AMD northbridges: rewrite CPU allocation

Use of alloc_find_dev() prevents creation of a device duplicates
for device_path and is SMP safe.

Reduce scope of variables to make the code more readable and in
preparation for refactoring the allocation out of northbridge.c.

Change-Id: I153dc1a5cab4f2eae4ab3a57af02841cb1a261c0
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/1186
Tested-by: build bot (Jenkins)
Reviewed-by: Anton Kochkov <anton.kochkov@gmail.com>
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>

4 files changed, 61 insertions, 86 deletions

diff --git a/src/northbridge/amd/agesa/family10/northbridge.c b/src/northbridge/amd/agesa/family10/northbridge.c
index 4b3859b20a..3a3580a66a 100644
--- a/src/northbridge/amd/agesa/family10/northbridge.c
+++ b/src/northbridge/amd/agesa/family10/northbridge.c
@@ -1311,8 +1311,7 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 	/* Find which cpus are present */
 	cpu_bus = dev->link_list;
 	for (i = 0; i < nodes; i++) {
-		device_t cdb_dev, cpu;
-		struct device_path cpu_path;
+		device_t cdb_dev;
 		unsigned busn, devn;
 		struct bus *pbus;
 
@@ -1355,7 +1354,8 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 
 		cores_found = 0; // one core
 		cdb_dev = dev_find_slot(busn, PCI_DEVFN(devn, 3));
-		if (cdb_dev && cdb_dev->enabled) {
+		int enable_node = cdb_dev && cdb_dev->enabled;
+		if (enable_node) {
 			j = pci_read_config32(cdb_dev, 0xe8);
 			cores_found = (j >> 12) & 3; // dev is func 3
 			if (siblings > 3)
@@ -1374,6 +1374,8 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 			extern CONST OPTIONS_CONFIG_TOPOLOGY ROMDATA TopologyConfiguration;
 			u32 modules = TopologyConfiguration.PlatformNumberOfModules;
 			u32 lapicid_start = 0;
+			struct device_path cpu_path;
+			device_t cpu;
 
 			/* Build the cpu device path */
 			cpu_path.type = DEVICE_PATH_APIC;
@@ -1394,31 +1396,19 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 			}
 			cpu_path.apic.apic_id = (lapicid_start * (i/modules + 1)) + ((i % modules) ? (j + (cores_found + 1)) : j);
 
-			/* See if I can find the cpu */
-			cpu = find_dev_path(cpu_bus, &cpu_path);
-
-			/* Enable the cpu if I have the processor */
-			if (cdb_dev && cdb_dev->enabled) {
-				if (!cpu) {
-					cpu = alloc_dev(cpu_bus, &cpu_path);
-				}
-				if (cpu) {
-					cpu->enabled = 1;
-				}
-			}
-
-			/* Disable the cpu if I don't have the processor */
-			if (cpu && (!cdb_dev || !cdb_dev->enabled)) {
-				cpu->enabled = 0;
-			}
-
-			/* Report what I have done */
-			if (cpu) {
-				cpu->path.apic.node_id = i;
-				cpu->path.apic.core_id = j;
-				printk(BIOS_DEBUG, "CPU: %s %s\n",
-					dev_path(cpu), cpu->enabled?"enabled":"disabled");
-			}
+			/* Update CPU in devicetree. */
+			if (enable_node)
+				cpu = alloc_find_dev(cpu_bus, &cpu_path);
+			else
+				cpu = find_dev_path(cpu_bus, &cpu_path);
+			if (!cpu)
+				continue;
+
+			cpu->enabled = enable_node;
+			cpu->path.apic.node_id = i;
+			cpu->path.apic.core_id = j;
+			printk(BIOS_DEBUG, "CPU: %s %s\n",
+				dev_path(cpu), cpu->enabled?"enabled":"disabled");
 
