[U-Boot] [[PATCH V2]] sandbox: Add improved RAM simulation

[Matthias Weisser]

Using mmap to allocate memory from the OS for RAM simulation we can use
u-boots own malloc implementation.

Signed-off-by: Matthias Weisser <weisserm at arcor.de>
---
Changes in V2:
  Removed the address hint for mmap
  Removed the special handling of dlmalloc in common
  Set gd->bd->bi_dram[0].start to 0 again

 arch/sandbox/cpu/os.c    |    7 +++++++
 arch/sandbox/lib/board.c |   17 ++++++++++-------
 common/Makefile          |    2 --
 include/os.h             |    8 ++++++++
 4 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
index 6c175d4..05f91f2 100644
--- a/arch/sandbox/cpu/os.c
+++ b/arch/sandbox/cpu/os.c
@@ -24,6 +24,7 @@
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/mman.h>
 
 #include <os.h>
 
@@ -53,3 +54,9 @@ void os_exit(int exit_code)
 {
 	exit(exit_code);
 }
+
+void *os_malloc(size_t length)
+{
+	return mmap(NULL, length, PROT_READ | PROT_WRITE,
+			MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+}
diff --git a/arch/sandbox/lib/board.c b/arch/sandbox/lib/board.c
index ae5a517..d71cd6f 100644
--- a/arch/sandbox/lib/board.c
+++ b/arch/sandbox/lib/board.c
@@ -45,8 +45,12 @@
 #include <version.h>
 #include <serial.h>
 
+#include <os.h>
+
 DECLARE_GLOBAL_DATA_PTR;
 
+static gd_t gd_mem;
+
 /************************************************************************
  * Init Utilities							*
  ************************************************************************
@@ -147,7 +151,7 @@ void board_init_f(ulong bootflag)
 	uchar *mem;
 	unsigned long addr_sp, addr, size;
 
-	gd = malloc(sizeof(gd_t));
+	gd = &gd_mem;
 	assert(gd);
 
 	memset((void *)gd, 0, sizeof(gd_t));
@@ -158,7 +162,8 @@ void board_init_f(ulong bootflag)
 	}
 
 	size = CONFIG_SYS_SDRAM_SIZE;
-	mem = malloc(size);
+	mem = os_malloc(CONFIG_SYS_SDRAM_SIZE);
+
 	assert(mem);
 	gd->ram_buf = mem;
 	addr = (ulong)(mem + size);
@@ -214,11 +219,9 @@ void board_init_r(gd_t *id, ulong dest_addr)
 	post_output_backlog();
 #endif
 
-#if 0 /* Sandbox uses system malloc for now */
-	/* The Malloc area is immediately below the monitor copy in DRAM */
-	malloc_start = dest_addr - TOTAL_MALLOC_LEN;
-	mem_malloc_init(malloc_start, TOTAL_MALLOC_LEN);
-#endif
+	/* The Malloc area is at the top of simulated DRAM */
+	mem_malloc_init(gd->ram_buf + gd->ram_size - TOTAL_MALLOC_LEN,
+			TOTAL_MALLOC_LEN);
 
 	/* initialize environment */
 	env_relocate();
diff --git a/common/Makefile b/common/Makefile
index 1b672ad..919be42 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -29,9 +29,7 @@ LIB	= $(obj)libcommon.o
 ifndef CONFIG_SPL_BUILD
 COBJS-y += main.o
 COBJS-y += command.o
-ifndef CONFIG_SANDBOX
 COBJS-y += dlmalloc.o
-endif
 COBJS-y += exports.o
 COBJS-$(CONFIG_SYS_HUSH_PARSER) += hush.o
 COBJS-y += image.o
diff --git a/include/os.h b/include/os.h
index 3ea6d2d..2bb2fb7 100644
--- a/include/os.h
+++ b/include/os.h
@@ -71,3 +71,11 @@ int os_close(int fd);
  * @param exit_code	exit code for U-Boot
  */
 void os_exit(int exit_code);
+
+/**
+ * Acquires some memory from the underlying os.
+ *
+ * \param length	Number of bytes to be allocated
+ * \return Pointer to length bytes or NULL on error
+ */
+void *os_malloc(size_t length);
-- 
1.7.4.1