AMD Fam15tn: Add support for AGESA runtime allocation in CBMEM

The IOMMU AGESA needs a reserved scratch space and it wants
to allocate the stuff for runtime. So provide a simple
allocator for 4 KB CBMEM page.

Change-Id: I53bdfcd2cd69f84fbfbc6edea53a051f516c05cc
Signed-off-by: Rudolf Marek <r.marek@assembler.cz>
Reviewed-on: http://review.coreboot.org/3315
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/include/cbmem.h

@@ -71,6 +71,7 @@
 #define CBMEM_ID_VBOOT_HANDOFF	0x780074f0
 #define CBMEM_ID_CAR_GLOBALS	0xcac4e6a3
 #define CBMEM_ID_NONE		0x00000000
+#define CBMEM_ID_AGESA_RUNTIME	0x41474553
 
 #ifndef __ASSEMBLER__
 #include <stdint.h>

src/lib/cbmem_info.c

@@ -47,6 +47,7 @@ static struct cbmem_id_to_name {
 	{ CBMEM_ID_ROOT,		"CBMEM ROOT " },
 	{ CBMEM_ID_VBOOT_HANDOFF,	"VBOOT      " },
 	{ CBMEM_ID_CAR_GLOBALS,		"CAR GLOBALS" },
+	{ CBMEM_ID_AGESA_RUNTIME,	"AGESA RSVD " },
 };
 
 void cbmem_print_entry(int n, u32 id, u64 base, u64 size)

src/northbridge/amd/agesa/family15tn/fam15tn_callouts.c

@@ -26,6 +26,29 @@
 #include "cbfs.h"
 #include "dimmSpd.h"
 #include "fam15tn_callouts.h"
+#include <cbmem.h>
+
+#define AGESA_RUNTIME_SIZE 4096
+
+static AGESA_STATUS alloc_cbmem(AGESA_BUFFER_PARAMS *AllocParams) {
+	static unsigned int used = 0;
+	void *p = cbmem_find(CBMEM_ID_AGESA_RUNTIME);
+
+	if ((AGESA_RUNTIME_SIZE - used) < AllocParams->BufferLength) {
+		return AGESA_BOUNDS_CHK;
+	}
+
+	/* first time allocation */
+	if (!p) {
+		p = cbmem_add(CBMEM_ID_AGESA_RUNTIME, AGESA_RUNTIME_SIZE);
+		if (!p)
+			return AGESA_BOUNDS_CHK;
+	}
+
+	AllocParams->BufferPointer = p + used;
+	used += AllocParams->BufferLength;
+	return AGESA_SUCCESS;
+}
 
 AGESA_STATUS fam15tn_AllocateBuffer (UINT32 Func, UINT32 Data, VOID *ConfigPtr)
 {
@@ -48,6 +71,10 @@ AGESA_STATUS fam15tn_AllocateBuffer (UINT32 Func, UINT32 Data, VOID *ConfigPtr)
 	AllocParams = ((AGESA_BUFFER_PARAMS *) ConfigPtr);
 	AllocParams->BufferPointer = NULL;
 
+	/* if the allocation is for runtime use simple CBMEM data */
+	if (Data == HEAP_CALLOUT_RUNTIME)
+		return alloc_cbmem(AllocParams);
+
 	AvailableHeapSize = BIOS_HEAP_SIZE - sizeof (BIOS_HEAP_MANAGER);
 	BiosHeapBaseAddr = (UINT8 *) GetHeapBase(&(AllocParams->StdHeader));
 	BiosHeapBasePtr = (BIOS_HEAP_MANAGER *) BiosHeapBaseAddr;