openwrt/target/linux/generic/backport-5.15/733-v6.3-19-net-ethernet-mtk_eth_soc-set-MDIO-bus-clock-frequenc.patch
Daniel Golle 5b972d7272 generic: mtk_eth_soc: allow setting MDIO clock frequency
Backport patch allowing to set the MDIO bus clock frequency.
By default the MDIO bus clock runs on 2.5 MHz, allow increasing it
up to 25 MHz.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
2023-03-27 19:07:54 +01:00

77 lines
2.5 KiB
Diff

From c0a440031d4314d1023c1b87f43a4233634eebdb Mon Sep 17 00:00:00 2001
From: Daniel Golle <daniel@makrotopia.org>
Date: Sun, 19 Mar 2023 12:57:15 +0000
Subject: [PATCH] net: ethernet: mtk_eth_soc: set MDIO bus clock frequency
MIME-Version: 1.0
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Set MDIO bus clock frequency and allow setting a custom maximum
frequency from device tree.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
drivers/net/ethernet/mediatek/mtk_eth_soc.c | 21 +++++++++++++++++++++
drivers/net/ethernet/mediatek/mtk_eth_soc.h | 7 +++++++
2 files changed, 28 insertions(+)
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -704,8 +704,10 @@ static const struct phylink_mac_ops mtk_
static int mtk_mdio_init(struct mtk_eth *eth)
{
+ unsigned int max_clk = 2500000, divider;
struct device_node *mii_np;
int ret;
+ u32 val;
mii_np = of_get_child_by_name(eth->dev->of_node, "mdio-bus");
if (!mii_np) {
@@ -731,6 +733,25 @@ static int mtk_mdio_init(struct mtk_eth
eth->mii_bus->parent = eth->dev;
snprintf(eth->mii_bus->id, MII_BUS_ID_SIZE, "%pOFn", mii_np);
+
+ if (!of_property_read_u32(mii_np, "clock-frequency", &val)) {
+ if (val > MDC_MAX_FREQ || val < MDC_MAX_FREQ / MDC_MAX_DIVIDER) {
+ dev_err(eth->dev, "MDIO clock frequency out of range");
+ ret = -EINVAL;
+ goto err_put_node;
+ }
+ max_clk = val;
+ }
+ divider = min_t(unsigned int, DIV_ROUND_UP(MDC_MAX_FREQ, max_clk), 63);
+
+ /* Configure MDC Divider */
+ val = mtk_r32(eth, MTK_PPSC);
+ val &= ~PPSC_MDC_CFG;
+ val |= FIELD_PREP(PPSC_MDC_CFG, divider) | PPSC_MDC_TURBO;
+ mtk_w32(eth, val, MTK_PPSC);
+
+ dev_dbg(eth->dev, "MDC is running on %d Hz\n", MDC_MAX_FREQ / divider);
+
ret = of_mdiobus_register(eth->mii_bus, mii_np);
err_put_node:
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
@@ -363,6 +363,13 @@
#define RX_DMA_VTAG_V2 BIT(0)
#define RX_DMA_L4_VALID_V2 BIT(2)
+/* PHY Polling and SMI Master Control registers */
+#define MTK_PPSC 0x10000
+#define PPSC_MDC_CFG GENMASK(29, 24)
+#define PPSC_MDC_TURBO BIT(20)
+#define MDC_MAX_FREQ 25000000
+#define MDC_MAX_DIVIDER 63
+
/* PHY Indirect Access Control registers */
#define MTK_PHY_IAC 0x10004
#define PHY_IAC_ACCESS BIT(31)