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

[Matthias Weisser]

Using mmap we can simulate RAM at a specific address. This also
eliminated the use of system malloc function.

Signed-off-by: Matthias Weisser <weisserm at arcor.de>
---
 arch/sandbox/cpu/os.c     |    9 +++++++++
 arch/sandbox/lib/board.c  |   19 +++++++++++--------
 include/configs/sandbox.h |    1 +
 include/os.h              |   13 +++++++++++++
 4 files changed, 34 insertions(+), 8 deletions(-)

diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
index 6c175d4..cd2fb05 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 +54,11 @@ void os_exit(int exit_code)
 {
 	exit(exit_code);
 }
+
+void *os_mmap(void *addr, size_t length, int prot, int flags, int fd,
+		off_t offset)
+{
+	return mmap((void *)addr, 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..0912a8b 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							*
  ************************************************************************
@@ -112,7 +116,7 @@ typedef int (init_fnc_t) (void);
 
 void __dram_init_banksize(void)
 {
-	gd->bd->bi_dram[0].start = 0;
+	gd->bd->bi_dram[0].start = (ulong) gd->ram_buf;
 	gd->bd->bi_dram[0].size =  gd->ram_size;
 }
 
@@ -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_mmap((void *)CONFIG_SYS_SDRAM_BASE, CONFIG_SYS_SDRAM_SIZE,
+			0, 0, -1, 0);
 	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/include/configs/sandbox.h b/include/configs/sandbox.h
index 0230256..ce4675d 100644
--- a/include/configs/sandbox.h
+++ b/include/configs/sandbox.h
@@ -60,6 +60,7 @@
 #define CONFIG_PHYS_64BIT
 
 /* Size of our emulated memory */
+#define CONFIG_SYS_SDRAM_BASE		0x20000000
 #define CONFIG_SYS_SDRAM_SIZE		(128 << 20)
 
 #define CONFIG_BAUDRATE			115200
diff --git a/include/os.h b/include/os.h
index 3ea6d2d..ed4cd4f 100644
--- a/include/os.h
+++ b/include/os.h
@@ -71,3 +71,16 @@ int os_close(int fd);
  * @param exit_code	exit code for U-Boot
  */
 void os_exit(int exit_code);
+
+/**
+ * Access to the OS mmap() system call. Currently all
+ *
+ * \param addr		Prefered address of the mapping
+ * \param length	Length in bytes
+ * \param prot		Ignored. Always PROT_READ | PROT_WRITE
+ * \param flags		Ignored. Always MAP_PRIVATE | MAP_ANONYMOUS
+ * \param fd		Ignored. Always -1
+ * \param offset	Ignored. Always 0
+ */
+void *os_mmap(void *addr, size_t length, int prot, int flags, int fd,
+		off_t offset);
-- 
1.7.4.1