[U-Boot] [RFC] fdt expert advice needed

Matthias Fuchs
2009-02-01T21:30:20Z

Hi Scott,

thanks for your hint. Please see my updated code below.
Do you think it's ok this way?

Matthias

---
cpu/ppc4xx/fdt.c | 24 ++++++++++++++++++++++--
1 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/cpu/ppc4xx/fdt.c b/cpu/ppc4xx/fdt.c
index c55e1cf..f9ff560 100644
--- a/cpu/ppc4xx/fdt.c
+++ b/cpu/ppc4xx/fdt.c
@@ -113,6 +113,7 @@ void fdt_pcie_setup(void *blob)
void ft_cpu_setup(void *blob, bd_t *bd)
{
sys_info_t sys_info;
+ int off, ndepth = 0;

get_sys_info(&sys_info);

@@ -133,9 +134,28 @@ void ft_cpu_setup(void *blob, bd_t *bd)
fdt_fixup_memory(blob, (u64)bd->bi_memstart, (u64)bd->bi_memsize);

/*
- * Setup all baudrates for the UARTs
+ * Setup all UART clocks for CPU internal UARTs
+ * (only these UARTs are definetely clocked by gd->uart_clk)
+ *
+ * These UARTs are direct childs of /plb/opb. This code
+ * does not touch any UARTs that are connected to the ebc.
*/
- do_fixup_by_compat_u32(blob, "ns16550", "clock-frequency", gd->uart_clk, 1);
+ off = fdt_path_offset(blob, "/plb/opb");
+ while ((off = fdt_next_node(blob, off, &ndepth)) >= 0) {
+ /*
+ * process all sub nodes and stop when we are back
+ * at the starting depth
+ */
+ if (ndepth == 0)
+ break;
+
+ /* only update direct childs */
+ if ((ndepth == 1) &&
+ (fdt_node_check_compatible(blob, off, "ns16550") == 0))
+ fdt_setprop(blob, off,
+ "clock-frequency",
+ (void*)&(gd->uart_clk), 4);
+ }

/*
* Fixup all ethernet nodes
--
1.5.6.3

> Scott Wood wrote:
> > Matthias Fuchs wrote:
> >> Now I want to replace the above code to only touch the ns16550 compatible nodes
> >> that are direct childs of /plb/opb. Not those under /plb/ebc and even not those under
> >> /plb/opb/ebc. This is not easy to do with the fdt API. Below you find my first and dirty
> >> hack.
> >>
> >> Isn't there a more simple way to do so? Don't bother me about the printf, variable names etc.
> >> It's just for discussion.
> >
> > Take the node that you want to search under (/plb/opb), and pass it to
> > fdt_next_node(), with an initial depth of zero. Continue until depth
> > returns to zero (or less).
>
> I just saw that you want to restrict it to direct children -- for that,
> ignore any nodes where depth != 1.
>
> -Scott