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From: Atish Patra <atishp@rivosinc.com>
To: linux-kernel@vger.kernel.org
Cc: Atish Patra <atishp@rivosinc.com>,
	Anup Patel <anup@brainfault.org>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Alexandre Ghiti <alexghiti@rivosinc.com>,
	Andrew Jones <ajones@ventanamicro.com>,
	Atish Patra <atishp@atishpatra.org>,
	Conor Dooley <conor.dooley@microchip.com>,
	Guo Ren <guoren@kernel.org>,
	Icenowy Zheng <uwu@icenowy.me>,
	kvm-riscv@lists.infradead.org,
	kvm@vger.kernel.org,
	linux-riscv@lists.infradead.org,
	Mark Rutland <mark.rutland@arm.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Will Deacon <will@kernel.org>
Subject: [v1 04/10] RISC-V: Add SBI PMU snapshot definitions
Date: Mon, 18 Dec 2023 02:41:01 -0800
Message-Id: <20231218104107.2976925-5-atishp@rivosinc.com>
In-Reply-To: <20231218104107.2976925-1-atishp@rivosinc.com>
References: <20231218104107.2976925-1-atishp@rivosinc.com>
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SBI PMU Snapshot function optimizes the number of traps to
higher privilege mode by leveraging a shared memory between the S/VS-mode
and the M/HS mode. Add the definitions for that extension and new error
codes.

Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
---
 arch/riscv/include/asm/sbi.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index f3eeca79a02d..a24bc4fa34ff 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -122,6 +122,7 @@ enum sbi_ext_pmu_fid {
 	SBI_EXT_PMU_COUNTER_STOP,
 	SBI_EXT_PMU_COUNTER_FW_READ,
 	SBI_EXT_PMU_COUNTER_FW_READ_HI,
+	SBI_EXT_PMU_SNAPSHOT_SET_SHMEM,
 };
 
 union sbi_pmu_ctr_info {
@@ -138,6 +139,13 @@ union sbi_pmu_ctr_info {
 	};
 };
 
+/* Data structure to contain the pmu snapshot data */
+struct riscv_pmu_snapshot_data {
+	uint64_t ctr_overflow_mask;
+	uint64_t ctr_values[64];
+	uint64_t reserved[447];
+};
+
 #define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(47, 0)
 #define RISCV_PMU_RAW_EVENT_IDX 0x20000
 
@@ -234,9 +242,11 @@ enum sbi_pmu_ctr_type {
 
 /* Flags defined for counter start function */
 #define SBI_PMU_START_FLAG_SET_INIT_VALUE (1 << 0)
+#define SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT BIT(1)
 
 /* Flags defined for counter stop function */
 #define SBI_PMU_STOP_FLAG_RESET (1 << 0)
+#define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT BIT(1)
 
 enum sbi_ext_dbcn_fid {
 	SBI_EXT_DBCN_CONSOLE_WRITE = 0,
@@ -259,6 +269,7 @@ enum sbi_ext_dbcn_fid {
 #define SBI_ERR_ALREADY_AVAILABLE -6
 #define SBI_ERR_ALREADY_STARTED -7
 #define SBI_ERR_ALREADY_STOPPED -8
+#define SBI_ERR_NO_SHMEM	-9
 
 extern unsigned long sbi_spec_version;
 struct sbiret {
-- 
2.34.1