On Wed, 2020-10-14 at 17:02 -0500, Rob Herring wrote:

On Wed, Oct 14, 2020 at 2:12 PM Nicolas Saenz Julienne
[off-list ref] wrote:

quoted

Introduce of_dma_get_max_cpu_address(), which provides the highest CPU
physical address addressable by all DMA masters in the system. It's
specially useful for setting memory zones sizes at early boot time.

Signed-off-by: Nicolas Saenz Julienne <redacted>

---

[...]

quoted

+       struct of_range_parser parser;
+       phys_addr_t subtree_max_addr;
+       struct device_node *child;
+       phys_addr_t cpu_end = 0;
+       struct of_range range;
+       const __be32 *ranges;
+       int len;
+
+       if (!np)
+               np = of_root;
+
+       ranges = of_get_property(np, "dma-ranges", &len);

I'm not really following why you changed the algorithm here. You're
skipping disabled nodes which is good. Was there some other reason?

Yes, it's a little more complex. But I had to change it in order to be able to
start parsing down from an arbitrary device node, which is needed for the unit
tests.

for_each_of_allnodes() and friends will traverse the whole tree, regardless of
the starting point. I couldn't find a similar function that would just iterate
over a subsection of the tree, so I went with this recursive approach.

Regards,
Nicolas