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From:   Ley Foon Tan <leyfoon.tan@starfivetech.com>
To:     Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Albert Ou <aou@eecs.berkeley.edu>
CC:     <linux-riscv@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
        "Ley Foon Tan" <lftan.linux@gmail.com>,
        Conor Dooley <conor.dooley@microchip.com>,
        Andrew Jones <ajones@ventanamicro.com>
Subject: [PATCH v2] riscv: Move call to init_cpu_topology() to later initialization stage
Date:   Thu, 5 Jan 2023 11:37:05 +0800
Message-ID: <20230105033705.3946130-1-leyfoon.tan@starfivetech.com>
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If "capacity-dmips-mhz" is present in a CPU DT node,
topology_parse_cpu_capacity() will fail to allocate memory.
ARM64, with which this code path is shared, does not call
topology_parse_cpu_capacity() until later in boot where memory allocation
is available.

Move init_cpu_topology(), which calls topology_parse_cpu_capacity(), to a
later initialization stage, to match ARM64.

Tested on Qemu platform.

Fixes: 03f11f03dbfe ("RISC-V: Parse cpu topology during boot.")
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Ley Foon Tan <leyfoon.tan@starfivetech.com>

---
Changes:
v2:
- Update commit description with suggestion from Conor.
- Added Reviewed-by.
- Added Fixes.

History:
[v1]: https://patchwork.kernel.org/project/linux-riscv/patch/20230103035316.3841303-1-leyfoon.tan@starfivetech.com/

Conor also submitted patches in [1] to add "capacity-dmips-mhz" DT
parameter for RISC-V platform:

https://patchwork.kernel.org/project/linux-riscv/cover/20230104180513.1379453-1-conor@kernel.org/
---
 arch/riscv/kernel/smpboot.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index 3373df413c88..ddb2afba6d25 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -39,7 +39,6 @@ static DECLARE_COMPLETION(cpu_running);
 
 void __init smp_prepare_boot_cpu(void)
 {
-	init_cpu_topology();
 }
 
 void __init smp_prepare_cpus(unsigned int max_cpus)
@@ -48,6 +47,8 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
 	int ret;
 	unsigned int curr_cpuid;
 
+	init_cpu_topology();
+
 	curr_cpuid = smp_processor_id();
 	store_cpu_topology(curr_cpuid);
 	numa_store_cpu_info(curr_cpuid);
-- 
2.25.1