#ifndef _IPXE_MP_H
#define _IPXE_MP_H
/** @file
*
* Multiprocessor functions
*
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#include <stdint.h>
#include <ipxe/api.h>
#include <config/defaults.h>
/**
* An address within the address space for a multiprocessor function
*
* Application processors may be started in a different address space
* from the normal iPXE runtime environment. For example: under
* legacy BIOS the application processors will use flat 32-bit
* physical addressing (with no paging or virtual address offset).
*/
typedef unsigned long mp_addr_t;
/** A multiprocessor function
*
* @v opaque Opaque data pointer
* @v cpuid CPU identifier
*
* iPXE does not set up a normal multiprocessor environment. In
* particular, there is no support for dispatching code to individual
* processors and there is no per-CPU stack allocation.
*
* Multiprocessor code must be prepared to run wth no stack space (and
* with a zero stack pointer). Functions may use the CPU identifier
* to construct a pointer to per-CPU result storage.
*
* Multiprocessor functions are permitted to overwrite all registers
* apart from the stack pointer. On exit, the function should check
* the stack pointer value: if zero then the function should halt the
* CPU, if non-zero then the function should return in the normal way.
*
* Multiprocessor functions do not have access to any capabilities
* typically provided by the firmware: they cannot, for example, write
* any console output.
*
* All parameters are passed in registers, since there may be no stack
* available. These functions cannot be called directly from C code.
*/
typedef void ( mp_func_t ) ( mp_addr_t opaque, unsigned int cpuid );
/**
* Call a multiprocessor function from C code on the current CPU
*
* @v func Multiprocessor function
* @v opaque Opaque data pointer
*
* This function must be provided for each CPU architecture to bridge
* the normal C ABI to the iPXE multiprocessor function ABI. It must
* therefore preserve any necessary registers, determine the CPU
* identifier, call the multiprocessor function (which may destroy any
* registers other than the stack pointer), restore registers, and
* return to the C caller.
*
* This function must be called from within the multiprocessor address
* space (e.g. with flat 32-bit physical addressing for BIOS). It can
* be called directly from C code if the multiprocessor address space
* is identical to the address space used for C code (e.g. under EFI,
* where everything uses flat physical addresses).
*/
extern void __asmcall mp_call ( mp_addr_t func, mp_addr_t opaque );
/**
* Calculate static inline multiprocessor API function name
*
* @v _prefix Subsystem prefix
* @v _api_func API function
* @ret _subsys_func Subsystem API function
*/
#define MPAPI_INLINE( _subsys, _api_func ) \
SINGLE_API_INLINE ( MPAPI_PREFIX_ ## _subsys, _api_func )
/**
* Provide a multiprocessor API implementation
*
* @v _prefix Subsystem prefix
* @v _api_func API function
* @v _func Implementing function
*/
#define PROVIDE_MPAPI( _subsys, _api_func, _func ) \
PROVIDE_SINGLE_API ( MPAPI_PREFIX_ ## _subsys, _api_func, _func )
/**
* Provide a static inline multiprocessor API implementation
*
* @v _prefix Subsystem prefix
* @v _api_func API function
*/
#define PROVIDE_MPAPI_INLINE( _subsys, _api_func ) \
PROVIDE_SINGLE_API_INLINE ( MPAPI_PREFIX_ ## _subsys, _api_func )
/* Include all architecture-independent multiprocessor API headers */
#include <ipxe/null_mp.h>
#include <ipxe/efi/efi_mp.h>
/* Include all architecture-dependent multiprocessor API headers */
#include <bits/mp.h>
/**
* Calculate address as seen by a multiprocessor function
*
* @v address Address in normal iPXE address space
* @ret address Address in application processor address space
*/
mp_addr_t mp_address ( void *address );
/**
* Execute a multiprocessor function on the boot processor
*
* @v func Multiprocessor function
* @v opaque Opaque data pointer
*
* This is a blocking operation: the call will return only when the
* multiprocessor function exits.
*/
void mp_exec_boot ( mp_func_t func, void *opaque );
/**
* Start a multiprocessor function on all application processors
*
* @v func Multiprocessor function
* @v opaque Opaque data pointer
*
* This is a non-blocking operation: it is the caller's responsibility
* to provide a way to determine when the multiprocessor function has
* finished executing and halted its CPU.
*/
void mp_start_all ( mp_func_t func, void *opaque );
/**
* Update maximum observed CPU identifier
*
* @v opaque Opaque data pointer
* @v cpuid CPU identifier
*
* This may be invoked on each processor to update a shared maximum
* CPU identifier value.
*/
extern mp_func_t mp_update_max_cpuid;
extern unsigned int mp_boot_cpuid ( void );
extern unsigned int mp_max_cpuid ( void );
#endif /* _IPXE_MP_H */
