44,   44,   44,   44,   19,
-       44,   44,   10,   44,   44,   44,   44,    5,   22,   44,
-       44,   13,   44,   16,   44,    9,   44,   44,   44,   44,
-       44,   23,   33,   44,   44,   44,   44,   44,   44,   44,
-       44,   44,    6,   44,   44,   44,    7,   44,   14,   44,
-       44,   44,   32,   44,   44,   20,   44,   34,   44,   44,
-       44,   44,   36,    0
-
+        0,    0,   49,   47,    1,    3,   47,   47,   47,   42,
+       42,   40,   43,   47,   43,   43,   43,   43,   43,   47,
+       47,   47,   47,   47,   47,   47,   47,   47,   47,   47,
+        1,    3,   47,    0,   47,   47,    0,    2,   42,   43,
+       47,   47,   47,    8,   47,   47,   43,   47,   47,   47,
+       47,   47,   47,   47,   47,   47,   47,   34,   47,   47,
+       47,   47,   47,   47,   14,   47,   47,   47,   47,   47,
+       47,   47,   47,   47,   46,   46,   47,    0,   41,   47,
+       47,   47,   24,   47,   47,   33,   38,   47,   47,   47,
+       47,   47,   21,   47,   47,   32,   47,   30,   47,   47,
+
+       15,   47,   18,   20,   47,   47,   47,   28,   47,   29,
+        7,   47,    0,   44,   47,    4,   47,   47,   47,   31,
+       47,   47,   47,   47,   47,   47,   47,   47,   27,   47,
+       47,   47,   47,   47,   45,   45,    6,   47,   47,   47,
+       11,   47,   47,   47,   47,   47,   22,   47,   47,   13,
+       47,   47,   47,   47,    5,   25,   47,   47,   16,   47,
+       19,   47,   12,   47,   47,   47,   47,   47,   26,   36,
+       47,   47,   47,   47,   47,   47,   47,   47,   47,    9,
+       47,   47,   47,   10,   47,   17,   47,   47,   47,   35,
+       47,   47,   23,   47,   37,   47,   47,   47,   47,   39,
+
+        0
     } ;
 
 static const YY_CHAR yy_ec[256] =
@@ -424,134 +425,136 @@ static const YY_CHAR yy_meta[40] =
         1,    1,    1,    1,    1,    1,    1,    1,    1
     } ;
 
-static const flex_int16_t yy_base[202] =
+static const flex_int16_t yy_base[209] =
     {   0,
-        0,    0,  265,    0,  262,  266,  260,   38,   42,   39,
-      224,    0,   45,  247,   55,   79,   61,   58,  239,  234,
-       46,   54,   55,   68,   73,  237,   46,  224,    0,  254,
-      266,  101,  250,  107,  111,  251,  266,    0,  108,  111,
-      238,  227,  216,  117,  223,  218,  228,  217,  225,  229,
-      216,  223,  223,  217,  223,  208,  208,  218,  208,  210,
-      212,    0,  199,  207,  201,  201,  206,  210,  202,  208,
-      207,    0,  266,  132,  219,    0,  212,  192,  205,  195,
-      202,    0,    0,  193,  191,  197,  194,  194,    0,  192,
-      182,    0,  186,    0,  190,  180,    0,  183,    0,    0,
-
-      189,  181,  180,    0,  171,    0,  198,  197,    0,    0,
-      182,  181,  174,    0,  178,  168,  164,  174,  162,  168,
-      173,  174,    0,  161,  168,  155,  158,  147,    0,  266,
-      159,  163,  155,    0,  154,  156,  152,  154,  159,    0,
-      143,  148,    0,  141,  141,  140,  137,    0,    0,  149,
-      151,    0,  135,  152,  138,    0,  145,  136,  117,  117,
-      124,    0,    0,  123,  115,  114,  112,  123,  109,  119,
-      109,  101,    0,  113,  111,  115,    0,   96,    0,   92,
-       82,   70,    0,   65,   77,    0,   77,    0,   71,   59,
-       44,   30,    0,  266,   41,  153,  155,  157,  159,  161,
-
-      163
+        0,    0,  274,    0,  271,  275,  269,   38,   42,   39,
+      233,    0,   45,  256,   55,   59,   83,   65,   62,  248,
+      243,   68,   25,   48,   54,   75,  246,   75,  233,    0,
+      263,  275,  106,  259,  111,   76,  260,  275,    0,  110,
+      113,  247,  236,    0,  235,  224,  119,  231,  226,  236,
+      225,  233,  237,  224,  231,  231,  225,  231,  216,  216,
+      226,  216,  218,  220,    0,  207,  215,  209,  209,  214,
+      218,  210,  216,  118,    0,  275,  135,  228,    0,  221,
+      214,  200,  213,  203,  210,    0,    0,  201,  199,  205,
+      202,  202,    0,  200,  190,    0,  194,    0,  198,  188,
+
+        0,  191,    0,    0,  197,  189,  188,    0,  179,    0,
+        0,  206,  205,    0,  176,    0,  189,  188,  181,    0,
+      185,  175,  171,  181,  169,  175,  180,  181,    0,  168,
+      175,  162,  165,  154,    0,  275,    0,  166,  170,  162,
+        0,  161,  163,  159,  161,  166,    0,  150,  155,    0,
+      148,  148,  147,  144,    0,    0,  156,  158,    0,  142,
+      159,  145,    0,  152,  156,  137,  137,  144,    0,    0,
+      143,  122,  121,  119,  130,  116,  126,  116,  108,    0,
+      120,  118,  123,    0,  112,    0,  113,  116,   97,    0,
+       89,   86,    0,   85,    0,   75,   65,   52,   61,    0,
+
+      275,   48,  155,  157,  159,  161,  163,  165
     } ;
 
-static const flex_int16_t yy_def[202] =
+static const flex_int16_t yy_def[209] =
     {   0,
-      194,    1,  194,  195,  194,  194,  195,  196,  197,  195,
-       10,  195,   10,  195,   10,   10,   10,   10,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  194,
-      194,  196,  198,  199,  197,  200,  194,   10,   10,   10,
-      195,  195,  195,   10,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  194,  199,  201,   40,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-
-      195,  195,  195,  195,  195,  195,  195,  194,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  194,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,  195,  195,  195,  195,  195,  195,  195,
-      195,  195,  195,    0,  194,  194,  194,  194,  194,  194,
-
-      194
+      201,    1,  201,  202,  201,  201,  202,  203,  204,  202,
+       10,  202,   10,  202,   10,   10,   10,   10,   10,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      201,  201,  203,  205,  206,  204,  207,  201,   10,   10,
+       10,  202,  202,  202,  202,  202,   10,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  201,  206,  208,   41,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  201,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  201,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+      202,  202,  202,  202,  202,  202,  202,  202,  202,  202,
+
+        0,  201,  201,  201,  201,  201,  201,  201
     } ;
 
