[Skiboot] [PATCH 1/2] occ: Add support to read V2 format of OCC-OPAL shared memory region

[Shilpasri G Bhat]

Add support to read OCC-OPAL shared memory region version2 to parse
ultra-turbo pstates and core-to-max-frequency-allowed array and append
it to device tree. Each element of core-to-max-frequency-allowed indicates
the maximum frequency sustained with 'n' online cores.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat at linux.vnet.ibm.com>
---
 hw/occ.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 51 insertions(+), 9 deletions(-)

diff --git a/hw/occ.c b/hw/occ.c
index 79140cc..783add9 100644
--- a/hw/occ.c
+++ b/hw/occ.c
@@ -33,6 +33,7 @@
 #define P8_HOMER_SAPPHIRE_DATA_OFFSET	0x1F8000
 
 #define MAX_PSTATES 256
+#define MAX_CORES   16
 
 #define chip_occ_data(chip) \
 		((struct occ_pstate_table *)(chip->homer_base + \
@@ -55,11 +56,12 @@ struct occ_pstate_table {
 	u8 throttle;
 	s8 pstate_min;
 	s8 pstate_nom;
-	s8 pstate_max;
-	u8 spare1;
-	u8 spare2;
+	s8 pstate_turbo;
+	s8 pstate_ultra_turbo;
+	u8 spare;
 	u64 reserved;
 	struct occ_pstate_entry pstates[MAX_PSTATES];
+	s8 core_max[MAX_CORES];
 };
 
 DEFINE_LOG_ENTRY(OPAL_RC_OCC_LOAD, OPAL_PLATFORM_ERR_EVT, OPAL_OCC,
@@ -137,8 +139,9 @@ static bool add_cpu_pstate_properties(s8 *pstate_nom)
 	struct dt_node *power_mgt;
 	u8 nr_pstates;
 	/* Arrays for device tree */
-	u32 *dt_id, *dt_freq;
-	u8 *dt_vdd, *dt_vcs;
+	u32 *dt_id, *dt_freq, *dt_core_max = NULL;
+	u8 *dt_vdd, *dt_vcs, ultra_turbo_en = 0;
+	s8 pmax;
 	bool rc;
 	int i;
 
@@ -164,10 +167,25 @@ static bool add_cpu_pstate_properties(s8 *pstate_nom)
 		return false;
 	}
 
-	nr_pstates = occ_data->pstate_max - occ_data->pstate_min + 1;
+	if (occ_data->version == 1) {
+		pmax = occ_data->pstate_turbo;
+		goto next;
+	}
+
+	if (occ_data->pstate_ultra_turbo > occ_data->pstate_turbo) {
+		ultra_turbo_en = 1;
+		pmax = occ_data->pstate_ultra_turbo;
+
+	} else {
+		ultra_turbo_en = 0;
+		pmax = occ_data->pstate_turbo;
+
+	}
+
+next:	nr_pstates = pmax - occ_data->pstate_min + 1;
 	prlog(PR_DEBUG, "OCC: Min %d Nom %d Max %d Nr States %d\n", 
 	      occ_data->pstate_min, occ_data->pstate_nom,
-	      occ_data->pstate_max, nr_pstates);
+	      pmax, nr_pstates);
 
 	if (nr_pstates <= 1 || nr_pstates > 128) {
 		prerror("OCC: OCC range is not valid\n");
@@ -208,6 +226,19 @@ static bool add_cpu_pstate_properties(s8 *pstate_nom)
 		goto out_free_vdd;
 	}
 
+	if (!ultra_turbo_en)
+		goto populate;
+
+	dt_core_max = (u32 *) malloc(16 * sizeof(u32));
+	if (!dt_core_max) {
+		printf("OCC: dt_core_max alloc failure\n");
+		goto out_free_vcs;
+	}
+
+	for (i = 0; i < 16; i++)
+		dt_core_max[i] = occ_data->core_max[i];
+
+populate:
 	for( i=0; i < nr_pstates; i++) {
 		dt_id[i] = occ_data->pstates[i].id;
 		dt_freq[i] = occ_data->pstates[i].freq_khz/1000;
@@ -222,12 +253,23 @@ static bool add_cpu_pstate_properties(s8 *pstate_nom)
 	dt_add_property(power_mgt, "ibm,pstate-vcss", dt_vcs, nr_pstates);
 	dt_add_property_cells(power_mgt, "ibm,pstate-min", occ_data->pstate_min);
 	dt_add_property_cells(power_mgt, "ibm,pstate-nominal", occ_data->pstate_nom);
-	dt_add_property_cells(power_mgt, "ibm,pstate-max", occ_data->pstate_max);
-
+	dt_add_property_cells(power_mgt, "ibm,pstate-max", pmax);
+	dt_add_property_cells(power_mgt, "ibm,ultra-turbo-en", ultra_turbo_en);
+
+	if (ultra_turbo_en) {
+		dt_add_property_cells(power_mgt, "ibm,pstate-turbo",
+				      occ_data->pstate_turbo);
+		dt_add_property_cells(power_mgt, "ibm,pstate-ultra-turbo",
+				      occ_data->pstate_ultra_turbo);
+		dt_add_property(power_mgt, "ibm,pstate-core-max", dt_core_max,
+				MAX_CORES * 4);
+		free(dt_core_max);
+	}
 	/* Return pstate to set for each core */
 	*pstate_nom = occ_data->pstate_nom;
 	rc = true;
 
+out_free_vcs:
 	free(dt_vcs);
 out_free_vdd:
 	free(dt_vdd);
-- 
1.9.3