Merge changes I0396b597,I326f920f,I0437eec8,Ieadf01fc,I4e1d8c24, ... into integration

* changes: feat(fvp): set defaults for build commandline docs(arm): enable Linux boot from fip as BL33 feat(arm): enable Linux boot from fip as BL33 docs(fvp): update fvp build time options docs(arm): add initrd props to dtb at build time feat(arm): add initrd props to dtb at build time
2025-04-07 21:33:54 +00:00 · 2025-03-04 17:13:46 +01:00 · 2025-03-04 17:13:46 +01:00 · 183f2ea2fe
commit 183f2ea2fe
parent 4d6315e9a6 bf9a25f075
6 changed files with 138 additions and 66 deletions
--- a/15
+++ b/15
@ -1638,6 +1638,21 @@ endif #(NEED_BL2U)
 # Expand build macros for the different images
 ifeq (${NEED_FDT},yes)
    $(eval $(call MAKE_DTBS,$(BUILD_PLAT)/fdts,$(FDT_SOURCES)))
+
+    ifneq (${INITRD_SIZE}${INITRD_PATH},)
+        ifndef INITRD_BASE
+            $(error INITRD_BASE must be set when inserting initrd properties to the DTB.)
+        endif
+
+        INITRD_SIZE ?= $(shell printf "0x%x\n" $$(stat -Lc %s $(INITRD_PATH)))
+        initrd_end = $(shell printf "0x%x\n" $$(expr $$(($(INITRD_BASE) + $(INITRD_SIZE)))))
+
+        define $(HW_CONFIG)-after +=
+            $(s)echo "  INITRD  $(HW_CONFIG)"
+            $(q)fdtput -t x $@ /chosen linux,initrd-start $(INITRD_BASE)
+            $(q)fdtput -t x $@ /chosen linux,initrd-end $(initrd_end)
+        endef
+    endif
 endif #(NEED_FDT)

 # Add Secure Partition packages
--- a/docs/plat/arm/fvp/fvp-build-options.rst
+++ b/docs/plat/arm/fvp/fvp-build-options.rst
@ -46,6 +46,16 @@ Arm FVP Platform Specific Build Options
   is ``0``, which means the redistributor pages of all CPU cores are marked
   as read and write.

+-  ``INITRD_SIZE`` : Enable the insertion of initrd properties to the device
+   tree blob at build time. Takes an initrd size value in hex format
+
+-  ``INITRD_PATH`` : Enable the insertion of initrd properties to the device tree
+   blob at build time. Takes a path to an initrd file. Can be used as an
+   alternative to ``INITRD_SIZE``. ``INITRD_SIZE`` takes precedence over
+   ``INITRD_PATH`` if both values are provided.
+
+-  ``INITRD_BASE`` : Provide the preloaded initrd base address in memory (hex format).
+
 --------------

-*Copyright (c) 2019-2024, Arm Limited. All rights reserved.*
+*Copyright (c) 2019-2025, Arm Limited. All rights reserved.*
--- a/docs/plat/arm/fvp/fvp-specific-configs.rst
+++ b/docs/plat/arm/fvp/fvp-specific-configs.rst
@ -73,85 +73,122 @@ used:
   The address provided to the FVP must match the ``EL3_PAYLOAD_BASE`` address
   used when building TF-A.

-Booting a preloaded kernel image (Base FVP)
-------------------------------------------
+Booting a kernel image in BL33
+------------------------------

-The following example uses a simplified boot flow by directly jumping from the
-TF-A to the Linux kernel, which will use a ramdisk as filesystem. This can be
-useful if both the kernel and the device tree blob (DTB) are already present in
-memory (like in FVP).
+TF-A can boot a Linux kernel, which uses a ramdisk as a filesystem. The
+required initrd properties are injected in to the device tree blob (DTB) at
+build time.

-For example, if the kernel is loaded at ``0x80080000`` and the DTB is loaded at
-address ``0x82000000``, the firmware can be built like this:
+Kernel image packaged in fip as a BL33 image
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+A Linux kernel image can be packaged in the fip as a BL33 image and then
+booted in TF-A.
+
+For example, the firmware can be built as:

 .. code:: shell

-    CROSS_COMPILE=aarch64-none-elf-  \
    make PLAT=fvp DEBUG=1             \
-    RESET_TO_BL31=1                   \
-    ARM_LINUX_KERNEL_AS_BL33=1        \
-    PRELOADED_BL33_BASE=0x80080000    \
-    ARM_PRELOADED_DTB_BASE=0x82000000 \
+    ARM_LINUX_KERNEL_AS_BL33          \
+    BL33=<path-to-kernel-binary>      \
+    INITRD_SIZE=0x8000000             \
    all fip

-Now, it is needed to modify the DTB so that the kernel knows the address of the
-ramdisk. The following script generates a patched DTB from the provided one,
-assuming that the ramdisk is loaded at address ``0x84000000``. Note that this
-script assumes that the user is using a ramdisk image prepared for U-Boot, like
-the ones provided by Linaro. If using a ramdisk without this header,the ``0x40``
-offset in ``INITRD_START`` has to be removed.
+The options ``INITRD_SIZE`` or ``INITRD_PATH`` triggers the insertion of initrd
+properties in to the DTB. ``INITRD_BASE`` is also required but a default value
+is set by the FVP platform.

