[U-Boot] [U-Boot, v3, 07/11] spl: add support to booting with OP-TEE

[Philipp Tomsich]

On Tue, 19 Dec 2017, Kever Yang wrote:

> OP-TEE is an open source trusted OS, in armv7, its loading and
> running are like this:
> loading:
> - SPL load both OP-TEE and U-Boot
> running:
> - SPL run into OP-TEE in secure mode;
> - OP-TEE run into U-Boot in non-secure mode;
>
> More detail:
> https://github.com/OP-TEE/optee_os
> and search for 'boot arguments' for detail entry parameter in:
> core/arch/arm/kernel/generic_entry_a32.S
>
> Signed-off-by: Kever Yang <kever.yang at rock-chips.com>

Reviewed-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>

See below for requested changed.

> ---
>
> Changes in v3: None
> Changes in v2:
> - Using new image type for op-tee
>
> common/spl/Kconfig     |  7 +++++++
> common/spl/Makefile    |  1 +
> common/spl/spl.c       |  8 ++++++++
> common/spl/spl_optee.S | 13 +++++++++++++
> include/spl.h          |  9 +++++++++
> 5 files changed, 38 insertions(+)
> create mode 100644 common/spl/spl_optee.S
>
> diff --git a/common/spl/Kconfig b/common/spl/Kconfig
> index aef0034..c9a1ebb 100644
> --- a/common/spl/Kconfig
> +++ b/common/spl/Kconfig
> @@ -725,6 +725,13 @@ config SPL_ATF
> 	  is loaded by SPL(which is considered as BL2 in ATF terminology).
> 	  More detail at: https://github.com/ARM-software/arm-trusted-firmware
>
> +config SPL_OPTEE
> +	bool "Support OP-TEE Trusted OS"
> +	depends on ARM
> +	help
> +	  OP-TEE is an open source Trusted OS  which is loaded by SPL.
> +	  More detail at: https://github.com/OP-TEE/optee_os
> +
> config TPL
> 	bool
> 	depends on SUPPORT_TPL
> diff --git a/common/spl/Makefile b/common/spl/Makefile
> index 9bf8a2d..9918a2e 100644
> --- a/common/spl/Makefile
> +++ b/common/spl/Makefile
> @@ -23,6 +23,7 @@ obj-$(CONFIG_$(SPL_TPL_)UBI) += spl_ubi.o
> obj-$(CONFIG_$(SPL_TPL_)NET_SUPPORT) += spl_net.o
> obj-$(CONFIG_$(SPL_TPL_)MMC_SUPPORT) += spl_mmc.o
> obj-$(CONFIG_$(SPL_TPL_)ATF) += spl_atf.o
> +obj-$(CONFIG_$(SPL_TPL_)OPTEE) += spl_optee.o
> obj-$(CONFIG_$(SPL_TPL_)USB_SUPPORT) += spl_usb.o
> obj-$(CONFIG_$(SPL_TPL_)FAT_SUPPORT) += spl_fat.o
> obj-$(CONFIG_$(SPL_TPL_)EXT_SUPPORT) += spl_ext.o
> diff --git a/common/spl/spl.c b/common/spl/spl.c
> index 76c1963..2c8942b 100644
> --- a/common/spl/spl.c
> +++ b/common/spl/spl.c
> @@ -436,6 +436,12 @@ void board_init_r(gd_t *dummy1, ulong dummy2)
> 		spl_invoke_atf(&spl_image);
> 		break;
> #endif
> +#if CONFIG_IS_ENABLED(OPTEE)
> +	case IH_OS_OP_TEE:
> +		debug("Jumping to U-Boot via OP-TEE\n");
> +		spl_optee_entry(0, 0, 0, (void *)spl_image.entry_point);

Why are you passing '0' for "arg2, device tree address"? This should
be the device-tree pointer from the spl_image...

Also: 0 is not the same as NULL ... the arguments are all defined to
have void* type, so 0 is not the correct type.

> +		break;
> +#endif
> #ifdef CONFIG_SPL_OS_BOOT
> 	case IH_OS_LINUX:
> 		debug("Jumping to Linux\n");
> @@ -450,6 +456,8 @@ void board_init_r(gd_t *dummy1, ulong dummy2)
> 	debug("SPL malloc() used %#lx bytes (%ld KB)\n", gd->malloc_ptr,
> 	      gd->malloc_ptr / 1024);
> #endif
> +
> +	debug("loaded - jumping to U-Boot...\n");
> #ifdef CONFIG_BOOTSTAGE_STASH
> 	int ret;
>
> diff --git a/common/spl/spl_optee.S b/common/spl/spl_optee.S
> new file mode 100644
> index 0000000..4f7f8ba
> --- /dev/null
> +++ b/common/spl/spl_optee.S
> @@ -0,0 +1,13 @@
> +/*
> + * Copyright (C) 2017 Rockchip Electronic Co.,Ltd
> + *
> + * SPDX-License-Identifier:	GPL-2.0+
> + */
> +
> +#include <linux/linkage.h>
> +#include <asm/assembler.h>
> +
> +ENTRY(spl_optee_entry)
> +	ldr lr, =CONFIG_SYS_TEXT_BASE
> +	mov pc, r3
> +ENDPROC(spl_optee_entry)
> diff --git a/include/spl.h b/include/spl.h
> index c14448b..551ce43 100644
> --- a/include/spl.h
> +++ b/include/spl.h
> @@ -288,6 +288,15 @@ int spl_mmc_load_image(struct spl_image_info *spl_image,
> void spl_invoke_atf(struct spl_image_info *spl_image);
>
> /**
> + * spl_optee_entry - entry function for optee
> + * entry arg0, pagestore
> + * entry arg1, (ARMv7 standard bootarg #1)
> + * entry arg2, device tree address, (ARMv7 standard bootarg #2)
> + * entry arg3, non-secure entry address (ARMv7 bootarg #0)
> + */
> +void spl_optee_entry(void *arg0, void *arg1, void *arg2, void *arg3);

This doesn't look like a documentation comment for a U-Boot function.
Also: the purpose of arg0 and arg1 are not clear from this comment.

> +
> +/**
>  * board_return_to_bootrom - allow for boards to continue with the boot ROM
>  *
>  * If a board (e.g. the Rockchip RK3368 boards) provide some
>