[U-Boot] [PATCH] pci: pci_mvebu: Add comment about missing of_n_addr_cells() call

[Stefan Roese]

This patch adds a comment to explain the use of the hardcoded value for
the number of address cells in mvebu_get_tgt_attr(). This should help to
rework this function, once CONFIG_OF_LIVE is enabled for MVEBU in
general.

Signed-off-by: Stefan Roese <sr at denx.de>
Cc: Bin Meng <bmeng.cn at gmail.com>
---
 drivers/pci/pci_mvebu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/pci/pci_mvebu.c b/drivers/pci/pci_mvebu.c
index 6026fa67f9..e21dc10c2f 100644
--- a/drivers/pci/pci_mvebu.c
+++ b/drivers/pci/pci_mvebu.c
@@ -369,6 +369,12 @@ static int mvebu_get_tgt_attr(ofnode node, int devfn,
 	if (!range)
 		return -EINVAL;
 
+	/*
+	 * Linux uses of_n_addr_cells() to get the number of address cells
+	 * here. Currently this function is only available in U-Boot when
+	 * CONFIG_OF_LIVE is enabled. Until this is enabled for MVEBU in
+	 * general, lets't hardcode the "pna" value in the U-Boot code.
+	 */
 	pna = 2; /* hardcoded for now because of lack of of_n_addr_cells() */
 	rangesz = pna + na + ns;
 	nranges = rlen / sizeof(__be32) / rangesz;
-- 
2.20.1