-.. code:: bash
+The options available here are:

-    #!/bin/bash
+::

-    # Path to the input DTB
-    KERNEL_DTB=<path-to>/<fdt>
-    # Path to the output DTB
-    PATCHED_KERNEL_DTB=<path-to>/<patched-fdt>
-    # Base address of the ramdisk
-    INITRD_BASE=0x84000000
-    # Path to the ramdisk
-    INITRD=<path-to>/<ramdisk.img>
+    INITRD_BASE: Set the initrd base address in memory. Defaults to 0x90000000 in FVP.
+    INITRD_SIZE: Set the initrd size in dec or hex format. Hex format must precede with '0x'.
+    INITRD_PATH: Provide an initrd path for the build time to determine its exact size.

-    # Skip uboot header (64 bytes)
-    INITRD_START=$(printf "0x%x" $((${INITRD_BASE} + 0x40)) )
-    INITRD_SIZE=$(stat -Lc %s ${INITRD})
-    INITRD_END=$(printf "0x%x" $((${INITRD_BASE} + ${INITRD_SIZE})) )
+Users can provide either ``INITRD_SIZE`` or ``INITRD_PATH`` to set the initrd
+size value. ``INITRD_SIZE`` takes prioty over ``INITRD_PATH``.

-    CHOSEN_NODE=$(echo                                        \
-    "/ {                                                      \
-            chosen {                                          \
-                    linux,initrd-start = <${INITRD_START}>;   \
-                    linux,initrd-end = <${INITRD_END}>;       \
-            };                                                \
-    };")
-
-    echo $(dtc -O dts -I dtb ${KERNEL_DTB}) ${CHOSEN_NODE} |  \
-            dtc -O dtb -o ${PATCHED_KERNEL_DTB} -
-
-And the FVP binary can be run with the following command:
+Now the fvp binary can be run as:

 .. code:: shell

    <path-to>/FVP_Base_AEMv8A-AEMv8A                            \
-    -C pctl.startup=0.0.0.0                                     \
-    -C bp.secure_memory=1                                       \
-    -C cluster0.NUM_CORES=4                                     \
-    -C cluster1.NUM_CORES=4                                     \
-    -C cache_state_modelled=1                                   \
-    -C cluster0.cpu0.RVBAR=0x04001000                           \
-    -C cluster0.cpu1.RVBAR=0x04001000                           \
-    -C cluster0.cpu2.RVBAR=0x04001000                           \
-    -C cluster0.cpu3.RVBAR=0x04001000                           \
-    -C cluster1.cpu0.RVBAR=0x04001000                           \
-    -C cluster1.cpu1.RVBAR=0x04001000                           \
-    -C cluster1.cpu2.RVBAR=0x04001000                           \
-    -C cluster1.cpu3.RVBAR=0x04001000                           \
-    --data cluster0.cpu0="<path-to>/bl31.bin"@0x04001000        \
-    --data cluster0.cpu0="<path-to>/<patched-fdt>"@0x82000000   \
+    -C bp.secureflashloader.fname=<path-to>/bl1.bin             \
+    -C bp.flashloader0.fname=<path-to>/fip.bin                  \
+    --data cluster0.cpu0="<path-to>/<initrd.bin>"@0x90000000
+
+.. note::
+    Providing a higher value for an initrd size than the actual size of the file
+    is supported but it will trigger a non-breaking "Initramfs unpacking failed"
+    error by the kernel at runtime. This error can be ignored because initrd's
+    can be stacked one after another, when the kernel unpacks the first initrd it
+    looks for another in the extra space which it won't find, hence the error.
+
+Preloaded kernel image - Normal flow
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The following example uses a simplified boot flow to boot a Linux kernel
+using TF-A. This can be useful if the kernel is already present in memory
+(like in FVP).
+
+For example, if the kernel is loaded at ``0x80080000`` the firmware can be
+built like this:
+
+.. code:: shell
+
+    make PLAT=fvp DEBUG=1             \
+    ARM_LINUX_KERNEL_AS_BL33=1        \
+    PRELOADED_BL33_BASE=0x80080000    \
+    INITRD_SIZE=0x8000000             \
+    all fip
+
+Now the FVP binary can be run with the following command:
+
+.. code:: shell
+
+    <path-to>/FVP_Base_AEMv8A-AEMv8A                            \
+    -C bp.secureflashloader.fname=<path-to>/bl1.bin             \
+    -C bp.flashloader0.fname=<path-to>/fip.bin                  \
    --data cluster0.cpu0="<path-to>/<kernel-binary>"@0x80080000 \
-    --data cluster0.cpu0="<path-to>/<ramdisk.img>"@0x84000000
+    --data cluster0.cpu0="<path-to>/<initrd.bin>"@0x90000000
+
+Preloaded kernel image - Reset to BL31
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+We can also boot a Linux kernel by jumping directly to BL31 ``RESET_TO_BL31=1``.
+This requires preloading a DTB into memory. We can inject the initrd start and
+end properties into the DTB (HW_CONFIG) at build time which is then stored by
+TF-A in ``build/fvp/<build-type>/fdts/`` directory.
+
+For example, we can build the firmware as:
+
+.. code:: shell
+
+    make PLAT=fvp DEBUG=1                   \
+    RESET_TO_BL31=1                         \
+    ARM_LINUX_KERNEL_AS_BL33=1              \
+    PRELOADED_BL33_BASE=0x80080000          \
+    ARM_PRELOADED_DTB_BASE=0x87F00000       \
+    INITRD_BASE=0x88000000                  \
+    INITRD_PATH=<path-to>/initrd.bin
+
+Now we can run the binary as:
+
+.. code:: shell
+
+    <path-to>/FVP_Base_AEMv8A-AEMv8A                               \
+    -C cluster0.NUM_CORES=4                                        \
+    -C cluster0.cpu0.RVBAR=0x04001000                              \
+    -C cluster0.cpu1.RVBAR=0x04001000                              \
+    -C cluster0.cpu2.RVBAR=0x04001000                              \
+    -C cluster0.cpu3.RVBAR=0x04001000                              \
+    --data cluster0.cpu0="<path-to>/bl31.bin"@0x04001000           \
+    --data cluster0.cpu0="<path-to>/<kernel-binary>"@0x80080000    \
+    --data cluster0.cpu0="<path-to>/<initrd.bin>"@0x88000000       \
+    --data cluster0.cpu0="<path-to>/fdts/fvp-base-gicv3-psci.dtb"@87F00000

