[PATCH v4 0/2] powernv/cpuidle Device-tree parsing cleanup

[PATCH v4 0/2] powernv/cpuidle Device-tree parsing cleanup

[Akshay Adiga]

Device-tree parsed multiple time in powernv cpuidle and powernv
hotplug code.

First to identify supported flags. Second time, to identify deepest_state
and first deep state. Third time, during cpuidle init to find the available
idle states. Any change in device-tree format will lead to make changes in
these 3 places. Errors in device-tree can be handled in a better manner.

This series adds code to parse device tree once and save in global structure.

Changes from v3 :
 - Removed a stale comment
Changes from v2 :
 - Fix build error (moved a hunk from patch 1 to patch 2)
Changes from v1 :
 - fold first 2 patches into 1
 - rename pm_ctrl_reg_* as psscr_*
 - added comment stating removal of pmicr parsing code
 - removed parsing code for pmicr
 - add member valid in pnv_idle_states_t to indicate if the psscr-mask/val
are valid combination,
 - Change function description of pnv_parse_cpuidle_dt
 - Added error handling code.


Akshay Adiga (2):
  powernv/cpuidle: Parse dt idle properties into global structure
  powernv/cpuidle: Use parsed device tree values for cpuidle_init

 arch/powerpc/include/asm/cpuidle.h    |  13 ++
 arch/powerpc/platforms/powernv/idle.c | 216 ++++++++++++++++----------
 drivers/cpuidle/cpuidle-powernv.c     | 158 ++++---------------
 3 files changed, 177 insertions(+), 210 deletions(-)

-- 
2.18.0.rc2.85.g1fb9df7

[PATCH v4 1/2] powernv/cpuidle: Parse dt idle properties into global structure

[Akshay Adiga]

Device-tree parsing happens twice, once while deciding idle state to be
used for hotplug and once during cpuidle init. Hence, parsing the device
tree and caching it will reduce code duplication. Parsing code has been
moved to pnv_parse_cpuidle_dt() from pnv_probe_idle_states(). In addition
to the properties in the device tree the number of available states is
also required.

Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/cpuidle.h    |  11 ++
 arch/powerpc/platforms/powernv/idle.c | 216 ++++++++++++++++----------
 2 files changed, 149 insertions(+), 78 deletions(-)

diff --git a/arch/powerpc/include/asm/cpuidle.h b/arch/powerpc/include/asm/cpuidle.h
index e210a83eb196..574b0ce1d671 100644
--- a/arch/powerpc/include/asm/cpuidle.h
+++ b/arch/powerpc/include/asm/cpuidle.h
@@ -79,6 +79,17 @@ struct stop_sprs {
 	u64 mmcra;
 };
 
+#define PNV_IDLE_NAME_LEN    16
+struct pnv_idle_states_t {
+	char name[PNV_IDLE_NAME_LEN];
+	u32 latency_ns;
+	u32 residency_ns;
+	u64 psscr_val;
+	u64 psscr_mask;
+	u32 flags;
+	bool valid;
+};
+
 extern u32 pnv_fastsleep_workaround_at_entry[];
 extern u32 pnv_fastsleep_workaround_at_exit[];
 
diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
index 1c5d0675b43c..7cf71b3e03a1 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c
@@ -36,6 +36,8 @@
 #define P9_STOP_SPR_PSSCR      855
 
 static u32 supported_cpuidle_states;
+struct pnv_idle_states_t *pnv_idle_states;
+int nr_pnv_idle_states;
 
