[U-Boot] [PATCH v6 09/10] spl: dm: Make it possible for the SPL to pick its own DTB from a FIT
Jean-Jacques Hiblot
jjhiblot at ti.com
Fri Sep 15 10:57:32 UTC 2017
u-boot can be embedded within a FIT image with multiple DTBs. It then
selects at run-time which one is best suited for the platform.
Use the same principle here for the SPL: put the DTBs in a FIT image,
compress it (LZO, GZIP, or no compression) and append it at the end of the
SPL.
Signed-off-by: Jean-Jacques Hiblot <jjhiblot at ti.com>
---
doc/README.multi-dtb-fit | 56 ++++++++++++++++++++++++++++--
dts/Kconfig | 83 +++++++++++++++++++++++++++++++++++++++++++++
lib/fdtdec.c | 88 +++++++++++++++++++++++++++++++++++++++++++-----
scripts/Makefile.spl | 35 ++++++++++++++++++-
4 files changed, 249 insertions(+), 13 deletions(-)
diff --git a/doc/README.multi-dtb-fit b/doc/README.multi-dtb-fit
index 0d4f068..6cc4965 100644
--- a/doc/README.multi-dtb-fit
+++ b/doc/README.multi-dtb-fit
@@ -1,8 +1,11 @@
-MULTI DTB FIT
+MULTI DTB FIT and SPL_MULTI_DTB_FIT
-The purpose of this feature is to enable u-boot to select its DTB from a FIT
-appended at the end of the binary.
+The purpose of this feature is to enable U-Boot or the SPL to select its DTB
+from a FIT appended at the end of the binary.
+It comes in two flavors: U-Boot (CONFIG_MULTI_DTB_FIT) and SPL
+(CONFIG_SPL_MULTI_DTB_FIT).
+U-Boot flavor:
Usually the DTB is selected by the SPL and passed down to U-Boot. But some
platforms don't use the SPL. In this case MULTI_DTB_FIT can used to provide
U-Boot with a choice of DTBs.
@@ -13,3 +16,50 @@ the FIT.
The selection is done using board_fit_config_name_match() (same as what the SPL
uses to select the DTB for U-Boot). The selection happens during fdtdec_setup()
which is called during before relocation by board_init_f().
+
+SPL flavor:
+the SPL uses only a small subset of the DTB and it usually depends more
+on the SOC than on the board. So it's usually fine to include a DTB in the
+SPL that doesn't exactly match the board. There are howerver some cases
+where it's not possible. In the later case, in order to support multiple
+boards (or board revisions) with the same SPL binary, SPL_MULTI_DTB_FIT
+can be used.
+The relevant DTBs are packed into a FIT. This FIT is automatically generated
+at the end of the compilation, compressed and appended to u-boot-spl.bin, so
+that SPL can locate it and select the correct DTB from inside the FIT.
+CONFIG_SPL__OF_LIST is used to list the relevant DTBs.
+The compression stage is optional but reduces the impact on the size of the
+SPL. LZO and GZIP compressions are supported. By default, the area where the
+FIT is uncompressed is dynamicaly allocated but this behaviour can be changed
+for platforms that don't provide a HEAP big enough to contain the uncompressed
+FIT.
+The SPL uses board_fit_config_name_match() to find the correct DTB within the
+FIT (same as what the SPL uses to select the DTB for U-Boot).
+Uncompression and selection stages happen in fdtdec_setup() which is called
+during the early initialization stage of the SPL (spl_early_init() or
+spl_init())
+
+Impacts and performances (SPL flavor):
+The impact of this option is relatively small. Here are some numbers measured
+for a TI DRA72 platform:
+
+ +----------+------------+-----------+------------+
+ | size | size delta | SPL boot | boot time |
+ | (bytes) | (bytes) | time (s) | delta (s) |
++---------------------------+----------+------------+-----------+------------+
+| 1 DTB | | | | |
++---------------------------+----------+------------+-----------+------------+
+| reference | 125305 | 0 | 1.389 | 0 |
+| LZO (dynamic allocation) | 125391 | 86 | 1.381 | -0.008 |
++---------------------------+----------+------------+-----------+------------+
+| 4 DTBs (DRA7, DRA71, | | | | |
+| DRA72, DRA72 revC) | | | | |
++---------------------------+----------+------------+-----------+------------+
+| LZO (dynamic allocation) | 125991 | 686 | 1.39 | 0.001 |
+| LZO (user defined area) | 125927 | 622 | 1.403 | 0.014 |
+| GZIP (user defined area) | 133880 | 8575 | 1.421 | 0.032 |
+| No compression (in place) | 137472 | 12167 | 1.412 | 0.023 |
++---------------------------+----------+------------+-----------+------------+
+
+Note: SPL boot time is the time elapsed between the 'reset' command is entered
+and the time when the first U-Boot (not SPL) version string is displayed.
