On Sat, 29 Jun 2024 at 10:01, Heinrich Schuchardt
<heinrich.schucha...@canonical.com> wrote:
>
> The dtbdump.efi binary can be used for testing the EFI_DT_FIXUP_PROTOCOL.
> It provides a command to load a file and have it fixed up and a
> command to save the resulting file.
>
> Add a command 'dump' for displaying the device-tree.
>
> Signed-off-by: Heinrich Schuchardt <heinrich.schucha...@canonical.com>
> ---
> v2:
> print leading '/dts-v1/;'
> print memory reservation block
> allow space in string property value to match dtc logic
> correct formatting of byte strings
> ---
> lib/efi_loader/dtbdump.c | 261 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 261 insertions(+)
>
> diff --git a/lib/efi_loader/dtbdump.c b/lib/efi_loader/dtbdump.c
> index 5f39cf22da7..116593d9e25 100644
> --- a/lib/efi_loader/dtbdump.c
> +++ b/lib/efi_loader/dtbdump.c
> @@ -40,6 +40,53 @@ static void print(u16 *string)
> cout->output_string(cout, string);
> }
>
> +/**
> + * print_char() - print character
> + *
> + * 0x00 is replaced by '", "'.
> + *
> + * @c: - character
> + */
> +static void print_char(unsigned char c)
> +{
> + u16 out[2] = u"?";
> +
> + if (!c) {
> + print(u"\", \"");
> + return;
> + }
> +
> + if (c > 0x1f && c < 0x80)
> + out[0] = c;
> +
> + print(out);
> +}
> +
> +/**
> + * print_hex_digit() - print hexadecimal digit
> + *
> + * @digit: digit to print
> + */
> +static void print_hex_digit(unsigned char digit)
> +{
> + if (digit < 10)
> + digit += '0';
> + else
> + digit += 'a' - 10;
> + print_char(digit);
> +}
> +
> +/**
> + * printx() - print hexadecimal byte
> + *
> + * @val: value to print
> + */
> +static void printx(unsigned char val)
> +{
> + print_hex_digit(val >> 4);
> + print_hex_digit(val & 0xf);
> +}
> +
> /**
> * error() - print error string
> *
> @@ -227,6 +274,7 @@ bool starts_with(u16 *string, u16 *keyword)
> */
> void do_help(void)
> {
> + error(u"dump - print device-tree\r\n");
> error(u"load <dtb> - load device-tree from file\r\n");
> error(u"save <dtb> - save device-tree to file\r\n");
> error(u"exit - exit the shell\r\n");
> @@ -489,6 +537,217 @@ efi_status_t do_save(u16 *filename)
> return ret;
> }
>
> +/**
> + * indent() - print a number of tabstops
> + *
> + * @level: indentation level
> + */
> +static void indent(u32 level)
> +{
> + for (; level; --level)
> + print(u"\t");
> +}
> +
> +/**
> + * is_string_value() - determine if property is a string
> + *
> + * If a property is a string, an x-string, or a u32 cannot be deducted
> + * from the device-tree. Therefore a heuristic is used.
> + *
> + * @str: pointer to device-tree property
> + * @len: length of the device-tree property
> + * Return: 1 for string, 0 otherwise
> + */
> +static int is_string_value(const unsigned char *str, u32 len)
> +{
> + int nonzero_flag = 0;
> +
> + /* Zero length or not ending with 0x00 */
> + if (!len || str[len - 1])
> + return 0;
> +
> + for (u32 i = 0; i < len; ++i) {
> + if (!str[i]) {
> + /* Zero length string or two consecutive 0x00 */
> + if (!nonzero_flag)
> + return 0;
> +
> + nonzero_flag = 0;
> +
> + continue;
> + }
> + /* Non-printable */
> + if (str[i] < 0x20 || str[i] >= 0x80)
> + return 0;
> +
> + nonzero_flag = 1;
> + }
> +
> + return 1;
> +}
> +
> +/**
> + * print_property() - print device-tree property
> + *
> + * If a property is a string, an x-string, or a u32 cannot be deducted
> + * from the device-tree. Therefore a heuristic is used.