 		} //j
 	}
diff --git a/src/northbridge/amd/agesa/family14/northbridge.c b/src/northbridge/amd/agesa/family14/northbridge.c
index 875dbbb744..2d0a85f7b4 100644
--- a/src/northbridge/amd/agesa/family14/northbridge.c
+++ b/src/northbridge/amd/agesa/family14/northbridge.c
@@ -832,7 +832,6 @@ static void cpu_bus_set_resources(device_t dev) {
 static u32 cpu_bus_scan(device_t dev, u32 max)
 {
 	device_t cpu;
-	struct device_path cpu_path;
 	int apic_id, cores_found;
 
 	/* There is only one node for fam14, but there may be multiple cores. */
@@ -845,18 +844,18 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 
 
 	for (apic_id = 0; apic_id <= cores_found; apic_id++) {
+		struct device_path cpu_path;
+
 		cpu_path.type = DEVICE_PATH_APIC;
 		cpu_path.apic.apic_id = apic_id;
 		cpu = alloc_find_dev(dev->link_list, &cpu_path);
-		if (cpu) {
-			cpu->enabled = 1;
-			cpu->path.apic.node_id = 0;
-			cpu->path.apic.core_id = apic_id;
-			printk(BIOS_DEBUG, "CPU: %s %s\n",
-					dev_path(cpu), cpu->enabled?"enabled":"disabled");
-		} else {
-			cpu->enabled = 0;
-		}
+		if (!cpu)
+			continue;
+		cpu->enabled = 1;
+		cpu->path.apic.node_id = 0;
+		cpu->path.apic.core_id = apic_id;
+		printk(BIOS_DEBUG, "CPU: %s %s\n",
+			dev_path(cpu), cpu->enabled?"enabled":"disabled");
 	}
 	return max;
 }
diff --git a/src/northbridge/amd/agesa/family15/northbridge.c b/src/northbridge/amd/agesa/family15/northbridge.c
index 96cfca2f8a..02270e7e12 100644
--- a/src/northbridge/amd/agesa/family15/northbridge.c
+++ b/src/northbridge/amd/agesa/family15/northbridge.c
@@ -988,8 +988,7 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 	/* Find which cpus are present */
 	cpu_bus = dev->link_list;
 	for (i = 0; i < node_nums; i++) {
-		device_t cdb_dev, cpu;
-		struct device_path cpu_path;
+		device_t cdb_dev;
 		unsigned busn, devn;
 		struct bus *pbus;
 
@@ -1045,6 +1044,7 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 		} else {
 			siblings = 0; //default one core
 		}
+		int enable_node = cdb_dev && cdb_dev->enabled;
 		printk(BIOS_SPEW, "%s family%xh, core_max=0x%x, core_nums=0x%x, siblings=0x%x\n",
 				dev_path(cdb_dev), 0x0f + family, core_max, core_nums, siblings);
 
@@ -1052,6 +1052,8 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 			extern CONST OPTIONS_CONFIG_TOPOLOGY ROMDATA TopologyConfiguration;
 			u32 modules = TopologyConfiguration.PlatformNumberOfModules;
 			u32 lapicid_start = 0;
+			struct device_path cpu_path;
+			device_t cpu;
 
 			/* Build the cpu device path */
 			cpu_path.type = DEVICE_PATH_APIC;
@@ -1080,28 +1082,19 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 			printk(BIOS_SPEW, "node 0x%x core 0x%x apicid=0x%x\n",
 					i, j, cpu_path.apic.apic_id);
 
