Hi Patrick,
On Mon, 8 Apr 2019 at 08:18, Patrick Delaunay patrick.delaunay@st.com wrote:
We can remove the pre reloc property in SPL and TPL device-tree:
pre-reloc
- u-boot,dm-pre-reloc
- u-boot,dm-spl
- u-boot,dm-tpl
As only the needed node are kept by fdtgrep (1st pass).
The associated function (XXX_pre_reloc) are simple for SPL/TPL: return always true.
Signed-off-by: Patrick Delaunay patrick.delaunay@st.com
remove pre reloc properties in SPL and TPL device tree
Patch created after some remarks on previous http://patchwork.ozlabs.org/patch/1035797/
I check the current code and I found a way to reduce the SPL device tree size: remove the un-necessary pre reloc parameters in SPL/TPL DT (as the node check is already managed by fdtgrep)
But I need to change the DM code to avoid the check on presence of this parameters...
On my board stm32mp1-ev1, the SPL device tree is reduced by 790 bytes (11149 to 10419) and the SPL binary u-boot-spl.stm32 by 798 bytes (64745 to 63947); the boot is not broken and I have the expected delta between generated device tree.
But I am not sure that I see all the side impact of the code change in SPL/TPL.
PS: I already see a side effect on this patch, because all node are now bounded in SPL/TPL, it is no more needed to TAG all the device tree path but only the last needed children. But in this case phandle for parent node are not keep.
Changes in v2:
- update documentation to describe how the pre-relocation properties are used.
doc/README.SPL | 16 ++++++++++++++++ doc/README.TPL | 4 ++++ doc/driver-model/README.txt | 4 ++++ drivers/core/ofnode.c | 16 ++++++++-------- drivers/core/util.c | 31 +++++++++++++++---------------- scripts/Makefile.lib | 1 + 6 files changed, 48 insertions(+), 24 deletions(-)
Reviewed-by: Simon Glass sjg@chromium.org
This is a nice change, but please see suggestions below.
Also do you think it would be possible to add a little test for this, something like test_ofplatdata? It could use a sample DT (like test.dts) and check that u-boot-spt.dtb ends up without the properties you are removing
diff --git a/doc/README.SPL b/doc/README.SPL index 7a30fef..6eed83f 100644 --- a/doc/README.SPL +++ b/doc/README.SPL @@ -66,6 +66,22 @@ CONFIG_SPL_SPI_LOAD (drivers/mtd/spi/spi_spl_load.o) CONFIG_SPL_RAM_DEVICE (common/spl/spl.c) CONFIG_SPL_WATCHDOG_SUPPORT (drivers/watchdog/libwatchdog.o)
+Device tree +----------- +The U-Boot device tree is filtered by the fdtgrep tools during the build +process to generate a much smaller device tree used in SPL (spl/u-boot-spl.dtb) +with: +- the mandatory nodes (/alias, /chosen, /config) +- the nodes with one pre-relocation property:
- 'u-boot,dm-pre-reloc' or 'u-boot,dm-spl'
+ftgrep is also used to remove: +- the properties defined in CONFIG_OF_SPL_REMOVE_PROPS +- all the pre-relocation properties
- ('u-boot,dm-pre-reloc', 'u-boot,dm-spl' and 'u-boot,dm-tpl')
+All the nodes remaining in the SPL devicetree are bound +(see driver-model/README.txt).
Debugging
diff --git a/doc/README.TPL b/doc/README.TPL index 980debe..c94129f 100644 --- a/doc/README.TPL +++ b/doc/README.TPL @@ -34,6 +34,10 @@ determine which SPL options to choose based on whether CONFIG_TPL_BUILD is set. Source files can be compiled for TPL with options choosed in the board config file.
+TPL use a small device tree (u-boot-tpl.dtb), containing only the nodes with +the pre-relocation properties: 'u-boot,dm-pre-reloc' and 'u-boot,dm-tpl' +(see README.SPL for details).
For example:
spl/Makefile: diff --git a/doc/driver-model/README.txt b/doc/driver-model/README.txt index 07b120d..532a771 100644 --- a/doc/driver-model/README.txt +++ b/doc/driver-model/README.txt @@ -849,6 +849,10 @@ in the device tree node. For U-Boot proper you can use 'u-boot,dm-pre-proper' which means that it will be processed (and a driver bound) in U-Boot proper prior to relocation, but will not be available in SPL or TPL.
+To reduce the size of SPL and TPL, only the nodes with pre-relocation properties +('u-boot,dm-pre-reloc', 'u-boot,dm-spl' or 'u-boot,dm-tpl') are keept in their +device trees (see README.SPL for details); the remaining nodes are always bound.
