/* SPDX-License-Identifier: GPL-2.0-only */

#ifndef _X86_MP_H_
#define _X86_MP_H_

#include <cpu/x86/smm.h>
#include <types.h>

#define CACHELINE_SIZE 64

struct cpu_info;
struct bus;

static inline void mfence(void)
{
	/* mfence came with the introduction of SSE2. */
	if (CONFIG(SSE2))
		__asm__ __volatile__("mfence\t\n": : :"memory");
	else
		__asm__ __volatile__("lock; addl $0,0(%%esp)": : : "memory");
}

/* The sequence of the callbacks are in calling order. */
struct mp_ops {
	/*
	 * Optionally provide a callback prior to kicking off MP
	 * startup. This callback is done prior to loading the SIPI
	 * vector but after gathering the MP state information. Please
	 * see the sequence below.
	 */
	void (*pre_mp_init)(void);
	/*
	 * Return the number of logical x86 execution contexts that
	 * need to be brought out of SIPI state as well as have SMM
	 * handlers installed.
	 */
	int (*get_cpu_count)(void);
	/*
	 * Optionally fill in permanent SMM region and save state size. If
	 * this callback is not present no SMM handlers will be installed.
	 * The perm_smsize is the size available to house the permanent SMM
	 * handler.
	 */
	void (*get_smm_info)(uintptr_t *perm_smbase, size_t *perm_smsize,
				size_t *smm_save_state_size);
	/*
	 * Optionally fill in pointer to microcode and indicate if the APs
	 * can load the microcode in parallel.
	 */
	void (*get_microcode_info)(const void **microcode, int *parallel);
	/*
	 * Optionally provide a callback prior to the APs starting SMM
	 * relocation or CPU driver initialization. However, note that
	 * this callback is called after SMM handlers have been loaded.
	 */
	void (*pre_mp_smm_init)(void);
	/*
	 * Optional function to use to trigger SMM to perform relocation. If
	 * not provided, smm_initiate_relocation() is used.
	 */
	void (*per_cpu_smm_trigger)(void);
	/*
	 * This function is called while each CPU is in the SMM relocation
	 * handler. Its primary purpose is to adjust the SMBASE for the
	 * permanent handler. The parameters passed are the current cpu
	 * running the relocation handler, current SMBASE of relocation handler,
	 * and the pre-calculated staggered CPU SMBASE address of the permanent
	 * SMM handler.
	 */
	void (*relocation_handler)(int cpu, uintptr_t curr_smbase,
		uintptr_t staggered_smbase);
	/*
	 * Optionally provide a callback that is called after the APs
	 * and the BSP have gone through the initialion sequence.
	 */
	void (*post_mp_init)(void);
};

/*
 * The mp_ops argument is used to drive the multiprocess initialization. Unless
 * otherwise stated each callback is called on the BSP only. The sequence of
 * operations is the following:
 * 1. pre_mp_init()
 * 2. get_cpu_count()
 * 3. get_smm_info()
 * 4. get_microcode_info()
 * 5. adjust_cpu_apic_entry() for each number of get_cpu_count()
 * 6. pre_mp_smm_init()
 * 7. per_cpu_smm_trigger() in parallel for all cpus which calls
 *    relocation_handler() in SMM.
 * 8. mp_initialize_cpu() for each cpu
 * 9. post_mp_init()
 */
enum cb_err mp_init_with_smm(struct bus *cpu_bus, const struct mp_ops *mp_ops);

enum {
	/* Function runs on all cores (both BSP and APs) */
	MP_RUN_ON_ALL_CPUS,
	/* Need to specify cores (only on APs) numbers */
};

/*
 * After APs are up and PARALLEL_MP_AP_WORK is enabled one can issue work
 * to all the APs to perform. Currently the BSP is the only CPU that is allowed
 * to issue work. i.e. the APs should not call any of these functions.
 *
 * Input parameter expire_us <= 0 to specify an infinite timeout.
 * logical_cpu_num = MP_RUN_ON_ALL_CPUS to execute function over all cores (BSP
 * + APs) else specified AP number using logical_cpu_num.
 */
enum cb_err mp_run_on_aps(void (*func)(void *), void *arg, int logical_cpu_num,
		long expire_us);

/*
 * Runs func on all APs excluding BSP, with a provision to run calls in parallel
 * or serially per AP.
 */
enum cb_err mp_run_on_all_aps(void (*func)(void *), void *arg, long expire_us,
			      bool run_parallel);

/* Like mp_run_on_aps() but also runs func on BSP. */
enum cb_err mp_run_on_all_cpus(void (*func)(void *), void *arg);

/* Like mp_run_on_all_cpus but make sure all APs finish executing the
   function call. The time limit on a function call is 1 second. */
enum cb_err mp_run_on_all_cpus_synchronously(void (*func)(void *), void *arg);

/*
 * Park all APs to prepare for OS boot. This is handled automatically
 * by the coreboot infrastructure.
 */
enum cb_err mp_park_aps(void);

/*
 * SMM helpers to use with initializing CPUs.
 */

/* Send SMI to self without any serialization. */
void smm_initiate_relocation_parallel(void);
/* Send SMI to self with single execution. */
void smm_initiate_relocation(void);

#endif /* _X86_MP_H_ */