[PATCH v2 2/7] linux-yocto: Enable risc-v TUNE_FEATURES ISA selections ** DO NOT MERGE **

Mark Hatle
2025-06-17T23:39:57Z

*** THIS NEEDS TO BE RE-IMPLEMENTED AS KERNEL-CACHE/KMETA ***

Allow the risc-v TUNE_FEATURES to select specific ISA (kconfig) selections
in the kernel config via config fragments.

This allows the following items to be selected dynamically:

CONFIG_ARCH_RV32I
CONFIG_ARCH_RV64I
CONFIG_FPU
CONFIG_RISCV_ISA_C
CONFIG_RISCV_ISA_V
CONFIG_RISCV_ISA_ZBB
CONFIG_RISCV_ISA_ZICBOM
CONFIG_RISCV_ISA_ZICBOZ
CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI

Signed-off-by: Mark Hatle <mark.hatle@amd.com>
---
meta/recipes-kernel/linux/files/risc-v-isa-c.cfg | 1 +
.../linux/files/risc-v-isa-clear.cfg | 9 +++++++++
meta/recipes-kernel/linux/files/risc-v-isa-fpu.cfg | 1 +
.../linux/files/risc-v-isa-rv32i.cfg | 2 ++
.../linux/files/risc-v-isa-rv64i.cfg | 2 ++
meta/recipes-kernel/linux/files/risc-v-isa-v.cfg | 1 +
meta/recipes-kernel/linux/files/risc-v-isa-zbb.cfg | 1 +
.../linux/files/risc-v-isa-zicbom.cfg | 1 +
meta/recipes-kernel/linux/linux-yocto.inc | 14 ++++++++++++++
9 files changed, 32 insertions(+)
create mode 100644 meta/recipes-kernel/linux/files/risc-v-isa-c.cfg
create mode 100644 meta/recipes-kernel/linux/files/risc-v-isa-clear.cfg
create mode 100644 meta/recipes-kernel/linux/files/risc-v-isa-fpu.cfg
create mode 100644 meta/recipes-kernel/linux/files/risc-v-isa-rv32i.cfg
create mode 100644 meta/recipes-kernel/linux/files/risc-v-isa-rv64i.cfg
create mode 100644 meta/recipes-kernel/linux/files/risc-v-isa-v.cfg
create mode 100644 meta/recipes-kernel/linux/files/risc-v-isa-zbb.cfg
create mode 100644 meta/recipes-kernel/linux/files/risc-v-isa-zicbom.cfg