-static const flex_int16_t yy_nxt[306] =
+static const flex_int16_t yy_nxt[315] =
     {   0,
         4,    5,    6,    7,    8,    9,   10,   11,   10,   12,
-       13,   13,   14,    4,    4,    4,   13,   13,   15,   16,
-       17,   18,   19,   20,   21,   22,   23,    4,   24,   25,
-        4,   26,   27,    4,   28,    4,    4,    4,    4,   33,
-       33,   29,   34,   36,   37,   38,   38,   38,  193,   39,
-       39,   39,   39,   39,   53,   39,   39,   39,   39,   39,
-       39,   39,   39,   39,   39,   39,   39,   39,   39,   39,
-       57,   59,   68,   54,   55,   69,  192,   56,   42,  191,
-       70,   60,   49,   58,   43,   39,   39,   39,   47,   61,
-      190,   64,  189,   48,   50,   62,  188,   63,  187,   44,
-
-       65,  186,   33,   33,   66,   72,  185,   45,   75,   75,
-       46,   29,   36,   37,   39,   39,   39,   76,   76,   76,
-      184,   76,   76,   39,   39,   39,  183,   76,   76,   76,
-       76,   76,   76,   75,   75,  182,  107,  181,  180,  179,
-      178,  177,  176,  175,  174,  173,  172,  171,  170,  169,
-      168,  167,   80,   32,   32,   35,   35,   33,   33,   74,
-       74,   36,   36,   75,   75,  166,  165,  164,  163,  162,
-      161,  160,  159,  158,  157,  156,  155,  154,  153,  152,
-      151,  150,  149,  148,  147,  146,  145,  144,  143,  142,
-      141,  140,  139,  138,  137,  136,  135,  134,  133,  132,
-
-      131,  130,  129,  128,  127,  126,  125,  124,  123,  122,
-      121,  120,  119,  118,  117,  116,  115,  114,  113,  112,
-      111,  110,  109,  108,  106,  105,  104,  103,  102,  101,
-      100,   99,   98,   97,   96,   95,   94,   93,   92,   91,
-       90,   89,   88,   87,   86,   85,   84,   83,   82,   81,
-       79,   78,   77,   37,   73,   30,   71,   67,   52,   51,
-       41,   40,   31,   30,  194,    3,  194,  194,  194,  194,
-      194,  194,  194,  194,  194,  194,  194,  194,  194,  194,
-      194,  194,  194,  194,  194,  194,  194,  194,  194,  194,
-      194,  194,  194,  194,  194,  194,  194,  194,  194,  194,
-
-      194,  194,  194,  194,  194
+       13,   13,   14,    4,    4,    4,   15,   13,   16,   17,
+       18,   19,   20,   21,   22,   23,   24,    4,   25,   26,
+        4,   27,   28,    4,   29,    4,    4,    4,    4,   34,
+       34,   60,   35,   37,   38,   39,   39,   39,   30,   40,
+       40,   40,   40,   40,   61,   40,   40,   40,   40,   40,
+       40,   40,   40,   40,   62,   40,   40,   40,   40,   40,
+       40,   40,   40,   40,   63,   64,   56,   37,   38,  200,
+       43,   65,   45,   66,  199,  198,   52,   44,   46,   40,
+       40,   40,   50,   67,  197,   57,   58,   51,   53,   59,
+
+      196,   71,   68,   47,   72,  195,   69,   34,   34,   73,
+       75,   48,   78,   78,   49,   30,   40,   40,   40,   79,
+       79,   79,  194,   79,   79,   40,   40,   40,  193,   79,
+       79,   79,   79,   79,   79,  110,   78,   78,  111,  112,
+      192,  191,  190,  189,  188,  187,  186,  185,  184,  183,
+      182,  181,  180,  179,   84,   33,   33,   36,   36,   34,
+       34,   77,   77,   37,   37,   78,   78,  178,  177,  176,
+      175,  174,  173,  172,  171,  170,  169,  168,  167,  166,
+      165,  164,  163,  162,  161,  160,  159,  158,  157,  156,
+      155,  154,  153,  152,  151,  150,  149,  148,  147,  146,
+
+      145,  144,  143,  142,  141,  140,  139,  138,  137,  136,
+      135,  134,  133,  132,  131,  130,  129,  128,  127,  126,
+      125,  124,  123,  122,  121,  120,  119,  118,  117,  116,
+      115,  114,  113,  109,  108,  107,  106,  105,  104,  103,
+      102,  101,  100,   99,   98,   97,   96,   95,   94,   93,
+       92,   91,   90,   89,   88,   87,   86,   85,   83,   82,
+       81,   80,   38,   76,   31,   74,   70,   55,   54,   42,
+       41,   32,   31,  201,    3,  201,  201,  201,  201,  201,
+      201,  201,  201,  201,  201,  201,  201,  201,  201,  201,
+      201,  201,  201,  201,  201,  201,  201,  201,  201,  201,
+
+      201,  201,  201,  201,  201,  201,  201,  201,  201,  201,
+      201,  201,  201,  201
     } ;
 
-static const flex_int16_t yy_chk[306] =
+static const flex_int16_t yy_chk[315] =
     {   0,
         1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
         1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
         1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
         1,    1,    1,    1,    1,    1,    1,    1,    1,    8,
-        8,  195,    8,    9,    9,   10,   10,   10,  192,   10,
-       10,   13,   13,   13,   21,   10,   10,   10,   10,   10,
-       10,   15,   15,   15,   18,   18,   18,   17,   17,   17,
-       22,   23,   27,   21,   21,   27,  191,   21,   15,  190,
-       27,   23,   18,   22,   15,   16,   16,   16,   17,   24,
-      189,   25,  187,   17,   18,   24,  185,   24,  184,   16,
-
-       25,  182,   32,   32,   25,   32,  181,   16,   34,   34,
-       16,   34,   35,   35,   39,   39,   39,   40,   40,   40,
-      180,   40,   40,   44,   44,   44,  178,   40,   40,   40,
-       40,   40,   40,   74,   74,  176,   74,  175,  174,  172,
-      171,  170,  169,  168,  167,  166,  165,  164,  161,  160,
-      159,  158,   44,  196,  196,  197,  197,  198,  198,  199,
-      199,  200,  200,  201,  201,  157,  155,  154,  153,  151,
-      150,  147,  146,  145,  144,  142,  141,  139,  138,  137,
-      136,  135,  133,  132,  131,  128,  127,  126,  125,  124,
-      122,  121,  120,  119,  118,  117,  116,  115,  113,  112,
-
-      111,  108,  107,  105,  103,  102,  101,   98,   96,   95,
-       93,   91,   90,   88,   87,   86,   85,   84,   81,   80,
-       79,   78,   77,   75,   71,   70,   69,   68,   67,   66,
-       65,   64,   63,   61,   60,   59,   58,   57,   56,   55,
-       54,   53,   52,   51,   50,   49,   48,   47,   46,   45,
-       43,   42,   41,   36,   33,   30,   28,   26,   20,   19,
-       14,   11,    7,    5,    3,  194,  194,  194,  194,  194,
-      194,  194,  194,  194,  194,  194,  194,  194,  194,  194,
-      194,  194,  194,  194,  194,  194,  194,  194,  194,  194,
-      194,  194,  194,  194,  194,  194,  194,  194,  194,  194,
-
-      194,  194,  194,  194,  194
+        8,   23,    8,    9,    9,   10,   10,   10,  202,   10,
+       10,   13,   13,   13,   23,   10,   10,   10,   10,   10,
+       10,   15,   15,   15,   24,   16,   16,   16,   19,   19,
+       19,   18,   18,   18,   24,   25,   22,   36,   36,  199,
+       15,   25,   16,   25,  198,  197,   19,   15,   16,   17,
+       17,   17,   18,   26,  196,   22,   22,   18,   19,   22,
+
+      194,   28,   26,   17,   28,  192,   26,   33,   33,   28,
+       33,   17,   35,   35,   17,   35,   40,   40,   40,   41,
+       41,   41,  191,   41,   41,   47,   47,   47,  189,   41,
+       41,   41,   41,   41,   41,   74,   77,   77,   74,   77,
+      188,  187,  185,  183,  182,  181,  179,  178,  177,  176,
+      175,  174,  173,  172,   47,  203,  203,  204,  204,  205,
+      205,  206,  206,  207,  207,  208,  208,  171,  168,  167,
+      166,  165,  164,  162,  161,  160,  158,  157,  154,  153,
+      152,  151,  149,  148,  146,  145,  144,  143,  142,  140,
+      139,  138,  134,  133,  132,  131,  130,  128,  127,  126,
+
+      125,  124,  123,  122,  121,  119,  118,  117,  115,  113,
+      112,  109,  107,  106,  105,  102,  100,   99,   97,   95,
+       94,   92,   91,   90,   89,   88,   85,   84,   83,   82,
+       81,   80,   78,   73,   72,   71,   70,   69,   68,   67,
+       66,   64,   63,   62,   61,   60,   59,   58,   57,   56,
+       55,   54,   53,   52,   51,   50,   49,   48,   46,   45,
+       43,   42,   37,   34,   31,   29,   27,   21,   20,   14,
+       11,    7,    5,    3,  201,  201,  201,  201,  201,  201,
+      201,  201,  201,  201,  201,  201,  201,  201,  201,  201,
+      201,  201,  201,  201,  201,  201,  201,  201,  201,  201,
+
+      201,  201,  201,  201,  201,  201,  201,  201,  201,  201,
+      201,  201,  201,  201
     } ;
 
