Hikey960: Change to use recommended power state id format

ARM Power State Coordination Interface (ARM DEN 0022D) chapter
6.5 "Recommended StateID Encoding" defines the state ID which can be
used by platforms. The recommended power states can be presented by
below values; and it divides into three fields, every field has 4 bits
to present power states corresponding to core level, cluster level and
system level.

  0: Run
  1: Standby
  2: Retention
  3: Powerdown

This commit changes to use upper recommended power states definition on
Hikey960; and changes the power state validate function to check the
power state passed from kernel side.

Signed-off-by: Leo Yan <leo.yan@linaro.org>

2 files changed, 64 insertions, 29 deletions

diff --git a/plat/hisilicon/hikey960/hikey960_pm.c b/plat/hisilicon/hikey960/hikey960_pm.c
index 348cdba5..078f0d81 100644
--- a/plat/hisilicon/hikey960/hikey960_pm.c
+++ b/plat/hisilicon/hikey960/hikey960_pm.c
@@ -26,6 +26,38 @@
 #define SYSTEM_PWR_STATE(state) \
 	((state)->pwr_domain_state[PLAT_MAX_PWR_LVL])
 
+#define PSTATE_WIDTH		4
+#define PSTATE_MASK		((1 << PSTATE_WIDTH) - 1)
+
+#define MAKE_PWRSTATE(lvl2_state, lvl1_state, lvl0_state, pwr_lvl, type) \
+		(((lvl2_state) << (PSTATE_ID_SHIFT + PSTATE_WIDTH * 2)) | \
+		 ((lvl1_state) << (PSTATE_ID_SHIFT + PSTATE_WIDTH)) | \
+		 ((lvl0_state) << (PSTATE_ID_SHIFT)) | \
+		 ((pwr_lvl) << PSTATE_PWR_LVL_SHIFT) | \
+		 ((type) << PSTATE_TYPE_SHIFT))
+
+/*
+ * The table storing the valid idle power states. Ensure that the
+ * array entries are populated in ascending order of state-id to
+ * enable us to use binary search during power state validation.
+ * The table must be terminated by a NULL entry.
+ */
+const unsigned int hikey960_pwr_idle_states[] = {
+	/* State-id - 0x001 */
+	MAKE_PWRSTATE(PLAT_MAX_RUN_STATE, PLAT_MAX_RUN_STATE,
+		      PLAT_MAX_STB_STATE, MPIDR_AFFLVL0, PSTATE_TYPE_STANDBY),
+	/* State-id - 0x002 */
+	MAKE_PWRSTATE(PLAT_MAX_RUN_STATE, PLAT_MAX_RUN_STATE,
+		      PLAT_MAX_RET_STATE, MPIDR_AFFLVL0, PSTATE_TYPE_STANDBY),
+	/* State-id - 0x003 */
+	MAKE_PWRSTATE(PLAT_MAX_RUN_STATE, PLAT_MAX_RUN_STATE,
+		      PLAT_MAX_OFF_STATE, MPIDR_AFFLVL0, PSTATE_TYPE_POWERDOWN),
+	/* State-id - 0x033 */
+	MAKE_PWRSTATE(PLAT_MAX_RUN_STATE, PLAT_MAX_OFF_STATE,
+		      PLAT_MAX_OFF_STATE, MPIDR_AFFLVL1, PSTATE_TYPE_POWERDOWN),
+	0,
+};
+
 #define DMAC_GLB_REG_SEC	0x694
 #define AXI_CONF_BASE		0x820
 
@@ -36,16 +68,21 @@ static void hikey960_pwr_domain_standby(plat_local_state_t cpu_state)
 	unsigned long scr;
 	unsigned int val = 0;
 
-	assert(cpu_state == PLAT_MAX_RET_STATE);
+	assert(cpu_state == PLAT_MAX_STB_STATE ||
+	       cpu_state == PLAT_MAX_RET_STATE);
 
 	scr = read_scr_el3();
 
 	/* Enable Physical IRQ and FIQ to wake the CPU*/
 	write_scr_el3(scr | SCR_IRQ_BIT | SCR_FIQ_BIT);
 
-	set_retention_ticks(val);
+	if (cpu_state == PLAT_MAX_RET_STATE)
+		set_retention_ticks(val);
+
 	wfi();
-	clr_retention_ticks(val);
+
+	if (cpu_state == PLAT_MAX_RET_STATE)
+		clr_retention_ticks(val);
 
 	/*
 	 * Restore SCR to the original value, synchronisazion of
@@ -124,38 +161,34 @@ static void __dead2 hikey960_system_reset(void)
 int hikey960_validate_power_state(unsigned int power_state,
 			       psci_power_state_t *req_state)
 {
-	int pstate = psci_get_pstate_type(power_state);
-	int pwr_lvl = psci_get_pstate_pwrlvl(power_state);
+	unsigned int state_id;
 	int i;
 
 	assert(req_state);
 
-	if (pwr_lvl > PLAT_MAX_PWR_LVL)
-		return PSCI_E_INVALID_PARAMS;
-
-	/* Sanity check the requested state */
-	if (pstate == PSTATE_TYPE_STANDBY) {
-		/*
-		 * It's possible to enter standby only on power level 0
-		 * Ignore any other power level.
-		 */
-		if (pwr_lvl != MPIDR_AFFLVL0)
-			return PSCI_E_INVALID_PARAMS;
-
-		req_state->pwr_domain_state[MPIDR_AFFLVL0] =
-					PLAT_MAX_RET_STATE;
-	} else {
-		for (i = MPIDR_AFFLVL0; i <= pwr_lvl; i++)
-			req_state->pwr_domain_state[i] =
-					PLAT_MAX_OFF_STATE;
-	}
-
 	/*
-	 * We expect the 'state id' to be zero.
+	 *  Currently we are using a linear search for finding the matching
+	 *  entry in the idle power state array. This can be made a binary
+	 *  search if the number of entries justify the additional complexity.
 	 */
-	if (psci_get_pstate_id(power_state))
+	for (i = 0; !!hikey960_pwr_idle_states[i]; i++) {
+		if (power_state == hikey960_pwr_idle_states[i])
+			break;
+	}
+
+	/* Return error if entry not found in the idle state array */
+	if (!hikey960_pwr_idle_states[i])
 		return PSCI_E_INVALID_PARAMS;
 
+	i = 0;
+	state_id = psci_get_pstate_id(power_state);
+
+	/* Parse the State ID and populate the state info parameter */
+	while (state_id) {
+		req_state->pwr_domain_state[i++] = state_id & PSTATE_MASK;
+		state_id >>= PSTATE_WIDTH;
+	}
+
 	return PSCI_E_SUCCESS;
 }
 
diff --git a/plat/hisilicon/hikey960/include/platform_def.h b/plat/hisilicon/hikey960/include/platform_def.h
index cb760907..2ac7f2a7 100644
--- a/plat/hisilicon/hikey960/include/platform_def.h
+++ b/plat/hisilicon/hikey960/include/platform_def.h
@@ -31,8 +31,10 @@
 #define PLAT_NUM_PWR_DOMAINS		(PLATFORM_CORE_COUNT + \
 					 PLATFORM_CLUSTER_COUNT + 1)
 
-#define PLAT_MAX_RET_STATE		1
-#define PLAT_MAX_OFF_STATE		2
+#define PLAT_MAX_RUN_STATE		0
+#define PLAT_MAX_STB_STATE		1
+#define PLAT_MAX_RET_STATE		2
+#define PLAT_MAX_OFF_STATE		3
 
 #define MAX_IO_DEVICES			3
 #define MAX_IO_HANDLES			4