[PATCH v2 02/27] riscv: define default value for envcfg

From: Deepak Gupta
Date: Fri Mar 29 2024 - 00:45:54 EST


Defines a base default value for envcfg per task. By default all tasks
should have cache zeroing capability. Any future base capabilities that
apply to all tasks can be turned on same way.

Signed-off-by: Deepak Gupta <debug@xxxxxxxxxxxx>
---
arch/riscv/include/asm/csr.h | 2 ++
arch/riscv/kernel/process.c | 1 +
2 files changed, 3 insertions(+)

diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 2468c55933cd..bbd2207adb39 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -202,6 +202,8 @@
#define ENVCFG_CBIE_FLUSH _AC(0x1, UL)
#define ENVCFG_CBIE_INV _AC(0x3, UL)
#define ENVCFG_FIOM _AC(0x1, UL)
+/* by default all threads should be able to zero cache */
+#define ENVCFG_BASE ENVCFG_CBZE

/* Smstateen bits */
#define SMSTATEEN0_AIA_IMSIC_SHIFT 58
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index 92922dbd5b5c..9a85c9d4c902 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -152,6 +152,7 @@ void start_thread(struct pt_regs *regs, unsigned long pc,
else
regs->status |= SR_UXL_64;
#endif
+ current->thread_info.envcfg = ENVCFG_BASE;
}

void flush_thread(void)
--
2.43.2