diff options
| author | Frederik Haxel <haxel@fzi.de> | 2023-12-12 14:01:14 +0100 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-01-10 04:33:22 +0100 |
| commit | 6c4a2f6329f0925161a80d2fd90aa8438c1ca82f (patch) | |
| tree | 2aa0af7da64cdf39792aaafd2c39790013278729 /arch/riscv/kernel | |
| parent | riscv: Fixed wrong register in XIP_FIXUP_FLASH_OFFSET macro (diff) | |
| download | linux-6c4a2f6329f0925161a80d2fd90aa8438c1ca82f.tar.xz linux-6c4a2f6329f0925161a80d2fd90aa8438c1ca82f.zip | |
riscv: Allow disabling of BUILTIN_DTB for XIP
This enables, among other things, testing with the QEMU virt machine.
To build an XIP kernel for the QEMU virt machine, configure the
the kernel as desired and apply the following configuration
```
CONFIG_NONPORTABLE=y
CONFIG_XIP_KERNEL=y
CONFIG_XIP_PHYS_ADDR=0x20000000
CONFIG_PHYS_RAM_BASE=0x80200000
CONFIG_BUILTIN_DTB=n
```
Since the QEMU virt flash memory expects a 32 MB file, the built image
must be padded. For example, with
`truncate -s 32M arch/riscv/boot/xipImage`
The kernel can be started using the following command in QEMU (v8+)
```
qemu-system-riscv64 -M virt,pflash0=pflash0 \
-blockdev node-name=pflash0,driver=file,read-only=on,\
filename=arch/riscv/boot/xipImage <optional parameters>
```
Signed-off-by: Frederik Haxel <haxel@fzi.de>
Link: https://lore.kernel.org/r/20231212130116.848530-4-haxel@fzi.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/kernel')
| -rw-r--r-- | arch/riscv/kernel/head.S | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index a2e2f0dd3899..a8939558702c 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -266,10 +266,12 @@ SYM_CODE_START(_start_kernel) la sp, _end + THREAD_SIZE XIP_FIXUP_OFFSET sp mv s0, a0 + mv s1, a1 call __copy_data - /* Restore a0 copy */ + /* Restore a0 & a1 copy */ mv a0, s0 + mv a1, s1 #endif #ifndef CONFIG_XIP_KERNEL |