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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>,
        Marc Zyngier <maz@kernel.org>,
        Daniel Lezcano <daniel.lezcano@linaro.org>
Cc:     Atish Patra <atishp@atishpatra.org>,
        Alistair Francis <Alistair.Francis@wdc.com>,
        Anup Patel <anup@brainfault.org>,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        Anup Patel <apatel@ventanamicro.com>,
        Bin Meng <bmeng.cn@gmail.com>,
        Atish Patra <atishp@rivosinc.com>,
        Palmer Dabbelt <palmer@rivosinc.com>
Subject: [PATCH v18 1/7] RISC-V: Clear SIP bit only when using SBI IPI operations
Date:   Tue, 28 Mar 2023 09:22:17 +0530
Message-Id: <20230328035223.1480939-2-apatel@ventanamicro.com>
In-Reply-To: <20230328035223.1480939-1-apatel@ventanamicro.com>
References: <20230328035223.1480939-1-apatel@ventanamicro.com>
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The software interrupt pending (i.e. [M|S]SIP) bit is writeable for
S-mode but read-only for M-mode so we clear this bit only when using
SBI IPI operations.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/riscv/kernel/sbi.c | 8 +++++++-
 arch/riscv/kernel/smp.c | 2 --
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
index 5c87db8fdff2..ac99a70ead6a 100644
--- a/arch/riscv/kernel/sbi.c
+++ b/arch/riscv/kernel/sbi.c
@@ -646,8 +646,14 @@ static void sbi_send_cpumask_ipi(const struct cpumask *target)
 	sbi_send_ipi(target);
 }
 
+static void sbi_ipi_clear(void)
+{
+	csr_clear(CSR_IP, IE_SIE);
+}
+
 static const struct riscv_ipi_ops sbi_ipi_ops = {
-	.ipi_inject = sbi_send_cpumask_ipi
+	.ipi_inject = sbi_send_cpumask_ipi,
+	.ipi_clear = sbi_ipi_clear
 };
 
 void __init sbi_init(void)
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 8c3b59f1f9b8..8a12768c09ee 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -112,8 +112,6 @@ void riscv_clear_ipi(void)
 {
 	if (ipi_ops && ipi_ops->ipi_clear)
 		ipi_ops->ipi_clear();
-
-	csr_clear(CSR_IP, IE_SIE);
 }
 EXPORT_SYMBOL_GPL(riscv_clear_ipi);
 
-- 
2.34.1