X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=include%2Facpi%2Factbl3.h;h=8c61b5fe42a48417fb7b9b4080fac0ff743978a4;hb=cd856db69c88db438215244571957d812bdc6813;hp=f65a0ed869ebc327bceee545bbe7d905726b05b4;hpb=89a897fbd8c181bfbf814b84fcdce1cd80a3a388;p=karo-tx-linux.git diff --git a/include/acpi/actbl3.h b/include/acpi/actbl3.h index f65a0ed869eb..8c61b5fe42a4 100644 --- a/include/acpi/actbl3.h +++ b/include/acpi/actbl3.h @@ -75,7 +75,6 @@ /* Reserved table signatures */ #define ACPI_SIG_CSRT "CSRT" /* Core System Resources Table */ -#define ACPI_SIG_DBG2 "DBG2" /* Debug Port table 2 */ #define ACPI_SIG_MATR "MATR" /* Memory Address Translation Table */ #define ACPI_SIG_MSDM "MSDM" /* Microsoft Data Management Table */ #define ACPI_SIG_WPBT "WPBT" /* Windows Platform Binary Table */ @@ -87,9 +86,15 @@ #pragma pack(1) /* - * Note about bitfields: The u8 type is used for bitfields in ACPI tables. - * This is the only type that is even remotely portable. Anything else is not - * portable, so do not use any other bitfield types. + * Note: C bitfields are not used for this reason: + * + * "Bitfields are great and easy to read, but unfortunately the C language + * does not specify the layout of bitfields in memory, which means they are + * essentially useless for dealing with packed data in on-disk formats or + * binary wire protocols." (Or ACPI tables and buffers.) "If you ask me, + * this decision was a design error in C. Ritchie could have picked an order + * and stuck with it." Norman Ramsey. + * See http://stackoverflow.com/a/1053662/41661 */ /*******************************************************************************