 static yy_state_type yy_last_accepting_state;
@@ -816,13 +819,13 @@ yy_match:
 			while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
 				{
 				yy_current_state = (int) yy_def[yy_current_state];
-				if ( yy_current_state >= 195 )
+				if ( yy_current_state >= 202 )
 					yy_c = yy_meta[yy_c];
 				}
 			yy_current_state = yy_nxt[yy_base[yy_current_state] + yy_c];
 			++yy_cp;
 			}
-		while ( yy_base[yy_current_state] != 266 );
+		while ( yy_base[yy_current_state] != 275 );
 
 yy_find_action:
 		yy_act = yy_accept[yy_current_state];
@@ -870,163 +873,175 @@ YY_RULE_SETUP
 	YY_BREAK
 case 6:
 YY_RULE_SETUP
-{return(REGISTER);}
+{return(ALIAS);}
 	YY_BREAK
 case 7:
 YY_RULE_SETUP
-{return(FW_CONFIG_TABLE);}
+{return(REFERENCE);}
 	YY_BREAK
 case 8:
 YY_RULE_SETUP
-{return(FW_CONFIG_FIELD);}
+{return(ASSOCIATION);}
 	YY_BREAK
 case 9:
 YY_RULE_SETUP
-{return(FW_CONFIG_OPTION);}
+{return(REGISTER);}
 	YY_BREAK
 case 10:
 YY_RULE_SETUP
-{return(FW_CONFIG_PROBE);}
+{return(FW_CONFIG_TABLE);}
 	YY_BREAK
 case 11:
 YY_RULE_SETUP
-{yylval.number=1; return(BOOL);}
+{return(FW_CONFIG_FIELD);}
 	YY_BREAK
 case 12:
 YY_RULE_SETUP
-{yylval.number=0; return(BOOL);}
+{return(FW_CONFIG_OPTION);}
 	YY_BREAK
 case 13:
 YY_RULE_SETUP
-{yylval.number=3; return(STATUS);}
+{return(FW_CONFIG_PROBE);}
 	YY_BREAK
 case 14:
 YY_RULE_SETUP
-{yylval.number=5; return(STATUS);}
+{yylval.number=1; return(BOOL);}
 	YY_BREAK
 case 15:
 YY_RULE_SETUP
-{yylval.number=PCI; return(BUS);}
+{yylval.number=0; return(BOOL);}
 	YY_BREAK
 case 16:
 YY_RULE_SETUP
-{yylval.number=IOAPIC; return(BUS);}
+{yylval.number=3; return(STATUS);}
 	YY_BREAK
 case 17:
 YY_RULE_SETUP
-{yylval.number=PNP; return(BUS);}
+{yylval.number=5; return(STATUS);}
 	YY_BREAK
 case 18:
 YY_RULE_SETUP
-{yylval.number=I2C; return(BUS);}
+{yylval.number=PCI; return(BUS);}
 	YY_BREAK
 case 19:
 YY_RULE_SETUP
-{yylval.number=APIC; return(BUS);}
+{yylval.number=IOAPIC; return(BUS);}
 	YY_BREAK
 case 20:
 YY_RULE_SETUP
-{yylval.number=CPU_CLUSTER; return(BUS);}
+{yylval.number=PNP; return(BUS);}
 	YY_BREAK
 case 21:
 YY_RULE_SETUP
-{yylval.number=CPU; return(BUS);}
+{yylval.number=I2C; return(BUS);}
 	YY_BREAK
 case 22:
 YY_RULE_SETUP
-{yylval.number=DOMAIN; return(BUS);}
+{yylval.number=APIC; return(BUS);}
 	YY_BREAK
 case 23:
 YY_RULE_SETUP
-{yylval.number=GENERIC; return(BUS);}
+{yylval.number=CPU_CLUSTER; return(BUS);}
 	YY_BREAK
 case 24:
 YY_RULE_SETUP
-{yylval.number=MMIO; return(BUS);}
+{yylval.number=CPU; return(BUS);}
 	YY_BREAK
 case 25:
 YY_RULE_SETUP
-{yylval.number=SPI; return(BUS);}
+{yylval.number=DOMAIN; return(BUS);}
 	YY_BREAK
 case 26:
 YY_RULE_SETUP
-{yylval.number=USB; return(BUS);}
+{yylval.number=GENERIC; return(BUS);}
 	YY_BREAK
 case 27:
 YY_RULE_SETUP
-{yylval.number=LPC; return(BUS);}
+{yylval.number=MMIO; return(BUS);}
 	YY_BREAK
 case 28:
 YY_RULE_SETUP
-{yylval.number=ESPI; return(BUS);}
+{yylval.number=SPI; return(BUS);}
 	YY_BREAK
 case 29:
 YY_RULE_SETUP
-{yylval.number=IRQ; return(RESOURCE);}
+{yylval.number=USB; return(BUS);}
 	YY_BREAK
 case 30:
 YY_RULE_SETUP
-{yylval.number=DRQ; return(RESOURCE);}
+{yylval.number=LPC; return(BUS);}
 	YY_BREAK
 case 31:
 YY_RULE_SETUP
-{yylval.number=IO; return(RESOURCE);}
+{yylval.number=ESPI; return(BUS);}
 	YY_BREAK
 case 32:
 YY_RULE_SETUP
-{return(IOAPIC_IRQ);}
+{yylval.number=IRQ; return(RESOURCE);}
 	YY_BREAK
 case 33:
 YY_RULE_SETUP
-{return(INHERIT);}
+{yylval.number=DRQ; return(RESOURCE);}
 	YY_BREAK
 case 34:
 YY_RULE_SETUP
-{return(SUBSYSTEMID);}
+{yylval.number=IO; return(RESOURCE);}
 	YY_BREAK
 case 35:
 YY_RULE_SETUP
-{return(END);}
+{return(IOAPIC_IRQ);}
 	YY_BREAK
 case 36:
 YY_RULE_SETUP
-{return(SLOT_DESC);}
+{return(INHERIT);}
 	YY_BREAK
 case 37:
 YY_RULE_SETUP
-{return(EQUALS);}
+{return(SUBSYSTEMID);}
 	YY_BREAK
 case 38:
 YY_RULE_SETUP
-{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(NUMBER);}
+{return(END);}
 	YY_BREAK
 case 39:
 YY_RULE_SETUP
-{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(NUMBER);}
+{return(SLOT_DESC);}
 	YY_BREAK
 case 40:
 YY_RULE_SETUP
-{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(NUMBER);}
+{return(EQUALS);}
 	YY_BREAK
 case 41:
 YY_RULE_SETUP
-{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(PCIINT);}
+{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(NUMBER);}
 	YY_BREAK
 case 42:
-/* rule 42 can match eol */
 YY_RULE_SETUP
-{yylval.string = malloc(yyleng-1); strncpy(yylval.string, yytext+1, yyleng-2); yylval.string[yyleng-2]='\0'; return(STRING);}
+{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(NUMBER);}
 	YY_BREAK
 case 43:
-/* rule 43 can match eol */
 YY_RULE_SETUP
-{yylval.string = malloc(yyleng-1); strncpy(yylval.string, yytext+1, yyleng-2); yylval.string[yyleng-2]='\0'; return(STRING);}
+{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(NUMBER);}
 	YY_BREAK
 case 44:
 YY_RULE_SETUP
-{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(STRING);}
+{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(PCIINT);}
 	YY_BREAK
 case 45:
+/* rule 45 can match eol */
+YY_RULE_SETUP
+{yylval.string = malloc(yyleng-1); strncpy(yylval.string, yytext+1, yyleng-2); yylval.string[yyleng-2]='\0'; return(STRING);}
+	YY_BREAK
+case 46:
+/* rule 46 can match eol */
+YY_RULE_SETUP
+{yylval.string = malloc(yyleng-1); strncpy(yylval.string, yytext+1, yyleng-2); yylval.string[yyleng-2]='\0'; return(STRING);}
+	YY_BREAK
+case 47:
+YY_RULE_SETUP
+{yylval.string = malloc(yyleng+1); strncpy(yylval.string, yytext, yyleng); yylval.string[yyleng]='\0'; return(STRING);}
+	YY_BREAK
+case 48:
 YY_RULE_SETUP
 ECHO;
 	YY_BREAK
@@ -1326,7 +1341,7 @@ static int yy_get_next_buffer (void)
 		while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
 			{
 			yy_current_state = (int) yy_def[yy_current_state];
-			if ( yy_current_state >= 195 )
+			if ( yy_current_state >= 202 )
 				yy_c = yy_meta[yy_c];
 			}
 		yy_current_state = yy_nxt[yy_base[yy_current_state] + yy_c];
@@ -1354,11 +1369,11 @@ static int yy_get_next_buffer (void)
 	while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
 		{
 		yy_current_state = (int) yy_def[yy_current_state];
-		if ( yy_current_state >= 195 )
+		if ( yy_current_state >= 202 )
 			yy_c = yy_meta[yy_c];
 		}
 	yy_current_state = yy_nxt[yy_base[yy_current_state] + yy_c];
-	yy_is_jam = (yy_current_state == 194);
+	yy_is_jam = (yy_current_state == 201);
 
