| Message ID | 20170908071156.5115-11-clabbe.montjoie@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
> +#define DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID 0 > +#define DWMAC_sUN8I_MDIO_MUX_EXTERNAL_ID 1 > > /* H3/A64 specific bits */ > #define SYSCON_RMII_EN BIT(13) /* 1: enable RMII (overrides EPIT) */ > @@ -634,6 +639,76 @@ static int sun8i_dwmac_reset(struct stmmac_priv *priv) > return 0; > } > > +/* MDIO multiplexing switch function > + * This function is called by the mdio-mux layer when it thinks the mdio bus > + * multiplexer needs to switch. > + * 'current_child' is the current value of the mux register > + * 'desired_child' is the value of the 'reg' property of the target child MDIO > + * node. > + * The first time this function is called, current_child == -1. > + * If current_child == desired_child, then the mux is already set to the > + * correct bus. > + * > + * Note that we do not use reg/mask like mdio-mux-mmioreg because we need to > + * know easily which bus is used (reset must be done only for desired bus). > + */ > +static int mdio_mux_syscon_switch_fn(int current_child, int desired_child, > + void *data) > +{ > + struct stmmac_priv *priv = data; > + struct sunxi_priv_data *gmac = priv->plat->bsp_priv; > + u32 reg, val; > + int ret = 0; > + bool need_reset = false; > + > + if (current_child ^ desired_child) { > + regmap_read(gmac->regmap, SYSCON_EMAC_REG, ®); > + switch (desired_child) { > + case DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID: > + dev_info(priv->device, "Switch mux to internal PHY"); > + val = (reg & ~H3_EPHY_MUX_MASK) | H3_EPHY_SELECT; > + if (gmac->use_internal_phy) > + need_reset = true; > + break; This i don't get. Why do you need use_internal_phy? Isn't that implicit from DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID? Is it even possible to use an external PHY on the internal MDIO bus? > + case DWMAC_sUN8I_MDIO_MUX_EXTERNAL_ID: > + dev_info(priv->device, "Switch mux to external PHY"); > + val = (reg & ~H3_EPHY_MUX_MASK) | H3_EPHY_SHUTDOWN; > + if (!gmac->use_internal_phy) > + need_reset = true; > + break; And is it possible to use the internal PHY on the external bus? Andrew
On Fri, Sep 08, 2017 at 03:05:20PM +0200, Andrew Lunn wrote: > > +#define DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID 0 > > +#define DWMAC_sUN8I_MDIO_MUX_EXTERNAL_ID 1 > > > > /* H3/A64 specific bits */ > > #define SYSCON_RMII_EN BIT(13) /* 1: enable RMII (overrides EPIT) */ > > @@ -634,6 +639,76 @@ static int sun8i_dwmac_reset(struct stmmac_priv *priv) > > return 0; > > } > > > > +/* MDIO multiplexing switch function > > + * This function is called by the mdio-mux layer when it thinks the mdio bus > > + * multiplexer needs to switch. > > + * 'current_child' is the current value of the mux register > > + * 'desired_child' is the value of the 'reg' property of the target child MDIO > > + * node. > > + * The first time this function is called, current_child == -1. > > + * If current_child == desired_child, then the mux is already set to the > > + * correct bus. > > + * > > + * Note that we do not use reg/mask like mdio-mux-mmioreg because we need to > > + * know easily which bus is used (reset must be done only for desired bus). > > + */ > > +static int mdio_mux_syscon_switch_fn(int current_child, int desired_child, > > + void *data) > > +{ > > + struct stmmac_priv *priv = data; > > + struct sunxi_priv_data *gmac = priv->plat->bsp_priv; > > + u32 reg, val; > > + int ret = 0; > > + bool need_reset = false; > > + > > + if (current_child ^ desired_child) { > > + regmap_read(gmac->regmap, SYSCON_EMAC_REG, ®); > > + switch (desired_child) { > > + case DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID: > > + dev_info(priv->device, "Switch mux to internal PHY"); > > + val = (reg & ~H3_EPHY_MUX_MASK) | H3_EPHY_SELECT; > > + if (gmac->use_internal_phy) > > + need_reset = true; > > + break; > > This i don't get. Why do you need use_internal_phy? Isn't that > implicit from DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID? Is it even possible to > use an external PHY on the internal MDIO bus? > On my H3 box with external PHY, the MDIO mux library first select (for scan ?) the internal MDIO. Without use_internal_phy usage, this board will launch a reset to use the internal MDIO... and this reset timeout/fail. After the MDIO mux select the external MDIO. > > + case DWMAC_sUN8I_MDIO_MUX_EXTERNAL_ID: > > + dev_info(priv->device, "Switch mux to external PHY"); > > + val = (reg & ~H3_EPHY_MUX_MASK) | H3_EPHY_SHUTDOWN; > > + if (!gmac->use_internal_phy) > > + need_reset = true; > > + break; > > And is it possible to use the internal PHY on the external bus? > I need to check that. Regards
> > > +static int mdio_mux_syscon_switch_fn(int current_child, int desired_child, > > > + void *data) > > > +{ > > > + struct stmmac_priv *priv = data; > > > + struct sunxi_priv_data *gmac = priv->plat->bsp_priv; > > > + u32 reg, val; > > > + int ret = 0; > > > + bool need_reset = false; > > > + > > > + if (current_child ^ desired_child) { > > > + regmap_read(gmac->regmap, SYSCON_EMAC_REG, ®); > > > + switch (desired_child) { > > > + case DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID: > > > + dev_info(priv->device, "Switch mux to internal PHY"); > > > + val = (reg & ~H3_EPHY_MUX_MASK) | H3_EPHY_SELECT; > > > + if (gmac->use_internal_phy) > > > + need_reset = true; > > > + break; > > > > This i don't get. Why do you need use_internal_phy? Isn't that > > implicit from DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID? Is it even possible to > > use an external PHY on the internal MDIO bus? > > > > On my H3 box with external PHY, the MDIO mux library first select (for scan ?) the internal MDIO. > Without use_internal_phy usage, this board will launch a reset to use the internal MDIO... and this reset timeout/fail. Do you know why the reset times out/fails? Andrew
On Fri, Sep 08, 2017 at 04:00:20PM +0200, Andrew Lunn wrote: > > > > +static int mdio_mux_syscon_switch_fn(int current_child, int desired_child, > > > > + void *data) > > > > +{ > > > > + struct stmmac_priv *priv = data; > > > > + struct sunxi_priv_data *gmac = priv->plat->bsp_priv; > > > > + u32 reg, val; > > > > + int ret = 0; > > > > + bool need_reset = false; > > > > + > > > > + if (current_child ^ desired_child) { > > > > + regmap_read(gmac->regmap, SYSCON_EMAC_REG, ®); > > > > + switch (desired_child) { > > > > + case DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID: > > > > + dev_info(priv->device, "Switch mux to internal PHY"); > > > > + val = (reg & ~H3_EPHY_MUX_MASK) | H3_EPHY_SELECT; > > > > + if (gmac->use_internal_phy) > > > > + need_reset = true; > > > > + break; > > > > > > This i don't get. Why do you need use_internal_phy? Isn't that > > > implicit from DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID? Is it even possible to > > > use an external PHY on the internal MDIO bus? > > > > > > > On my H3 box with external PHY, the MDIO mux library first select (for scan ?) the internal MDIO. > > Without use_internal_phy usage, this board will launch a reset to use the internal MDIO... and this reset timeout/fail. > > Do you know why the reset times out/fails? > Because there are nothing connected to it. I got also reset timeout on integrated MDIO when the integrated PHY is not powered.
