[U-Boot] [PATCH v5 3/3] fit: Support compat string property in configuration node
Simon Goldschmidt
simon.k.r.goldschmidt at gmail.com
Fri Jul 12 06:10:52 UTC 2019
On Thu, Jul 11, 2019 at 10:53 PM Julius Werner <jwerner at chromium.org> wrote:
>
> This patch adds support for an optional optimization to compatible
> string matching where the compatible string property from the root node
> of the kernel FDT can be copied into the configuration node of the FIT
> image. This is most useful when using compressed FDTs or when using FDT
> overlays, where the traditional extraction of the compatible string from
> the kernel FDT itself is not easily possible.
>
> Signed-off-by: Julius Werner <jwerner at chromium.org>
> ---
> - No changes for v2
> - No changes for v3
> - Changes for v4:
> - Added documentation for compatible string in config node.
> - Added example .its file for compressed FDT with compat string in
> config node.
> - No changes for v5
If there haven't been any changes from v4, why did you drop Simon Glass's
Reviewed-by tag?
Regards,
Simon
>
> common/image-fit.c | 67 ++++++++++++---------
> doc/uImage.FIT/kernel_fdts_compressed.its | 73 +++++++++++++++++++++++
> doc/uImage.FIT/source_file_format.txt | 7 +++
> 3 files changed, 119 insertions(+), 28 deletions(-)
> create mode 100644 doc/uImage.FIT/kernel_fdts_compressed.its
>
> diff --git a/common/image-fit.c b/common/image-fit.c
> index c9ffc441aa..e346fed550 100644
> --- a/common/image-fit.c
> +++ b/common/image-fit.c
> @@ -1522,6 +1522,10 @@ int fit_check_format(const void *fit)
> * compatible list, "foo,bar", matches a compatible string in the root of fdt1.
> * "bim,bam" in fdt2 matches the second string which isn't as good as fdt1.
> *
> + * As an optimization, the compatible property from the FDT's root node can be
> + * copied into the configuration node in the FIT image. This is required to
> + * match configurations with compressed FDTs.
> + *
> * returns:
> * offset to the configuration to use if one was found
> * -1 otherwise
> @@ -1554,55 +1558,62 @@ int fit_conf_find_compat(const void *fit, const void *fdt)
> for (noffset = fdt_next_node(fit, confs_noffset, &ndepth);
> (noffset >= 0) && (ndepth > 0);
> noffset = fdt_next_node(fit, noffset, &ndepth)) {
> - const void *kfdt;
> + const void *fdt;
> const char *kfdt_name;
> - int kfdt_noffset;
> + int kfdt_noffset, compat_noffset;
> const char *cur_fdt_compat;
> int len;
> - size_t size;
> + size_t sz;
> int i;
>
> if (ndepth > 1)
> continue;
>
> - kfdt_name = fdt_getprop(fit, noffset, "fdt", &len);
> - if (!kfdt_name) {
> - debug("No fdt property found.\n");
> - continue;
> - }
> - kfdt_noffset = fdt_subnode_offset(fit, images_noffset,
> - kfdt_name);
> - if (kfdt_noffset < 0) {
> - debug("No image node named \"%s\" found.\n",
> - kfdt_name);
> - continue;
> - }
> + /* If there's a compat property in the config node, use that. */
> + if (fdt_getprop(fit, noffset, "compatible", NULL)) {
> + fdt = fit; /* search in FIT image */
> + compat_noffset = noffset; /* search under config node */
> + } else { /* Otherwise extract it from the kernel FDT. */
> + kfdt_name = fdt_getprop(fit, noffset, "fdt", &len);
> + if (!kfdt_name) {
> + debug("No fdt property found.\n");
> + continue;
> + }
> + kfdt_noffset = fdt_subnode_offset(fit, images_noffset,
> + kfdt_name);
> + if (kfdt_noffset < 0) {
> + debug("No image node named \"%s\" found.\n",
> + kfdt_name);
> + continue;
> + }
>
> - if (!fit_image_check_comp(fit, kfdt_noffset, IH_COMP_NONE)) {
> - debug("Can't extract compat from \"%s\" (compressed)\n",
> - kfdt_name);
> - continue;
> - }
> + if (!fit_image_check_comp(fit, kfdt_noffset,
> + IH_COMP_NONE)) {
> + debug("Can't extract compat from \"%s\" "
> + "(compressed)\n", kfdt_name);
> + continue;
> + }
>
> - /*
> - * Get a pointer to this configuration's fdt.