 		return yy_is_jam ? 0 : yy_current_state;
 }
diff --git a/util/sconfig/main.c b/util/sconfig/main.c
index b0c32f677a..170acadec7 100644
--- a/util/sconfig/main.c
+++ b/util/sconfig/main.c
@@ -669,16 +669,41 @@ static void set_new_child(struct bus *parent, struct device *child)
 	child->parent = parent;
 }
 
+static const struct device *find_alias(const struct device *const parent,
+				       const char *const alias)
+{
+	if (parent->alias && !strcmp(parent->alias, alias))
+		return parent;
+
+	const struct bus *bus;
+	for (bus = parent->bus; bus; bus = bus->next_bus) {
+		const struct device *child;
+		for (child = bus->children; child; child = child->sibling) {
+			const struct device *const ret = find_alias(child, alias);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return NULL;
+}
+
 struct device *new_device(struct bus *parent,
 			  struct chip_instance *chip_instance,
 			  const int bustype, const char *devnum,
-			  int status)
+			  char *alias, int status)
 {
 	char *tmp;
 	int path_a;
 	int path_b = 0;
 	struct device *new_d;
 
+	/* Check for alias name conflicts. */
+	if (alias && find_alias(&base_root_dev, alias)) {
+		printf("ERROR: Alias already exists: %s\n", alias);
+		exit(1);
+	}
+
 	path_a = strtol(devnum, &tmp, 16);
 	if (*tmp == '.') {
 		tmp++;
@@ -698,6 +723,7 @@ struct device *new_device(struct bus *parent,
 
 	new_d->path_a = path_a;
 	new_d->path_b = path_b;
+	new_d->alias = alias;
 
 	new_d->enabled = status & 0x01;
 	new_d->hidden = (status >> 1) & 0x01;
@@ -819,6 +845,35 @@ void add_register(struct chip_instance *chip_instance, char *name, char *val)
 	add_reg(&chip_instance->reg, name, val);
 }
 
+void add_reference(struct chip_instance *const chip_instance,
+		   char *const name, char *const alias)
+{
+	add_reg(&chip_instance->ref, name, alias);
+}
+
+static void set_reference(struct chip_instance *const chip_instance,
+			  char *const name, char *const alias)
+{
+	const struct device *const dev = find_alias(&base_root_dev, alias);
+	if (!dev) {
+		printf("ERROR: Cannot find device alias '%s'.\n", alias);
+		exit(1);
+	}
+
+	char *const ref_name = S_ALLOC(strlen(dev->name) + 2);
+	sprintf(ref_name, "&%s", dev->name);
+	add_register(chip_instance, name, ref_name);
+}
+
+static void update_references(FILE *file, FILE *head, struct device *dev,
+			      struct device *next)
+{
+	struct reg *ref;
+
+	for (ref = dev->chip_instance->ref; ref; ref = ref->next)
+		set_reference(dev->chip_instance, ref->key, ref->value);
+}
+
 void add_slot_desc(struct bus *bus, char *type, char *length, char *designation,
 		   char *data_width)
 {
@@ -1203,16 +1258,12 @@ static void emit_chip_instance(FILE *fil, struct chip_instance *instance)
 	fprintf(fil, "};\n\n");
 }
 
-static void emit_chips(FILE *fil)
+static void emit_chip_configs(FILE *fil)
 {
 	struct chip *chip = chip_header.next;
 	struct chip_instance *instance;
 	int chip_id;
 
-	emit_chip_headers(fil, chip);
-
-	fprintf(fil, "\n#define STORAGE static __unused DEVTREE_CONST\n\n");
-
 	for (; chip; chip = chip->next) {
 		if (!chip->chiph_exists)
 			continue;
@@ -1337,9 +1388,9 @@ static void update_resource(struct device *dev, struct resource *res)
  * Add register to chip instance. If register is already present, then update
  * its value. If not, then add a new register to the chip instance.
  */
-static void update_register(struct chip_instance *c, struct reg *reg)
+static void update_register(struct reg **const head, struct reg *reg)
 {
-	struct reg *base_reg = c->reg;
+	struct reg *base_reg = *head;
 
 	while (base_reg) {
 		if (!strcmp(base_reg->key, reg->key)) {
@@ -1349,7 +1400,7 @@ static void update_register(struct chip_instance *c, struct reg *reg)
 		base_reg = base_reg->next;
 	}
 
-	add_register(c, reg->key, reg->value);
+	add_reg(head, reg->key, reg->value);
 }
 
 static void override_devicetree(struct bus *base_parent,
@@ -1422,6 +1473,19 @@ static void override_devicetree(struct bus *base_parent,
  * |                    |                                            |
  * +-----------------------------------------------------------------+
  * |                    |                                            |
+ * | ref                | Each reference that is present in override |
+ * |                    | device is copied over to base device with  |
+ * |                    | the same rules as registers.               |
+ * |                    |                                            |
+ * +-----------------------------------------------------------------+
+ * |                    |                                            |
+ * | alias              | Base device alias is copied to override.   |
+ * |                    | Override devices cannot change/remove an   |
+ * |                    | existing alias, but they can add an alias  |
+ * |                    | if one does not exist.                     |
+ * |                    |                                            |
+ * +-----------------------------------------------------------------+
+ * |                    |                                            |
  * | chip_instance      | Each register of chip_instance is copied   |
  * |                    | over from override device to base device:  |
  * |                    | 1. If register with same key is present in |
@@ -1492,10 +1556,34 @@ static void update_device(struct device *base_dev, struct device *override_dev)
 	 */
 	struct reg *reg = override_dev->chip_instance->reg;
 	while (reg) {
-		update_register(base_dev->chip_instance, reg);
+		update_register(&base_dev->chip_instance->reg, reg);
 		reg = reg->next;
 	}
 
+	/* Copy references just as with registers. */
+	reg = override_dev->chip_instance->ref;
+	while (reg) {
+		update_register(&base_dev->chip_instance->ref, reg);
+		reg = reg->next;
+	}
+
+	/* Check for alias name conflicts. */
+	if (override_dev->alias && find_alias(&base_root_dev, override_dev->alias)) {
+		printf("ERROR: alias already exists: %s\n", override_dev->alias);
+		exit(1);
+	}
+
+	/*
+	 * Copy alias from base device.
+	 *
+	 * Override devices cannot change/remove an existing alias,
+	 * but they can add an alias to a device if one does not exist yet.
+	 */
+	if (base_dev->alias)
+		override_dev->alias = base_dev->alias;
+	else
+		base_dev->alias = override_dev->alias;
+
 	/*
 	 * Use probe list from override device in place of base device, in order
 	 * to allow an override to remove a probe from the base device.
@@ -1631,12 +1719,15 @@ int main(int argc, char **argv)
 	fprintf(autogen, "#include <device/device.h>\n");
 	fprintf(autogen, "#include <device/pci.h>\n\n");
 	fprintf(autogen, "#include <static.h>\n");
-
-	emit_chips(autogen);
+	emit_chip_headers(autogen, chip_header.next);
+	fprintf(autogen, "\n#define STORAGE static __unused DEVTREE_CONST\n\n");
 
 	walk_device_tree(autogen, autohead, &base_root_dev, inherit_subsystem_ids);
 	fprintf(autogen, "\n/* pass 0 */\n");
 	walk_device_tree(autogen, autohead, &base_root_dev, pass0);
+	walk_device_tree(autogen, autohead, &base_root_dev, update_references);
+	fprintf(autogen, "\n/* chip configs */\n");
+	emit_chip_configs(autogen);
 	fprintf(autogen, "\n/* pass 1 */\n");
 	walk_device_tree(autogen, autohead, &base_root_dev, pass1);
 
diff --git a/util/sconfig/sconfig.h b/util/sconfig/sconfig.h
index 1bbff4644c..719519e855 100644
--- a/util/sconfig/sconfig.h
+++ b/util/sconfig/sconfig.h
@@ -57,6 +57,9 @@ struct chip_instance {
 	/* Pointer to registers for this chip. */
 	struct reg *reg;
 
