Re: [PATCH 23/31] nds32: Device tree support
From: Arnd Bergmann <arnd@arndb.de>
Date: 2017-11-08 09:53:33
Also in:
linux-arch, lkml
On Wed, Nov 8, 2017 at 6:55 AM, Greentime Hu [off-list ref] wrote:
quoted hunk ↗ jump to hunk
From: Greentime Hu <redacted> Signed-off-by: Vincent Chen <redacted> Signed-off-by: Greentime Hu <redacted> --- arch/nds32/boot/dts/Makefile | 8 ++++++ arch/nds32/boot/dts/ae3xx.dts | 55 ++++++++++++++++++++++++++++++++++++ arch/nds32/boot/dts/ag101p.dts | 60 ++++++++++++++++++++++++++++++++++++++++ arch/nds32/kernel/devtree.c | 45 ++++++++++++++++++++++++++++++ 4 files changed, 168 insertions(+) create mode 100644 arch/nds32/boot/dts/Makefile create mode 100644 arch/nds32/boot/dts/ae3xx.dts create mode 100644 arch/nds32/boot/dts/ag101p.dts create mode 100644 arch/nds32/kernel/devtree.cdiff --git a/arch/nds32/boot/dts/Makefile b/arch/nds32/boot/dts/Makefile new file mode 100644 index 0000000..d31faa8 --- /dev/null +++ b/arch/nds32/boot/dts/Makefile@@ -0,0 +1,8 @@ +ifneq '$(CONFIG_NDS32_BUILTIN_DTB)' '""' +BUILTIN_DTB := $(patsubst "%",%,$(CONFIG_NDS32_BUILTIN_DTB)).dtb.o +else +BUILTIN_DTB := +endif +obj-$(CONFIG_OF) += $(BUILTIN_DTB)
For new architectures, I think it's better to not support built-in dtb but instead require the boot loader to be aware of device trees.
quoted hunk ↗ jump to hunk
+clean-files := *.dtb *.dtb.Sdiff --git a/arch/nds32/boot/dts/ae3xx.dts b/arch/nds32/boot/dts/ae3xx.dts new file mode 100644 index 0000000..b6c85dc --- /dev/null +++ b/arch/nds32/boot/dts/ae3xx.dts@@ -0,0 +1,55 @@ +/dts-v1/; +/ { + compatible = "nds32 ae3xx";
ae3xx looks like a wildcard name for multiple boards. Please always have compatible names without wildcards. You usually also want to list both the SoC and the board here.
+ #address-cells = <1>;
+ #size-cells = <1>;
+ interrupt-parent = <&intc>;
+
+ chosen {
+ bootargs = "console=ttyS0,38400n8 earlyprintk=uart8250-32bit,0xf0300000 debug loglevel=7";
+ };Remove the earlyprintk option from the bootargs here, regular boards should never rely on earlyprintk. The "earlycon" support in the uart drivers works almost as well (it starts slightly later in the boot process), and it will pick up the uart from the chosen/stdout-path property.
+ if (!params || !early_init_dt_scan(params)) {
+ pr_crit("\n"
+ "Error: invalid device tree blob at (virtual address 0x%p)\n"
+ "The dtb must be 8-byte aligned and must not exceed 8 KB in size\n"
+ "\nPlease check your bootloader.", params);
What is the 8KB limit for the dtb for? This sounds really limiting
once you get to
more complex SoCs.
Arnd