diff options
Diffstat (limited to 'include/linux/kconfig.h')
| -rw-r--r-- | include/linux/kconfig.h | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h new file mode 100644 index 00000000000..ec9584b2426 --- /dev/null +++ b/include/linux/kconfig.h @@ -0,0 +1,158 @@ +#ifndef __LINUX_KCONFIG_H +#define __LINUX_KCONFIG_H + +#include <generated/autoconf.h> + +/* + * Helper macros to use CONFIG_ options in C/CPP expressions. Note that + * these only work with boolean and tristate options. + */ + +/* + * Getting something that works in C and CPP for an arg that may or may + * not be defined is tricky. Here, if we have "#define CONFIG_BOOGER 1" + * we match on the placeholder define, insert the "0," for arg1 and generate + * the triplet (0, 1, 0). Then the last step cherry picks the 2nd arg (a one). + * When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when + * the last step cherry picks the 2nd arg, we get a zero. + */ +#define __ARG_PLACEHOLDER_1 0, +#define config_enabled(cfg, def_val) _config_enabled(cfg, def_val) +#define _config_enabled(value, def_val) __config_enabled(__ARG_PLACEHOLDER_##value, def_val) +#define __config_enabled(arg1_or_junk, def_val) ___config_enabled(arg1_or_junk 1, def_val) +#define ___config_enabled(__ignored, val, ...) val + +/* + * IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', + * 0 otherwise. + */ +#define IS_ENABLED(option) config_enabled(option, 0) + +/* + * U-Boot add-on: Helper macros to reference to different macros (prefixed by + * CONFIG_, CONFIG_SPL_, CONFIG_TPL_ or CONFIG_TOOLS_), depending on the build + * context. + */ + +#ifdef USE_HOSTCC +#define _CONFIG_PREFIX TOOLS_ +#elif defined(CONFIG_TPL_BUILD) +#define _CONFIG_PREFIX TPL_ +#elif defined(CONFIG_VPL_BUILD) +#define _CONFIG_PREFIX VPL_ +#elif defined(CONFIG_SPL_BUILD) +#define _CONFIG_PREFIX SPL_ +#else +#define _CONFIG_PREFIX +#endif + +#define config_val(cfg) _config_val(_CONFIG_PREFIX, cfg) +#define _config_val(pfx, cfg) __config_val(pfx, cfg) +#define __config_val(pfx, cfg) CONFIG_ ## pfx ## cfg + +/* + * CONFIG_VAL(FOO) evaluates to the value of + * CONFIG_TOOLS_FOO if USE_HOSTCC is defined, + * CONFIG_FOO if CONFIG_XPL_BUILD is undefined, + * CONFIG_SPL_FOO if CONFIG_SPL_BUILD is defined. + * CONFIG_TPL_FOO if CONFIG_TPL_BUILD is defined. + * CONFIG_VPL_FOO if CONFIG_VPL_BUILD is defined. + */ +#define CONFIG_VAL(option) config_val(option) + +/* + * This uses a similar mechanism to config_enabled() above. If cfg is enabled, + * it resolves to the value of opt_cfg, otherwise it resolves to def_val + */ +#define config_opt_enabled(cfg, opt_cfg, def_val) _config_opt_enabled(cfg, opt_cfg, def_val) +#define _config_opt_enabled(cfg_val, opt_value, def_val) \ + __config_opt_enabled(__ARG_PLACEHOLDER_##cfg_val, opt_value, def_val) +#define __config_opt_enabled(arg1_or_junk, arg2, def_val) \ + ___config_opt_enabled(arg1_or_junk arg2, def_val) +#define ___config_opt_enabled(__ignored, val, ...) val + +#ifndef __ASSEMBLY__ +/* + * Detect usage of a the value when the conditional is not enabled. When used + * in assembly context, this likely produces a assembly error, or hopefully at + * least something