[PATCH net-next v5 03/14] net: macb: split USRIO_HAS_CLKEN capability in two

Conor Dooley
2026-03-25T16:29:08Z

While trying to rework the internal/external refclk selection on
sama7g5, Ryan and I noticed that the sama7g5 was "overloading" the
meaning of MACB_CAPS_USRIO_HAS_CLKEN, using it differently to how it was
originally intended.
Originally, on the macb hardware on sam9620 et al,
MACB_CAPS_USRIO_HAS_CLKEN represented the hardware having a bit that
needed to be set to turn on the input clock to the transceivers. The
sama7g5 doesn't have this bit, so for some reason the decision was made
to reuse this capability flag to control selection of internal/external
references.

Split the caps in two, so that capabilities do what they say on the tin,
and allow reworking the refclk selection handling without impacting the
older devices that use MACB_CAPS_USRIO_CLKEN for its original purpose.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
drivers/net/ethernet/cadence/macb.h | 2 ++
drivers/net/ethernet/cadence/macb_main.c | 11 ++++++++---
2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index 32217de5e0730..35b7129d7c1ee 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -787,6 +787,7 @@
#define MACB_CAPS_NO_LSO BIT(24)
#define MACB_CAPS_EEE BIT(25)
#define MACB_CAPS_USRIO_HAS_MII BIT(26)
+#define MACB_CAPS_USRIO_HAS_REFCLK_SOURCE BIT(27)

/* LSO settings */
#define MACB_LSO_UFO_ENABLE 0x01
@@ -1226,6 +1227,7 @@ struct macb_usrio_config {
u32 rmii;
u32 rgmii;
u32 refclk;
+ u32 clken;
u32 hdfctlen;
};

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 05a2df6e3e41d..859d03502666a 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -4615,7 +4615,7 @@ static void macb_configure_caps(struct macb *bp,
}

if (refclk_ext)
- bp->caps |= MACB_CAPS_USRIO_HAS_CLKEN;
+ bp->caps |= MACB_CAPS_USRIO_HAS_REFCLK_SOURCE;

dev_dbg(&bp->pdev->dev, "Cadence caps 0x%08x\n", bp->caps);
}
@@ -4895,6 +4895,9 @@ static int macb_init_dflt(struct platform_device *pdev)
}

if (bp->caps & MACB_CAPS_USRIO_HAS_CLKEN)
+ val |= bp->usrio->clken;
+
+ if (bp->caps & MACB_CAPS_USRIO_HAS_REFCLK_SOURCE)
val |= bp->usrio->refclk;

macb_or_gem_writel(bp, USRIO, val);
@@ -5497,7 +5500,7 @@ static const struct macb_usrio_config at91_default_usrio = {
.mii = MACB_BIT(MII),
.rmii = MACB_BIT(RMII),
.rgmii = GEM_BIT(RGMII),
- .refclk = MACB_BIT(CLKEN),
+ .clken = MACB_BIT(CLKEN),
};

static const struct macb_usrio_config sama7g5_usrio = {
@@ -5615,6 +5618,7 @@ static const struct macb_config mpfs_config = {
static const struct macb_config sama7g5_gem_config = {
.caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_CLK_HW_CHG |
MACB_CAPS_USRIO_DEFAULT_IS_MII_GMII |
+ MACB_CAPS_USRIO_HAS_REFCLK_SOURCE |
MACB_CAPS_MIIONRGMII | MACB_CAPS_GEM_HAS_PTP |
MACB_CAPS_USRIO_HAS_MII,
.dma_burst_length = 16,
@@ -5623,7 +5627,8 @@ static const struct macb_config sama7g5_gem_config = {

static const struct macb_config sama7g5_emac_config = {
.caps = MACB_CAPS_USRIO_DEFAULT_IS_MII_GMII |
- MACB_CAPS_USRIO_HAS_CLKEN | MACB_CAPS_MIIONRGMII |
+ MACB_CAPS_MIIONRGMII |
+ MACB_CAPS_USRIO_HAS_REFCLK_SOURCE |
MACB_CAPS_GEM_HAS_PTP |
MACB_CAPS_USRIO_HAS_MII,
.dma_burst_length = 16,
--
2.53.0