> - */
> - if (fit_image_get_data(fit, kfdt_noffset, &kfdt, &size)) {
> - debug("Failed to get fdt \"%s\".\n", kfdt_name);
> - continue;
> + /* search in this config's kernel FDT */
> + if (fit_image_get_data(fit, kfdt_noffset, &fdt, &sz)) {
> + debug("Failed to get fdt \"%s\".\n", kfdt_name);
> + continue;
> + }
> +
> + compat_noffset = 0; /* search kFDT under root node */
> }
>
> len = fdt_compat_len;
> cur_fdt_compat = fdt_compat;
> /*
> * Look for a match for each U-Boot compatibility string in
> - * turn in this configuration's fdt.
> + * turn in the compat string property.
> */
> for (i = 0; len > 0 &&
> (!best_match_offset || best_match_pos > i); i++) {
> int cur_len = strlen(cur_fdt_compat) + 1;
>
> - if (!fdt_node_check_compatible(kfdt, 0,
> + if (!fdt_node_check_compatible(fdt, compat_noffset,
> cur_fdt_compat)) {
> best_match_offset = noffset;
> best_match_pos = i;
> diff --git a/doc/uImage.FIT/kernel_fdts_compressed.its b/doc/uImage.FIT/kernel_fdts_compressed.its
> new file mode 100644
> index 0000000000..8f81106efc
> --- /dev/null
> +++ b/doc/uImage.FIT/kernel_fdts_compressed.its
> @@ -0,0 +1,73 @@
> +/*
> + * U-Boot uImage source file with a kernel and multiple compressed FDT blobs.
> + * Since the FDTs are compressed, configurations must provide a compatible
> + * string to match directly.
> + */
> +
> +/dts-v1/;
> +
> +/ {
> + description = "Image with single Linux kernel and compressed FDT blobs";
> + #address-cells = <1>;
> +
> + images {
> + kernel {
> + description = "Vanilla Linux kernel";
> + data = /incbin/("./vmlinux.bin.gz");
> + type = "kernel";
> + arch = "ppc";
> + os = "linux";
> + compression = "gzip";
> + load = <00000000>;
> + entry = <00000000>;
> + hash-1 {
> + algo = "crc32";
> + };
> + hash-2 {
> + algo = "sha1";
> + };
> + };
> + fdt at 1 {
> + description = "Flattened Device Tree blob 1";
> + data = /incbin/("./myboard-var1.dtb");
> + type = "flat_dt";
> + arch = "ppc";
> + compression = "gzip";
> + hash-1 {
> + algo = "crc32";
> + };
> + hash-2 {
> + algo = "sha1";
> + };
> + };
> + fdt at 2 {
> + description = "Flattened Device Tree blob 2";
> + data = /incbin/("./myboard-var2.dtb");
> + type = "flat_dt";
> + arch = "ppc";
> + compression = "lzma";
> + hash-1 {
> + algo = "crc32";
> + };
> + hash-2 {
> + algo = "sha1";
> + };
> + };
> + };
> +
> + configurations {
> + default = "conf at 1";
> + conf at 1 {
> + description = "Boot Linux kernel with FDT blob 1";
> + kernel = "kernel";
> + fdt = "fdt at 1";
> + compatible = "myvendor,myboard-variant1";
> + };
> + conf at 2 {
> + description = "Boot Linux kernel with FDT blob 2";
> + kernel = "kernel";
> + fdt = "fdt at 2";
> + compatible = "myvendor,myboard-variant2";
> + };
> + };
> +};
> diff --git a/doc/uImage.FIT/source_file_format.txt b/doc/uImage.FIT/source_file_format.txt
> index d701b9bb76..f8e27ed34e 100644
> --- a/doc/uImage.FIT/source_file_format.txt
> +++ b/doc/uImage.FIT/source_file_format.txt
> @@ -240,6 +240,7 @@ o config-1
> |- fdt = "fdt sub-node unit-name" [, "fdt overlay sub-node unit-name", ...]
> |- fpga = "fpga sub-node unit-name"
> |- loadables = "loadables sub-node unit-name"
> + |- compatible = "vendor,board-style device tree compatible string"
>
>
> Mandatory properties:
> @@ -263,6 +264,12 @@ o config-1
> of strings. U-Boot will load each binary at its given start-address and
> may optionaly invoke additional post-processing steps on this binary based
> on its component image node type.
> + - compatible : The root compatible string of the U-Boot device tree that
> + this configuration shall automatically match when CONFIG_FIT_BEST_MATCH is
> + enabled. If this property is not provided, the compatible string will be
> + extracted from the fdt blob instead. This is only possible if the fdt is
> + not compressed, so images with compressed fdts that want to use compatible
> + string matching must always provide this property.
>
> The FDT blob is required to properly boot FDT based kernel, so the minimal
> configuration for 2.6 FDT kernel is (kernel, fdt) pair.
> --
> 2.20.1
>
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