[PATCH 6/6] cmd: Add a command to show the memory map
Ilias Apalodimas
ilias.apalodimas at linaro.org
Wed Oct 9 12:41:06 CEST 2024
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 at 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 at 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 at 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 at 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
>
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