diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 42f3714f82ab..2198376a6a9c 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -260,6 +260,22 @@ static bool cpc_pcc_write_supported(const struct cpc_register_resource *reg)
 	((((val) & GENMASK(((reg)->bit_width) - 1, 0)) << (reg)->bit_offset) |		\
 	((prev_val) & ~(GENMASK(((reg)->bit_width) - 1, 0) << (reg)->bit_offset)))	\
 
+static bool
+cpc_system_io_write_supported(const struct cpc_register_resource *reg)
+{
+	const struct cpc_reg *gas = &reg->cpc_entry.reg;
+	unsigned int access_width = GET_BIT_WIDTH(gas);
+	u64 access_size;
+
+	if (!IS_ENABLED(CONFIG_HAS_IOPORT) || !CPC_IN_SYSTEM_IO(reg) ||
+	    (access_width != 8 && access_width != 16 && access_width != 32))
+		return false;
+
+	access_size = access_width / 8;
+	return !gas->bit_offset && gas->bit_width == access_width &&
+	       gas->address <= U16_MAX - (access_size - 1) &&
+	       (IS_ENABLED(CONFIG_X86) || IS_ALIGNED(gas->address, access_size));
+}
 static u64 cpc_sysmem_access_size(const struct cpc_register_resource *reg)
 {
 	const struct cpc_reg *gas = &reg->cpc_entry.reg;
@@ -1947,8 +1963,10 @@ int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable)
 	struct cpc_register_resource *auto_sel_reg;
 	struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu);
 	struct cppc_pcc_data *pcc_ss_data = NULL;
-	bool autosel_ffh_sysmem;
-	bool epp_ffh_sysmem;
+	bool auto_sel_pcc;
+	bool auto_sel_non_pcc;
+	bool epp_pcc;
+	bool epp_non_pcc;
 	int ret;
 
 	if (!cpc_desc) {
@@ -1962,52 +1980,74 @@ int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable)
 	    auto_sel_reg->cpc_entry.int_value == 1)
 		return -EOPNOTSUPP;
 
-	epp_ffh_sysmem = CPC_SUPPORTED(epp_set_reg) &&
-		(CPC_IN_FFH(epp_set_reg) || CPC_IN_SYSTEM_MEMORY(epp_set_reg));
-	autosel_ffh_sysmem = CPC_SUPPORTED(auto_sel_reg) &&
-		(CPC_IN_FFH(auto_sel_reg) || CPC_IN_SYSTEM_MEMORY(auto_sel_reg));
+	auto_sel_pcc = cpc_is_writable(auto_sel_reg) &&
+		CPC_IN_PCC(auto_sel_reg);
+	epp_pcc = cpc_is_writable(epp_set_reg) && CPC_IN_PCC(epp_set_reg);
+	if ((auto_sel_pcc && !cpc_pcc_write_supported(auto_sel_reg)) ||
+	    (epp_pcc && !cpc_pcc_write_supported(epp_set_reg)))
+		return -EFAULT;
+	if ((cpc_is_writable(auto_sel_reg) &&
+	     CPC_IN_SYSTEM_IO(auto_sel_reg) &&
+	     !cpc_system_io_write_supported(auto_sel_reg)) ||
+	    (cpc_is_writable(epp_set_reg) && CPC_IN_SYSTEM_IO(epp_set_reg) &&
+	     !cpc_system_io_write_supported(epp_set_reg)))
+		return -EOPNOTSUPP;
 
-	if (CPC_IN_PCC(epp_set_reg) || CPC_IN_PCC(auto_sel_reg)) {
+	auto_sel_non_pcc = cpc_is_writable(auto_sel_reg) && !auto_sel_pcc;
+	epp_non_pcc = cpc_is_writable(epp_set_reg) && !epp_pcc;
+
+	/* Complete fallible non-PCC writes before staging PCC data. */
+	if (auto_sel_non_pcc) {
+		ret = cpc_write(cpu, auto_sel_reg, enable);
+		if (ret)
+			return ret;
+	}
+	if (epp_non_pcc) {
+		ret = cpc_write(cpu, epp_set_reg, perf_ctrls->energy_perf);
+		if (ret)
+			return ret;
+	}
+
+	if (epp_pcc || auto_sel_pcc) {
 		if (pcc_ss_id < 0) {
 			pr_debug("Invalid pcc_ss_id for CPU:%d\n", cpu);
 			return -ENODEV;
 		}
 
-		if (cpc_is_writable(auto_sel_reg)) {
-			ret = cpc_write(cpu, auto_sel_reg, enable);
-			if (ret)
-				return ret;
-		}
-
-		if (cpc_is_writable(epp_set_reg)) {
-			ret = cpc_write(cpu, epp_set_reg, perf_ctrls->energy_perf);
-			if (ret)
-				return ret;
-		}
-
 		pcc_ss_data = pcc_data[pcc_ss_id];
+		if (!pcc_ss_data)
+			return -ENODEV;
 
 		down_write(&pcc_ss_data->pcc_lock);
-		/* after writing CPC, transfer the ownership of PCC to platform */
-		ret = send_pcc_cmd(pcc_ss_id, CMD_WRITE);
-		up_write(&pcc_ss_data->pcc_lock);
-	} else if (osc_cpc_flexible_adr_space_confirmed &&
-		   (epp_ffh_sysmem || autosel_ffh_sysmem)) {
-		if (autosel_ffh_sysmem) {
+
+		ret = check_pcc_chan(pcc_ss_id, false);
+		if (ret)
+			goto out_unlock;
+
+		if (auto_sel_pcc) {
 			ret = cpc_write(cpu, auto_sel_reg, enable);
 			if (ret)
-				return ret;
+				goto out_unlock;
 		}
 
-		if (epp_ffh_sysmem) {
-			ret = cpc_write(cpu, epp_set_reg,
-					perf_ctrls->energy_perf);
+		if (epp_pcc) {
+			ret = cpc_write(cpu, epp_set_reg, perf_ctrls->energy_perf);
 			if (ret)
-				return ret;
+				goto out_unlock;
 		}
+
+		/* after writing CPC, transfer the ownership of PCC to platform */
+		ret = send_pcc_cmd(pcc_ss_id, CMD_WRITE);
+
+out_unlock:
+		if (ret)
+			cppc_abort_pending_pcc_write(pcc_ss_id, pcc_ss_data, ret);
+		up_write(&pcc_ss_data->pcc_lock);
+	} else if (epp_non_pcc || auto_sel_non_pcc) {
+		ret = 0;
 	} else {
-		ret = -ENOTSUPP;
-		pr_debug("_CPC in PCC/FFH/SystemMemory are not supported\n");
+		ret = -EOPNOTSUPP;
+		pr_debug("No writable EPP controls for CPU:%d\n", cpu);
 	}
 
 	return ret;