+	/* Pointer to references for this chip. */
+	struct reg *ref;
+
 	/* Pointer to chip of which this is instance. */
 	struct chip *chip;
 
@@ -123,6 +126,9 @@ struct device {
 	/* Name of this device. */
 	char *name;
 
+	/* Alias of this device (for internal references) */
+	char *alias;
+
 	/* Path of this device. */
 	char *path;
 	int path_a;
@@ -172,7 +178,7 @@ extern struct bus *root_parent;
 struct device *new_device(struct bus *parent,
 			  struct chip_instance *chip_instance,
 			  const int bustype, const char *devnum,
-			  int status);
+			  char *alias, int status);
 
 void add_resource(struct bus *bus, int type, int index, int base);
 
@@ -195,6 +201,7 @@ void *chip_dequeue_tail(void);
 
 struct chip_instance *new_chip_instance(char *path);
 void add_register(struct chip_instance *chip, char *name, char *val);
+void add_reference(struct chip_instance *chip, char *name, char *alias);
 
 struct fw_config_field *get_fw_config_field(const char *name);
 
diff --git a/util/sconfig/sconfig.l b/util/sconfig/sconfig.l
index 10a86a2f2b..0505150263 100755
--- a/util/sconfig/sconfig.l
+++ b/util/sconfig/sconfig.l
@@ -13,6 +13,9 @@ int linenum = 0;
 \r?\n			{linenum++;}
 chip			{return(CHIP);}
 device			{return(DEVICE);}
+alias			{return(ALIAS);}
+use			{return(REFERENCE);}
+as			{return(ASSOCIATION);}
 register		{return(REGISTER);}
 fw_config		{return(FW_CONFIG_TABLE);}
 field			{return(FW_CONFIG_FIELD);}
diff --git a/util/sconfig/sconfig.tab.c_shipped b/util/sconfig/sconfig.tab.c_shipped
index c78f1ace25..52bb79cbfc 100644
--- a/util/sconfig/sconfig.tab.c_shipped
+++ b/util/sconfig/sconfig.tab.c_shipped
@@ -1,4 +1,4 @@
-/* A Bison parser, made by GNU Bison 3.5.1.  */
+/* A Bison parser, made by GNU Bison 3.5.3.  */
 
 /* Bison implementation for Yacc-like parsers in C
 
@@ -48,7 +48,7 @@
 #define YYBISON 1
 
 /* Bison version.  */
-#define YYBISON_VERSION "3.5.1"
+#define YYBISON_VERSION "3.5.3"
 
 /* Skeleton name.  */
 #define YYSKELETON_NAME "yacc.c"
@@ -130,42 +130,45 @@ extern int yydebug;
     CHIP = 258,
     DEVICE = 259,
     REGISTER = 260,
-    BOOL = 261,
-    STATUS = 262,
-    MANDATORY = 263,
-    BUS = 264,
-    RESOURCE = 265,
-    END = 266,
-    EQUALS = 267,
-    HEX = 268,
-    STRING = 269,
-    PCI = 270,
-    PNP = 271,
-    I2C = 272,
-    APIC = 273,
-    CPU_CLUSTER = 274,
-    CPU = 275,
-    DOMAIN = 276,
-    IRQ = 277,
-    DRQ = 278,
-    SLOT_DESC = 279,
-    IO = 280,
-    NUMBER = 281,
-    SUBSYSTEMID = 282,
-    INHERIT = 283,
-    IOAPIC_IRQ = 284,
-    IOAPIC = 285,
-    PCIINT = 286,
-    GENERIC = 287,
-    SPI = 288,
-    USB = 289,
-    MMIO = 290,
-    LPC = 291,
-    ESPI = 292,
-    FW_CONFIG_TABLE = 293,
-    FW_CONFIG_FIELD = 294,
-    FW_CONFIG_OPTION = 295,
-    FW_CONFIG_PROBE = 296
+    ALIAS = 261,
+    REFERENCE = 262,
+    ASSOCIATION = 263,
+    BOOL = 264,
+    STATUS = 265,
+    MANDATORY = 266,
+    BUS = 267,
+    RESOURCE = 268,
+    END = 269,
+    EQUALS = 270,
+    HEX = 271,
+    STRING = 272,
+    PCI = 273,
+    PNP = 274,
+    I2C = 275,
+    APIC = 276,
+    CPU_CLUSTER = 277,
+    CPU = 278,
+    DOMAIN = 279,
+    IRQ = 280,
+    DRQ = 281,
+    SLOT_DESC = 282,
+    IO = 283,
+    NUMBER = 284,
+    SUBSYSTEMID = 285,
+    INHERIT = 286,
+    IOAPIC_IRQ = 287,
+    IOAPIC = 288,
+    PCIINT = 289,
+    GENERIC = 290,
+    SPI = 291,
+    USB = 292,
+    MMIO = 293,
+    LPC = 294,
+    ESPI = 295,
+    FW_CONFIG_TABLE = 296,
+    FW_CONFIG_FIELD = 297,
+    FW_CONFIG_OPTION = 298,
+    FW_CONFIG_PROBE = 299
   };
 #endif
 
@@ -497,19 +500,19 @@ union yyalloc
 /* YYFINAL -- State number of the termination state.  */
 #define YYFINAL  2
 /* YYLAST -- Last index in YYTABLE.  */
-#define YYLAST   58
+#define YYLAST   64
 
 /* YYNTOKENS -- Number of terminals.  */
-#define YYNTOKENS  42
+#define YYNTOKENS  45
 /* YYNNTS -- Number of nonterminals.  */
-#define YYNNTS  23
+#define YYNNTS  25
 /* YYNRULES -- Number of rules.  */
-#define YYNRULES  44
+#define YYNRULES  48
 /* YYNSTATES -- Number of states.  */
-#define YYNSTATES  75
+#define YYNSTATES  83
 
 #define YYUNDEFTOK  2
-#define YYMAXUTOK   296
+#define YYMAXUTOK   299
 
 
 /* YYTRANSLATE(TOKEN-NUM) -- Symbol number corresponding to TOKEN-NUM
@@ -550,18 +553,18 @@ static const yytype_int8 yytranslate[] =
        5,     6,     7,     8,     9,    10,    11,    12,    13,    14,
       15,    16,    17,    18,    19,    20,    21,    22,    23,    24,
       25,    26,    27,    28,    29,    30,    31,    32,    33,    34,
-      35,    36,    37,    38,    39,    40,    41
+      35,    36,    37,    38,    39,    40,    41,    42,    43,    44
 };
 
 #if YYDEBUG
   /* YYRLINE[YYN] -- Source line where rule number YYN was defined.  */
 static const yytype_int8 yyrline[] =
 {
-       0,    24,    24,    24,    24,    26,    26,    26,    26,    28,
-      28,    28,    28,    28,    28,    28,    28,    28,    30,    30,
-      39,    39,    47,    47,    49,    52,    55,    58,    61,    64,
-      67,    70,    74,    77,    77,    80,    80,    83,    83,    89,
-      89,    95,    95,   101,   105
+       0,    24,    24,    24,    24,    26,    26,    26,    26,    26,
+      28,    28,    28,    28,    28,    28,    28,    28,    28,    30,
+      30,    39,    39,    47,    49,    53,    53,    55,    58,    61,
+      64,    67,    70,    73,    76,    79,    83,    86,    86,    89,
+      89,    92,    92,    98,    98,   104,   104,   110,   114
 };
 #endif
 
