1 From c0a440031d4314d1023c1b87f43a4233634eebdb Mon Sep 17 00:00:00 2001
2 From: Daniel Golle <daniel@makrotopia.org>
3 Date: Sun, 19 Mar 2023 12:57:15 +0000
4 Subject: [PATCH] net: ethernet: mtk_eth_soc: set MDIO bus clock frequency
6 Content-Type: text/plain; charset=UTF-8
7 Content-Transfer-Encoding: 8bit
9 Set MDIO bus clock frequency and allow setting a custom maximum
10 frequency from device tree.
12 Reviewed-by: Andrew Lunn <andrew@lunn.ch>
13 Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
14 Tested-by: Bjørn Mork <bjorn@mork.no>
15 Signed-off-by: Daniel Golle <daniel@makrotopia.org>
16 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
18 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 21 +++++++++++++++++++++
19 drivers/net/ethernet/mediatek/mtk_eth_soc.h | 7 +++++++
20 2 files changed, 28 insertions(+)
22 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
23 +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
24 @@ -704,8 +704,10 @@ static const struct phylink_mac_ops mtk_
26 static int mtk_mdio_init(struct mtk_eth *eth)
28 + unsigned int max_clk = 2500000, divider;
29 struct device_node *mii_np;
33 mii_np = of_get_child_by_name(eth->dev->of_node, "mdio-bus");
35 @@ -731,6 +733,25 @@ static int mtk_mdio_init(struct mtk_eth
36 eth->mii_bus->parent = eth->dev;
38 snprintf(eth->mii_bus->id, MII_BUS_ID_SIZE, "%pOFn", mii_np);
40 + if (!of_property_read_u32(mii_np, "clock-frequency", &val)) {
41 + if (val > MDC_MAX_FREQ || val < MDC_MAX_FREQ / MDC_MAX_DIVIDER) {
42 + dev_err(eth->dev, "MDIO clock frequency out of range");
48 + divider = min_t(unsigned int, DIV_ROUND_UP(MDC_MAX_FREQ, max_clk), 63);
50 + /* Configure MDC Divider */
51 + val = mtk_r32(eth, MTK_PPSC);
52 + val &= ~PPSC_MDC_CFG;
53 + val |= FIELD_PREP(PPSC_MDC_CFG, divider) | PPSC_MDC_TURBO;
54 + mtk_w32(eth, val, MTK_PPSC);
56 + dev_dbg(eth->dev, "MDC is running on %d Hz\n", MDC_MAX_FREQ / divider);
58 ret = of_mdiobus_register(eth->mii_bus, mii_np);
61 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h
62 +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h
64 #define RX_DMA_VTAG_V2 BIT(0)
65 #define RX_DMA_L4_VALID_V2 BIT(2)
67 +/* PHY Polling and SMI Master Control registers */
68 +#define MTK_PPSC 0x10000
69 +#define PPSC_MDC_CFG GENMASK(29, 24)
70 +#define PPSC_MDC_TURBO BIT(20)
71 +#define MDC_MAX_FREQ 25000000
72 +#define MDC_MAX_DIVIDER 63
74 /* PHY Indirect Access Control registers */
75 #define MTK_PHY_IAC 0x10004
76 #define PHY_IAC_ACCESS BIT(31)