[RFT net-next v3 1/5] net: stmmac: dwmac-meson8b: only configure the clocks in RGMII mode
From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Date: 2017-12-28 22:21:47
Also in:
linux-amlogic
Subsystem:
networking drivers, stmmac ethernet driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Neither the m25_div_clk nor the m250_div_clk or m250_mux_clk are used in
RMII mode. The m25_div_clk output is routed to the RGMII PHY's "RGMII
clock".
This means that we don't need to configure the clocks in RMII mode. The
driver however did this - with no effect since the clocks are not routed
to the PHY in RMII mode.
While here also rename meson8b_init_clk to meson8b_init_rgmii_clk to
make it easier to understand the code.
Fixes: 566e8251625304 ("net: stmmac: add a glue driver for the Amlogic Meson 8b / GXBB DWMAC")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
.../net/ethernet/stmicro/stmmac/dwmac-meson8b.c | 46 ++++++++++------------
1 file changed, 21 insertions(+), 25 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c
index 4404650b32c5..e1d5907e481c 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c@@ -81,7 +81,7 @@ static void meson8b_dwmac_mask_bits(struct meson8b_dwmac *dwmac, u32 reg, writel(data, dwmac->regs + reg); } -static int meson8b_init_clk(struct meson8b_dwmac *dwmac) +static int meson8b_init_rgmii_clk(struct meson8b_dwmac *dwmac) { struct clk_init_data init; int i, ret;
@@ -176,7 +176,6 @@ static int meson8b_init_clk(struct meson8b_dwmac *dwmac) static int meson8b_init_prg_eth(struct meson8b_dwmac *dwmac) { int ret; - unsigned long clk_rate; u8 tx_dly_val = 0; switch (dwmac->phy_mode) {
@@ -191,9 +190,6 @@ static int meson8b_init_prg_eth(struct meson8b_dwmac *dwmac) case PHY_INTERFACE_MODE_RGMII_ID: case PHY_INTERFACE_MODE_RGMII_TXID: - /* Generate a 25MHz clock for the PHY */ - clk_rate = 25 * 1000 * 1000; - /* enable RGMII mode */ meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_RGMII_MODE, PRG_ETH0_RGMII_MODE);
@@ -204,12 +200,24 @@ static int meson8b_init_prg_eth(struct meson8b_dwmac *dwmac) meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TXDLY_MASK, tx_dly_val << PRG_ETH0_TXDLY_SHIFT); + + ret = clk_prepare_enable(dwmac->m25_div_clk); + if (ret) { + dev_err(&dwmac->pdev->dev, "failed to enable the PHY clock\n"); + return ret; + } + + /* Generate the 25MHz RGMII clock for the PHY */ + ret = clk_set_rate(dwmac->m25_div_clk, 25 * 1000 * 1000); + if (ret) { + clk_disable_unprepare(dwmac->m25_div_clk); + + dev_err(&dwmac->pdev->dev, "failed to set PHY clock\n"); + return ret; + } break; case PHY_INTERFACE_MODE_RMII: - /* Use the rate of the mux clock for the internal RMII PHY */ - clk_rate = clk_get_rate(dwmac->m250_mux_clk); - /* disable RGMII mode -> enables RMII mode */ meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_RGMII_MODE, 0);
@@ -231,20 +239,6 @@ static int meson8b_init_prg_eth(struct meson8b_dwmac *dwmac) return -EINVAL; } - ret = clk_prepare_enable(dwmac->m25_div_clk); - if (ret) { - dev_err(&dwmac->pdev->dev, "failed to enable the PHY clock\n"); - return ret; - } - - ret = clk_set_rate(dwmac->m25_div_clk, clk_rate); - if (ret) { - clk_disable_unprepare(dwmac->m25_div_clk); - - dev_err(&dwmac->pdev->dev, "failed to set PHY clock\n"); - return ret; - } - /* enable TX_CLK and PHY_REF_CLK generator */ meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TX_AND_PHY_REF_CLK, PRG_ETH0_TX_AND_PHY_REF_CLK);
@@ -294,7 +288,7 @@ static int meson8b_dwmac_probe(struct platform_device *pdev) &dwmac->tx_delay_ns)) dwmac->tx_delay_ns = 2; - ret = meson8b_init_clk(dwmac); + ret = meson8b_init_rgmii_clk(dwmac); if (ret) goto err_remove_config_dt;
@@ -311,7 +305,8 @@ static int meson8b_dwmac_probe(struct platform_device *pdev) return 0; err_clk_disable: - clk_disable_unprepare(dwmac->m25_div_clk); + if (phy_interface_mode_is_rgmii(dwmac->phy_mode)) + clk_disable_unprepare(dwmac->m25_div_clk); err_remove_config_dt: stmmac_remove_config_dt(pdev, plat_dat);
@@ -322,7 +317,8 @@ static int meson8b_dwmac_remove(struct platform_device *pdev) { struct meson8b_dwmac *dwmac = get_stmmac_bsp_priv(&pdev->dev); - clk_disable_unprepare(dwmac->m25_div_clk); + if (phy_interface_mode_is_rgmii(dwmac->phy_mode)) + clk_disable_unprepare(dwmac->m25_div_clk); return stmmac_pltfr_remove(pdev); }
--
2.15.1