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Diffstat (limited to 'arch/riscv/kernel/suspend.c')
-rw-r--r--arch/riscv/kernel/suspend.c70
1 files changed, 66 insertions, 4 deletions
diff --git a/arch/riscv/kernel/suspend.c b/arch/riscv/kernel/suspend.c
index 299795341e8a..24b3f57d467f 100644
--- a/arch/riscv/kernel/suspend.c
+++ b/arch/riscv/kernel/suspend.c
@@ -14,8 +14,7 @@
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))
+ if (riscv_has_extension_unlikely(RISCV_ISA_EXT_XLINUXENVCFG))
context->envcfg = csr_read(CSR_ENVCFG);
context->tvec = csr_read(CSR_TVEC);
context->ie = csr_read(CSR_IE);
@@ -31,19 +30,33 @@ void suspend_save_csrs(struct suspend_context *context)
*/
#ifdef CONFIG_MMU
+ if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SSTC)) {
+ context->stimecmp = csr_read(CSR_STIMECMP);
+#if __riscv_xlen < 64
+ context->stimecmph = csr_read(CSR_STIMECMPH);
+#endif
+ }
+
context->satp = csr_read(CSR_SATP);
#endif
}
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_SCRATCH, 0);
+ if (riscv_has_extension_unlikely(RISCV_ISA_EXT_XLINUXENVCFG))
csr_write(CSR_ENVCFG, context->envcfg);
csr_write(CSR_TVEC, context->tvec);
csr_write(CSR_IE, context->ie);
#ifdef CONFIG_MMU
+ if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SSTC)) {
+ csr_write(CSR_STIMECMP, context->stimecmp);
+#if __riscv_xlen < 64
+ csr_write(CSR_STIMECMPH, context->stimecmph);
+#endif
+ }
+
csr_write(CSR_SATP, context->satp);
#endif
}
@@ -132,4 +145,53 @@ static int __init sbi_system_suspend_init(void)
}
arch_initcall(sbi_system_suspend_init);
+
+static int sbi_suspend_finisher(unsigned long suspend_type,
+ unsigned long resume_addr,
+ unsigned long opaque)
+{
+ struct sbiret ret;
+
+ ret = sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_SUSPEND,
+ suspend_type, resume_addr, opaque, 0, 0, 0);
+
+ return (ret.error) ? sbi_err_map_linux_errno(ret.error) : 0;
+}
+
+int riscv_sbi_hart_suspend(u32 state)
+{
+ if (state & SBI_HSM_SUSP_NON_RET_BIT)
+ return cpu_suspend(state, sbi_suspend_finisher);
+ else
+ return sbi_suspend_finisher(state, 0, 0);
+}
+
+bool riscv_sbi_suspend_state_is_valid(u32 state)
+{
+ if (state > SBI_HSM_SUSPEND_RET_DEFAULT &&
+ state < SBI_HSM_SUSPEND_RET_PLATFORM)
+ return false;
+
+ if (state > SBI_HSM_SUSPEND_NON_RET_DEFAULT &&
+ state < SBI_HSM_SUSPEND_NON_RET_PLATFORM)
+ return false;
+
+ return true;
+}
+
+bool riscv_sbi_hsm_is_supported(void)
+{
+ /*
+ * The SBI HSM suspend function is only available when:
+ * 1) SBI version is 0.3 or higher
+ * 2) SBI HSM extension is available
+ */
+ if (sbi_spec_version < sbi_mk_version(0, 3) ||
+ !sbi_probe_extension(SBI_EXT_HSM)) {
+ pr_info("HSM suspend not available\n");
+ return false;
+ }
+
+ return true;
+}
#endif /* CONFIG_RISCV_SBI */