i2c: Limit number of CPUs to max supported by firmware.

main.c

@@ -103,13 +103,33 @@ typedef struct
 {
     int8_t index;
     uint8_t *i2c_master;
+    uint8_t vdd_regulator_addr;
+    uint8_t vdn_regulator_addr;
+    uint8_t vdd_smbus_addr;
+    uint8_t vdn_smbus_addr;
 } cpu_info_t;
 static const cpu_info_t g_cpu_info[] = {
-    { .index = 0, .i2c_master = (uint8_t *)I2CMASTER1_BASE },
+    {
+        .index = 0,
+        .i2c_master = (uint8_t *)I2CMASTER1_BASE,
+        .vdd_regulator_addr = 0x70,
+        .vdn_regulator_addr = 0x73,
+        .vdd_smbus_addr = 0x28,
+        .vdn_smbus_addr = 0x2b,
+
+    },
 #ifdef I2CMASTER2_BASE
-    { .index = 1, .i2c_master = (uint8_t *)I2CMASTER2_BASE },
+    {
+        .index = 1,
+        .i2c_master = (uint8_t *)I2CMASTER2_BASE,
+        .vdd_regulator_addr = 0x70,
+        .vdn_regulator_addr = 0x73,
+        .vdd_smbus_addr = 0x28,
+        .vdn_smbus_addr = 0x2b,
+    },
 #endif
 };
+#define MAX_CPUS_SUPPORTED (sizeof(g_cpu_info) / sizeof(g_cpu_info[0]))
 
 void primary_service_event_loop(void);
 
@@ -1379,7 +1399,7 @@ static int apply_avsbus_workarounds_cpu(const cpu_info_t *cpu)
     printf("\tVDD/VCS %d: Enabling AVSBus CLK/MDAT pullups and selecting "
            "VIH/VIL 0x2 (0.65V/0.55V)\n",
            cpu->index);
-    if (i2c_write_register_byte(cpu->i2c_master, 0x28, 0x2e, 0x23))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdd_smbus_addr, 0x2e, 0x23))
     {
         return -1;
     }
@@ -1387,7 +1407,7 @@ static int apply_avsbus_workarounds_cpu(const cpu_info_t *cpu)
     printf("\tVDN %d: Enabling AVSBus CLK/MDAT pullups and selecting VIH/VIL "
            "0x2 (0.65V/0.55V)\n",
            cpu->index);
-    if (i2c_write_register_byte(cpu->i2c_master, 0x2b, 0x2e, 0x23))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdn_smbus_addr, 0x2e, 0x23))
     {
         return -1;
     }
@@ -1415,31 +1435,31 @@ static int apply_avsbus_workarounds(const cpu_info_t *cpu_info, int cpu_count)
 static int enable_avsbus_pmbus_cpu(const cpu_info_t *cpu)
 {
     printf("\tVDD %d: Placing device in AVSBus voltage command mode\n", cpu->index);
-    if (i2c_write_register_byte(cpu->i2c_master, 0x70, 0x00, 0x00))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdd_regulator_addr, 0x00, 0x00))
     {
         return -1;
     }
-    if (i2c_write_register_byte(cpu->i2c_master, 0x70, 0x01, 0xb0))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdd_regulator_addr, 0x01, 0xb0))
     {
         return -1;
     }
 
     printf("\tVCS %d: Placing device in AVSBus voltage command mode\n", cpu->index);
-    if (i2c_write_register_byte(cpu->i2c_master, 0x70, 0x00, 0x01))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdd_regulator_addr, 0x00, 0x01))
     {
         return -1;
     }
-    if (i2c_write_register_byte(cpu->i2c_master, 0x70, 0x01, 0xb0))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdd_regulator_addr, 0x01, 0xb0))
     {
         return -1;
     }
 
     printf("\tVDN %d: Placing device in AVSBus voltage command mode\n", cpu->index);
-    if (i2c_write_register_byte(cpu->i2c_master, 0x73, 0x00, 0x00))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdn_regulator_addr, 0x00, 0x00))
     {
         return -1;
     }
-    if (i2c_write_register_byte(cpu->i2c_master, 0x73, 0x01, 0xb0))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdn_regulator_addr, 0x01, 0xb0))
     {
         return -1;
     }
@@ -1467,31 +1487,31 @@ static int enable_avsbus_pmbus(const cpu_info_t *cpu_info, int cpu_count)
 static int disable_avsbus_pmbus_cpu(const cpu_info_t *cpu)
 {
     printf("\tVDD %d: Placing device in immediate off mode\n", cpu->index);
-    if (i2c_write_register_byte(cpu->i2c_master, 0x70, 0x00, 0x00))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdd_regulator_addr, 0x00, 0x00))
     {
         return -1;
     }
-    if (i2c_write_register_byte(cpu->i2c_master, 0x70, 0x01, 0xb0))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdd_regulator_addr, 0x01, 0xb0))
     {
         return -1;
     }
 
     printf("\tVCS %d: Placing device in immediate off mode\n", cpu->index);
-    if (i2c_write_register_byte(cpu->i2c_master, 0x70, 0x00, 0x01))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdd_regulator_addr, 0x00, 0x01))
     {
         return -1;
     }
-    if (i2c_write_register_byte(cpu->i2c_master, 0x70, 0x01, 0xb0))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdd_regulator_addr, 0x01, 0xb0))
     {
         return -1;
     }
 
     printf("\tVDN %d: Placing device in immediate off mode\n", cpu->index);
-    if (i2c_write_register_byte(cpu->i2c_master, 0x73, 0x00, 0x00))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdn_regulator_addr, 0x00, 0x00))
     {
         return -1;
     }
-    if (i2c_write_register_byte(cpu->i2c_master, 0x73, 0x01, 0xb0))
+    if (i2c_write_register_byte(cpu->i2c_master, cpu->vdn_regulator_addr, 0x01, 0xb0))
     {
         return -1;
     }
@@ -1500,19 +1520,21 @@ static int disable_avsbus_pmbus_cpu(const cpu_info_t *cpu)
 }
 static int disable_avsbus_pmbus(const cpu_info_t *cpu_info, int cpu_count)
 {
+    int status = 0;
     printf("Disabling AVSbus PMBUS functionality...\n");
 
     while (--cpu_count)
     {
+        // Attempt to turn of power on all CPUs, even if one isn't responding.
         if (disable_avsbus_pmbus_cpu(&cpu_info[0]))
         {
-            return -1;
+            status = -1;
         }
         cpu_info++;
     }
 
     printf("\tAVSBus PMBUS functionality disabled!\n");
-    return 0;
+    return status;
 }
 
 static void power_off_chassis(void)
@@ -1584,6 +1606,11 @@ static int power_on_chassis(void)
     }
     printf("Chassis power verified active\n");
     configured_cpu_count = cpu_count;
+    if (cpu_count > MAX_CPUS_SUPPORTED)
+    {
+        configured_cpu_count = cpu_count = MAX_CPUS_SUPPORTED;
+        printf("Limiting number of CPUs to %d\n", MAX_CPUS_SUPPORTED);
+    }
     printf("%d CPU(s) installed\n", cpu_count);
 
     // Apply AVSBus workarounds