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path: root/drivers/acpi/cppc_acpi.c
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Diffstat (limited to 'drivers/acpi/cppc_acpi.c')
-rw-r--r--drivers/acpi/cppc_acpi.c16
1 files changed, 7 insertions, 9 deletions
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 6b649031808f..ab4651205e8a 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -1876,7 +1876,7 @@ EXPORT_SYMBOL_GPL(cppc_set_perf);
* If desired_reg is in the SystemMemory or SystemIo ACPI address space,
* then assume there is no latency.
*/
-unsigned int cppc_get_transition_latency(int cpu_num)
+int cppc_get_transition_latency(int cpu_num)
{
/*
* Expected transition latency is based on the PCCT timing values
@@ -1889,31 +1889,29 @@ unsigned int cppc_get_transition_latency(int cpu_num)
* completion of a command before issuing the next command,
* in microseconds.
*/
- unsigned int latency_ns = 0;
struct cpc_desc *cpc_desc;
struct cpc_register_resource *desired_reg;
int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu_num);
struct cppc_pcc_data *pcc_ss_data;
+ int latency_ns = 0;
cpc_desc = per_cpu(cpc_desc_ptr, cpu_num);
if (!cpc_desc)
- return CPUFREQ_ETERNAL;
+ return -ENODATA;
desired_reg = &cpc_desc->cpc_regs[DESIRED_PERF];
if (CPC_IN_SYSTEM_MEMORY(desired_reg) || CPC_IN_SYSTEM_IO(desired_reg))
return 0;
- else if (!CPC_IN_PCC(desired_reg))
- return CPUFREQ_ETERNAL;
- if (pcc_ss_id < 0)
- return CPUFREQ_ETERNAL;
+ if (!CPC_IN_PCC(desired_reg) || pcc_ss_id < 0)
+ return -ENODATA;
pcc_ss_data = pcc_data[pcc_ss_id];
if (pcc_ss_data->pcc_mpar)
latency_ns = 60 * (1000 * 1000 * 1000 / pcc_ss_data->pcc_mpar);
- latency_ns = max(latency_ns, pcc_ss_data->pcc_nominal * 1000);
- latency_ns = max(latency_ns, pcc_ss_data->pcc_mrtt * 1000);
+ latency_ns = max_t(int, latency_ns, pcc_ss_data->pcc_nominal * 1000);
+ latency_ns = max_t(int, latency_ns, pcc_ss_data->pcc_mrtt * 1000);
return latency_ns;
}