 /*
  * The default stop state that will be used by ppc_md.power_save
@@ -622,48 +624,10 @@ int validate_psscr_val_mask(u64 *psscr_val, u64 *psscr_mask, u32 flags)
  * @dt_idle_states: Number of idle state entries
  * Returns 0 on success
  */
-static int __init pnv_power9_idle_init(struct device_node *np, u32 *flags,
-					int dt_idle_states)
+static int __init pnv_power9_idle_init(void)
 {
-	u64 *psscr_val = NULL;
-	u64 *psscr_mask = NULL;
-	u32 *residency_ns = NULL;
 	u64 max_residency_ns = 0;
-	int rc = 0, i;
-
-	psscr_val = kcalloc(dt_idle_states, sizeof(*psscr_val), GFP_KERNEL);
-	psscr_mask = kcalloc(dt_idle_states, sizeof(*psscr_mask), GFP_KERNEL);
-	residency_ns = kcalloc(dt_idle_states, sizeof(*residency_ns),
-			       GFP_KERNEL);
-
-	if (!psscr_val || !psscr_mask || !residency_ns) {
-		rc = -1;
-		goto out;
-	}
-
-	if (of_property_read_u64_array(np,
-		"ibm,cpu-idle-state-psscr",
-		psscr_val, dt_idle_states)) {
-		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr in DT\n");
-		rc = -1;
-		goto out;
-	}
-
-	if (of_property_read_u64_array(np,
-				       "ibm,cpu-idle-state-psscr-mask",
-				       psscr_mask, dt_idle_states)) {
-		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr-mask in DT\n");
-		rc = -1;
-		goto out;
-	}
-
-	if (of_property_read_u32_array(np,
-				       "ibm,cpu-idle-state-residency-ns",
-					residency_ns, dt_idle_states)) {
-		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-residency-ns in DT\n");
-		rc = -1;
-		goto out;
-	}
+	int i;
 
 	/*
 	 * Set pnv_first_deep_stop_state, pnv_deepest_stop_psscr_{val,mask},
@@ -679,33 +643,36 @@ static int __init pnv_power9_idle_init(struct device_node *np, u32 *flags,
 	 * the shallowest (OPAL_PM_STOP_INST_FAST) loss-less stop state.
 	 */
 	pnv_first_deep_stop_state = MAX_STOP_STATE;
-	for (i = 0; i < dt_idle_states; i++) {
+	for (i = 0; i < nr_pnv_idle_states; i++) {
 		int err;
-		u64 psscr_rl = psscr_val[i] & PSSCR_RL_MASK;
+		struct pnv_idle_states_t *state = &pnv_idle_states[i];
+		u64 psscr_rl = state->psscr_val & PSSCR_RL_MASK;
 
-		if ((flags[i] & OPAL_PM_LOSE_FULL_CONTEXT) &&
-		     (pnv_first_deep_stop_state > psscr_rl))
+		if ((state->flags & OPAL_PM_LOSE_FULL_CONTEXT) &&
+		    pnv_first_deep_stop_state > psscr_rl)
 			pnv_first_deep_stop_state = psscr_rl;
 
-		err = validate_psscr_val_mask(&psscr_val[i], &psscr_mask[i],
-					      flags[i]);
+		err = validate_psscr_val_mask(&state->psscr_val,
+					      &state->psscr_mask,
+					      state->flags);
 		if (err) {
-			report_invalid_psscr_val(psscr_val[i], err);
+			state->valid = false;
+			report_invalid_psscr_val(state->psscr_val, err);
 			continue;
 		}
 
-		if (max_residency_ns < residency_ns[i]) {
-			max_residency_ns = residency_ns[i];
-			pnv_deepest_stop_psscr_val = psscr_val[i];
-			pnv_deepest_stop_psscr_mask = psscr_mask[i];
-			pnv_deepest_stop_flag = flags[i];
+		if (max_residency_ns < state->residency_ns) {
+			max_residency_ns = state->residency_ns;
+			pnv_deepest_stop_psscr_val = state->psscr_val;
+			pnv_deepest_stop_psscr_mask = state->psscr_mask;
+			pnv_deepest_stop_flag = state->flags;
 			deepest_stop_found = true;
 		}
 
