Re: [PATCH 6/6] cmd: Add a command to show the memory map

Hi Simon,

We already have a mem info command, which is pretty useless. Can't we reuse that ?

Thanks /Ilias

On Wed, 9 Oct 2024 at 04:50, Simon Glass sjg@chromium.org wrote:

U-Boot has a fairly rigid memory map which is normally not visible unless debugging is enabled in board_f.c

Add a 'memmap' command which shows it. This command does not cover arch-specific pieces but gives a good overview of where things are.

Signed-off-by: Simon Glass sjg@chromium.org

cmd/Kconfig | 10 ++++ cmd/Makefile | 1 + cmd/memmap.c | 66 +++++++++++++++++++++ doc/usage/cmd/memmap.rst | 123 +++++++++++++++++++++++++++++++++++++++ doc/usage/index.rst | 1 + test/cmd/Makefile | 3 +- test/cmd/memmap.c | 35 +++++++++++ 7 files changed, 238 insertions(+), 1 deletion(-) create mode 100644 cmd/memmap.c create mode 100644 doc/usage/cmd/memmap.rst create mode 100644 test/cmd/memmap.c

diff --git a/cmd/Kconfig b/cmd/Kconfig index dd33266cec7..d4a29217323 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -921,6 +921,16 @@ config CMD_MEM_SEARCH pressing return will show the next 10 matches. Environment variables are set for use with scripting (memmatches, memaddr, mempos).

+config CMD_MEMMAP

•   bool "memmap - Memory map"
  

•   default y if SANDBOX
  

•   help
  

•     memmap command
  

•     This shows the location of areas of memory used by U-Boot. This includes
  

•     the malloc() region, U-Boot's code and data, bloblist and anything else
  

•     that prevents a particular region being used for loading images.
  

config CMD_MX_CYCLIC bool "Enable cyclic md/mw commands" depends on CMD_MEMORY diff --git a/cmd/Makefile b/cmd/Makefile index 91227f1249c..4f05dafaaad 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -109,6 +109,7 @@ obj-y += load.o obj-$(CONFIG_CMD_LOG) += log.o obj-$(CONFIG_CMD_LSBLK) += lsblk.o obj-$(CONFIG_CMD_MD5SUM) += md5sum.o +obj-$(CONFIG_CMD_MEMMAP) += memmap.o obj-$(CONFIG_CMD_MEMORY) += mem.o obj-$(CONFIG_CMD_IO) += io.o obj-$(CONFIG_CMD_MII) += mii.o diff --git a/cmd/memmap.c b/cmd/memmap.c new file mode 100644 index 00000000000..d83c04467e9 --- /dev/null +++ b/cmd/memmap.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • Copyright 2024 Google LLC
• • Written by Simon Glass sjg@chromium.org
• */

+#include <bloblist.h> +#include <bootstage.h> +#include <command.h> +#include <malloc.h> +#include <mapmem.h> +#include <asm/global_data.h>

+DECLARE_GLOBAL_DATA_PTR;

+static void print_region(const char *name, ulong base, ulong size, ulong *uptop) +{

•   ulong end = base + size;
  

•   printf("%-12s %8lx %8lx %8lx", name, base, size, end);
  

•   if (*uptop)
  

•           printf(" %8lx", *uptop - end);
  

•   putc('\n');
  

•   *uptop = base;
  

+}

+static int do_memmap(struct cmd_tbl *cmdtp, int flag, int argc,

•                char *const argv[])
  

+{

•   ulong upto, stk_bot;
  

•   printf("%-12s %8s %8s %8s %8s\n", "Region", "Base", "Size", "End",
  

•          "Gap");
  

•   printf("------------------------------------------------\n");
  

•   upto = 0;
  

•   if (IS_ENABLED(CONFIG_VIDEO))
  

•           print_region("video", gd_video_bottom(),
  

•                        gd_video_size(), &upto);
  

•   if (IS_ENABLED(CONFIG_TRACE))
  

