diff options
Diffstat (limited to 'arch/riscv/lib')
| -rw-r--r-- | arch/riscv/lib/Makefile | 1 | ||||
| -rw-r--r-- | arch/riscv/lib/smp.c | 118 |
2 files changed, 119 insertions, 0 deletions
diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile index edfa61690c7..19370f97497 100644 --- a/arch/riscv/lib/Makefile +++ b/arch/riscv/lib/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_SIFIVE_CLINT) += sifive_clint.o obj-y += interrupts.o obj-y += reset.o obj-y += setjmp.o +obj-$(CONFIG_SMP) += smp.o # For building EFI apps CFLAGS_$(EFI_CRT0) := $(CFLAGS_EFI) diff --git a/arch/riscv/lib/smp.c b/arch/riscv/lib/smp.c new file mode 100644 index 00000000000..caa292ccd20 --- /dev/null +++ b/arch/riscv/lib/smp.c @@ -0,0 +1,118 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2019 Fraunhofer AISEC, + * Lukas Auer <lukas.auer@aisec.fraunhofer.de> + */ + +#include <common.h> +#include <dm.h> +#include <asm/barrier.h> +#include <asm/smp.h> + +DECLARE_GLOBAL_DATA_PTR; + +/** + * 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 + */ +extern 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 + */ +extern int riscv_clear_ipi(int hart); + +static int send_ipi_many(struct ipi_data *ipi) +{ + ofnode node, cpus; + u32 reg; + int ret; + + cpus = ofnode_path("/cpus"); + if (!ofnode_valid(cpus)) { + pr_err("Can't find cpus node!\n"); + return -EINVAL; + } + + ofnode_for_each_subnode(node, cpus) { + /* skip if hart is marked as not available in the device tree */ + if (!ofnode_is_available(node)) + continue; + + /* read hart ID of CPU */ + ret = ofnode_read_u32(node, "reg", ®); + if (ret) + continue; + + /* skip if it is the hart we are running on */ + if (reg == gd->arch.boot_hart) + continue; + + if (reg >= CONFIG_NR_CPUS) { + pr_err("Hart ID %d is out of range, increase CONFIG_NR_CPUS\n", + reg); + continue; + } + + /* skip if hart is not available */ + if (!(gd->arch.available_harts & (1 << reg))) + continue; + + gd->arch.ipi[reg].addr = ipi->addr; + gd->arch.ipi[reg].arg0 = ipi->arg0; + gd->arch.ipi[reg].arg1 = ipi->arg1; + + ret = riscv_send_ipi(reg); + if (ret) { + pr_err("Cannot send IPI to hart %d\n", reg); + return ret; + } + } + + return 0; +} + +void handle_ipi(ulong hart) +{ + int ret; + void (*smp_function)(ulong hart, ulong arg0, ulong arg1); + + if (hart >= CONFIG_NR_CPUS) + return; + + ret = riscv_clear_ipi(hart); + if (ret) { + pr_err("Cannot clear IPI of hart %ld\n", hart); + return; + } + + __smp_mb(); + + smp_function = (void (*)(ulong, ulong, ulong))gd->arch.ipi[hart].addr; + invalidate_icache_all(); + + smp_function(hart, gd->arch.ipi[hart].arg0, gd->arch.ipi[hart].arg1); +} + +int smp_call_function(ulong addr, ulong arg0, ulong arg1) +{ + int ret = 0; + struct ipi_data ipi; + + ipi.addr = addr; + ipi.arg0 = arg0; + ipi.arg1 = arg1; + + ret = send_ipi_many(&ipi); + + return ret; +} |