diff options
Diffstat (limited to 'arch/x86/include/asm/mp.h')
| -rw-r--r-- | arch/x86/include/asm/mp.h | 137 |
1 files changed, 117 insertions, 20 deletions
diff --git a/arch/x86/include/asm/mp.h b/arch/x86/include/asm/mp.h index 9dddf88b5a..5f9b8c6564 100644 --- a/arch/x86/include/asm/mp.h +++ b/arch/x86/include/asm/mp.h @@ -11,6 +11,17 @@ #include <asm/atomic.h> #include <asm/cache.h> +enum { + /* Indicates that the function should run on all CPUs */ + MP_SELECT_ALL = -1, + + /* Run on boot CPUs */ + MP_SELECT_BSP = -2, + + /* Run on non-boot CPUs */ + MP_SELECT_APS = -3, +}; + typedef int (*mp_callback_t)(struct udevice *cpu, void *arg); /* @@ -25,6 +36,14 @@ typedef int (*mp_callback_t)(struct udevice *cpu, void *arg); * * Note that ap_call() and bsp_call() can be NULL. In the NULL case the * callback will just not be called. + * + * @barrier: Ensures that the BSP and AP don't run the flight record at the same + * time + * @cpus_entered: Counts the number of APs that have run this record + * @ap_call: Function for the APs to call + * @ap_arg: Argument to pass to @ap_call + * @bsp_call: Function for the BSP to call + * @bsp_arg: Argument to pass to @bsp_call */ struct mp_flight_record { atomic_t barrier; @@ -52,21 +71,6 @@ struct mp_flight_record { MP_FLIGHT_RECORD(1, ap_func, ap_arg, bsp_func, bsp_arg) /* - * The mp_params structure provides the arguments to the mp subsystem - * for bringing up APs. - * - * At present this is overkill for U-Boot, but it may make it easier to add - * SMM support. - */ -struct mp_params { - int parallel_microcode_load; - const void *microcode_pointer; - /* Flight plan for APs and BSP */ - struct mp_flight_record *flight_plan; - int num_records; -}; - -/* * mp_init() will set up the SIPI vector and bring up the APs according to * mp_params. Each flight record will be executed according to the plan. Note * that the MP infrastructure uses SMM default area without saving it. It's @@ -85,12 +89,105 @@ struct mp_params { * * mp_init() returns < 0 on error, 0 on success. */ -int mp_init(struct mp_params *params); +int mp_init(void); -/* Probes the CPU device */ -int mp_init_cpu(struct udevice *cpu, void *unused); - -/* Set up additional CPUs */ +/** + * x86_mp_init() - Set up additional CPUs + * + * @returns < 0 on error, 0 on success. + */ int x86_mp_init(void); +/** + * mp_run_func() - Function to call on the AP + * + * @arg: Argument to pass + */ +typedef void (*mp_run_func)(void *arg); + +#if CONFIG_IS_ENABLED(SMP) && !CONFIG_IS_ENABLED(X86_64) +/** + * mp_run_on_cpus() - Run a function on one or all CPUs + * + * This does not return until all CPUs have completed the work + * + * Running on anything other than the boot CPU is only supported if + * CONFIG_SMP_AP_WORK is enabled + * + * @cpu_select: CPU to run on (its dev->req_seq value), or MP_SELECT_ALL for + * all, or MP_SELECT_BSP for BSP + * @func: Function to run + * @arg: Argument to pass to the function + * @return 0 on success, -ve on error + */ +int mp_run_on_cpus(int cpu_select, mp_run_func func, void *arg); + +/** + * mp_park_aps() - Park the APs ready for the OS + * + * This halts all CPUs except the main one, ready for the OS to use them + * + * @return 0 if OK, -ve on error + */ +int mp_park_aps(void); + +/** + * mp_first_cpu() - Get the first CPU to process, from a selection + * + * This is used to iterate through selected CPUs. Call this function first, then + * call mp_next_cpu() repeatedly (with the same @cpu_select) until it returns + * -EFBIG. + * + * @cpu_select: Selected CPUs (either a CPU number or MP_SELECT_...) + * @return next CPU number to run on (e.g. 0) + */ +int mp_first_cpu(int cpu_select); + +/** + * mp_next_cpu() - Get the next CPU to process, from a selection + * + * This is used to iterate through selected CPUs. After first calling + * mp_first_cpu() once, call this function repeatedly until it returns -EFBIG. + * + * The value of @cpu_select must be the same for all calls and must match the + * value passed to mp_first_cpu(), otherwise the behaviour is undefined. + * + * @cpu_select: Selected CPUs (either a CPU number or MP_SELECT_...) + * @prev_cpu: Previous value returned by mp_first_cpu()/mp_next_cpu() + * @return next CPU number to run on (e.g. 0) + */ +int mp_next_cpu(int cpu_select, int prev_cpu); +#else +static inline int mp_run_on_cpus(int cpu_select, mp_run_func func, void *arg) +{ + /* There is only one CPU, so just call the function here */ + func(arg); + + return 0; +} + +static inline int mp_park_aps(void) +{ + /* No APs to park */ + + return 0; +} + +static inline int mp_first_cpu(int cpu_select) +{ + /* We cannot run on any APs, nor a selected CPU */ + return cpu_select == MP_SELECT_APS ? -EFBIG : MP_SELECT_BSP; +} + +static inline int mp_next_cpu(int cpu_select, int prev_cpu) +{ + /* + * When MP is not enabled, there is only one CPU and we did it in + * mp_first_cpu() + */ + return -EFBIG; +} + +#endif + #endif /* _X86_MP_H_ */ |