•           print_region("trace", map_to_sysmem(gd_trace_buff()),
  

•                        gd_trace_size(), &upto);
  

•   print_region("code", gd->relocaddr, gd->mon_len, &upto);
  

•   print_region("malloc", mem_malloc_start,
  

•                mem_malloc_end - mem_malloc_start, &upto);
  

•   print_region("board_info", map_to_sysmem(gd->bd),
  

•                sizeof(struct bd_info), &upto);
  

•   print_region("global_data", map_to_sysmem(gd),
  

•                sizeof(struct global_data), &upto);
  

•   print_region("devicetree", map_to_sysmem(gd->fdt_blob),
  

•                fdt_totalsize(gd->fdt_blob), &upto);
  

•   if (IS_ENABLED(CONFIG_BOOTSTAGE))
  

•           print_region("bootstage", map_to_sysmem(gd_bootstage()),
  

•                        bootstage_get_size(false), &upto);
  

•   if (IS_ENABLED(CONFIG_BLOBLIST))
  

•           print_region("bloblist", map_to_sysmem(gd_bloblist()),
  

•                        bloblist_get_total_size(), &upto);
  

•   stk_bot = gd->start_addr_sp - CONFIG_STACK_SIZE;
  

•   print_region("stack", stk_bot, CONFIG_STACK_SIZE, &upto);
  

•   print_region("free", gd->ram_base, stk_bot, &upto);
  

•   return 0;
  

+}

+U_BOOT_CMD(

•   memmap, 1, 1, do_memmap, "Show a map of U-Boot's memory usage", ""
  

+); diff --git a/doc/usage/cmd/memmap.rst b/doc/usage/cmd/memmap.rst new file mode 100644 index 00000000000..2f0888a9691 --- /dev/null +++ b/doc/usage/cmd/memmap.rst @@ -0,0 +1,123 @@ +.. SPDX-License-Identifier: GPL-2.0+:

+.. index::

• single: memmap (command)

+memmap command +==============

+Synopsis +--------

+::

• memmap

+Description +-----------

+The memmap command shows the layout of memory used by U-Boot and the region +which is free for use by images.

+The layout of memory is set up before relocation, within the init sequence in +``board_init_f()``, specifically the various ``reserve_...()`` functions. This +'reservation' of memory starts from the top of RAM and proceeds downwards, +ending with the stack. This results in the maximum possible amount of memory +being left free for image-loading.

+The memmap command writes its outputs in 5 columns:

+Region

• Name of the region

+Base

• Base address of the region, i.e. where it starts in memory

+Size

• Size of the region, which may be a little smaller than the actual size
• reserved, e.g. due to alignment

+End

• End of the region. The last byte of the region is one lower than the address
• shown here

+Gap

• Gap between the end of this region and the base of the one above

+Regions shown are:

+video

• Memory reserved for video framebuffers. This reservation happens in the
• bind() methods of all video drivers which are present before relocation,
• so the size depends on that maximum amount of memory which all such drivers
• want to reserve. This may be significantly greater than the amount actually
• needed, if the display is ultimately set to a smaller resolution or colour
• depth than the maximum supported.

+code

• U-Boot's code and Block-Starting Symbol (BSS) region. Before relocation,
• U-Boot copies its code to a high region and sets up a BSS immediately after
• that. The size of this region is generally therefore ``__bss_end`` -
• ``__image_copy_start``

+malloc

• Contains the malloc() heap. The size of this is set by
• ``CONFIG_SYS_MALLOC_LEN``.

+board_info

• Contains the ``bd_info`` structure, with some information about the current
• board.

+global_data

• Contains the global-data structure, pointed to by ``gd``. This includes
• various pointers, values and flags which control U-Boot.

+devicetree

• Contains the flatted devicetree blob (FDT) being used by U-Boot to configure
• itself and its devices.

+bootstage

• Contains the bootstage records, which keep track of boot time as U-Boot
• executes. The size of this is determined by
• ``CONFIG_BOOTSTAGE_RECORD_COUNT``, with each record taking approximately
• 32 bytes.