 		if (!default_stop_found &&
-		    (flags[i] & OPAL_PM_STOP_INST_FAST)) {
-			pnv_default_stop_val = psscr_val[i];
-			pnv_default_stop_mask = psscr_mask[i];
+		    (state->flags & OPAL_PM_STOP_INST_FAST)) {
+			pnv_default_stop_val = state->psscr_val;
+			pnv_default_stop_mask = state->psscr_mask;
 			default_stop_found = true;
 		}
 	}
@@ -728,11 +695,8 @@ static int __init pnv_power9_idle_init(struct device_node *np, u32 *flags,
 
 	pr_info("cpuidle-powernv: Requested Level (RL) value of first deep stop = 0x%llx\n",
 		pnv_first_deep_stop_state);
-out:
-	kfree(psscr_val);
-	kfree(psscr_mask);
-	kfree(residency_ns);
-	return rc;
+
+	return 0;
 }
 
 /*
@@ -740,50 +704,146 @@ static int __init pnv_power9_idle_init(struct device_node *np, u32 *flags,
  */
 static void __init pnv_probe_idle_states(void)
 {
-	struct device_node *np;
-	int dt_idle_states;
-	u32 *flags = NULL;
 	int i;
 
+	if (nr_pnv_idle_states < 0) {
+		pr_warn("cpuidle-powernv: no idle states found in the DT\n");
+		return;
+	}
+
+	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
+		if (pnv_power9_idle_init())
+			return;
+	}
+
+	for (i = 0; i < nr_pnv_idle_states; i++)
+		supported_cpuidle_states |= pnv_idle_states[i].flags;
+}
+
+/*
+ * This function parses device-tree and populates all the information
+ * into pnv_idle_states structure. It also sets up nr_pnv_idle_states
+ * which is the number of cpuidle states discovered through device-tree.
+ */
+
+static int pnv_parse_cpuidle_dt(void)
+{
+	struct device_node *np;
+	int nr_idle_states, i;
+	int rc = 0;
+	u32 *temp_u32;
+	u64 *temp_u64;
+	const char **temp_string;
+
 	np = of_find_node_by_path("/ibm,opal/power-mgt");
 	if (!np) {
 		pr_warn("opal: PowerMgmt Node not found\n");
-		goto out;
+		return -ENODEV;
 	}
-	dt_idle_states = of_property_count_u32_elems(np,
-			"ibm,cpu-idle-state-flags");
-	if (dt_idle_states < 0) {
-		pr_warn("cpuidle-powernv: no idle states found in the DT\n");
+	nr_idle_states = of_property_count_u32_elems(np,
+						"ibm,cpu-idle-state-flags");
+
+	pnv_idle_states = kcalloc(nr_idle_states, sizeof(*pnv_idle_states),
+				  GFP_KERNEL);
+	temp_u32 = kcalloc(nr_idle_states, sizeof(u32),  GFP_KERNEL);
+	temp_u64 = kcalloc(nr_idle_states, sizeof(u64),  GFP_KERNEL);
+	temp_string = kcalloc(nr_idle_states, sizeof(char *),  GFP_KERNEL);
+
+	if (!(pnv_idle_states && temp_u32 && temp_u64 && temp_string)) {
+		pr_err("Could not allocate memory for dt parsing\n");
+		rc = -ENOMEM;
 		goto out;
 	}
 
