[RESEND PATCH v3] serial: ns16550: Enable clocks during probe

Samuel Holland samuel at sholland.org
Tue Oct 31 06:06:09 CET 2023


If the UART bus or baud clock has a gate, it must be enabled before the
UART can be used.

Reviewed-by: Stefan Roese <sr at denx.de>
Signed-off-by: Samuel Holland <samuel at sholland.org>
---

Changes in v3:
 - Switch back to the original patch, now that the phycore-rk3288 build
   is fixed by enabling LTO.

Changes in v2:
 - Only enable the first clock, as using the clk_get_bulk() API pushes
   a board (phycore-rk3288) over its SPL size limit.

 drivers/serial/ns16550.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
index 6deb1d8ddc5..a206d00919c 100644
--- a/drivers/serial/ns16550.c
+++ b/drivers/serial/ns16550.c
@@ -514,6 +514,7 @@ int ns16550_serial_probe(struct udevice *dev)
 	struct ns16550_plat *plat = dev_get_plat(dev);
 	struct ns16550 *const com_port = dev_get_priv(dev);
 	struct reset_ctl_bulk reset_bulk;
+	struct clk_bulk clk_bulk;
 	fdt_addr_t addr;
 	fdt_addr_t size;
 	int ret;
@@ -533,6 +534,10 @@ int ns16550_serial_probe(struct udevice *dev)
 	if (!ret)
 		reset_deassert_bulk(&reset_bulk);
 
+	ret = clk_get_bulk(dev, &clk_bulk);
+	if (!ret)
+		clk_enable_bulk(&clk_bulk);
+
 	com_port->plat = dev_get_plat(dev);
 	ns16550_init(com_port, -1);
 
-- 
2.41.0



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