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From:   Anup Patel <apatel@ventanamicro.com>
To:     Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Frank Rowand <frowand.list@gmail.com>
Cc:     Conor Dooley <conor+dt@kernel.org>, Marc Zyngier <maz@kernel.org>,
        =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= <bjorn@kernel.org>,
        Atish Patra <atishp@atishpatra.org>,
        Andrew Jones <ajones@ventanamicro.com>,
        Sunil V L <sunilvl@ventanamicro.com>,
        Saravana Kannan <saravanak@google.com>,
        Anup Patel <anup@brainfault.org>,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, Anup Patel <apatel@ventanamicro.com>,
        Atish Patra <atishp@rivosinc.com>
Subject: [PATCH v2 1/2] RISC-V: Don't fail in riscv_of_parent_hartid() for disabled HARTs
Date:   Fri, 27 Oct 2023 21:12:53 +0530
Message-Id: <20231027154254.355853-2-apatel@ventanamicro.com>
In-Reply-To: <20231027154254.355853-1-apatel@ventanamicro.com>
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The riscv_of_processor_hartid() used by riscv_of_parent_hartid() fails
for HARTs disabled in the DT. This results in the following warning
thrown by the RISC-V INTC driver for the E-core on SiFive boards:

[    0.000000] riscv-intc: unable to find hart id for /cpus/cpu@0/interrupt-controller

The riscv_of_parent_hartid() is only expected to read the hartid
from the DT so we directly call of_get_cpu_hwid() instead of calling
riscv_of_processor_hartid().

Fixes: ad635e723e17 ("riscv: cpu: Add 64bit hartid support on RV64")
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
---
 arch/riscv/kernel/cpu.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index c17dacb1141c..157ace8b262c 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -125,13 +125,14 @@ int __init riscv_early_of_processor_hartid(struct device_node *node, unsigned lo
  */
 int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid)
 {
-	int rc;
-
 	for (; node; node = node->parent) {
 		if (of_device_is_compatible(node, "riscv")) {
-			rc = riscv_of_processor_hartid(node, hartid);
-			if (!rc)
-				return 0;
+			*hartid = (unsigned long)of_get_cpu_hwid(node, 0);
+			if (*hartid == ~0UL) {
+				pr_warn("Found CPU without hart ID\n");
+				return -ENODEV;
+			}
+			return 0;
 		}
 	}
 
-- 
2.34.1