diff --git a/meta/recipes-kernel/linux/files/risc-v-isa-c.cfg b/meta/recipes-kernel/linux/files/risc-v-isa-c.cfg
new file mode 100644
index 0000000000..1cb459f636
--- /dev/null
+++ b/meta/recipes-kernel/linux/files/risc-v-isa-c.cfg
@@ -0,0 +1 @@
+CONFIG_RISCV_ISA_C=y
diff --git a/meta/recipes-kernel/linux/files/risc-v-isa-clear.cfg b/meta/recipes-kernel/linux/files/risc-v-isa-clear.cfg
new file mode 100644
index 0000000000..ba18d7b9b5
--- /dev/null
+++ b/meta/recipes-kernel/linux/files/risc-v-isa-clear.cfg
@@ -0,0 +1,9 @@
+# CONFIG_ARCH_RV32I is not set
+# CONFIG_ARCH_RV64I is not set
+# CONFIG_FPU is not set
+# CONFIG_RISCV_ISA_C is not set
+# CONFIG_RISCV_ISA_V is not set
+# CONFIG_RISCV_ISA_ZBB is not set
+# CONFIG_RISCV_ISA_ZICBOM is not set
+# CONFIG_RISCV_ISA_ZICBOZ is not set
+# CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI is not set
diff --git a/meta/recipes-kernel/linux/files/risc-v-isa-fpu.cfg b/meta/recipes-kernel/linux/files/risc-v-isa-fpu.cfg
new file mode 100644
index 0000000000..c099c8e81d
--- /dev/null
+++ b/meta/recipes-kernel/linux/files/risc-v-isa-fpu.cfg
@@ -0,0 +1 @@
+CONFIG_FPU=y
diff --git a/meta/recipes-kernel/linux/files/risc-v-isa-rv32i.cfg b/meta/recipes-kernel/linux/files/risc-v-isa-rv32i.cfg
new file mode 100644
index 0000000000..4c6bac5138
--- /dev/null
+++ b/meta/recipes-kernel/linux/files/risc-v-isa-rv32i.cfg
@@ -0,0 +1,2 @@
+CONFIG_ARCH_RV32I=y
+CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI=y
diff --git a/meta/recipes-kernel/linux/files/risc-v-isa-rv64i.cfg b/meta/recipes-kernel/linux/files/risc-v-isa-rv64i.cfg
new file mode 100644
index 0000000000..002b492e4c
--- /dev/null
+++ b/meta/recipes-kernel/linux/files/risc-v-isa-rv64i.cfg
@@ -0,0 +1,2 @@
+CONFIG_ARCH_RV64I=y
+CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI=y
diff --git a/meta/recipes-kernel/linux/files/risc-v-isa-v.cfg b/meta/recipes-kernel/linux/files/risc-v-isa-v.cfg
new file mode 100644
index 0000000000..c29c97fc4a
--- /dev/null
+++ b/meta/recipes-kernel/linux/files/risc-v-isa-v.cfg
@@ -0,0 +1 @@
+CONFIG_RISCV_ISA_V=y
diff --git a/meta/recipes-kernel/linux/files/risc-v-isa-zbb.cfg b/meta/recipes-kernel/linux/files/risc-v-isa-zbb.cfg
new file mode 100644
index 0000000000..2b71b016f8
--- /dev/null
+++ b/meta/recipes-kernel/linux/files/risc-v-isa-zbb.cfg
@@ -0,0 +1 @@
+CONFIG_RISCV_ISA_ZBB=y
diff --git a/meta/recipes-kernel/linux/files/risc-v-isa-zicbom.cfg b/meta/recipes-kernel/linux/files/risc-v-isa-zicbom.cfg
new file mode 100644
index 0000000000..96daf04b20
--- /dev/null
+++ b/meta/recipes-kernel/linux/files/risc-v-isa-zicbom.cfg
@@ -0,0 +1 @@
+CONFIG_RISCV_ISA_ZICBOM=y
diff --git a/meta/recipes-kernel/linux/linux-yocto.inc b/meta/recipes-kernel/linux/linux-yocto.inc
index 389329030d..cdf2583698 100644
--- a/meta/recipes-kernel/linux/linux-yocto.inc
+++ b/meta/recipes-kernel/linux/linux-yocto.inc
@@ -37,6 +37,20 @@ KERNEL_FEATURES:append = " ${@bb.utils.contains('MACHINE_FEATURES', 'efi', 'cfg/
KERNEL_FEATURES:append = " ${@bb.utils.contains('MACHINE_FEATURES', 'numa', 'features/numa/numa.scc', '', d)}"
KERNEL_FEATURES:append = " ${@bb.utils.contains('MACHINE_FEATURES', 'vfat', 'cfg/fs/vfat.scc', '', d)}"

+SRC_URI_RISCV = "\
+ file://risc-v-isa-clear.cfg \
+ ${@bb.utils.contains( "TUNE_FEATURES", "rv 32 i m a", "file://risc-v-isa-rv32i.cfg", "", d)} \
+ ${@bb.utils.contains( "TUNE_FEATURES", "rv 64 i m a", "file://risc-v-isa-rv64i.cfg", "", d)} \
+ ${@bb.utils.contains( "TUNE_FEATURES", "f d", "file://risc-v-isa-fpu.cfg", "", d)} \
+ ${@bb.utils.contains( "TUNE_FEATURES", "c", "file://risc-v-isa-c.cfg", "", d)} \
+ ${@bb.utils.contains( "TUNE_FEATURES", "v", "file://risc-v-isa-v.cfg", "", d)} \
+ ${@bb.utils.contains_any("TUNE_FEATURES", "b zbb", "file://risc-v-isa-zbb.cfg", "", d)} \
+ ${@bb.utils.contains( "TUNE_FEATURES", "zicbom", "file://risc-v-isa-zicbom.cfg", "", d)} \
+ "
+
+SRC_URI:append:riscv32 = "${SRC_URI_RISCV}"
+SRC_URI:append:riscv64 = "${SRC_URI_RISCV}"
+
# A KMACHINE is the mapping of a yocto $MACHINE to what is built
# by the kernel. This is typically the branch that should be built,
# and it can be specific to the machine or shared
--
2.34.1