+bloblist

• Contains the bloblist, which is a list of tables and other data created by
• U-Boot while executed. The size of this is determined by
• ``CONFIG_BLOBLIST_SIZE``.

+stack

• Contains U-Boot's stack, growing downwards from the top. The nominal size of
• this region is set by ``CONFIG_STACK_SIZE`` but there is no actual limit
• enforced, so the stack can grow behind that. Images should be loaded lower
• in memory to avoid any conflict.

+free

• Free memory, which is available for loading images. The base address of
• this is ``gd->ram_base`` which is generally set by ``CFG_SYS_SDRAM_BASE``.

+Example +-------

+::

• => memmap
• Region Base Size End Gap

• ---

• video f000000 1000000 10000000
• code ec3a000 3c5d28 efffd28 2d8
• malloc 8c38000 6002000 ec3a000 0
• board_info 8c37f90 68 8c37ff8 8
• global_data 8c37d80 208 8c37f88 8
• devicetree 8c33000 4d7d 8c37d7d 3
• bootstage 8c32c20 3c8 8c32fe8 18
• bloblist 8c32000 400 8c32400 820
• stack 7c31ff0 1000000 8c31ff0 10
• free 0 7c31ff0 7c31ff0 0

+Return value +------------

+The return value $? is always 0 (true). diff --git a/doc/usage/index.rst b/doc/usage/index.rst index 70563374899..dd2b5807a4f 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -83,6 +83,7 @@ Shell commands cmd/loads cmd/loadx cmd/loady

• cmd/memmap cmd/mbr cmd/md cmd/mmc

diff --git a/test/cmd/Makefile b/test/cmd/Makefile index 8f2134998ad..3f6ae59f3d4 100644 --- a/test/cmd/Makefile +++ b/test/cmd/Makefile @@ -18,8 +18,9 @@ obj-$(CONFIG_CMD_FDT) += fdt.o obj-$(CONFIG_CONSOLE_TRUETYPE) += font.o obj-$(CONFIG_CMD_HISTORY) += history.o obj-$(CONFIG_CMD_LOADM) += loadm.o -obj-$(CONFIG_CMD_MEM_SEARCH) += mem_search.o +obj-$(CONFIG_CMD_MEMMAP) += memmap.o obj-$(CONFIG_CMD_MEMORY) += mem_copy.o +obj-$(CONFIG_CMD_MEM_SEARCH) += mem_search.o ifdef CONFIG_CMD_PCI obj-$(CONFIG_CMD_PCI_MPS) += pci_mps.o endif diff --git a/test/cmd/memmap.c b/test/cmd/memmap.c new file mode 100644 index 00000000000..f12d7174838 --- /dev/null +++ b/test/cmd/memmap.c @@ -0,0 +1,35 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • Test for 'memmap' command
• • Copyright 2024 Google LLC
• • Written by Simon Glass sjg@chromium.org
• */

+#include <dm/test.h> +#include <test/cmd.h> +#include <test/ut.h>

+/* Test 'memmap' command */ +static int cmd_test_memmap(struct unit_test_state *uts) +{

•   ut_assertok(run_command("memmap", 0));
  

•   ut_assert_nextline("Region           Base     Size      End      Gap");
  

•   ut_assert_nextlinen("-");
  

•   /* For now we don't worry about checking the values */
  

•   ut_assert_nextlinen("video");
  

•   ut_assert_nextlinen("code");
  

•   ut_assert_nextlinen("malloc");
  

•   ut_assert_nextlinen("board_info");
  

•   ut_assert_nextlinen("global_data");
  

•   ut_assert_nextlinen("devicetree");
  

•   ut_assert_nextlinen("bootstage");
  

•   ut_assert_nextlinen("bloblist");
  

•   ut_assert_nextlinen("stack");
  

•   ut_assert_nextlinen("free");
  

•   ut_assert_console_end();
  

•   return 0;
  

+}

+CMD_TEST(cmd_test_memmap, UTF_CONSOLE);

2.43.0