@@ -570,18 +573,19 @@ static const yytype_int8 yyrline[] =
    First, the terminals, then, starting at YYNTOKENS, nonterminals.  */
 static const char *const yytname[] =
 {
-  "$end", "error", "$undefined", "CHIP", "DEVICE", "REGISTER", "BOOL",
-  "STATUS", "MANDATORY", "BUS", "RESOURCE", "END", "EQUALS", "HEX",
-  "STRING", "PCI", "PNP", "I2C", "APIC", "CPU_CLUSTER", "CPU", "DOMAIN",
-  "IRQ", "DRQ", "SLOT_DESC", "IO", "NUMBER", "SUBSYSTEMID", "INHERIT",
-  "IOAPIC_IRQ", "IOAPIC", "PCIINT", "GENERIC", "SPI", "USB", "MMIO", "LPC",
-  "ESPI", "FW_CONFIG_TABLE", "FW_CONFIG_FIELD", "FW_CONFIG_OPTION",
-  "FW_CONFIG_PROBE", "$accept", "devtree", "chipchildren",
-  "devicechildren", "chip", "@1", "device", "@2", "status", "resource",
-  "registers", "subsystemid", "ioapic_irq", "smbios_slot_desc",
-  "fw_config_table", "fw_config_table_children",
-  "fw_config_field_children", "fw_config_field", "$@3", "$@4", "$@5",
-  "fw_config_option", "fw_config_probe", YY_NULLPTR
+  "$end", "error", "$undefined", "CHIP", "DEVICE", "REGISTER", "ALIAS",
+  "REFERENCE", "ASSOCIATION", "BOOL", "STATUS", "MANDATORY", "BUS",
+  "RESOURCE", "END", "EQUALS", "HEX", "STRING", "PCI", "PNP", "I2C",
+  "APIC", "CPU_CLUSTER", "CPU", "DOMAIN", "IRQ", "DRQ", "SLOT_DESC", "IO",
+  "NUMBER", "SUBSYSTEMID", "INHERIT", "IOAPIC_IRQ", "IOAPIC", "PCIINT",
+  "GENERIC", "SPI", "USB", "MMIO", "LPC", "ESPI", "FW_CONFIG_TABLE",
+  "FW_CONFIG_FIELD", "FW_CONFIG_OPTION", "FW_CONFIG_PROBE", "$accept",
+  "devtree", "chipchildren", "devicechildren", "chip", "@1", "device",
+  "@2", "alias", "status", "resource", "reference", "registers",
+  "subsystemid", "ioapic_irq", "smbios_slot_desc", "fw_config_table",
+  "fw_config_table_children", "fw_config_field_children",
+  "fw_config_field", "$@3", "$@4", "$@5", "fw_config_option",
+  "fw_config_probe", YY_NULLPTR
 };
 #endif
 
@@ -594,11 +598,11 @@ static const yytype_int16 yytoknum[] =
      265,   266,   267,   268,   269,   270,   271,   272,   273,   274,
      275,   276,   277,   278,   279,   280,   281,   282,   283,   284,
      285,   286,   287,   288,   289,   290,   291,   292,   293,   294,
-     295,   296
+     295,   296,   297,   298,   299
 };
 # endif
 
-#define YYPACT_NINF (-12)
+#define YYPACT_NINF (-21)
 
 #define yypact_value_is_default(Yyn) \
   ((Yyn) == YYPACT_NINF)
@@ -612,14 +616,15 @@ static const yytype_int16 yytoknum[] =
      STATE-NUM.  */
 static const yytype_int8 yypact[] =
 {
-     -12,     3,   -12,     4,   -12,   -12,   -12,   -12,    -2,   -12,
-     -12,     8,   -12,     9,     1,    14,    11,   -12,   -12,   -12,
-     -12,     2,   -12,     5,    17,   -12,   -12,    -6,    10,    16,
-     -12,    -1,   -12,    18,   -12,   -12,   -12,   -12,   -12,     0,
-     -12,     7,   -12,   -12,   -12,    -3,    19,   -12,    21,    20,
-      22,    28,   -12,   -12,   -12,   -12,   -12,   -12,   -12,   -12,
-      31,    30,    23,    24,    33,    25,    36,    26,    27,   -12,
-     -12,    38,   -12,   -12,   -12
+     -21,     3,   -21,    -4,   -21,   -21,   -21,   -21,    -2,   -21,
+     -21,     4,   -21,    11,   -20,    14,     6,    13,   -21,   -21,
+     -21,   -21,   -21,    -1,   -21,     2,    17,    26,   -21,   -21,
+     -10,    29,    21,    22,   -21,    -7,   -21,    25,   -21,    30,
+      10,   -21,   -21,    -6,   -21,    19,   -21,   -21,   -21,   -21,
+     -21,   -21,   -21,    -3,    20,   -21,    33,    23,    24,    34,
+     -21,   -21,   -21,   -21,   -21,   -21,   -21,   -21,    28,    37,
+      27,    12,    38,    31,    40,    32,    35,   -21,   -21,    41,
+     -21,   -21,   -21
 };
 
   /* YYDEFACT[STATE-NUM] -- Default reduction number in state STATE-NUM.
@@ -627,30 +632,31 @@ static const yytype_int8 yypact[] =
      means the default is an error.  */
 static const yytype_int8 yydefact[] =
 {
-       2,     0,     1,     0,    34,     3,     4,    18,     0,     8,
-      32,     0,    33,     0,    41,     0,     0,    19,     6,     5,
-       7,    39,    36,     0,     0,    37,    36,     0,     0,     0,
-      36,     0,    42,     0,    35,    22,    23,    20,    25,     0,
-      40,     0,    17,    38,    43,     0,     0,    21,     0,     0,
-       0,     0,    10,     9,    11,    15,    12,    13,    14,    16,
-       0,     0,     0,     0,     0,     0,    31,    26,     0,    44,
-      24,    30,    27,    28,    29
+       2,     0,     1,     0,    38,     3,     4,    19,     0,     9,
+      36,     0,    37,     0,    45,     0,     0,     0,    20,     6,
+       5,     8,     7,    43,    40,     0,     0,     0,    41,    40,
+       0,    23,     0,     0,    40,     0,    46,     0,    39,     0,
+       0,    29,    28,     0,    44,     0,    24,    25,    26,    21,
+      42,    47,    18,     0,     0,    22,     0,     0,     0,     0,
+      11,    10,    12,    16,    13,    14,    15,    17,     0,     0,
+       0,     0,     0,     0,    35,    30,     0,    48,    27,    34,
+      31,    32,    33
 };
 
   /* YYPGOTO[NTERM-NUM].  */
 static const yytype_int8 yypgoto[] =
 {
-     -12,   -12,   -12,   -12,    -9,   -12,    12,   -12,   -12,   -12,
-      13,   -12,   -12,   -12,   -12,   -12,   -11,   -12,   -12,   -12,
-     -12,   -12,   -12
+     -21,   -21,   -21,   -21,    -8,   -21,     8,   -21,   -21,   -21,
+     -21,   -21,     9,   -21,   -21,   -21,   -21,   -21,   -12,   -21,
+     -21,   -21,   -21,   -21,   -21
 };
 
   /* YYDEFGOTO[NTERM-NUM].  */
 static const yytype_int8 yydefgoto[] =
 {
-      -1,     1,    13,    45,     5,     9,    19,    42,    37,    54,
-      20,    56,    57,    58,     6,     8,    27,    12,    30,    26,
-      22,    34,    59
+      -1,     1,    13,    53,     5,     9,    20,    52,    40,    49,
+      62,    21,    22,    64,    65,    66,     6,     8,    30,    12,
+      34,    29,    24,    38,    67
 };
 
