mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-01-23 16:53:58 -05:00
Code Activity

riscv: Save/restore envcfg CSR during CPU suspend

Browse source 
The value of the [ms]envcfg CSR is lost when entering a nonretentive
idle state, so the CSR must be rewritten when resuming the CPU.

Cc: <stable@vger.kernel.org> # v6.7+
Fixes: 43c16d51a1 ("RISC-V: Enable cbo.zero in usermode")
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20240228065559.3434837-4-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit is contained in:
Samuel Holland 2024-02-27 22:55:35 -08:00 • committed by Palmer Dabbelt
parent 4774848fef
commit 05ab803d1a
No known key found for this signature in database
GPG key ID: 2E1319F35FBB1889
2 changed files with 5 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
arch/riscv/include/asm/suspend.h
View file

@ -14,6 +14,7 @@ struct suspend_context {
struct pt_regs regs;
/* Saved and restored by high-level functions */
unsigned long scratch;
unsigned long envcfg;
unsigned long tvec;
unsigned long ie;
#ifdef CONFIG_MMU

4
arch/riscv/kernel/suspend.c
View file

@ -15,6 +15,8 @@
void suspend_save_csrs(struct suspend_context *context)
{
context->scratch = csr_read(CSR_SCRATCH);
if (riscv_cpu_has_extension_unlikely(smp_processor_id(), RISCV_ISA_EXT_XLINUXENVCFG))
context->envcfg = csr_read(CSR_ENVCFG);
context->tvec = csr_read(CSR_TVEC);
context->ie = csr_read(CSR_IE);
@ -36,6 +38,8 @@ void suspend_save_csrs(struct suspend_context *context)
void suspend_restore_csrs(struct suspend_context *context)
{
csr_write(CSR_SCRATCH, context->scratch);
if (riscv_cpu_has_extension_unlikely(smp_processor_id(), RISCV_ISA_EXT_XLINUXENVCFG))
csr_write(CSR_ENVCFG, context->envcfg);
csr_write(CSR_TVEC, context->tvec);
csr_write(CSR_IE, context->ie);