driver inclusion category: feature bugzilla: https://atomgit.com/openeuler/kernel/issues/9163 ---------------------------------------------------------------------- cppc_get_reg_val() and cppc_set_reg_val() combine two responsibilities: looking up the per-CPU cpc_desc and then performing the actual register read/write (including null/optional checks and PCC handling). Split out the register I/O logic into cpc_read_reg() and cpc_write_reg() that accept a struct cpc_register_resource pointer directly. This allows callers that already hold a register reference -- such as the upcoming Resource Priority accessors -- to read or write a register without going through the per-CPU descriptor lookup by index. Also rename the PCC wrappers from cppc_get/set_reg_val_in_pcc() to cpc_read/write_in_pcc() to align with the new naming convention. Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com> Signed-off-by: Hongye Lin <linhongye@h-partners.com> --- drivers/acpi/cppc_acpi.c | 89 ++++++++++++++++++++++++++-------------- 1 file changed, 58 insertions(+), 31 deletions(-) diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 4634ee599fe1..d9e4c39f9152 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -1394,7 +1394,7 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) return ret_val; } -static int cppc_get_reg_val_in_pcc(int cpu, struct cpc_register_resource *reg, u64 *val) +static int cpc_read_in_pcc(int cpu, struct cpc_register_resource *reg, u64 *val) { int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); struct cppc_pcc_data *pcc_ss_data = NULL; @@ -1419,32 +1419,49 @@ static int cppc_get_reg_val_in_pcc(int cpu, struct cpc_register_resource *reg, u return ret; } -static int cppc_get_reg_val(int cpu, enum cppc_regs reg_idx, u64 *val) +/** + * cpc_read_reg - Read value from a register element that may be Integer or Buffer. + * @cpu: CPU number. + * @reg: Pointer to the CPC register element. + * @val: Output value. + * + * Return: 0 on success, -EOPNOTSUPP if null/unsupported, negative on error. + */ +static int cpc_read_reg(int cpu, struct cpc_register_resource *reg, u64 *val) { - struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu); - struct cpc_register_resource *reg; - if (val == NULL) return -EINVAL; - if (!cpc_desc) { - pr_debug("No CPC descriptor for CPU:%d\n", cpu); - return -ENODEV; - } - - reg = &cpc_desc->cpc_regs[reg_idx]; - - if ((reg->type == ACPI_TYPE_INTEGER && reg->optional && - !reg->cpc_entry.int_value) || (reg->type != ACPI_TYPE_INTEGER && - IS_NULL_REG(®->cpc_entry.reg))) { - pr_debug("CPC register is not supported\n"); - return -EOPNOTSUPP; + if (reg->type == ACPI_TYPE_INTEGER) { + if (reg->optional && !reg->cpc_entry.int_value) + goto err_unsupported; + } else if (reg->type == ACPI_TYPE_BUFFER) { + if (IS_NULL_REG(®->cpc_entry.reg)) + goto err_unsupported; + } else { + goto err_unsupported; } if (CPC_IN_PCC(reg)) - return cppc_get_reg_val_in_pcc(cpu, reg, val); + return cpc_read_in_pcc(cpu, reg, val); return cpc_read(cpu, reg, val); + +err_unsupported: + pr_debug("CPC register is not supported\n"); + return -EOPNOTSUPP; +} + +static int cppc_get_reg_val(int cpu, enum cppc_regs reg_idx, u64 *val) +{ + struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu); + + if (!cpc_desc) { + pr_debug("No CPC descriptor for CPU:%d\n", cpu); + return -ENODEV; + } + + return cpc_read_reg(cpu, &cpc_desc->cpc_regs[reg_idx], val); } static bool cppc_desired_perf_readable(const struct cpc_desc *cpc_desc) @@ -1452,7 +1469,7 @@ static bool cppc_desired_perf_readable(const struct cpc_desc *cpc_desc) return cpc_desc->version < CPPC_V4_REV; } -static int cppc_set_reg_val_in_pcc(int cpu, struct cpc_register_resource *reg, u64 val) +static int cpc_write_in_pcc(int cpu, struct cpc_register_resource *reg, u64 val) { int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); struct cppc_pcc_data *pcc_ss_data = NULL; @@ -1477,18 +1494,16 @@ static int cppc_set_reg_val_in_pcc(int cpu, struct cpc_register_resource *reg, u return ret; } -static int cppc_set_reg_val(int cpu, enum cppc_regs reg_idx, u64 val) +/** + * cpc_write_reg - Write a CPC register. + * @cpu: CPU number. + * @reg: Pointer to the CPC register resource. + * @val: Value to write. + * + * Return: 0 on success, negative error code otherwise. + */ +static int cpc_write_reg(int cpu, struct cpc_register_resource *reg, u64 val) { - struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu); - struct cpc_register_resource *reg; - - if (!cpc_desc) { - pr_debug("No CPC descriptor for CPU:%d\n", cpu); - return -ENODEV; - } - - reg = &cpc_desc->cpc_regs[reg_idx]; - /* if a register is writeable, it must be a buffer and not null */ if ((reg->type != ACPI_TYPE_BUFFER) || IS_NULL_REG(®->cpc_entry.reg)) { pr_debug("CPC register is not supported\n"); @@ -1496,11 +1511,23 @@ static int cppc_set_reg_val(int cpu, enum cppc_regs reg_idx, u64 val) } if (CPC_IN_PCC(reg)) - return cppc_set_reg_val_in_pcc(cpu, reg, val); + return cpc_write_in_pcc(cpu, reg, val); return cpc_write(cpu, reg, val); } +static int cppc_set_reg_val(int cpu, enum cppc_regs reg_idx, u64 val) +{ + struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu); + + if (!cpc_desc) { + pr_debug("No CPC descriptor for CPU:%d\n", cpu); + return -ENODEV; + } + + return cpc_write_reg(cpu, &cpc_desc->cpc_regs[reg_idx], val); +} + /** * cppc_get_desired_perf - Get the desired performance register value. * @cpunum: CPU from which to get desired performance. -- 2.33.0