On Tue, Jan 29, 2019 at 11:16 PM Rouven Czerwinski <r.czerwinski@xxxxxxxxxxxxxx> wrote: > > On Tue, 2019-01-29 at 14:35 -0800, Andrey Smirnov wrote: > > On Tue, Jan 29, 2019 at 3:11 AM Rouven Czerwinski > > <r.czerwinski@xxxxxxxxxxxxxx> wrote: > > > > > > From: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> > > > > > > This adds initial support for OP-TEE, see https://www.op-tee.org/ > > > > > > barebox starts in secure mode as usual. When booting a kernel > > > the bootm code also loads the optee_os binary. Instead of jumping > > > into the kernel barebox jumps into the optee_os binary and puts > > > the kernel execution address into the lr register. OP-TEE then > > > jumps into the kernel in nonsecure mode. > > > > > > The optee_os binary is passed with the -t option to bootm or > > > with global.bootm.tee. > > > > > > Optionally OP-TEE can be compiled into barebox using the builtin > > > firmware > > > feature. Enable the Kconfig option and place or link your tee > > > binary as > > > optee.bin into the firmware directory. > > > > > > The amount of SDRAM which is kept free for OP-TEE is configurable. > > > > > > This patch was tested on a i.MX6 Nitrogen6x board. > > > > > > Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> > > > Signed-off-by: Rouven Czerwinski <r.czerwinski@xxxxxxxxxxxxxx> > > > --- > > > arch/arm/cpu/Makefile | 2 +- > > > arch/arm/cpu/start-kernel-optee.S | 14 ++++- > > > arch/arm/cpu/start.c | 3 +- > > > arch/arm/include/asm/armlinux.h | 2 +- > > > arch/arm/include/asm/barebox-arm.h | 9 ++- > > > arch/arm/lib32/armlinux.c | 10 ++- > > > arch/arm/lib32/bootm.c | 109 > > > +++++++++++++++++++++++++++++- > > > arch/arm/lib32/bootu.c | 2 +- > > > arch/arm/lib32/bootz.c | 2 +- > > > commands/bootm.c | 11 ++- > > > common/Kconfig | 33 +++++++++- > > > common/bootm.c | 6 ++- > > > firmware/Kconfig | 3 +- > > > firmware/Makefile | 2 +- > > > include/bootm.h | 3 +- > > > include/tee/optee.h | 30 ++++++++- > > > 16 files changed, 234 insertions(+), 7 deletions(-) > > > create mode 100644 arch/arm/cpu/start-kernel-optee.S > > > create mode 100644 include/tee/optee.h > > > > > > diff --git a/arch/arm/cpu/Makefile b/arch/arm/cpu/Makefile > > > index a35db43..e6e74e0 100644 > > > --- a/arch/arm/cpu/Makefile > > > +++ b/arch/arm/cpu/Makefile > > > @@ -12,6 +12,8 @@ obj-y += start.o entry.o > > > > > > obj-pbl-y += setupc$(S64).o cache$(S64).o > > > > > > +obj-$(CONFIG_BOOTM_OPTEE) += start-kernel-optee.o > > > + > > > # > > > # Any variants can be called as start-armxyz.S > > > # > > > diff --git a/arch/arm/cpu/start-kernel-optee.S > > > b/arch/arm/cpu/start-kernel-optee.S > > > new file mode 100644 > > > index 0000000..ce5ac17 > > > --- /dev/null > > > +++ b/arch/arm/cpu/start-kernel-optee.S > > > @@ -0,0 +1,14 @@ > > > +#include <linux/linkage.h> > > > + > > > +ENTRY(start_kernel_optee) > > > + /* > > > + * r0 = optee > > > + * r1 = kernel > > > + * r2 = oftree > > > + */ > > > + mov r4, r0 > > > + mov r0, #0 > > > + mov lr, r1 > > > + mov r1, #0 > > > + bx r4 > > > +ENDPROC(start_kernel_optee) > > > diff --git a/arch/arm/cpu/start.c b/arch/arm/cpu/start.c > > > index 768fa9e..e78a820 100644 > > > --- a/arch/arm/cpu/start.c > > > +++ b/arch/arm/cpu/start.c > > > @@ -226,6 +226,9 @@ __noreturn void barebox_non_pbl_start(unsigned > > > long membase, > > > > > > mem_malloc_init((void *)malloc_start, (void *)malloc_end - > > > 1); > > > > > > + if (IS_ENABLED(CONFIG_BOOTM_OPTEE)) > > > + of_add_reserve_entry(endmem - > > > CONFIG_BOOTM_OPTEE_SIZE, endmem - 1); > > > + > > > pr_debug("starting barebox...