On 1/18/26 8:58 PM, Marco Felsch wrote:
> On 26-01-15, Ahmad Fatoum wrote:
>> Hello Marco,
>>
>> On 11/10/25 9:34 PM, Marco Felsch wrote:
>>> Add a helper to extract the added OP-TEE FDT overlay fragments from the
>>> FDT provided via arg2 during the boot phase into a dedicated buffer.
>>>
>>> The dedicated overlay buffer can be used later on by the PBL code to
>>> apply the overlay to the barebox runtime DTB and to the kernel DTB.
>>>
>>> Signed-off-by: Marco Felsch <[email protected]>
>>> ---
>>> include/tee/optee.h | 6 ++++++
>>> security/optee.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
>>> 2 files changed, 50 insertions(+)
>>>
>>> diff --git a/include/tee/optee.h b/include/tee/optee.h
>>> index
>>> 10e829c04f8832c4c04771800f1963e25f425482..679662a6e6944da59d24d6268ebcf5dff19d0980
>>> 100644
>>> --- a/include/tee/optee.h
>>> +++ b/include/tee/optee.h
>>> @@ -37,6 +37,7 @@ int optee_verify_header (const struct optee_header *hdr);
>>>
>>> void optee_set_membase(const struct optee_header *hdr);
>>> int optee_get_membase(u64 *membase);
>>> +int optee_extract_fdto(const void *fdt, void *fdto, unsigned int fdto_sz);
>>>
>>> #else
>>>
>>> @@ -49,6 +50,11 @@ static inline int optee_get_membase(u64 *membase)
>>> return -ENOSYS;
>>> }
>>>
>>> +static inline int optee_extract_fdto(const void *fdt, void *fdto, unsigned
>>> int fdto_sz)
>>> +{
>>> + return 0;
>>> +}
>>> +
>>> #endif /* CONFIG_HAVE_OPTEE */
>>>
>>> #ifdef __PBL__
>>> diff --git a/security/optee.c b/security/optee.c
>>> index
>>> 422bc1c90924ba8ab266b1aa8d06e52c819d2010..3750bb6f496af990d77f3629b470b174dd7a7c7a
>>> 100644
>>> --- a/security/optee.c
>>> +++ b/security/optee.c
>>> @@ -5,7 +5,9 @@
>>> #include <tee/optee.h>
>>> #include <linux/printk.h>
>>> #include <linux/errno.h>
>>> +#include <linux/libfdt.h>
>>> #include <linux/limits.h>
>>> +#include <pbl.h>
>>>
>>> static u64 optee_membase = U64_MAX;
>>>
>>> @@ -60,3 +62,45 @@ void optee_set_membase(const struct optee_header *hdr)
>>> optee_membase = (u64)hdr->init_load_addr_hi << 32;
>>> optee_membase |= hdr->init_load_addr_lo;
>>> }
>>> +
>>> +int optee_extract_fdto(const void *fdt, void *fdto, unsigned int fdto_sz)
>>> +{
>>> + int err;
>>> + int subnode;
>>> +
>>> + err = fdt_check_header(fdt);
>>> + if (err) {
>>> + pr_err("Invalid device tree blob: %s\n", fdt_strerror(err));
>>> + return err;
>>> + }
>>> +
>>> + err = fdt_create_empty_tree(fdto, fdto_sz);
>>> + if (err) {
>>> + pr_err("Failed to initialize OP-TEE FDTO space: %s\n",
>>> fdt_strerror(err));
>>> + return err;
>>> + }
>>> +
>>> + fdt_for_each_subnode(subnode, fdt, 0) {
>>> + const char *name;
>>> + int len;
>>> +
>>> + name = fdt_get_name(fdt, subnode, &len);
>>> + if (!name) {
>>> + pr_warn("Failed to query FDT node name: %s\n",
>>> fdt_strerror(len));
>>> + continue;
>>> + }
>>> +
>>> + if (strncmp(name, "fragment@", 9) != 0) {
>>> + pr_debug("Skip node %s\n", name);
>>> + continue;
>>> + }
>>> +
>>> + err |= fdt_copy_node(fdt, fdto, "/", name);
>>
>> Aren't these sequential error codes? OR'ing them will produce a
>> non-sensical error code if there are different error codes returned.
>
> That's true.
>
>> Better change to:
>>
>> ret = fdt_copy_node(fdt, fdto, "/", name);
>> if (ret)
>> err = ret;
>
> Hm, but this would hide previous errors too. Of course we could break
> the loop in the error case. I will add this to the v2.
Any valid error code is better than OR-ing multiple invalid error codes.
I am fine wither either early exit or just returning a single error.
Cheers,
Ahmad
>
>> with err being initialized as zero.
>
> Sure.
>
> Regards,
> Marco
>
>>
>>> + }
>>> +
>>> + /* Clear the FDTO memory to not supply incomplete overlays */
>>> + if (err)
>>> + memset(fdto, 0, fdto_sz);
>>> +
>>> + return err;
>>> +}
>>>
>>
>> --
>> Pengutronix e.K. | |
>> Steuerwalder Str. 21 | http://www.pengutronix.de/ |
>> 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
>> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
>>
>>
>
--
Pengutronix e.K. | |
Steuerwalder Str. 21 | http://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