diff --git a/dts/Kconfig b/dts/Kconfig
index 28a64d4..d754b57 100644
--- a/dts/Kconfig
+++ b/dts/Kconfig
@@ -126,6 +126,89 @@ config MULTI_DTB_FIT
the correct DTB to be used. Use this if you need to support
multiple DTBs but don't use the SPL.
+
+config SPL_MULTI_DTB_FIT
+ depends on SPL_LOAD_FIT && SPL_OF_CONTROL && !SPL_OF_PLATDATA
+ bool "Support embedding several DTBs in a FIT image for the SPL"
+ help
+ This option provides the SPL with the ability to select its own
+ DTB at runtime from an appended FIT image containing several DTBs.
+ This allows using the same SPL binary on multiple platforms.
+ The primary purpose is to handle different versions of
+ the same platform without tweaking the platform code if the
+ differences can be expressed in the DTBs (common examples are: bus
+ capabilities, pad configurations).
+
+config SPL_OF_LIST
+ string "List of device tree files to include for DT control in SPL"
+ depends on SPL_MULTI_DTB_FIT
+ default OF_LIST
+ help
+ This option specifies a list of device tree files to use for DT
+ control in the SPL. These will be packaged into a FIT. At run-time,
+ the SPL will select the correct DT to use by examining the
+ hardware (e.g. reading a board ID value). This is a list of
+ device tree files (without the directory or .dtb suffix)
+ separated by <space>.
+
+choice
+ prompt "SPL OF LIST compression"
+ depends on SPL_MULTI_DTB_FIT
+ default SPL_MULTI_DTB_FIT_LZO
+
+config SPL_MULTI_DTB_FIT_LZO
+ bool "LZO"
+ depends on SYS_MALLOC_F
+ select SPL_LZO
+ help
+ Compress the FIT image containing the DTBs available for the SPL
+ using LZO compression. (requires lzop on host).
+
+config SPL_MULTI_DTB_FIT_GZIP
+ bool "GZIP"
+ depends on SYS_MALLOC_F
+ select SPL_GZIP
+ help
+ Compress the FIT image containing the DTBs available for the SPL
+ using GZIP compression. (requires gzip on host)
+
+config SPL_MULTI_DTB_FIT_NO_COMPRESSION
+ bool "No compression"
+ help
+ Do not compress the FIT image containing the DTBs available for the SPL.
+ Use this options only if LZO is not available and the DTBs are very small.
+endchoice
+
+choice
+ prompt "Location of uncompressed DTBs "
+ depends on (SPL_MULTI_DTB_FIT_GZIP || SPL_MULTI_DTB_FIT_LZO)
+
+config SPL_MULTI_DTB_FIT_DYN_ALLOC
+ bool "Dynamically allocate the memory"
+ depends on SYS_MALLOC_F
+ default y
+
+config SPL_MULTI_DTB_FIT_USER_DEFINED_AREA
+ bool "User-defined location"
+endchoice
+
+config SPL_MULTI_DTB_FIT_UNCOMPRESS_SZ
+ hex "Size of memory reserved to uncompress the DTBs"
+ depends on (SPL_MULTI_DTB_FIT_GZIP || SPL_MULTI_DTB_FIT_LZO)
+ default 0x8000
+ help
+ This is the size of this area where the DTBs are uncompressed.
+ If this area is dynamically allocated, make sure that
+ SPL_SYS_MALLOC_F_LEN is big enough to contain it.
