Reduce memory footprint to 3MB.

Change-Id: I309bc63bdb27baa21f65de05e12324b9c4ce3407
Reviewed-on: http://gfw160.austin.ibm.com:8080/gerrit/212
Tested-by: Jenkins Server
Reviewed-by: A. Patrick Williams III <iawillia@us.ibm.com>

5 files changed, 82 insertions, 20 deletions

diff --git a/src/kernel/basesegment.C b/src/kernel/basesegment.C
index 70d91ac72..467f8209c 100644
--- a/src/kernel/basesegment.C
+++ b/src/kernel/basesegment.C
@@ -5,6 +5,7 @@
 #include <kernel/segmentmgr.H>
 #include <kernel/block.H>
 #include <kernel/vmmmgr.H>
+#include <kernel/cpuid.H>
 
 BaseSegment::~BaseSegment()
 {
@@ -21,8 +22,22 @@ void BaseSegment::_init()
     // Assign segment to segment manager.
     SegmentManager::addSegment(this, SegmentManager::BASE_SEGMENT_ID);
 
-    // Create initial static 8MB block.
-    iv_block = new Block(0x0, 0x800000);
+    // Create initial static 3 or 8MB block.
+    uint64_t iv_baseBlockSize = 0;
+    switch (CpuID::getCpuType())
+    {
+        case CpuID::POWER7:
+        case CpuID::POWER7_PLUS:
+        case CpuID::POWER8_VENICE:
+            iv_baseBlockSize = VmmManager::EIGHT_MEG;
+            break;
+
+        case CpuID::POWER8_SALERNO:
+        default:
+            iv_baseBlockSize = VmmManager::THREE_MEG;
+            break;
+    }
+    iv_block = new Block(0x0, iv_baseBlockSize);
     iv_block->setParent(this);
 
     // Set default page permissions on block.
diff --git a/src/kernel/cpuid.C b/src/kernel/cpuid.C
new file mode 100644
index 000000000..a8d884bf2
--- /dev/null
+++ b/src/kernel/cpuid.C
@@ -0,0 +1,44 @@
+/** @file cpuid.C
+ *  Implementation of the cpuid functions.
+ */
+
+#include <kernel/cpuid.H>
+
+namespace CpuID
+{
+    ProcessorCoreType getCpuType()
+    {
+        uint64_t l_pvr = getPVR();
+
+        // Layout of the PVR is (32-bit):
+        //     2 nibbles reserved.
+        //     2 nibbles chip type.
+        //     1 nibble technology.
+        //     1 nibble major DD.
+        //     1 nibble reserved.
+        //     1 nibble minor DD.
+
+        switch(l_pvr & 0xFFFF0000)
+        {
+            case 0x003F0000:
+                return POWER7;
+
+            case 0x004A0000:
+                return POWER7_PLUS;
+
+            case 0x004B0000:
+                return POWER8_VENICE;
+
+            default:
+                return UNKNOWN;
+        }
+    }
+
+    uint8_t getCpuDD()
+    {
+        uint64_t l_pvr = getPVR();
+        return ((l_pvr & 0x0F00) >> 4) | (l_pvr & 0x000F);
+    }
+};
+
+
diff --git a/src/kernel/cpumgr.C b/src/kernel/cpumgr.C
index fc421431e..49dfb0919 100644
--- a/src/kernel/cpumgr.C
+++ b/src/kernel/cpumgr.C
@@ -37,19 +37,19 @@ void CpuManager::init()
 
     // Determine number of threads on this core.
     size_t threads = -1;
-    switch (getCpuType())
+    switch (CpuID::getCpuType())
     {
-        case POWER7:
-        case POWER7_PLUS:
+        case CpuID::POWER7:
+        case CpuID::POWER7_PLUS:
             threads = 4;
             break;
 
-        case POWER8_VENICE:
-        case POWER8_SALERNO:
+        case CpuID::POWER8_VENICE:
+        case CpuID::POWER8_SALERNO:
             threads = 8;
             break;
 