   /* YYTABLE[YYPACT[STATE-NUM]] -- What to do in state STATE-NUM.  If
@@ -658,56 +664,59 @@ static const yytype_int8 yydefgoto[] =
      number is the opposite.  If YYTABLE_NINF, syntax error.  */
 static const yytype_int8 yytable[] =
 {
-       3,    15,    16,     2,    18,    32,     3,    46,    47,    10,
-      40,    43,     3,    15,    16,    31,    35,    36,     7,    39,
-      17,    48,    14,    23,    49,    24,    50,    21,    25,    29,
-      38,    28,    41,    44,    33,    61,    52,    11,    51,    33,
-      33,     4,    64,    65,    66,    60,    62,    69,    63,    67,
-      71,    70,    74,    73,    72,    68,     0,    53,    55
+       3,    15,    16,     2,    36,    19,     3,    44,    50,    23,
+      54,    55,    10,     7,     3,    15,    16,    35,    17,    47,
+      48,    14,    43,    26,    56,    18,    25,    57,    28,    58,
+      27,    31,    32,    37,    33,    39,    37,    37,    41,    42,
+      11,    59,    45,    73,     4,    60,    76,    46,    51,    68,
+      69,    72,    70,    71,    74,    77,    75,    79,    82,     0,
+      78,    61,    63,    80,    81
 };
 
 static const yytype_int8 yycheck[] =
 {
-       3,     4,     5,     0,    13,    11,     3,    10,    11,    11,
-      11,    11,     3,     4,     5,    26,     6,     7,    14,    30,
-      11,    24,    14,     9,    27,    14,    29,    26,    26,    12,
-      14,    26,    14,    26,    40,    14,    45,    39,    41,    40,
-      40,    38,    14,    12,    14,    26,    26,    14,    26,    26,
-      14,    26,    14,    26,    28,    31,    -1,    45,    45
+       3,     4,     5,     0,    14,    13,     3,    14,    14,    29,
+      13,    14,    14,    17,     3,     4,     5,    29,     7,     9,
+      10,    17,    34,    17,    27,    14,    12,    30,    29,    32,
+      17,    29,    15,    43,     8,     6,    43,    43,    17,    17,
+      42,    44,    17,    15,    41,    53,    34,    17,    29,    29,
+      17,    17,    29,    29,    17,    17,    29,    17,    17,    -1,
+      29,    53,    53,    31,    29
 };
 
   /* YYSTOS[STATE-NUM] -- The (internal number of the) accessing
      symbol of state STATE-NUM.  */
 static const yytype_int8 yystos[] =
 {
-       0,    43,     0,     3,    38,    46,    56,    14,    57,    47,
-      11,    39,    59,    44,    14,     4,     5,    11,    46,    48,
-      52,    26,    62,     9,    14,    26,    61,    58,    26,    12,
-      60,    58,    11,    40,    63,     6,     7,    50,    14,    58,
-      11,    14,    49,    11,    26,    45,    10,    11,    24,    27,
-      29,    41,    46,    48,    51,    52,    53,    54,    55,    64,
-      26,    14,    26,    26,    14,    12,    14,    26,    31,    14,
-      26,    14,    28,    26,    14
+       0,    46,     0,     3,    41,    49,    61,    17,    62,    50,
+      14,    42,    64,    47,    17,     4,     5,     7,    14,    49,
+      51,    56,    57,    29,    67,    12,    17,    17,    29,    66,
+      63,    29,    15,     8,    65,    63,    14,    43,    68,     6,
+      53,    17,    17,    63,    14,    17,    17,     9,    10,    54,
+      14,    29,    52,    48,    13,    14,    27,    30,    32,    44,
+      49,    51,    55,    57,    58,    59,    60,    69,    29,    17,
+      29,    29,    17,    15,    17,    29,    34,    17,    29,    17,
+      31,    29,    17
 };
 
   /* YYR1[YYN] -- Symbol number of symbol that rule YYN derives.  */
 static const yytype_int8 yyr1[] =
 {
-       0,    42,    43,    43,    43,    44,    44,    44,    44,    45,
-      45,    45,    45,    45,    45,    45,    45,    45,    47,    46,
-      49,    48,    50,    50,    51,    52,    53,    53,    54,    55,
-      55,    55,    56,    57,    57,    58,    58,    60,    59,    61,
-      59,    62,    59,    63,    64
+       0,    45,    46,    46,    46,    47,    47,    47,    47,    47,
+      48,    48,    48,    48,    48,    48,    48,    48,    48,    50,
+      49,    52,    51,    53,    53,    54,    54,    55,    56,    57,
+      58,    58,    59,    60,    60,    60,    61,    62,    62,    63,
+      63,    65,    64,    66,    64,    67,    64,    68,    69
 };
 
   /* YYR2[YYN] -- Number of symbols on the right hand side of rule YYN.  */
 static const yytype_int8 yyr2[] =
 {
-       0,     2,     0,     2,     2,     2,     2,     2,     0,     2,
-       2,     2,     2,     2,     2,     2,     2,     0,     0,     5,
-       0,     7,     1,     1,     4,     4,     3,     4,     4,     5,
-       4,     3,     3,     2,     0,     2,     0,     0,     7,     0,
-       6,     0,     5,     3,     3
+       0,     2,     0,     2,     2,     2,     2,     2,     2,     0,
+       2,     2,     2,     2,     2,     2,     2,     2,     0,     0,
+       5,     0,     8,     0,     2,     1,     1,     4,     4,     4,
+       3,     4,     4,     5,     4,     3,     3,     2,     0,     2,
+       0,     0,     7,     0,     6,     0,     5,     3,     3
 };
 
 
@@ -1406,7 +1415,7 @@ yyreduce:
          { cur_parent = root_parent; }
     break;
 
-  case 18:
+  case 19:
                                 {
 	(yyval.chip_instance) = new_chip_instance((yyvsp[0].string));
 	chip_enqueue_tail(cur_chip_instance);
@@ -1414,96 +1423,112 @@ yyreduce:
 }
     break;
 
-  case 19:
+  case 20:
                          {
 	cur_chip_instance = chip_dequeue_tail();
 }
     break;
 
-  case 20:
-                                                 {
-	(yyval.dev) = new_device(cur_parent, cur_chip_instance, (yyvsp[-2].number), (yyvsp[-1].string), (yyvsp[0].number));
+  case 21:
+                                                       {
+	(yyval.dev) = new_device(cur_parent, cur_chip_instance, (yyvsp[-3].number), (yyvsp[-2].string), (yyvsp[-1].string), (yyvsp[0].number));
 	cur_parent = (yyval.dev)->last_bus;
 }
     break;
 
-  case 21:
+  case 22:
                            {
 	cur_parent = (yyvsp[-2].dev)->parent;
 }
     break;
 
+  case 23:
+                   {
+	(yyval.string) = NULL;
+}
+    break;
+
   case 24:
+                 {
+	(yyval.string) = (yyvsp[0].string);
+}
+    break;
+
+  case 27:
         { add_resource(cur_parent, (yyvsp[-3].number), strtol((yyvsp[-2].string), NULL, 0), strtol((yyvsp[0].string), NULL, 0)); }
     break;
 
-  case 25:
+  case 28:
+        { add_reference(cur_chip_instance, (yyvsp[0].string), (yyvsp[-2].string)); }
+    break;
+
+  case 29:
         { add_register(cur_chip_instance, (yyvsp[-2].string), (yyvsp[0].string)); }
     break;
 
-  case 26:
+  case 30:
         { add_pci_subsystem_ids(cur_parent, strtol((yyvsp[-1].string), NULL, 16), strtol((yyvsp[0].string), NULL, 16), 0); }
     break;
 
-  case 27:
+  case 31:
         { add_pci_subsystem_ids(cur_parent, strtol((yyvsp[-2].string), NULL, 16), strtol((yyvsp[-1].string), NULL, 16), 1); }
     break;
 
-  case 28:
+  case 32:
         { add_ioapic_info(cur_parent, strtol((yyvsp[-2].string), NULL, 16), (yyvsp[-1].string), strtol((yyvsp[0].string), NULL, 16)); }
     break;
 
-  case 29:
+  case 33:
         { add_slot_desc(cur_parent, (yyvsp[-3].string), (yyvsp[-2].string), (yyvsp[-1].string), (yyvsp[0].string)); }
     break;
 
-  case 30:
+  case 34:
         { add_slot_desc(cur_parent, (yyvsp[-2].string), (yyvsp[-1].string), (yyvsp[0].string), NULL); }
     break;
 