+
+config SPL_MULTI_DTB_FIT_USER_DEF_ADDR
+ hex "Address of memory where dtbs are uncompressed"
+ depends on SPL_MULTI_DTB_FIT_USER_DEFINED_AREA
+ help
+ the FIT image containing the DTBs is uncompressed in an area defined
+ at compilation time. This is the address of this area. It must be
+ aligned on 2-byte boundary.
+
config OF_SPL_REMOVE_PROPS
string "List of device tree properties to drop for SPL"
depends on SPL_OF_CONTROL
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index f26d2eb..ab916de 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -13,8 +13,10 @@
#include <fdt_support.h>
#include <libfdt.h>
#include <serial.h>
+#include <spl.h>
#include <asm/sections.h>
#include <linux/ctype.h>
+#include <linux/lzo.h>
DECLARE_GLOBAL_DATA_PTR;
@@ -1203,9 +1205,66 @@ int fdtdec_setup_memory_banksize(void)
}
#endif
+#if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
+# if CONFIG_IS_ENABLED(MULTI_DTB_FIT_GZIP) ||\
+ CONFIG_IS_ENABLED(MULTI_DTB_FIT_LZO)
+static int uncompress_blob(const void *src, ulong sz_src, void **dstp)
+{
+ size_t sz_out = CONFIG_SPL_MULTI_DTB_FIT_UNCOMPRESS_SZ;
+ ulong sz_in = sz_src;
+ void *dst;
+ int rc;
+
+ if (CONFIG_IS_ENABLED(GZIP))
+ if (gzip_parse_header(src, sz_in) < 0)
+ return -1;
+ if (CONFIG_IS_ENABLED(LZO))
+ if (!lzop_is_valid_header(src))
+ return -EBADMSG;
+
+ if (CONFIG_IS_ENABLED(MULTI_DTB_FIT_DYN_ALLOC)) {
+ dst = malloc(sz_out);
+ if (!dst) {
+ puts("uncompress_blob: Unable to allocate memory\n");
+ return -ENOMEM;
+ }
+ } else {
+# if CONFIG_IS_ENABLED(MULTI_DTB_FIT_USER_DEFINED_AREA)
+ dst = (void *)CONFIG_VAL(MULTI_DTB_FIT_USER_DEF_ADDR);
+# else
+ return -ENOTSUPP;
+# endif
+ }
+
+ if (CONFIG_IS_ENABLED(GZIP))
+ rc = gunzip(dst, sz_out, (u8 *)src, &sz_in);
+ else if (CONFIG_IS_ENABLED(LZO))
+ rc = lzop_decompress(src, sz_in, dst, &sz_out);
+
+ if (rc < 0) {
+ /* not a valid compressed blob */
+ puts("uncompress_blob: Unable to uncompress\n");
+ if (CONFIG_IS_ENABLED(MULTI_DTB_FIT_DYN_ALLOC))
+ free(dst);
+ return -EBADMSG;
+ }
+ *dstp = dst;
+ return 0;
+}
+# else
+static int uncompress_blob(const void *src, ulong sz_src, void **dstp)
+{
+ return -ENOTSUPP;
+}
+# endif
+#endif
+
int fdtdec_setup(void)
{
#if CONFIG_IS_ENABLED(OF_CONTROL)
+# if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
+ void *fdt_blob;
+# endif
# ifdef CONFIG_OF_EMBED
/* Get a pointer to the FDT */
gd->fdt_blob = __dtb_dt_begin;
@@ -1216,15 +1275,6 @@ int fdtdec_setup(void)
gd->fdt_blob = (ulong *)&_image_binary_end;
else
gd->fdt_blob = (ulong *)&__bss_end;
-
-# elif defined CONFIG_MULTI_DTB_FIT
- gd->fdt_blob = locate_dtb_in_fit(&_end);
-
- if (gd->fdt_blob == NULL || gd->fdt_blob <= ((void *)&_end)) {
- puts("Failed to find proper dtb in embedded FIT Image\n");
- return -1;
- }
-
# else
/* FDT is at end of image */
gd->fdt_blob = (ulong *)&_end;
@@ -1243,7 +1293,27 @@ int fdtdec_setup(void)
gd->fdt_blob = (void *)env_get_ulong("fdtcontroladdr", 16,
(uintptr_t)gd->fdt_blob);
# endif
+
+# if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
+ /*
+ *try and uncompress the blob.
