1 files changed, 45 insertions, 0 deletions
diff --git a/src/northbridge/amd/agesa/family12/northbridge.c b/src/northbridge/amd/agesa/family12/northbridge.c
index 6a591c5851..d7458ff8de 100644
--- a/src/northbridge/amd/agesa/family12/northbridge.c
+++ b/src/northbridge/amd/agesa/family12/northbridge.c
@@ -31,6 +31,7 @@
 #include <cbmem.h>
 
 #include <cpu/x86/lapic.h>
+#include <cpu/amd/mtrr.h>
 
 #include "chip.h"
 #include "northbridge.h"
@@ -468,6 +469,50 @@ static void set_resources(device_t dev)
     printk(BIOS_DEBUG, "Fam12h - northbridge.c - set_resources - End.\n");
 }
 
+void setup_uma_memory(void)
+{
+#if CONFIG_GFXUMA
+  msr_t msr, msr2;
+  uint32_t sys_mem;
+
+  /* TOP_MEM: the top of DRAM below 4G */
+  msr = rdmsr(TOP_MEM);
+  printk
+      (BIOS_INFO, "%s, TOP MEM: msr.lo = 0x%08x, msr.hi = 0x%08x\n",
+       __func__, msr.lo, msr.hi);
+
+  /* TOP_MEM2: the top of DRAM above 4G */
+  msr2 = rdmsr(TOP_MEM2);
+  printk
+      (BIOS_INFO, "%s, TOP MEM2: msr2.lo = 0x%08x, msr2.hi = 0x%08x\n",
+       __func__, msr2.lo, msr2.hi);
+
+  /* refer to UMA Size Consideration in Family12h BKDG. */
+  /* Please reference MemNGetUmaSizeLN () */
+  /*
+   *     Total system memory   UMASize
+   *     >= 2G                 512M
+   *     >=1G                  256M
+   *     <1G                    64M
+   */
+  sys_mem = msr.lo + 0x1000000; // Ignore 16MB allocated for C6 when finding UMA size
+  if ((msr.hi & 0x0000000F) || (sys_mem >= 0x80000000)) {
+    uma_memory_size = 0x20000000;	/* >= 2G memory, 512M recommended UMA */
+  } else if (sys_mem >= 0x40000000) {
+    uma_memory_size = 0x10000000;	/* >= 1G memory, 256M recommended UMA */
+  } else {
+    uma_memory_size = 0x4000000; 	/* <1G memory, 64M recommended UMA */
+  }
+  uma_memory_base = msr.lo - uma_memory_size; /* TOP_MEM1 */
+  printk(BIOS_INFO, "%s: uma size 0x%08llx, memory start 0x%08llx\n",
+        __func__, uma_memory_size, uma_memory_base);
+
+  /* TODO: TOP_MEM2 */
+#else
+  uma_memory_size = 0x10000000; /* 256M recommended UMA */
+  uma_memory_base = 0x30000000; /* 1GB  system memory supported */
+#endif
+}
 
 /* Domain/Root Complex related code */