 Obtaining the Flattened Device Trees
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
--- a/make_helpers/build_macros.mk
+++ b/make_helpers/build_macros.mk
@ -604,6 +604,7 @@ $(DPRE): $(2) | $$$$(@D)/
 $(DOBJ): $(DPRE) $(filter-out %.d,$(MAKEFILE_LIST)) | $$$$(@D)/
 	$$(s)echo "  DTC     $$<"
 	$$(q)$($(ARCH)-dtc) $$(DTC_FLAGS) -d $(DTBDEP) -o $$@ $$<
+	$$($$@-after)

 -include $(DTBDEP)
 -include $(DTSDEP)
--- a/plat/arm/board/fvp/platform.mk
+++ b/plat/arm/board/fvp/platform.mk
@ -367,6 +367,19 @@ FVP_HW_CONFIG_DTS	:=	fdts/${FVP_DT_PREFIX}.dts

 FDT_SOURCES		+=	${FVP_HW_CONFIG_DTS}
 $(eval FVP_HW_CONFIG	:=	${BUILD_PLAT}/$(patsubst %.dts,%.dtb,$(FVP_HW_CONFIG_DTS)))
+HW_CONFIG		:=	${FVP_HW_CONFIG}
+
+# Set default initrd base 128MiB offset of the default kernel address in FVP
+INITRD_BASE		?=	0x90000000
+
+# Kernel base address supports Linux kernels before v5.7
+# DTB base 1MiB before normal base kernel address in FVP (0x88000000)
+ifeq (${ARM_LINUX_KERNEL_AS_BL33},1)
+    PRELOADED_BL33_BASE ?= 0x80080000
+    ifeq (${RESET_TO_BL31},1)
+        ARM_PRELOADED_DTB_BASE ?= 0x87F00000
+    endif
+endif

 ifeq (${TRANSFER_LIST}, 0)
 FDT_SOURCES		+=	$(addprefix plat/arm/board/fvp/fdts/,	\
@ -419,7 +432,6 @@ ifeq (${TRANSFER_LIST}, 1)
 include lib/transfer_list/transfer_list.mk

 ifeq ($(RESET_TO_BL31), 1)
-HW_CONFIG			:=	${FVP_HW_CONFIG}
 FW_HANDOFF_SIZE			:=	20000

 TRANSFER_LIST_DTB_OFFSET	:=	0x20
--- a/plat/arm/common/arm_common.mk
+++ b/plat/arm/common/arm_common.mk
@ -108,9 +108,6 @@ ifeq (${ARM_LINUX_KERNEL_AS_BL33},1)
      $(error ARM_LINUX_KERNEL_AS_BL33 is only available if RESET_TO_SP_MIN=1.)
    endif
  endif
-  ifndef PRELOADED_BL33_BASE
-    $(error PRELOADED_BL33_BASE must be set if ARM_LINUX_KERNEL_AS_BL33 is used.)
-  endif
  ifeq (${RESET_TO_BL31},1)
    ifndef ARM_PRELOADED_DTB_BASE
      $(error ARM_PRELOADED_DTB_BASE must be set if ARM_LINUX_KERNEL_AS_BL33 is used with RESET_TO_BL31.)