diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index fd25c21cee72..2ae978d27e61 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -42,6 +42,66 @@ */ static struct cppc_cpudata **all_cpu_data; +struct cppc_workaround_oem_info { + char oem_id[ACPI_OEM_ID_SIZE +1]; + char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1]; + u32 oem_revision; +}; + +static bool apply_hisi_workaround; + +static struct cppc_workaround_oem_info wa_info[] = { + { + .oem_id = "HISI ", + .oem_table_id = "HIP07 ", + .oem_revision = 0, + }, { + .oem_id = "HISI ", + .oem_table_id = "HIP08 ", + .oem_revision = 0, + } +}; + +static unsigned int cppc_cpufreq_perf_to_khz(struct cppc_cpudata *cpu, + unsigned int perf); + +/* + * HISI platform does not support delivered performance counter and + * reference performance counter. It can calculate the performance using the + * platform specific mechanism. We reuse the desired performance register to + * store the real performance calculated by the platform. + */ +static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpunum) +{ + struct cppc_cpudata *cpudata = all_cpu_data[cpunum]; + u64 desired_perf; + int ret; + + ret = cppc_get_desired_perf(cpunum, &desired_perf); + if (ret < 0) + return -EIO; + + return cppc_cpufreq_perf_to_khz(cpudata, desired_perf); +} + +static void cppc_check_hisi_workaround(void) +{ + struct acpi_table_header *tbl; + acpi_status status = AE_OK; + int i; + + status = acpi_get_table(ACPI_SIG_PCCT, 0, &tbl); + if (ACPI_FAILURE(status) || !tbl) + return; + + for (i = 0; i < ARRAY_SIZE(wa_info); i++) { + if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) && + !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) && + wa_info[i].oem_revision == tbl->oem_revision) + apply_hisi_workaround = true; + } +} + /* Callback function used to retrieve the max frequency from DMI */ static void cppc_find_dmi_mhz(const struct dmi_header *dm, void *private) { @@ -334,6 +394,9 @@ static unsigned int cppc_cpufreq_get_rate(unsigned int cpunum) struct cppc_cpudata *cpu = all_cpu_data[cpunum]; int ret; + if (apply_hisi_workaround) + return hisi_cppc_cpufreq_get_rate(cpunum); + ret = cppc_get_perf_ctrs(cpunum, &fb_ctrs_t0); if (ret) return ret; @@ -386,6 +449,8 @@ static int __init cppc_cpufreq_init(void) goto out; } + cppc_check_hisi_workaround(); + ret = cpufreq_register_driver(&cppc_cpufreq_driver); if (ret) goto out;