[PATCH v1 1/4] board: verdin-am62: improve comment on usb phy core voltage

Max Krummenacher max.oss.09 at gmail.com
Wed Jan 17 11:16:46 CET 2024


From: Max Krummenacher <max.krummenacher at toradex.com>

TI recommends to clear the bit independent of the used voltage.
So the comment which claims to do it due to the core voltage
at 0.85V is bogus.

See https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1252724/am625-usb-phy-core-voltage-selection-and-vdda_core_usb-mismatch

Signed-off-by: Max Krummenacher <max.krummenacher at toradex.com>
---

 board/toradex/verdin-am62/verdin-am62.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/board/toradex/verdin-am62/verdin-am62.c b/board/toradex/verdin-am62/verdin-am62.c
index d09dda5bccc..4e912b5f32f 100644
--- a/board/toradex/verdin-am62/verdin-am62.c
+++ b/board/toradex/verdin-am62/verdin-am62.c
@@ -101,12 +101,13 @@ void spl_board_init(void)
 {
 	u32 val;
 
-	/* Set USB0 PHY core voltage to 0.85V */
+	/* Clear USB0_PHY_CTRL_CORE_VOLTAGE */
+	/* TI recommends to clear the bit independent of VDDA_CORE_USB */
 	val = readl(CTRLMMR_USB0_PHY_CTRL);
 	val &= ~(CORE_VOLTAGE);
 	writel(val, CTRLMMR_USB0_PHY_CTRL);
 
-	/* Set USB1 PHY core voltage to 0.85V */
+	/* Clear USB1_PHY_CTRL_CORE_VOLTAGE */
 	val = readl(CTRLMMR_USB1_PHY_CTRL);
 	val &= ~(CORE_VOLTAGE);
 	writel(val, CTRLMMR_USB1_PHY_CTRL);
-- 
2.42.0



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