-			/* See if I can find the cpu */
-			cpu = find_dev_path(cpu_bus, &cpu_path);
-			/* Enable the cpu if I have the processor */
-			if (cdb_dev && cdb_dev->enabled) {
-				if (!cpu) {
-					cpu = alloc_dev(cpu_bus, &cpu_path);
-				}
-				if (cpu) {
-					cpu->enabled = 1;
-				}
-			}
-			/* Disable the cpu if I don't have the processor */
-			if (cpu && (!cdb_dev || !cdb_dev->enabled)) {
-				cpu->enabled = 0;
-			}
-			/* Report what I have done */
-			if (cpu) {
-				cpu->path.apic.node_id = i;
-				cpu->path.apic.core_id = j;
-				printk(BIOS_DEBUG, "CPU: %s %s\n",
-					dev_path(cpu), cpu->enabled?"enabled":"disabled");
-			}
+			/* Update CPU in devicetree. */
+			if (enable_node)
+				cpu = alloc_find_dev(cpu_bus, &cpu_path);
+			else
+				cpu = find_dev_path(cpu_bus, &cpu_path);
+			if (!cpu)
+				continue;
+
+			cpu->enabled = enable_node;
+			cpu->path.apic.node_id = i;
+			cpu->path.apic.core_id = j;
+			printk(BIOS_DEBUG, "CPU: %s %s\n",
+				dev_path(cpu), cpu->enabled?"enabled":"disabled");
 		} //j
 	}
 	return max;
diff --git a/src/northbridge/amd/agesa/family15tn/northbridge.c b/src/northbridge/amd/agesa/family15tn/northbridge.c
index fb30277884..6fc9434937 100644
--- a/src/northbridge/amd/agesa/family15tn/northbridge.c
+++ b/src/northbridge/amd/agesa/family15tn/northbridge.c
@@ -996,8 +996,7 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 	/* Find which cpus are present */
 	cpu_bus = dev->link_list;
 	for (i = 0; i < node_nums; i++) {
-		device_t cdb_dev, cpu;
-		struct device_path cpu_path;
+		device_t cdb_dev;
 		unsigned busn, devn;
 		struct bus *pbus;
 
@@ -1053,6 +1052,7 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 		} else {
 			siblings = 0; //default one core
 		}
+		int enable_node = cdb_dev && cdb_dev->enabled;
 		printk(BIOS_SPEW, "%s family%xh, core_max=0x%x, core_nums=0x%x, siblings=0x%x\n",
 				dev_path(cdb_dev), 0x0f + family, core_max, core_nums, siblings);
 
@@ -1060,6 +1060,8 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 			extern CONST OPTIONS_CONFIG_TOPOLOGY ROMDATA TopologyConfiguration;
 			u32 modules = TopologyConfiguration.PlatformNumberOfModules;
 			u32 lapicid_start = 0;
+			struct device_path cpu_path;
+			device_t cpu;
 
 			/* Build the cpu device path */
 			cpu_path.type = DEVICE_PATH_APIC;
@@ -1088,28 +1090,19 @@ static u32 cpu_bus_scan(device_t dev, u32 max)
 			printk(BIOS_SPEW, "node 0x%x core 0x%x apicid=0x%x\n",
 					i, j, cpu_path.apic.apic_id);
 
-			/* See if I can find the cpu */
-			cpu = find_dev_path(cpu_bus, &cpu_path);
-			/* Enable the cpu if I have the processor */
-			if (cdb_dev && cdb_dev->enabled) {
-				if (!cpu) {
-					cpu = alloc_dev(cpu_bus, &cpu_path);
-				}
-				if (cpu) {
-					cpu->enabled = 1;
-				}
-			}
-			/* Disable the cpu if I don't have the processor */
-			if (cpu && (!cdb_dev || !cdb_dev->enabled)) {
-				cpu->enabled = 0;
-			}
-			/* Report what I have done */
-			if (cpu) {
-				cpu->path.apic.node_id = i;
-				cpu->path.apic.core_id = j;
-				printk(BIOS_DEBUG, "CPU: %s %s\n",
-					dev_path(cpu), cpu->enabled?"enabled":"disabled");
-			}
+			/* Update CPU in devicetree. */
+			if (enable_node)
+				cpu = alloc_find_dev(cpu_bus, &cpu_path);
+			else
+				cpu = find_dev_path(cpu_bus, &cpu_path);
+			if (!cpu)
+				continue;
+
+			cpu->enabled = enable_node;
+			cpu->path.apic.node_id = i;
+			cpu->path.apic.core_id = j;
+			printk(BIOS_DEBUG, "CPU: %s %s\n",
+				dev_path(cpu), cpu->enabled?"enabled":"disabled");
 		} //j
 	}
 	return max;