u-boot/arch/riscv/include/asm/smp.h
Sean Anderson 40686c394e riscv: Clean up IPI initialization code
The previous IPI code initialized the device whenever the first call was
made to a riscv_*_ipi function. This made it difficult to determine when
the IPI device was initialized. This patch introduces a new function
riscv_init_ipi. It is called once during arch_cpu_init_dm. In SPL, it is
called in spl_invoke_opensbi. Before this point, no riscv_*_ipi functions
should be called.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2020-07-01 15:01:22 +08:00

97 lines
2.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2019 Fraunhofer AISEC,
* Lukas Auer <lukas.auer@aisec.fraunhofer.de>
*/
#ifndef _ASM_RISCV_SMP_H
#define _ASM_RISCV_SMP_H
/**
* struct ipi_data - Inter-processor interrupt (IPI) data structure
*
* IPIs are used for SMP support to communicate to other harts what function to
* call. Functions are in the form
* void (*addr)(ulong hart, ulong arg0, ulong arg1).
*
* The function address and the two arguments, arg0 and arg1, are stored in the
* IPI data structure. The hart ID is inserted by the hart handling the IPI and
* calling the function.
*
* @addr: Address of function
* @arg0: First argument of function
* @arg1: Second argument of function
*/
struct ipi_data {
ulong addr;
ulong arg0;
ulong arg1;
};
/**
* handle_ipi() - interrupt handler for software interrupts
*
* The IPI interrupt handler must be called to handle software interrupts. It
* calls the function specified in the hart's IPI data structure.
*
* @hart: Hart ID of the current hart
*/
void handle_ipi(ulong hart);
/**
* smp_call_function() - Call a function on all other harts
*
* Send IPIs with the specified function call to all harts.
*
* @addr: Address of function
* @arg0: First argument of function
* @arg1: Second argument of function
* @wait: Wait for harts to acknowledge request
* @return 0 if OK, -ve on error
*/
int smp_call_function(ulong addr, ulong arg0, ulong arg1, int wait);
/**
* riscv_init_ipi() - Initialize inter-process interrupt (IPI) driver
*
* Platform code must provide this function. This function is called once after
* the cpu driver is initialized. No other riscv_*_ipi() calls will be made
* before this function is called.
*
* @return 0 if OK, -ve on error
*/
int riscv_init_ipi(void);
/**
* riscv_send_ipi() - Send inter-processor interrupt (IPI)
*
* Platform code must provide this function.
*
* @hart: Hart ID of receiving hart
* @return 0 if OK, -ve on error
*/
int riscv_send_ipi(int hart);
/**
* riscv_clear_ipi() - Clear inter-processor interrupt (IPI)
*
* Platform code must provide this function.
*
* @hart: Hart ID of hart to be cleared
* @return 0 if OK, -ve on error
*/
int riscv_clear_ipi(int hart);
/**
* riscv_get_ipi() - Get status of inter-processor interrupt (IPI)
*
* Platform code must provide this function.
*
* @hart: Hart ID of hart to be checked
* @pending: Pointer to variable with result of the check,
* 1 if IPI is pending, 0 otherwise
* @return 0 if OK, -ve on error
*/
int riscv_get_ipi(int hart, int *pending);
#endif