Then post relocation we throw that away and re-init driver model again. For drivers which require some sort of continuity between pre- and post-relocation devices, we can provide access to the pre-relocation diff --git a/drivers/core/ofnode.c b/drivers/core/ofnode.c index 0e584c1..5a109dd 100644 --- a/drivers/core/ofnode.c +++ b/drivers/core/ofnode.c @@ -700,18 +700,18 @@ int ofnode_read_simple_size_cells(ofnode node)
bool ofnode_pre_reloc(ofnode node) { +#if defined(CONFIG_SPL_BUILD) || defined(CONFIG_TPL_BUILD)
Can you use if IS_ENABLED(CONFIG_SPL_BUILD) ... instead?
Also below?
/* for SPL and TPL the remaining nodes after the fdtgrep 1st pass* had property dm-pre-reloc or u-boot,dm-spl/tpl.* They are removed in final dtb (fdtgrep 2nd pass)*/return true;+#else if (ofnode_read_bool(node, "u-boot,dm-pre-reloc")) return true; if (ofnode_read_bool(node, "u-boot,dm-pre-proper")) return true;
-#ifdef CONFIG_TPL_BUILD
if (ofnode_read_bool(node, "u-boot,dm-tpl"))return true;-#elif defined(CONFIG_SPL_BUILD)
if (ofnode_read_bool(node, "u-boot,dm-spl"))return true;-#else /* * In regular builds individual spl and tpl handling both * count as handled pre-relocation for later second init. @@ -719,9 +719,9 @@ bool ofnode_pre_reloc(ofnode node) if (ofnode_read_bool(node, "u-boot,dm-spl") || ofnode_read_bool(node, "u-boot,dm-tpl")) return true; -#endif
return false;+#endif }
int ofnode_read_resource(ofnode node, uint index, struct resource *res) diff --git a/drivers/core/util.c b/drivers/core/util.c index 27a6848..451f772 100644 --- a/drivers/core/util.c +++ b/drivers/core/util.c @@ -33,16 +33,15 @@ int list_count_items(struct list_head *head)
bool dm_fdt_pre_reloc(const void *blob, int offset) { +#if defined(CONFIG_SPL_BUILD) || defined(CONFIG_TPL_BUILD)
/* for SPL and TPL the remaining nodes after the fdtgrep 1st pass* had property dm-pre-reloc or u-boot,dm-spl/tpl.* They are removed in final dtb (fdtgrep 2nd pass)*/return true;+#else if (fdt_getprop(blob, offset, "u-boot,dm-pre-reloc", NULL)) return true;
-#ifdef CONFIG_TPL_BUILD
if (fdt_getprop(blob, offset, "u-boot,dm-tpl", NULL))return true;-#elif defined(CONFIG_SPL_BUILD)
if (fdt_getprop(blob, offset, "u-boot,dm-spl", NULL))return true;-#else /* * In regular builds individual spl and tpl handling both * count as handled pre-relocation for later second init. @@ -57,16 +56,16 @@ bool dm_fdt_pre_reloc(const void *blob, int offset)
bool dm_ofnode_pre_reloc(ofnode node) { +#if defined(CONFIG_SPL_BUILD) || defined(CONFIG_TPL_BUILD)
/* for SPL and TPL the remaining nodes after the fdtgrep 1st pass* had property dm-pre-reloc or u-boot,dm-spl/tpl.* They are removed in final dtb (fdtgrep 2nd pass)*/return true;+#else if (ofnode_read_bool(node, "u-boot,dm-pre-reloc")) return true;
-#ifdef CONFIG_TPL_BUILD
if (ofnode_read_bool(node, "u-boot,dm-tpl"))return true;-#elif defined(CONFIG_SPL_BUILD)
if (ofnode_read_bool(node, "u-boot,dm-spl"))return true;-#else /* * In regular builds individual spl and tpl handling both * count as handled pre-relocation for later second init. @@ -74,7 +73,7 @@ bool dm_ofnode_pre_reloc(ofnode node) if (ofnode_read_bool(node, "u-boot,dm-spl") || ofnode_read_bool(node, "u-boot,dm-tpl")) return true; -#endif
return false;+#endif } diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 70de9bb..de67677 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -525,4 +525,5 @@ quiet_cmd_fdtgrep = FDTGREP $@ cmd_fdtgrep = $(objtree)/tools/fdtgrep $(fdtgrep_props) -RT $< \ -n /chosen -n /config -O dtb | \ $(objtree)/tools/fdtgrep -r -O dtb - -o $@ \
-P u-boot,dm-pre-reloc -P u-boot,dm-spl -P u-boot,dm-tpl \ $(addprefix -P ,$(subst $\",,$(CONFIG_OF_SPL_REMOVE_PROPS)))-- 2.7.4
Regards, Simon