mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-25 20:43:32 +00:00
f760c9a1fd
Some IPIs may already be pending when U-Boot is started. This could be a problem if a secondary hart tries to handle an IPI before the boot hart has initialized the IPI device. To be specific, the Kendryte K210 ROM-based bootloader does not clear IPIs before passing control to U-Boot. Without this patch, the secondary hart jumps to address 0x0 as soon as it enters secondary_hart_loop, and then hangs in its trap handler. This commit introduces a valid bit so secondary harts know when and IPI originates from U-Boot, and it is safe to use the IPI API. The valid bit is initialized to 0 by board_init_f_init_reserve. Before this, secondary harts wait in wait_for_gd_init. Signed-off-by: Sean Anderson <seanga2@gmail.com> Reviewed-by: Bin Meng <bin.meng@windriver.com> Reviewed-by: Rick Chen <rick@andestech.com> Reviewed-by: Leo Liang <ycliang@andestech.com>
104 lines
2.9 KiB
C
104 lines
2.9 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.
|
|
*
|
|
* @valid is used to determine whether a sent IPI originated from U-Boot. It is
|
|
* initialized to zero by board_init_f_alloc_reserve. When U-Boot sends its
|
|
* first IPI, it is set to 1. This prevents already-pending IPIs not sent by
|
|
* U-Boot from being taken.
|
|
*
|
|
* @addr: Address of function
|
|
* @arg0: First argument of function
|
|
* @arg1: Second argument of function
|
|
* @valid: Whether this IPI is valid
|
|
*/
|
|
struct ipi_data {
|
|
ulong addr;
|
|
ulong arg0;
|
|
ulong arg1;
|
|
unsigned int valid;
|
|
};
|
|
|
|
/**
|
|
* 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
|