recognisable. + */ +long invalid_use_of_IF_ENABLED_INT(void); +#endif + +/* Evaluates to int_option if option is defined, otherwise a build error */ +#define IF_ENABLED_INT(option, int_option) \ + config_opt_enabled(option, int_option, invalid_use_of_IF_ENABLED_INT()) + +/* + * Count number of arguments to a variadic macro. Currently only need + * it for 1, 2 or 3 arguments. + */ +#define __arg6(a1, a2, a3, a4, a5, a6, ...) a6 +#define __count_args(...) __arg6(dummy, ##__VA_ARGS__, 4, 3, 2, 1, 0) + +#define __concat(a, b) ___concat(a, b) +#define ___concat(a, b) a ## b + +#define __unwrap(...) __VA_ARGS__ +#define __unwrap1(case1, case0) __unwrap case1 +#define __unwrap0(case1, case0) __unwrap case0 + +#define __CONFIG_IS_ENABLED_1(option) __CONFIG_IS_ENABLED_3(option, (1), (0)) +#define __CONFIG_IS_ENABLED_2(option, case1) __CONFIG_IS_ENABLED_3(option, case1, ()) +#define __CONFIG_IS_ENABLED_3(option, case1, case0) \ + __concat(__unwrap, config_enabled(CONFIG_VAL(option), 0)) (case1, case0) + +/* + * CONFIG_IS_ENABLED(FOO) expands to + * 1 if USE_HOSTCC is defined and CONFIG_TOOLS_FOO is set to 'y', + * 1 if CONFIG_XPL_BUILD is undefined and CONFIG_FOO is set to 'y', + * 1 if CONFIG_SPL_BUILD is defined and CONFIG_SPL_FOO is set to 'y', + * 1 if CONFIG_TPL_BUILD is defined and CONFIG_TPL_FOO is set to 'y', + * 0 otherwise. + * + * CONFIG_IS_ENABLED(FOO, (abc)) expands to + * abc if USE_HOSTCC is defined and CONFIG_TOOLS_FOO is set to 'y', + * abc if CONFIG_XPL_BUILD is undefined and CONFIG_FOO is set to 'y', + * abc if CONFIG_SPL_BUILD is defined and CONFIG_SPL_FOO is set to 'y', + * abc if CONFIG_TPL_BUILD is defined and CONFIG_TPL_FOO is set to 'y', + * nothing otherwise. + * + * CONFIG_IS_ENABLED(FOO, (abc), (def)) expands to + * abc if USE_HOSTCC is defined and CONFIG_TOOLS_FOO is set to 'y', + * abc if CONFIG_XPL_BUILD is undefined and CONFIG_FOO is set to 'y', + * abc if CONFIG_SPL_BUILD is defined and CONFIG_SPL_FOO is set to 'y', + * abc if CONFIG_TPL_BUILD is defined and CONFIG_TPL_FOO is set to 'y', + * def otherwise. + * + * The optional second and third arguments must be parenthesized; that + * allows one to include a trailing comma, e.g. for use in + * + * CONFIG_IS_ENABLED(ACME, ({.compatible = "acme,frobnozzle"},)) + * + * which adds an entry to the array being defined if CONFIG_ACME (or + * CONFIG_SPL_ACME/CONFIG_TPL_ACME, depending on build context) is + * set, and nothing otherwise. + */ + +#define CONFIG_IS_ENABLED(option, ...) \ + __concat(__CONFIG_IS_ENABLED_, __count_args(option, ##__VA_ARGS__)) (option, ##__VA_ARGS__) + +#ifndef __ASSEMBLY__ +/* + * Detect usage of a the value when the conditional is not enabled. When used + * in assembly context, this likely produces a assembly error, or hopefully at + * least something recognisable. + */ +long invalid_use_of_CONFIG_IF_ENABLED_INT(void); +#endif + +/* + * Evaluates to SPL_/TPL_int_option if SPL_/TPL_/option is not defined, + * otherwise build error + */ +#define CONFIG_IF_ENABLED_INT(option, int_option) \ + CONFIG_IS_ENABLED(option, (CONFIG_VAL(int_option)), \ + (invalid_use_of_CONFIG_IF_ENABLED_INT())) + +#endif /* __LINUX_KCONFIG_H */ |