-	flags = kcalloc(dt_idle_states, sizeof(*flags),  GFP_KERNEL);
-
-	if (of_property_read_u32_array(np,
-			"ibm,cpu-idle-state-flags", flags, dt_idle_states)) {
+	/* Read flags */
+	if (of_property_read_u32_array(np, "ibm,cpu-idle-state-flags",
+				       temp_u32, nr_idle_states)) {
 		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-flags in DT\n");
+		rc = -EINVAL;
 		goto out;
 	}
+	for (i = 0; i < nr_idle_states; i++)
+		pnv_idle_states[i].flags = temp_u32[i];
+
+	/* Read latencies */
+	if (of_property_read_u32_array(np, "ibm,cpu-idle-state-latencies-ns",
+				       temp_u32, nr_idle_states)) {
+		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n");
+		rc = -EINVAL;
+		goto out;
+	}
+	for (i = 0; i < nr_idle_states; i++)
+		pnv_idle_states[i].latency_ns = temp_u32[i];
+
+	/* Read residencies */
+	if (of_property_read_u32_array(np, "ibm,cpu-idle-state-residency-ns",
+				       temp_u32, nr_idle_states)) {
+		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n");
+		rc = -EINVAL;
+		goto out;
+	}
+	for (i = 0; i < nr_idle_states; i++)
+		pnv_idle_states[i].residency_ns = temp_u32[i];
 
+	/* For power9 */
 	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
-		if (pnv_power9_idle_init(np, flags, dt_idle_states))
+		/* Read pm_crtl_val */
+		if (of_property_read_u64_array(np, "ibm,cpu-idle-state-psscr",
+					       temp_u64, nr_idle_states)) {
+			pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr in DT\n");
+			rc = -EINVAL;
+			goto out;
+		}
+		for (i = 0; i < nr_idle_states; i++)
+			pnv_idle_states[i].psscr_val = temp_u64[i];
+
+		/* Read pm_crtl_mask */
+		if (of_property_read_u64_array(np, "ibm,cpu-idle-state-psscr-mask",
+					       temp_u64, nr_idle_states)) {
+			pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr-mask in DT\n");
+			rc = -EINVAL;
 			goto out;
+		}
+		for (i = 0; i < nr_idle_states; i++)
+			pnv_idle_states[i].psscr_mask = temp_u64[i];
 	}
 
-	for (i = 0; i < dt_idle_states; i++)
-		supported_cpuidle_states |= flags[i];
+	/*
+	 * power8 specific properties ibm,cpu-idle-state-pmicr-mask and
+	 * ibm,cpu-idle-state-pmicr-val were never used and there is no
+	 * plan to use it in near future. Hence, not parsing these properties
+	 */
 
+	if (of_property_read_string_array(np, "ibm,cpu-idle-state-names",
+					  temp_string, nr_idle_states) < 0) {
+		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-names in DT\n");
+		rc = -EINVAL;
+		goto out;
+	}
+	for (i = 0; i < nr_idle_states; i++)
+		strncpy(pnv_idle_states[i].name, temp_string[i],
+			PNV_IDLE_NAME_LEN);
+	nr_pnv_idle_states = nr_idle_states;
+	rc = 0;
 out:
-	kfree(flags);
+	kfree(temp_u32);
+	kfree(temp_u64);
+	kfree(temp_string);
+	return rc;
 }
+
 static int __init pnv_init_idle_states(void)
 {
-
+	int rc = 0;
 	supported_cpuidle_states = 0;
 
+	/* In case we error out nr_pnv_idle_states will be zero */
+	nr_pnv_idle_states = 0;
 	if (cpuidle_disable != IDLE_NO_OVERRIDE)
 		goto out;
-
+	rc = pnv_parse_cpuidle_dt();
+	if (rc)
+		return rc;
 	pnv_probe_idle_states();
 
 	if (!(supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1)) {
-- 
2.18.0.rc2.85.g1fb9df7

Re: [v4, 1/2] powernv/cpuidle: Parse dt idle properties into global structure

[Michael Ellerman]

On Thu, 2018-07-05 at 11:40:21 UTC, Akshay Adiga wrote:
> Device-tree parsing happens twice, once while deciding idle state to be
> used for hotplug and once during cpuidle init. Hence, parsing the device
> tree and caching it will reduce code duplication. Parsing code has been
> moved to pnv_parse_cpuidle_dt() from pnv_probe_idle_states(). In addition
> to the properties in the device tree the number of available states is
> also required.
> 
> Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
> Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
> Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>

Series applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/9c7b185ab2fe313b4426bf55da3624

cheers

[PATCH v4 2/2] powernv/cpuidle: Use parsed device tree values for cpuidle_init

[Akshay Adiga]

Export pnv_idle_states and nr_pnv_idle_states so that its accessible to
cpuidle driver. Use properties from pnv_idle_states structure for powernv
cpuidle_init.

Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/cpuidle.h |   2 +
 drivers/cpuidle/cpuidle-powernv.c  | 158 +++++------------------------
 2 files changed, 28 insertions(+), 132 deletions(-)

diff --git a/arch/powerpc/include/asm/cpuidle.h b/arch/powerpc/include/asm/cpuidle.h
index 574b0ce1d671..43e5f31fe64d 100644
--- a/arch/powerpc/include/asm/cpuidle.h
+++ b/arch/powerpc/include/asm/cpuidle.h
@@ -90,6 +90,8 @@ struct pnv_idle_states_t {
 	bool valid;
 };
 
+extern struct pnv_idle_states_t *pnv_idle_states;
+extern int nr_pnv_idle_states;
 extern u32 pnv_fastsleep_workaround_at_entry[];
 extern u32 pnv_fastsleep_workaround_at_exit[];
 
diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c
index d29e4f041efe..84b1ebe212b3 100644
--- a/drivers/cpuidle/cpuidle-powernv.c
+++ b/drivers/cpuidle/cpuidle-powernv.c
@@ -242,6 +242,7 @@ static inline void add_powernv_state(int index, const char *name,
 	powernv_states[index].target_residency = target_residency;
 	powernv_states[index].exit_latency = exit_latency;
 	powernv_states[index].enter = idle_fn;
+	/* For power8 and below psscr_* will be 0 */
 	stop_psscr_table[index].val = psscr_val;
 	stop_psscr_table[index].mask = psscr_mask;
 }
@@ -263,186 +264,80 @@ static inline int validate_dt_prop_sizes(const char *prop1, int prop1_len,
 extern u32 pnv_get_supported_cpuidle_states(void);
 static int powernv_add_idle_states(void)
 {
-	struct device_node *power_mgt;
 	int nr_idle_states = 1; /* Snooze */
-	int dt_idle_states, count;
-	u32 latency_ns[CPUIDLE_STATE_MAX];
-	u32 residency_ns[CPUIDLE_STATE_MAX];
-	u32 flags[CPUIDLE_STATE_MAX];
-	u64 psscr_val[CPUIDLE_STATE_MAX];
-	u64 psscr_mask[CPUIDLE_STATE_MAX];
-	const char *names[CPUIDLE_STATE_MAX];
+	int dt_idle_states;
 	u32 has_stop_states = 0;
-	int i, rc;
+	int i;
 	u32 supported_flags = pnv_get_supported_cpuidle_states();
 
 
 	/* Currently we have snooze statically defined */
-
-	power_mgt = of_find_node_by_path("/ibm,opal/power-mgt");
-	if (!power_mgt) {
-		pr_warn("opal: PowerMgmt Node not found\n");
-		goto out;
-	}
-
-	/* Read values of any property to determine the num of idle states */
-	dt_idle_states = of_property_count_u32_elems(power_mgt, "ibm,cpu-idle-state-flags");
-	if (dt_idle_states < 0) {
-		pr_warn("cpuidle-powernv: no idle states found in the DT\n");
+	if (nr_pnv_idle_states <= 0) {
+		pr_warn("cpuidle-powernv : Only Snooze is available\n");
 		goto out;
 	}
 
-	count = of_property_count_u32_elems(power_mgt,
-					    "ibm,cpu-idle-state-latencies-ns");
-
-	if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags", dt_idle_states,
-				   "ibm,cpu-idle-state-latencies-ns",
-				   count) != 0)
-		goto out;
-
-	count = of_property_count_strings(power_mgt,
-					  "ibm,cpu-idle-state-names");
-	if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags", dt_idle_states,
-				   "ibm,cpu-idle-state-names",
-				   count) != 0)
-		goto out;
+	/* TODO: Count only states which are eligible for cpuidle */
+	dt_idle_states = nr_pnv_idle_states;
 
