The upstream OP-TEE expects a device tree to be able to initialize the
dynamic shared memory. Therefore, barebox should pass a device tree that
contains memory nodes through the TF-A to OP-TEE.
OP-TEE may modify the passed fdt. Thus, barebox copies the fdt from the
fixed size rodata area to the rk_scratch area and allocates a
configurable memory area for the fdt to allow fdt modification.
OP-TEE has the CFG_DTB_MAX_SIZE config option for the maximum size of
the fdt. barebox must reserve at least that much memory for the fdt to
avoid out of bounds accesses from OP-TEE.
Unfortunately, the downstream TF-A fails to start if barebox passes its
device tree and it is not possible to detect if the loaded TF-A is able
to handle the device tree. Add a config option to pass the device tree
if it is possible.
Signed-off-by: Michael Tretter <m.tret...@pengutronix.de>
---
Changes in v2:
- pass copy of fdt in scratch space to TF-A
- add config option for fdt size
- add documentation for CONFIG_ARCH_ROCKCHIP_ATF_PASS_FDT
---
Documentation/boards/rockchip.rst | 4 ++++
arch/arm/mach-rockchip/Kconfig | 23 +++++++++++++++++++++++
arch/arm/mach-rockchip/atf.c | 24 ++++++++++++------------
include/mach/rockchip/bootrom.h | 3 +++
4 files changed, 42 insertions(+), 12 deletions(-)
diff --git a/Documentation/boards/rockchip.rst
b/Documentation/boards/rockchip.rst
index
b2b04abb03cd1926bb59799af5f6a8c11d410cc2..8bce92865e3eda193412180c7295b5a35b3531e8
100644
--- a/Documentation/boards/rockchip.rst
+++ b/Documentation/boards/rockchip.rst
@@ -94,6 +94,10 @@ With these barebox can be compiled as:
.. note:: The RK3566 and RK3568 seem to share the bl31 and bl32 firmware files,
whereas the memory initialization blob is different.
+.. note:: The bl31 from the rkbin repository seems to be unable to handle
+ device trees of a larger size (for example, if CONFIG_OF_OVERLAY_LIVE is
+ enabled). Disable CONFIG_ARCH_ROCKCHIP_ATF_PASS_FDT in this case.
+
Creating a bootable SD card
---------------------------
diff --git a/arch/arm/mach-rockchip/Kconfig b/arch/arm/mach-rockchip/Kconfig
index
98dfd11c182b9fee6e3c958653ad4fa8a7d98d84..1b72dc4b8a16ce9dca742ff1173fc2208a0e619d
100644
--- a/arch/arm/mach-rockchip/Kconfig
+++ b/arch/arm/mach-rockchip/Kconfig
@@ -141,6 +141,29 @@ config ARCH_ROCKCHIP_ATF
useful for debugging early startup, but for all other cases,
say y here.
+config ARCH_ROCKCHIP_ATF_PASS_FDT
+ bool "Pass device tree to TF-A"
+ depends on ARCH_ROCKCHIP_ATF
+ help
+ Enable this option if you are using an upstream OP-TEE that uses the
+ device tree to initialize dynamic shared memory, which is passed
+ through the upstream TF-A.
+
+ Disable the option if you are using a downstream TF-A since it
+ doesn't always cope with device trees. Supposedly this happens if the
+ device tree is too large, for example if CONFIG_OF_OVERLAY_LIVE is
+ enabled.
+
+config ARCH_ROCKCHIP_ATF_FDT_SIZE
+ hex
+ default 0x0
+ default 0x60000 if ARCH_ROCKCHIP_ATF_PASS_FDT
+ prompt "Reserved size for the FDT blob passed to the TF-A"
+ help
+ Set this size to CFG_DTB_MAX_SIZE in the OP-TEE configuration. OP-TEE
+ may modify the passed device tree and increase it's size. This
+ ensures that barebox reserves enough memory for the modifications.
+
config ARCH_ROCKCHIP_OPTEE
bool "Build rockchip OP-TEE binary into barebox"
depends on ARCH_ROCKCHIP_ATF
diff --git a/arch/arm/mach-rockchip/atf.c b/arch/arm/mach-rockchip/atf.c
index
cfa6df043b34c0f36919048237c7ecf33dfe0724..f4a71ef2dc8dffc6ceb4f97ee542f5b83858120b
100644
--- a/arch/arm/mach-rockchip/atf.c
+++ b/arch/arm/mach-rockchip/atf.c
@@ -183,21 +183,21 @@ void __noreturn rk3588_barebox_entry(void *fdt)
rk_scratch = (void *)arm_mem_scratch(endmem);
if (current_el() == 3) {
+ void *fdt_scratch = NULL;
+
rk3588_lowlevel_init();
rockchip_store_bootrom_iram(IOMEM(RK3588_IRAM_BASE));
- /*
- * The downstream TF-A doesn't cope with our device tree when
- * CONFIG_OF_OVERLAY_LIVE is enabled, supposedly because it is
- * too big for some reason. Otherwise it doesn't have any
visible
- * effect if we pass a device tree or not, except that the TF-A
- * fills in the ethernet MAC address into the device tree.
- * The upstream TF-A doesn't use the device tree at all.
- *
- * Pass NULL for now until we have a good reason to pass a real
- * device tree.
- */
- rk3588_atf_load_bl31(NULL);
+#ifdef CONFIG_ARCH_ROCKCHIP_ATF_PASS_FDT
+ pr_debug("Copy fdt to scratch area 0x%p (%zu bytes)\n",
+ rk_scratch->fdt, sizeof(rk_scratch->fdt));
+ if (fdt_open_into(fdt, rk_scratch->fdt,
sizeof(rk_scratch->fdt)) == 0)
+ fdt_scratch = rk_scratch->fdt;
+ else
+ pr_warn("Failed to copy fdt to scratch: Continue
without fdt\n");
+#endif
+
+ rk3588_atf_load_bl31(fdt_scratch);
/* not reached when CONFIG_ARCH_ROCKCHIP_ATF */
}
diff --git a/include/mach/rockchip/bootrom.h b/include/mach/rockchip/bootrom.h
index
6776ac5ef9813de903f936e340afd72ecd417c82..586008a78505943c968301a9ce90ed5e4aa9b18b
100644
--- a/include/mach/rockchip/bootrom.h
+++ b/include/mach/rockchip/bootrom.h
@@ -13,7 +13,10 @@
struct rockchip_scratch_space {
u32 irom[16];
struct optee_header optee_hdr;
+ /* FDT needs an 8 byte alignment */
+ u8 fdt[CONFIG_ARCH_ROCKCHIP_ATF_FDT_SIZE] __aligned(8);
};
+static_assert(sizeof(struct rockchip_scratch_space) <= CONFIG_SCRATCH_SIZE);
extern struct rockchip_scratch_space *rk_scratch;
--
2.39.5