\n"); > > > > > > start_barebox(); > > > diff --git a/arch/arm/include/asm/armlinux.h > > > b/arch/arm/include/asm/armlinux.h > > > index 135f11b..6af9896 100644 > > > --- a/arch/arm/include/asm/armlinux.h > > > +++ b/arch/arm/include/asm/armlinux.h > > > @@ -40,6 +40,6 @@ struct image_data; > > > > > > void start_linux(void *adr, int swap, unsigned long > > > initrd_address, > > > unsigned long initrd_size, void *oftree, > > > - enum arm_security_state); > > > + enum arm_security_state, void *optee); > > > > > > #endif /* __ARCH_ARMLINUX_H */ > > > diff --git a/arch/arm/include/asm/barebox-arm.h > > > b/arch/arm/include/asm/barebox-arm.h > > > index e065b47..95765f9 100644 > > > --- a/arch/arm/include/asm/barebox-arm.h > > > +++ b/arch/arm/include/asm/barebox-arm.h > > > @@ -109,6 +109,15 @@ void *barebox_arm_boot_dtb(void); > > > static inline unsigned long arm_mem_stack_top(unsigned long > > > membase, > > > unsigned long endmem) > > > { > > > + /* > > > + * FIXME: > > > + * OP-TEE expects to be executed somewhere at the end of > > > RAM. > > > + * Since we normally occupy all RAM at the end, move > > > ourselves > > > + * a bit lower. > > > + */ > > > + if (IS_ENABLED(CONFIG_BOOTM_OPTEE)) > > > + return endmem - CONFIG_BOOTM_OPTEE_SIZE - SZ_64K; > > > > You can probably change it to: > > > > if (IS_ENABLED(CONFIG_BOOTM_OPTEE)) > > endmem -= CONFIG_BOOTM_OPTEE_SIZE; > > > > to avoid hard-coding SZ_64K in two places > > > sensible, will fix. > > > > + > > > return endmem - SZ_64K; > > > } > > > > > > diff --git a/arch/arm/lib32/armlinux.c b/arch/arm/lib32/armlinux.c > > > index c970f02..a1e3375 100644 > > > --- a/arch/arm/lib32/armlinux.c > > > +++ b/arch/arm/lib32/armlinux.c > > > @@ -258,9 +258,11 @@ static void setup_tags(unsigned long > > > initrd_address, > > > > > > } > > > > > > +void start_kernel_optee(void *optee, void *kernel, void *oftree); > > > + > > > void start_linux(void *adr, int swap, unsigned long > > > initrd_address, > > > unsigned long initrd_size, void *oftree, > > > - enum arm_security_state state) > > > + enum arm_security_state state, void *optee) > > > { > > > void (*kernel)(int zero, int arch, void *params) = adr; > > > void *params = NULL; > > > @@ -294,5 +296,9 @@ void start_linux(void *adr, int swap, unsigned > > > long initrd_address, > > > __asm__ __volatile__("mcr p15, 0, %0, c1, c0" :: > > > "r" (reg)); > > > } > > > > > > - kernel(0, architecture, params); > > > + if (optee) { > > > + start_kernel_optee(optee, kernel, oftree); > > > + } else { > > > + kernel(0, architecture, params); > > > + } > > > > Just out of curiosity, can we return back to this function in > > non-secure mode and just do: > > > > if (optee) > > optee(); > > kernel(0, architecture, params); > > > > ? > I don't quite get your intention here. We can't start OP-TEE in non- > secure mode and at least currently OP-TEE starts without returning back > to barebox. > AFAICT the reason start_kernel_optee() exists is to initialize LR with desired return address and facilitate starting kernel without returning to Barebox. What I am trying to figure out is why of if the "without returning" part is important. Can the OP-TEE start sequence be modified to just execute OP-TEE, return back to the original caller and then jump to kernel in a separate step? IOW, can start_kernel_optee() be dropped and OP-TEE initialized via a regular C-call? > > > > > } > > > diff --git a/arch/arm/lib32/bootm.c b/arch/arm/lib32/bootm.c > > > index 4cf570e..69bf5bb 100644 > > > --- a/arch/arm/lib32/bootm.c > > > +++ b/arch/arm/lib32/bootm.c > > > @@ -4,6 +4,7 @@ > > > #include <command.h> > > > #include <driver.h> > > > #include <environment.h> > > > +#include <firmware.h> > > > #include <image.h> > > > #include <init.h> > > > #include <fs.h> > > > @@ -19,6 +20,7 @@ > > > #include <binfmt.h> > > > #include <restart.h> > > > #include <globalvar.h> > > > +#include <tee/optee.h> > > > > > > #include <asm/byteorder.h> > > > #include <asm/setup.h> > > > @@ -133,11 +135,96 @@ static int get_kernel_addresses(size_t > > > image_size, > > > return 0; > > > } > > > > > > +static