[PATCH net-next v5 07/14] net: macb: add mpfs specific usrio configuration

Conor Dooley conor at kernel.org
Wed Mar 25 09:28:11 PDT 2026


From: Conor Dooley <conor.dooley at microchip.com>

On mpfs the driver needs to make sure the tsu clock source is not the
fabric, as this requires that the hardware is in Timer Adjust mode,
which is not compatible with the linux driver trying to control the
hardware. It is unlikely that this will be set, as the peripheral is
reset during probe, but if the resets are not provided in devicetree
it's probable that this bit is set incorrectly, as U-Boot's macb driver
has the same issue with using usrio settings for at91 platforms as the
default.

Fixes: 8aad66aa59be5 ("net: macb: add polarfire soc reset support")
Signed-off-by: Conor Dooley <conor.dooley at microchip.com>
---
 drivers/net/ethernet/cadence/macb.h      |  2 ++
 drivers/net/ethernet/cadence/macb_main.c | 12 ++++++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index 1bdbe66b05590..8e5305f9a7545 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -788,6 +788,7 @@
 #define MACB_CAPS_EEE				BIT(25)
 #define MACB_CAPS_USRIO_HAS_MII			BIT(26)
 #define MACB_CAPS_USRIO_HAS_REFCLK_SOURCE	BIT(27)
+#define MACB_CAPS_USRIO_HAS_TSUCLK_SOURCE	BIT(28)
 
 /* LSO settings */
 #define MACB_LSO_UFO_ENABLE			0x01
@@ -1229,6 +1230,7 @@ struct macb_usrio_config {
 	u32 refclk;
 	u32 clken;
 	u32 hdfctlen;
+	u32 tsu_source;
 	bool refclk_default_external;
 };
 
diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index a1f8a6d9554fb..4e5967e6ffbe5 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -4921,6 +4921,9 @@ static int macb_init_dflt(struct platform_device *pdev)
 				val |= bp->usrio->refclk;
 		}
 
+		if (bp->caps & MACB_CAPS_USRIO_HAS_TSUCLK_SOURCE)
+			val |= bp->usrio->tsu_source;
+
 		macb_or_gem_writel(bp, USRIO, val);
 	}
 
@@ -5524,6 +5527,10 @@ static const struct macb_usrio_config at91_default_usrio = {
 	.clken = MACB_BIT(CLKEN),
 };
 
+static const struct macb_usrio_config mpfs_usrio = {
+	.tsu_source = 0,
+};
+
 static const struct macb_usrio_config sama7g5_gem_usrio = {
 	.mii = 0,
 	.rmii = 1,
@@ -5637,10 +5644,11 @@ static const struct macb_config zynq_config = {
 static const struct macb_config mpfs_config = {
 	.caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE |
 		MACB_CAPS_JUMBO |
-		MACB_CAPS_GEM_HAS_PTP,
+		MACB_CAPS_GEM_HAS_PTP |
+		MACB_CAPS_USRIO_HAS_TSUCLK_SOURCE,
 	.dma_burst_length = 16,
 	.init = init_reset_optional,
-	.usrio = &at91_default_usrio,
+	.usrio = &mpfs_usrio,
 	.max_tx_length = 4040, /* Cadence Erratum 1686 */
 	.jumbo_max_len = 4040,
 };
-- 
2.53.0




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