From 03f11f03dbfe37c0bff2768b8f2e277a29ac62b9 Mon Sep 17 00:00:00 2001
From: Atish Patra <atish.patra@wdc.com>
Date: Thu, 27 Jun 2019 12:53:00 -0700
Subject: [PATCH] RISC-V: Parse cpu topology during boot.
Currently, there are no topology defined for RISC-V.
Parse the cpu-map node from device tree and setup the
cpu topology.
CPU topology after applying the patch.
$cat /sys/devices/system/cpu/cpu2/topology/core_siblings_list
0-3
$cat /sys/devices/system/cpu/cpu3/topology/core_siblings_list
0-3
$cat /sys/devices/system/cpu/cpu3/topology/physical_package_id
0
$cat /sys/devices/system/cpu/cpu3/topology/core_id
3
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
---
arch/riscv/Kconfig | 1 +
arch/riscv/kernel/smpboot.c | 3 +++
2 files changed, 4 insertions(+)
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 59a4727ecd6c0..86ee362a13756 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -48,6 +48,7 @@ config RISCV
select PCI_MSI if PCI
select RISCV_TIMER
select GENERIC_IRQ_MULTI_HANDLER
+ select GENERIC_ARCH_TOPOLOGY if SMP
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_MMIOWB
select HAVE_EBPF_JIT if 64BIT
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index 7462a44304feb..18ae6da5115e5 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -8,6 +8,7 @@
* Copyright (C) 2017 SiFive
*/
+#include <linux/arch_topology.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
@@ -35,6 +36,7 @@ static DECLARE_COMPLETION(cpu_running);
void __init smp_prepare_boot_cpu(void)
{
+ init_cpu_topology();
}
void __init smp_prepare_cpus(unsigned int max_cpus)
@@ -138,6 +140,7 @@ asmlinkage void __init smp_callin(void)
trap_init();
notify_cpu_starting(smp_processor_id());
+ update_siblings_masks(smp_processor_id());
set_cpu_online(smp_processor_id(), 1);
/*
* Remote TLB flushes are ignored while the CPU is offline, so emit
--
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