 	/*
 	 * Since snooze is used as first idle state, max idle states allowed is
 	 * CPUIDLE_STATE_MAX -1
 	 */
-	if (dt_idle_states > CPUIDLE_STATE_MAX - 1) {
+	if (nr_pnv_idle_states > CPUIDLE_STATE_MAX - 1) {
 		pr_warn("cpuidle-powernv: discovered idle states more than allowed");
 		dt_idle_states = CPUIDLE_STATE_MAX - 1;
 	}
 
-	if (of_property_read_u32_array(power_mgt,
-			"ibm,cpu-idle-state-flags", flags, dt_idle_states)) {
-		pr_warn("cpuidle-powernv : missing ibm,cpu-idle-state-flags in DT\n");
-		goto out;
-	}
-
-	if (of_property_read_u32_array(power_mgt,
-		"ibm,cpu-idle-state-latencies-ns", latency_ns,
-		dt_idle_states)) {
-		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n");
-		goto out;
-	}
-	if (of_property_read_string_array(power_mgt,
-		"ibm,cpu-idle-state-names", names, dt_idle_states) < 0) {
-		pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-names in DT\n");
-		goto out;
-	}
-
 	/*
 	 * If the idle states use stop instruction, probe for psscr values
 	 * and psscr mask which are necessary to specify required stop level.
 	 */
-	has_stop_states = (flags[0] &
+	has_stop_states = (pnv_idle_states[0].flags &
 			   (OPAL_PM_STOP_INST_FAST | OPAL_PM_STOP_INST_DEEP));
-	if (has_stop_states) {
-		count = of_property_count_u64_elems(power_mgt,
-						    "ibm,cpu-idle-state-psscr");
-		if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags",
-					   dt_idle_states,
-					   "ibm,cpu-idle-state-psscr",
-					   count) != 0)
-			goto out;
-
-		count = of_property_count_u64_elems(power_mgt,
-						    "ibm,cpu-idle-state-psscr-mask");
-		if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags",
-					   dt_idle_states,
-					   "ibm,cpu-idle-state-psscr-mask",
-					   count) != 0)
-			goto out;
-
-		if (of_property_read_u64_array(power_mgt,
-		    "ibm,cpu-idle-state-psscr", psscr_val, dt_idle_states)) {
-			pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr in DT\n");
-			goto out;
-		}
-
-		if (of_property_read_u64_array(power_mgt,
-					       "ibm,cpu-idle-state-psscr-mask",
-						psscr_mask, dt_idle_states)) {
-			pr_warn("cpuidle-powernv:Missing ibm,cpu-idle-state-psscr-mask in DT\n");
-			goto out;
-		}
-	}
-
-	count = of_property_count_u32_elems(power_mgt,
-					    "ibm,cpu-idle-state-residency-ns");
-
-	if (count < 0) {
-		rc = count;
-	} else if (validate_dt_prop_sizes("ibm,cpu-idle-state-flags",
-					  dt_idle_states,
-					  "ibm,cpu-idle-state-residency-ns",
-					  count) != 0) {
-		goto out;
-	} else {
-		rc = of_property_read_u32_array(power_mgt,
-						"ibm,cpu-idle-state-residency-ns",
-						residency_ns, dt_idle_states);
-	}
 
 	for (i = 0; i < dt_idle_states; i++) {
 		unsigned int exit_latency, target_residency;
 		bool stops_timebase = false;
+		struct pnv_idle_states_t *state = &pnv_idle_states[i];
 