> + *
> + * @str: property value
> + * @len: length of property value
> + */
> +static void print_property(const unsigned char *val, u32 len)
> +{
> + if (is_string_value(val, len)) {
> + /* string */
> + print(u"\"");
> + for (int i = 0; i < len - 1; ++i)
> + print_char(val[i]);
> + print(u"\"");
> + } else if (len & 0x3) {
> + /* byte string */
> + print(u"[");
> + for (int i = 0; i < len; ++i) {
> + if (i)
> + print(u" ");
> + printx(val[i]);
> + }
> + print(u"]\"");
> + } else {
> + /* cell list */
> + print(u"<");
> + for (u32 i = 0; i < len; ++i) {
> + if ((i & 0x3) == 0) {
> + if (i > 0)
> + print(u" ");
> + print(u"0x");
> + }
> + printx(val[i]);
> + }
> + print(u">");
> + }
> +}
> +
> +/**
> + * print_mem_res_block() - print memory reservation block
> + *
> + * @rsvblk: memory reservation block
> + */
> +static void print_mem_res_block(const struct fdt_reserve_entry *rsvblk)
> +{
> + for (; rsvblk->address || rsvblk->size; ++rsvblk) {
> + const unsigned char *val;
> +
> + print(u"/memreserve/ 0x");
> + val = (const unsigned char *)&rsvblk->address;
> + for (u32 i = 0; i < sizeof(u64); ++i)
> + printx(val[i]);
> + print(u" 0x");
> + val = (const unsigned char *)&rsvblk->size;
> + for (u32 i = 0; i < sizeof(u64); ++i)
> + printx(val[i]);
> + print(u";\r\n");
> + }
> +}
> +
> +/**
> + * do_dump() - print device-tree
> + */
> +static efi_status_t do_dump(void)
> +{
> + const unsigned char *fdt;
> + struct fdt_header *header;
> + const u32 *end;
> + const u32 *pos;
> + const char *strings;
> + u32 level = 0;
> +
> + fdt = get_dtb(systable);
> + if (!fdt) {
> + error(u"DTB not found\r\n");
> + return EFI_NOT_FOUND;
> + }
> +
> + header = (struct fdt_header *)fdt;
> + if (f2h(header->magic) != FDT_MAGIC) {
> + error(u"Wrong device tree magic\r\n");
> + error(u"Not a device-tree\r\n");
> + return EFI_LOAD_ERROR;
> + }
> +
> + pos = (u32 *)(fdt + f2h(header->off_dt_struct));
> + end = &pos[f2h(header->totalsize) >> 2];
> + strings = fdt + f2h(header->off_dt_strings);
> +
> + print(u"/dts-v1/;\r\n");
> +
> + print_mem_res_block((const struct fdt_reserve_entry *)
> + (fdt + f2h(header->off_mem_rsvmap)));
> +
> + print(u"/");
> + for (; pos < end;) {
> + switch (f2h(pos[0])) {
> + case FDT_BEGIN_NODE: {
> + const char *c = (char *)&pos[1];
> + size_t i;
> +
> + indent(level);
> + for (i = 0; c[i]; ++i)
> + print_char(c[i]);
> + print(u" {\n\r");
> +
> + ++level;
> + pos = &pos[2 + (i >> 2)];
> + break;
> + }
> + case FDT_PROP: {
> + struct fdt_property *prop = (struct fdt_property
> *)pos;
> + const unsigned char *label =
> &strings[f2h(prop->nameoff)];
> + u32 len = f2h(prop->len);
> + const unsigned char *str = (unsigned char *)&pos[3];
> +
> + indent(level);
> + for (int i = 0; label[i]; ++i)
> + print_char(label[i]);
> +
> + if (len) {
> + print(u" = ");
> + print_property(str, len);
> + }
> + print(u";\r\n");
> +
> + pos = &pos[3 + ((f2h(prop->len) + 3) >> 2)];
> + break;
> + }
> + case FDT_NOP:
> + ++pos;
> + break;
> + case FDT_END_NODE:
> + if (!level) {
> + error(u"Extraneous end node\r\n");
> + return EFI_LOAD_ERROR;
> + }
> +
> + --level;
> + indent(level);
> + print(u"};\n\r");
> + ++pos;
> + break;
> + case FDT_END:
> + if (level) {
> + error(u"Missing end node\r\n");
> + return EFI_LOAD_ERROR;
> + }
> + return EFI_SUCCESS;
> + default:
> + error(u"Invalid device tree token\r\n");
> + return EFI_LOAD_ERROR;
> + }
> + }
> + error(u"Overrun\r\n");
> +
> + return EFI_LOAD_ERROR;
> +}
> +
> /**
> * efi_main() - entry point of the EFI application.
> *
> @@ -524,6 +783,8 @@ efi_status_t EFIAPI efi_main(efi_handle_t image_handle,
> pos = skip_whitespace(command);
> if (starts_with(pos, u"exit"))
> break;
> + else if (starts_with(pos, u"dump"))
> + do_dump();
> else if (starts_with(pos, u"load "))
> do_load(pos + 5);
> else if (starts_with(pos, u"save "))
> --
> 2.45.2
>
Acked-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
Tested-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