int optee_verify_header_request_region(struct image_data > > > *data, struct optee_header *hdr) > > > +{ > > > + int ret; > > > > This function uses "ret" in some really superfluous way. I'd consider > > just dropping "ret". > yes, will fix. > > > > > > + > > > + if (hdr->magic != OPTEE_MAGIC) { > > > + printf("Invalid header magic 0x%08x, expected > > > 0x%08x\n", > > > + hdr->magic, OPTEE_MAGIC); > > > + ret = -EINVAL; > > > + return ret; > > > + } > > > + > > > + if (hdr->arch != OPTEE_ARCH_ARM32 || hdr- > > > >init_load_addr_hi) { > > > + printf("Only 32bit supported\n"); > > > + ret = -EINVAL; > > > + return ret; > > > + } > > > + > > > + data->tee_res = request_sdram_region("TEE", hdr- > > > >init_load_addr_lo, hdr->init_size); > > > + if (!data->tee_res) { > > > + ret = -EBUSY; > > > > Underlying call to __request_region() in request_sdram_region() can > > also return -EINVAL if, for example, requested region is too big. I > > don't think hard-coding -EBUSY, really adds any useful info here. > will fix. > > > > + printf("Cannot request SDRAM region 0x%08x-0x%08x: > > > %s\n", > > > + hdr->init_load_addr_lo, hdr- > > > >init_load_addr_lo + hdr->init_size - 1, > > > + strerror(-ret)); > > > + } > > > + > > > + ret = 0; > > > + return ret; > > > +} > > > + > > > +static int bootm_load_tee_from_firmware(struct image_data *data) > > > +{ > > > + int ret; > > > + > > > + u8 *optee; > > > + size_t optee_size; > > > + > > > + struct optee_header hdr; > > > + > > > + get_builtin_firmware(optee_bin, &optee, &optee_size); > > > + > > > + memcpy(optee, &hdr, sizeof(hdr)); > > > + > > > + ret = optee_verify_header_request_region(data, &hdr); > > > + if (ret < 0) > > > + return ret; > > > + > > > + memcpy(optee, (void *)data->tee_res->start, hdr.init_size); > > > + > > > + printf("Copied optee binary to 0x%08x, size 0x%08x\n", > > > data->tee_res->start, hdr.init_size); > > > + > > > + ret = 0; > > > + return ret; > > > +} > > > > What if we instead do: > > > > get_builtin_firmware(optee_bin, &optee, &optee_size); > > add_mem_device("optee", optee, optee_size, 0); > > > > and then handle that case via "/dev/optee" and > > bootm_load_tee_from_file()? Is there any reason it wouldn't work? > Thats a good idea to expose the idea and simplify the tee loading code. > > > Moreso, if that can be done we should consider just providing an API > > to handle built-in firmware case and delegating that job to > > individual > > board files, so that we have the freedom of having per-board version > > of OP-TEE firmware. > The idea here was to not include the OP-TEE binary into the barebox > upstream repository and only provide the option to include optee for > production devices. > I can't think of a use case where we want to include OP-TEE into an > upstream barebox, since the features for OP-TEE (included early TAs, > memory size,...) are quite specific for the use case. > Even if OP-TEE blob is never shipped in upstream repo, it seems that it is entirely possible to have a use-case where user would have two+ boards of the same CPU architecture requiring different OP-TEE blobs. Or is it a scenario that just doesn't exist in real-life? What I am trying to say is that right now there's a central place where get_builtin_firmware() is called that, besides hard-coding a single OP-TEE binary, also requires a Kconfig option to be optional. It seems that providing a simple macro like say: #define export_builtin_firmware(fw, name) \ do { \ const u8 *__blob; \ size_t __size; \ get_builtin_firmware(fw, &__blob, &__size); \ add_mem_device(name, __blob, __size, 0); \ } while (0) and leaving the job of calling that to individual board code will allow you to drop extra Kconfig code and support multi or single built-in OP-TEE builds. Thanks, Andrey Smirnov _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
