1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2019 Fraunhofer AISEC, 4 * Lukas Auer <lukas.auer@aisec.fraunhofer.de> 5 */ 6 7 #ifndef _ASM_RISCV_SMP_H 8 #define _ASM_RISCV_SMP_H 9 10 /** 11 * struct ipi_data - Inter-processor interrupt (IPI) data structure 12 * 13 * IPIs are used for SMP support to communicate to other harts what function to 14 * call. Functions are in the form 15 * void (*addr)(ulong hart, ulong arg0, ulong arg1). 16 * 17 * The function address and the two arguments, arg0 and arg1, are stored in the 18 * IPI data structure. The hart ID is inserted by the hart handling the IPI and 19 * calling the function. 20 * 21 * @valid is used to determine whether a sent IPI originated from U-Boot. It is 22 * initialized to zero by board_init_f_alloc_reserve. When U-Boot sends its 23 * first IPI, it is set to 1. This prevents already-pending IPIs not sent by 24 * U-Boot from being taken. 25 * 26 * @addr: Address of function 27 * @arg0: First argument of function 28 * @arg1: Second argument of function 29 * @valid: Whether this IPI is valid 30 */ 31 struct ipi_data { 32 ulong addr; 33 ulong arg0; 34 ulong arg1; 35 unsigned int valid; 36 }; 37 38 /** 39 * handle_ipi() - interrupt handler for software interrupts 40 * 41 * The IPI interrupt handler must be called to handle software interrupts. It 42 * calls the function specified in the hart's IPI data structure. 43 * 44 * @hart: Hart ID of the current hart 45 */ 46 void handle_ipi(ulong hart); 47 48 /** 49 * smp_call_function() - Call a function on all other harts 50 * 51 * Send IPIs with the specified function call to all harts. 52 * 53 * @addr: Address of function 54 * @arg0: First argument of function 55 * @arg1: Second argument of function 56 * @wait: Wait for harts to acknowledge request 57 * @return 0 if OK, -ve on error 58 */ 59 int smp_call_function(ulong addr, ulong arg0, ulong arg1, int wait); 60 61 /** 62 * riscv_init_ipi() - Initialize inter-process interrupt (IPI) driver 63 * 64 * Platform code must provide this function. This function is called once after 65 * the cpu driver is initialized. No other riscv_*_ipi() calls will be made 66 * before this function is called. 67 * 68 * @return 0 if OK, -ve on error 69 */ 70 int riscv_init_ipi(void); 71 72 /** 73 * riscv_send_ipi() - Send inter-processor interrupt (IPI) 74 * 75 * Platform code must provide this function. 76 * 77 * @hart: Hart ID of receiving hart 78 * @return 0 if OK, -ve on error 79 */ 80 int riscv_send_ipi(int hart); 81 82 /** 83 * riscv_clear_ipi() - Clear inter-processor interrupt (IPI) 84 * 85 * Platform code must provide this function. 86 * 87 * @hart: Hart ID of hart to be cleared 88 * @return 0 if OK, -ve on error 89 */ 90 int riscv_clear_ipi(int hart); 91 92 /** 93 * riscv_get_ipi() - Get status of inter-processor interrupt (IPI) 94 * 95 * Platform code must provide this function. 96 * 97 * @hart: Hart ID of hart to be checked 98 * @pending: Pointer to variable with result of the check, 99 * 1 if IPI is pending, 0 otherwise 100 * @return 0 if OK, -ve on error 101 */ 102 int riscv_get_ipi(int hart, int *pending); 103 104 #endif 105