-        case UNKNOWN:
+        case CpuID::UNKNOWN:
         default:
             kassert(false);
             break;
@@ -88,9 +88,9 @@ void CpuManager::startCPU(ssize_t i)
     // Initialize CPU structure.
     if (NULL == cv_cpus[i])
     {
-	printk("Starting CPU %ld...", i);    
+	printk("Starting CPU %ld...", i);
 	cpu_t* cpu = cv_cpus[i] = new cpu_t;
-	
+
 	// Initialize CPU.
 	cpu->cpu = i;
     if (currentCPU)
@@ -103,14 +103,14 @@ void CpuManager::startCPU(ssize_t i)
     }
 	cpu->scheduler = &Singleton<Scheduler>::instance();
         cpu->scheduler_extra = NULL;
-	cpu->kernel_stack = 
+	cpu->kernel_stack =
 	    (void*) (((uint64_t)PageManager::allocatePage(4)) + 16320);
         cpu->xscom_mutex = (mutex_t)MUTEX_INITIALIZER;
-	
+
 	// Create idle task.
 	cpu->idle_task = TaskManager::createIdleTask();
 	cpu->idle_task->cpu = cpu;
-	
+
 	printk("done\n");
     }
 
diff --git a/src/kernel/makefile b/src/kernel/makefile
index f3d58dee0..d02141bb6 100644
--- a/src/kernel/makefile
+++ b/src/kernel/makefile
@@ -3,7 +3,7 @@ ROOTPATH = ../..
 OBJS = start.o kernel.o console.o pagemgr.o heapmgr.o taskmgr.o cpumgr.o
 OBJS += syscall.o scheduler.o spinlock.o exception.o vmmmgr.o timemgr.o 
 OBJS += futexmgr.o ptmgr.o segmentmgr.o devicesegment.o basesegment.o
-OBJS += block.o
+OBJS += block.o cpuid.o
 
 include ${ROOTPATH}/config.mk
 
diff --git a/src/kernel/pagemgr.C b/src/kernel/pagemgr.C
index 9ca2821d6..95719b241 100644
--- a/src/kernel/pagemgr.C
+++ b/src/kernel/pagemgr.C
@@ -28,19 +28,19 @@ PageManager::PageManager() : iv_pagesAvail(0)
     uint64_t addr = (uint64_t) VFS_LAST_ADDRESS;
     if (0 != (addr % PAGESIZE))
 	addr = (addr - (addr % PAGESIZE)) + PAGESIZE;
-    
+
     // Determine number of pages available.
     page_t* page = (page_t*)((void*) addr);
     size_t length = (MEMLEN - addr) / PAGESIZE;
 
     // Update statistics.
     __sync_add_and_fetch(&iv_pagesAvail, length);
-    
+
     // Display.
     printk("Initializing PageManager with %zd pages starting at %lx...",
 	   length,
 	   (uint64_t)page);
-    
+
     // Populate L3 cache lines.
     uint64_t* cache_line = (uint64_t*) addr;
     uint64_t* end_cache_line = (uint64_t*) VmmManager::FULL_MEM_SIZE;
@@ -62,6 +62,9 @@ PageManager::PageManager() : iv_pagesAvail(0)
 	length -= (1 << page_length);
     }
 
+    // @TODO: Venice: Clear 3-8MB region and add to free memory pool.
+    //                Can't do this now due to fake-PNOR driver.
+
     printk("done\n");
 }
 
@@ -69,7 +72,7 @@ void* PageManager::_allocatePage(size_t n)
 {
     size_t which_bucket = 0;
     while (n > (size_t)(1 << which_bucket)) which_bucket++;
-    
+
     int retries = 0;
     page_t* page = (page_t*)NULL;
     while ((page == NULL) && (retries < 3))
@@ -109,11 +112,11 @@ void PageManager::_freePage(void* p, size_t n)
 PageManager::page_t* PageManager::pop_bucket(size_t n)
 {
     if (n >= BUCKETS) return NULL;
-    
+
     page_t* p = first_page[n].pop();
 
     if (NULL == p)
-    { 
+    {
 	// Couldn't allocate from the correct size bucket, so split up an
 	// item from the next sized bucket.
 	p = pop_bucket(n+1);