+ * Unfortunately there is no way to know how big the input blob really
+ * is. So let us set the maximum input size arbitrarily high. 16MB
+ * ought to be more than enough for packed DTBs.
+ */
+ if (uncompress_blob(gd->fdt_blob, 0x1000000, &fdt_blob) == 0)
+ gd->fdt_blob = fdt_blob;
+
+ /*
+ * Check if blob is a FIT images containings DTBs.
+ * If so, pick the most relevant
+ */
+ fdt_blob = locate_dtb_in_fit(gd->fdt_blob);
+ if (fdt_blob)
+ gd->fdt_blob = fdt_blob;
+# endif
#endif
+
return fdtdec_prepare_fdt();
}
diff --git a/scripts/Makefile.spl b/scripts/Makefile.spl
index dd8065d..18bd091 100644
--- a/scripts/Makefile.spl
+++ b/scripts/Makefile.spl
@@ -209,10 +209,21 @@ cmd_cat = cat $(filter-out $(PHONY), $^) > $@
quiet_cmd_copy = COPY $@
cmd_copy = cp $< $@
+ifneq ($(CONFIG_SPL_MULTI_DTB_FIT),y)
+FINAL_DTB_CONTAINER = $(obj)/$(SPL_BIN).dtb
+else ifeq ($(CONFIG_SPL_MULTI_DTB_FIT_LZO),y)
+FINAL_DTB_CONTAINER = $(obj)/$(SPL_BIN).multidtb.fit.lzo
+else ifeq ($(CONFIG_SPL_MULTI_DTB_FIT_GZIP),y)
+FINAL_DTB_CONTAINER = $(obj)/$(SPL_BIN).multidtb.fit.gz
+else
+FINAL_DTB_CONTAINER = $(obj)/$(SPL_BIN).multidtb.fit
+endif
+
+
ifeq ($(CONFIG_$(SPL_TPL_)OF_CONTROL)$(CONFIG_OF_SEPARATE)$(CONFIG_$(SPL_TPL_)OF_PLATDATA),yy)
$(obj)/$(SPL_BIN)-dtb.bin: $(obj)/$(SPL_BIN)-nodtb.bin \
$(if $(CONFIG_SPL_SEPARATE_BSS),,$(obj)/$(SPL_BIN)-pad.bin) \
- $(obj)/$(SPL_BIN).dtb FORCE
+ $(FINAL_DTB_CONTAINER) FORCE
$(call if_changed,cat)
$(obj)/$(SPL_BIN).bin: $(obj)/$(SPL_BIN)-dtb.bin FORCE
@@ -382,6 +393,28 @@ checkdtoc: tools
PHONY += FORCE
FORCE:
+PHONY += dtbs
+dtbs:
+ $(Q)$(MAKE) $(build)=dts dtbs
+
# Declare the contents of the .PHONY variable as phony. We keep that
# information in a variable so we can use it in if_changed and friends.
.PHONY: $(PHONY)
+
+SHRUNK_ARCH_DTB = $(patsubst %,$(obj)/dts/%.dtb,$(subst ",,$(CONFIG_SPL_OF_LIST)))
+.SECONDEXPANSION:
+$(SHRUNK_ARCH_DTB): $$(patsubst $(obj)/dts/%, arch/$(ARCH)/dts/%, $$@)
+ $(call if_changed,fdtgrep)
+
+MKIMAGEFLAGS_$(SPL_BIN).multidtb.fit = -f auto -A $(ARCH) -T firmware -C none -O u-boot \
+ -n "Multi DTB fit image for $(SPL_BIN)" -E \
+ $(patsubst %,-b %,$(SHRUNK_ARCH_DTB))
+
+$(obj)/$(SPL_BIN).multidtb.fit: /dev/null $(SHRUNK_ARCH_DTB) FORCE
+ $(call if_changed,mkimage)
+
+$(obj)/$(SPL_BIN).multidtb.fit.gz: $(obj)/$(SPL_BIN).multidtb.fit
+ @gzip -kf9 $< > $@
+
+$(obj)/$(SPL_BIN).multidtb.fit.lzo: $(obj)/$(SPL_BIN).multidtb.fit
+ @lzop -f9 $< > $@
--
1.9.1
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