Driver model can use a lot of memory, as it is the core of all drivers and devices in U-Boot. Add a command to show how much is in use, along with the sizes of various data structures.
This patch can be used to analyse the impact of various potential changes to driver model for SPL, none of which has been implemented. Most involve shrinking the size of struct udevice, which is a particular problem on 64-bit machines since their pointers are so unnecessarily large in SPL.
To try this out, enable SPL_DM_STATS and then build and run on your board. You should see output for SPL and U-Boot proper, like this:
Struct sizes: udevice 90, driver 78, uclass 30, uc_driver 78 Memory: device 11:990, device names 111, uclass a:1e0
Attached type Count Size Cur Tags Save --------------- ----- ----- ----- ----- ----- plat 3 e0 990 914 7c (124) parent_plat 2 40 990 910 80 (128) uclass_plat 1 10 990 90c 84 (132) priv 6 13d 990 920 70 (112) parent_priv 0 0 990 908 88 (136) uclass_priv 3 38 990 914 7c (124) driver_data 0 0 990 908 88 (136) uclass 0 0 Attached total f 2a5 37c (892) tags 0 0
Total size: e15 (3605)
With tags: a99 (2713) - singly-linked: 901 (2305) - driver index: 88a (2186) - uclass index: 813 (2067) Drop device name (not SRAM): 111 (273)
Simon Glass (9): dm: core: Rename dm_dump_all() dm: core: Sort dm subcommands dm: core: Fix addresses in the dm static command dm: core: Add documentation for the dm command dm: core: Switch the testbus driver to use a new struct dm: core: Support accessing core tags dm: core: Add a way to collect memory usage dm: core: Add a command to show driver model statistics dm: spl: Allow SPL to show memory usage
cmd/dm.c | 69 ++++-- common/spl/spl.c | 9 + doc/usage/cmd/dm.rst | 487 ++++++++++++++++++++++++++++++++++++++++ doc/usage/index.rst | 1 + drivers/core/Kconfig | 21 ++ drivers/core/device.c | 65 ++++++ drivers/core/dump.c | 79 ++++++- drivers/core/root.c | 53 +++++ drivers/core/tag.c | 29 +++ drivers/misc/test_drv.c | 6 +- include/dm/device.h | 25 +++ include/dm/root.h | 45 ++++ include/dm/tag.h | 32 ++- include/dm/test.h | 7 + include/dm/util.h | 11 +- test/dm/core.c | 91 ++++++++ tools/dtoc/test_dtoc.py | 6 +- 17 files changed, 1004 insertions(+), 32 deletions(-) create mode 100644 doc/usage/cmd/dm.rst