 		/*
 		 * Skip the platform idle state whose flag isn't in
 		 * the supported_cpuidle_states flag mask.
 		 */
-		if ((flags[i] & supported_flags) != flags[i])
+		if ((state->flags & supported_flags) != state->flags)
 			continue;
 		/*
 		 * If an idle state has exit latency beyond
 		 * POWERNV_THRESHOLD_LATENCY_NS then don't use it
 		 * in cpu-idle.
 		 */
-		if (latency_ns[i] > POWERNV_THRESHOLD_LATENCY_NS)
+		if (state->latency_ns > POWERNV_THRESHOLD_LATENCY_NS)
 			continue;
 		/*
 		 * Firmware passes residency and latency values in ns.
 		 * cpuidle expects it in us.
 		 */
-		exit_latency = DIV_ROUND_UP(latency_ns[i], 1000);
-		if (!rc)
-			target_residency = DIV_ROUND_UP(residency_ns[i], 1000);
-		else
-			target_residency = 0;
-
-		if (has_stop_states) {
-			int err = validate_psscr_val_mask(&psscr_val[i],
-							  &psscr_mask[i],
-							  flags[i]);
-			if (err) {
-				report_invalid_psscr_val(psscr_val[i], err);
+		exit_latency = DIV_ROUND_UP(state->latency_ns, 1000);
+		target_residency = DIV_ROUND_UP(state->residency_ns, 1000);
+
+		if (has_stop_states && !(state->valid))
 				continue;
-			}
-		}
 
-		if (flags[i] & OPAL_PM_TIMEBASE_STOP)
+		if (state->flags & OPAL_PM_TIMEBASE_STOP)
 			stops_timebase = true;
 
-		/*
-		 * For nap and fastsleep, use default target_residency
-		 * values if f/w does not expose it.
-		 */
-		if (flags[i] & OPAL_PM_NAP_ENABLED) {
-			if (!rc)
-				target_residency = 100;
+		if (state->flags & OPAL_PM_NAP_ENABLED) {
 			/* Add NAP state */
 			add_powernv_state(nr_idle_states, "Nap",
 					  CPUIDLE_FLAG_NONE, nap_loop,
 					  target_residency, exit_latency, 0, 0);
 		} else if (has_stop_states && !stops_timebase) {
-			add_powernv_state(nr_idle_states, names[i],
+			add_powernv_state(nr_idle_states, state->name,
 					  CPUIDLE_FLAG_NONE, stop_loop,
 					  target_residency, exit_latency,
-					  psscr_val[i], psscr_mask[i]);
+					  state->psscr_val,
+					  state->psscr_mask);
 		}
 
 		/*
@@ -450,20 +345,19 @@ static int powernv_add_idle_states(void)
 		 * within this config dependency check.
 		 */
 #ifdef CONFIG_TICK_ONESHOT
-		else if (flags[i] & OPAL_PM_SLEEP_ENABLED ||
-			 flags[i] & OPAL_PM_SLEEP_ENABLED_ER1) {
-			if (!rc)
-				target_residency = 300000;
+		else if (state->flags & OPAL_PM_SLEEP_ENABLED ||
+			 state->flags & OPAL_PM_SLEEP_ENABLED_ER1) {
 			/* Add FASTSLEEP state */
 			add_powernv_state(nr_idle_states, "FastSleep",
 					  CPUIDLE_FLAG_TIMER_STOP,
 					  fastsleep_loop,
 					  target_residency, exit_latency, 0, 0);
 		} else if (has_stop_states && stops_timebase) {
-			add_powernv_state(nr_idle_states, names[i],
+			add_powernv_state(nr_idle_states, state->name,
 					  CPUIDLE_FLAG_TIMER_STOP, stop_loop,
 					  target_residency, exit_latency,
-					  psscr_val[i], psscr_mask[i]);
+					  state->psscr_val,
+					  state->psscr_mask);
 		}
 #endif
 		else
-- 
2.18.0.rc2.85.g1fb9df7