Add support for starting TFA from U-Boot running in EL3 as part of fitImage boot, so the user can start U-Boot in the highest privilege level on the platform, bundle TFA, Linux, DT into a single fitImage and boot such a bundle as a whole.
There are two main benefits of this approach. First is the ability to run U-Boot in EL3, where it has unrestricted access to the entire system and can act as a useful debug tool, as it was always intended to be used. Second is the ability to easily and safely update of any component in the fitImage, be it TFA, Linux or DT.
The boot process is similar to regular Linux with DT fitImage boot process, except the TFA has to be bundled into the fitImage. For the bundling instructions, see below. The TFA is started as a 'loadables' with custom U_BOOT_FIT_LOADABLE_HANDLER and armv8_switch_to_el2_prep() handling implemented in board code, and performing the handoff and boot in case the TFA was loaded.
The loadables handler is optional and meant to set up any sort of handoff structures used by the TFA BL31 or perform any other setup that is needed by the blob. The custom armv8_switch_to_el2_prep() has to implement the jump to TFA BL31 with return to U-Boot just before booting the Linux kernel.
Example fitImage image and configuration section:
/dts-v1/;
/ { description = "Linux kernel with FDT blob and TFA BL31";
images { kernel-1 { ... }; fdt-1 { ... }; atf-1 { /* This is the TFA BL31 image */ description = "TFA BL31"; data = /incbin/("../build/plat/release/bl31.bin"); type = "tfa-bl31"; arch = "arm64"; os = "arm-trusted-firmware"; compression = "none"; load = <0x46400000>; entry = <0x46400000>; }; };
configurations { default = "conf-1"; conf-1 { description = "Boot Linux"; kernel = "kernel-1"; fdt = "fdt-1"; loadables = "atf-1"; /* This is the TFA BL31 loadable */ }; }; };
Signed-off-by: Marek Vasut marek.vasut+renesas@mailbox.org --- Cc: Andre Przywara andre.przywara@arm.com Cc: Caleb Connolly caleb.connolly@linaro.org Cc: Igor Opaniuk igor.opaniuk@gmail.com Cc: Ilias Apalodimas ilias.apalodimas@linaro.org Cc: Julien Masson jmasson@baylibre.com Cc: Mattijs Korpershoek mkorpershoek@baylibre.com Cc: Maxim Moskalets maximmosk4@gmail.com Cc: Michael Walle mwalle@kernel.org Cc: Nobuhiro Iwamatsu iwamatsu@nigauri.org Cc: Patrick Rudolph patrick.rudolph@9elements.com Cc: Paul Barker paul.barker.ct@bp.renesas.com Cc: Paul-Erwan Rio paulerwan.rio@gmail.com Cc: Peter Hoyes Peter.Hoyes@arm.com Cc: Raymond Mao raymond.mao@linaro.org Cc: Sam Protsenko semen.protsenko@linaro.org Cc: Simon Glass sjg@chromium.org Cc: Sughosh Ganu sughosh.ganu@linaro.org Cc: Tom Rini trini@konsulko.com Cc: u-boot@lists.denx.de --- boot/image-fit.c | 1 + boot/image.c | 1 + include/image.h | 1 + 3 files changed, 3 insertions(+)
diff --git a/boot/image-fit.c b/boot/image-fit.c index 7d56f0b5e6e..9ee98bef817 100644 --- a/boot/image-fit.c +++ b/boot/image-fit.c @@ -2166,6 +2166,7 @@ int fit_image_load(struct bootm_headers *images, ulong addr, type_ok = fit_image_check_type(fit, noffset, image_type) || fit_image_check_type(fit, noffset, IH_TYPE_FIRMWARE) || fit_image_check_type(fit, noffset, IH_TYPE_TEE) || + fit_image_check_type(fit, noffset, IH_TYPE_TFA_BL31) || (image_type == IH_TYPE_KERNEL && fit_image_check_type(fit, noffset, IH_TYPE_KERNEL_NOLOAD));
diff --git a/boot/image.c b/boot/image.c index abac254e026..139c5bd035a 100644 --- a/boot/image.c +++ b/boot/image.c @@ -183,6 +183,7 @@ static const table_entry_t uimage_type[] = { { IH_TYPE_FDT_LEGACY, "fdt_legacy", "legacy Image with Flat Device Tree ", }, { IH_TYPE_RENESAS_SPKG, "spkgimage", "Renesas SPKG Image" }, { IH_TYPE_STARFIVE_SPL, "sfspl", "StarFive SPL Image" }, + { IH_TYPE_TFA_BL31, "tfa-bl31", "TFA BL31 Image", }, { -1, "", "", }, };
diff --git a/include/image.h b/include/image.h index 9be5acd8158..90bd88ab3c2 100644 --- a/include/image.h +++ b/include/image.h @@ -232,6 +232,7 @@ enum image_type_t { IH_TYPE_FDT_LEGACY, /* Binary Flat Device Tree Blob in a Legacy Image */ IH_TYPE_RENESAS_SPKG, /* Renesas SPKG image */ IH_TYPE_STARFIVE_SPL, /* StarFive SPL image */ + IH_TYPE_TFA_BL31, /* TFA BL31 image */
IH_TYPE_COUNT, /* Number of image types */ };