diff options
Diffstat (limited to 'drivers/acpi/cppc_acpi.c')
| -rw-r--r-- | drivers/acpi/cppc_acpi.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 6f09fe011544..840223c12540 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -100,6 +100,16 @@ static DEFINE_PER_CPU(struct cpc_desc *, cpc_desc_ptr); (cpc)->cpc_entry.reg.space_id == \ ACPI_ADR_SPACE_PLATFORM_COMM) +/* Check if a CPC register is in SystemMemory */ +#define CPC_IN_SYSTEM_MEMORY(cpc) ((cpc)->type == ACPI_TYPE_BUFFER && \ + (cpc)->cpc_entry.reg.space_id == \ + ACPI_ADR_SPACE_SYSTEM_MEMORY) + +/* Check if a CPC register is in SystemIo */ +#define CPC_IN_SYSTEM_IO(cpc) ((cpc)->type == ACPI_TYPE_BUFFER && \ + (cpc)->cpc_entry.reg.space_id == \ + ACPI_ADR_SPACE_SYSTEM_IO) + /* Evaluates to True if reg is a NULL register descriptor */ #define IS_NULL_REG(reg) ((reg)->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY && \ (reg)->address == 0 && \ @@ -1456,6 +1466,9 @@ EXPORT_SYMBOL_GPL(cppc_set_perf); * transition latency for performance change requests. The closest we have * is the timing information from the PCCT tables which provides the info * on the number and frequency of PCC commands the platform can handle. + * + * 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) { @@ -1481,7 +1494,9 @@ unsigned int cppc_get_transition_latency(int cpu_num) return CPUFREQ_ETERNAL; desired_reg = &cpc_desc->cpc_regs[DESIRED_PERF]; - if (!CPC_IN_PCC(desired_reg)) + 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) |