-  case 31:
+  case 35:
         { add_slot_desc(cur_parent, (yyvsp[-1].string), (yyvsp[0].string), NULL, NULL); }
     break;
 
-  case 32:
+  case 36:
                                                               { }
     break;
 
-  case 37:
+  case 41:
                                                                                           {
 	cur_field = new_fw_config_field((yyvsp[-2].string), strtoul((yyvsp[-1].string), NULL, 0), strtoul((yyvsp[0].string), NULL, 0));
 }
     break;
 
-  case 38:
+  case 42:
                                      { }
     break;
 
-  case 39:
+  case 43:
                                                             {
 	cur_field = new_fw_config_field((yyvsp[-1].string), strtoul((yyvsp[0].string), NULL, 0), strtoul((yyvsp[0].string), NULL, 0));
 }
     break;
 
-  case 40:
+  case 44:
                                      { }
     break;
 
-  case 41:
+  case 45:
                                         {
 	cur_field = get_fw_config_field((yyvsp[0].string));
 }
     break;
 
-  case 42:
+  case 46:
                                      { }
     break;
 
-  case 43:
+  case 47:
         { add_fw_config_option(cur_field, (yyvsp[-1].string), strtoul((yyvsp[0].string), NULL, 0)); }
     break;
 
-  case 44:
+  case 48:
         { add_fw_config_probe(cur_parent, (yyvsp[-1].string), (yyvsp[0].string)); }
     break;
 
diff --git a/util/sconfig/sconfig.tab.h_shipped b/util/sconfig/sconfig.tab.h_shipped
index cadd847fa4..b556bbad13 100644
--- a/util/sconfig/sconfig.tab.h_shipped
+++ b/util/sconfig/sconfig.tab.h_shipped
@@ -1,4 +1,4 @@
-/* A Bison parser, made by GNU Bison 3.5.1.  */
+/* A Bison parser, made by GNU Bison 3.5.3.  */
 
 /* Bison interface for Yacc-like parsers in C
 
@@ -52,42 +52,45 @@ extern int yydebug;
     CHIP = 258,
     DEVICE = 259,
     REGISTER = 260,
-    BOOL = 261,
-    STATUS = 262,
-    MANDATORY = 263,
-    BUS = 264,
-    RESOURCE = 265,
-    END = 266,
-    EQUALS = 267,
-    HEX = 268,
-    STRING = 269,
-    PCI = 270,
-    PNP = 271,
-    I2C = 272,
-    APIC = 273,
-    CPU_CLUSTER = 274,
-    CPU = 275,
-    DOMAIN = 276,
-    IRQ = 277,
-    DRQ = 278,
-    SLOT_DESC = 279,
-    IO = 280,
-    NUMBER = 281,
-    SUBSYSTEMID = 282,
-    INHERIT = 283,
-    IOAPIC_IRQ = 284,
-    IOAPIC = 285,
-    PCIINT = 286,
-    GENERIC = 287,
-    SPI = 288,
-    USB = 289,
-    MMIO = 290,
-    LPC = 291,
-    ESPI = 292,
-    FW_CONFIG_TABLE = 293,
-    FW_CONFIG_FIELD = 294,
-    FW_CONFIG_OPTION = 295,
-    FW_CONFIG_PROBE = 296
+    ALIAS = 261,
+    REFERENCE = 262,
+    ASSOCIATION = 263,
+    BOOL = 264,
+    STATUS = 265,
+    MANDATORY = 266,
+    BUS = 267,
+    RESOURCE = 268,
+    END = 269,
+    EQUALS = 270,
+    HEX = 271,
+    STRING = 272,
+    PCI = 273,
+    PNP = 274,
+    I2C = 275,
+    APIC = 276,
+    CPU_CLUSTER = 277,
+    CPU = 278,
+    DOMAIN = 279,
+    IRQ = 280,
+    DRQ = 281,
+    SLOT_DESC = 282,
+    IO = 283,
+    NUMBER = 284,
+    SUBSYSTEMID = 285,
+    INHERIT = 286,
+    IOAPIC_IRQ = 287,
+    IOAPIC = 288,
+    PCIINT = 289,
+    GENERIC = 290,
+    SPI = 291,
+    USB = 292,
+    MMIO = 293,
+    LPC = 294,
+    ESPI = 295,
+    FW_CONFIG_TABLE = 296,
+    FW_CONFIG_FIELD = 297,
+    FW_CONFIG_OPTION = 298,
+    FW_CONFIG_PROBE = 299
   };
 #endif
 
diff --git a/util/sconfig/sconfig.y b/util/sconfig/sconfig.y
index 57e939d9f0..d441ff812d 100755
--- a/util/sconfig/sconfig.y
+++ b/util/sconfig/sconfig.y
@@ -19,11 +19,11 @@ static struct fw_config_field *cur_field;
 	int number;
 }
 
-%token CHIP DEVICE REGISTER BOOL STATUS MANDATORY BUS RESOURCE END EQUALS HEX STRING PCI PNP I2C APIC CPU_CLUSTER CPU DOMAIN IRQ DRQ SLOT_DESC IO NUMBER SUBSYSTEMID INHERIT IOAPIC_IRQ IOAPIC PCIINT GENERIC SPI USB MMIO LPC ESPI FW_CONFIG_TABLE FW_CONFIG_FIELD FW_CONFIG_OPTION FW_CONFIG_PROBE
+%token CHIP DEVICE REGISTER ALIAS REFERENCE ASSOCIATION BOOL STATUS MANDATORY BUS RESOURCE END EQUALS HEX STRING PCI PNP I2C APIC CPU_CLUSTER CPU DOMAIN IRQ DRQ SLOT_DESC IO NUMBER SUBSYSTEMID INHERIT IOAPIC_IRQ IOAPIC PCIINT GENERIC SPI USB MMIO LPC ESPI FW_CONFIG_TABLE FW_CONFIG_FIELD FW_CONFIG_OPTION FW_CONFIG_PROBE
 %%
 devtree: { cur_parent = root_parent; } | devtree chip | devtree fw_config_table;
 
-chipchildren: chipchildren device | chipchildren chip | chipchildren registers | /* empty */ ;
+chipchildren: chipchildren device | chipchildren chip | chipchildren registers | chipchildren reference | /* empty */ ;
 
 devicechildren: devicechildren device | devicechildren chip | devicechildren resource | devicechildren subsystemid | devicechildren ioapic_irq | devicechildren smbios_slot_desc | devicechildren registers | devicechildren fw_config_probe | /* empty */ ;
 
@@ -36,12 +36,18 @@ chip: CHIP STRING /* == path */ {
 	cur_chip_instance = chip_dequeue_tail();
 };
 
-device: DEVICE BUS NUMBER /* == devnum */ status {
-	$<dev>$ = new_device(cur_parent, cur_chip_instance, $<number>2, $<string>3, $<number>4);
+device: DEVICE BUS NUMBER /* == devnum */ alias status {
+	$<dev>$ = new_device(cur_parent, cur_chip_instance, $<number>2, $<string>3, $<string>4, $<number>5);
 	cur_parent = $<dev>$->last_bus;
 }
 	devicechildren END {
-	cur_parent = $<dev>5->parent;
+	cur_parent = $<dev>6->parent;
+};
+
+alias: /* empty */ {
+	$<string>$ = NULL;
+} | ALIAS STRING {
+	$<string>$ = $<string>2;
 };
 
 status: BOOL | STATUS ;
@@ -49,6 +55,9 @@ status: BOOL | STATUS ;
 resource: RESOURCE NUMBER /* == resnum */ EQUALS NUMBER /* == resval */
 	{ add_resource(cur_parent, $<number>1, strtol($<string>2, NULL, 0), strtol($<string>4, NULL, 0)); } ;
 
+reference: REFERENCE STRING /* == alias */ ASSOCIATION STRING /* == field in chip config */
+	{ add_reference(cur_chip_instance, $<string>4, $<string>2); } ;
+
 registers: REGISTER STRING /* == regname */ EQUALS STRING /* == regval */
 	{ add_register(cur_chip_instance, $<string>2, $<string>4); } ;