> > Do you know why the reset times out/fails? > > > > Because there are nothing connected to it. That should not be an issue. A read should just return 0xffff. And it should return 0xffff fast. The timing of the MDIO protocol is fixed. A read or a write takes a fixed number of cycles, independent of if there is a device there or not. The bus data line has a pullup, so if you try to access a missing device, you automatically read 0xffff. Andrew
On Fri, Sep 08, 2017 at 04:17:36PM +0200, Andrew Lunn wrote: > > > Do you know why the reset times out/fails? > > > > > > > Because there are nothing connected to it. > > That should not be an issue. A read should just return 0xffff. And it > should return 0xffff fast. The timing of the MDIO protocol is fixed. A > read or a write takes a fixed number of cycles, independent of if > there is a device there or not. The bus data line has a pullup, so if > you try to access a missing device, you automatically read 0xffff. > Perhaps, but the reality is that with nothing connected to it, the reset of the MAC timeout. Certainly, the MAC does not support finding no PHY. So, to prevent an error message, and a "freeze" of the net process, the need_reset trick is necessary. Regards Corentin Labbe
On Fri, Sep 08, 2017 at 04:28:25PM +0200, Corentin Labbe wrote: > On Fri, Sep 08, 2017 at 04:17:36PM +0200, Andrew Lunn wrote: > > > > Do you know why the reset times out/fails? > > > > > > > > > > Because there are nothing connected to it. > > > > That should not be an issue. A read should just return 0xffff. And it > > should return 0xffff fast. The timing of the MDIO protocol is fixed. A > > read or a write takes a fixed number of cycles, independent of if > > there is a device there or not. The bus data line has a pullup, so if > > you try to access a missing device, you automatically read 0xffff. > > > > Perhaps, but the reality is that with nothing connected to it, the reset of the MAC timeout. > Certainly, the MAC does not support finding no PHY. Are you sure this is not because of the clock and reset? + #address-cells = <1>; + #size-cells = <0>; + int_mii_phy: ethernet-phy@1 { + compatible = "ethernet-phy-ieee802.3-c22"; + reg = <1>; + clocks = <&ccu CLK_BUS_EPHY>; + resets = <&ccu RST_BUS_EPHY>; The way you describe it here, the clock and reset are for the PHY. But maybe it is actually for the bus? I can understand a bus timing out if it has no clock, or it is held in reset. Try enabling the clock and reset when the internal bus is selected, not when the PHY on the bus is selected. Andrew
diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig index 97035766c291..e28c0d2c58e9 100644 --- a/drivers/net/ethernet/stmicro/stmmac/Kconfig +++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig @@ -159,6 +159,7 @@ config DWMAC_SUN8I tristate "Allwinner sun8i GMAC support" default ARCH_SUNXI depends on OF && (ARCH_SUNXI || COMPILE_TEST) + select MDIO_BUS_MUX ---help--- Support for Allwinner H3 A83T A64 EMAC ethernet controllers. diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c index 672553b652bd..ddd5695886ac 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c @@ -17,6 +17,7 @@ #include <linux/clk.h> #include <linux/io.h> #include <linux/iopoll.h> +#include <linux/mdio-mux.h> #include <linux/mfd/syscon.h> #include <linux/module.h> #include <linux/of_device.h> @@ -71,6 +72,7 @@ struct sunxi_priv_data { const struct emac_variant *variant; struct regmap *regmap; bool use_internal_phy; + void *mux_handle; }; static const struct emac_variant emac_variant_h3 = { @@ -195,6 +197,9 @@ static const struct emac_variant emac_variant_a64 = { #define H3_EPHY_LED_POL BIT(17) /* 1: active low, 0: active high */ #define H3_EPHY_SHUTDOWN BIT(16) /* 1: shutdown, 0: power up */ #define H3_EPHY_SELECT BIT(15) /* 1: internal PHY, 0: external PHY */ +#define H3_EPHY_MUX_MASK (H3_EPHY_SHUTDOWN | H3_EPHY_SELECT) +#define DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID 0 +#define DWMAC_sUN8I_MDIO_MUX_EXTERNAL_ID 1 /* H3/A64 specific bits */ #define SYSCON_RMII_EN BIT(13) /* 1: enable RMII (overrides EPIT) */ @@ -634,6 +639,76 @@ static int sun8i_dwmac_reset(struct stmmac_priv *priv) return 0; } +/* MDIO multiplexing switch function + * This function is called by the mdio-mux layer when it thinks the mdio bus + * multiplexer needs to switch. + * 'current_child' is the current value of the mux register + * 'desired_child' is the value of the 'reg' property of the target child MDIO + * node. + * The first time this function is called, current_child == -1. + * If current_child == desired_child, then the mux is already set to the + * correct bus. + * + * Note that we do not use reg/mask like mdio-mux-mmioreg because we need to + * know easily which bus is used (reset must be done only for desired bus). + */ +static int mdio_mux_syscon_switch_fn(int current_child, int desired_child, + void *data) +{ + struct stmmac_priv *priv = data; + struct sunxi_priv_data *gmac = priv->plat->bsp_priv; + u32 reg, val; + int ret = 0; + bool need_reset = false; + + if (current_child ^ desired_child) { + regmap_read(gmac->regmap, SYSCON_EMAC_REG, ®); + switch (desired_child) { + case DWMAC_sUN8I_MDIO_MUX_INTERNAL_ID: + dev_info(priv->device, "Switch mux to internal PHY"); + val = (reg & ~H3_EPHY_MUX_MASK) | H3_EPHY_SELECT; + if (gmac->use_internal_phy) + need_reset = true; + break; + case DWMAC_sUN8I_MDIO_MUX_EXTERNAL_ID: + dev_info(priv->device, "Switch mux to external PHY"); + val = (reg & ~H3_EPHY_MUX_MASK) | H3_EPHY_SHUTDOWN; + if (!gmac->use_internal_phy) + need_reset = true; + break; + default: + dev_err(priv->device, "Invalid child id %x\n", desired_child); + return -EINVAL; + } + regmap_write(gmac->regmap, SYSCON_EMAC_REG, val); + /* After changing syscon value, the MAC need reset or it will use + * the last value (and so the last PHY set). + * Reset is necessary only when we reach the needed MDIO, + * it timeout in other case. + */ + if (need_reset) + ret = sun8i_dwmac_reset(priv); + else + dev_dbg(priv->device, "skipped reset\n"); + } + return ret; +} + +static int sun8i_dwmac_register_mdio_mux(struct stmmac_priv *priv) +{ + int ret; + struct device_node *mdio_mux; + struct sunxi_priv_data *gmac = priv->plat->bsp_priv; + + mdio_mux = of_get_child_by_name(priv->device->of_node, "mdio-mux"); + if (!mdio_mux) + return -ENODEV; + + ret = mdio_mux_init(priv->device, mdio_mux, mdio_mux_syscon_switch_fn, + &gmac->mux_handle, priv, priv->mii); + return ret; +} + static int sun8i_dwmac_set_syscon(struct stmmac_priv *priv) { struct sunxi_priv_data *gmac = priv->plat->bsp_priv; @@ -649,12 +724,7 @@ static int sun8i_dwmac_set_syscon(struct stmmac_priv *priv) val, reg); if (gmac->variant->soc_has_internal_phy) { - if (!gmac->use_internal_phy) { - /* switch to external PHY interface */ - reg &= ~H3_EPHY_SELECT; - } else { - reg |= H3_EPHY_SELECT; - reg &= ~H3_EPHY_SHUTDOWN; + if (gmac->use_internal_phy) { dev_dbg(priv->device, "Select internal_phy %x\n", reg); if (of_property_read_bool(priv->plat->phy_node, @@ -743,6 +813,8 @@ static void sun8i_dwmac_unset_syscon(struct sunxi_priv_data *gmac) { u32 reg = gmac->variant->default_syscon_value; + if (gmac->variant->soc_has_internal_phy) + mdio_mux_uninit(gmac->mux_handle); regmap_write(gmac->regmap, SYSCON_EMAC_REG, reg); } @@ -801,12 +873,6 @@ static int sun8i_power_phy(struct stmmac_priv *priv) if (ret) return ret; - /* After changing syscon value, the MAC need reset or it will use - * the last value (and so the last PHY set. - */ - ret = sun8i_dwmac_reset(priv); - if (ret) - return ret; return 0; } @@ -889,6 +955,8 @@ static int sun8i_dwmac_probe(struct platform_device *pdev) struct sunxi_priv_data *gmac; struct device *dev = &pdev->dev; int ret; + struct stmmac_priv *priv; + struct net_device *ndev; ret = stmmac_get_platform_resources(pdev, &stmmac_res); if (ret) @@ -973,9 +1041,31 @@ static int sun8i_dwmac_probe(struct platform_device *pdev) ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res); if (ret) - sun8i_dwmac_exit(pdev, plat_dat->bsp_priv); + goto dwmac_exit; + + ndev = dev_get_drvdata(&pdev->dev); + priv = netdev_priv(ndev); + /* The mux must be registered after parent MDIO + * so after stmmac_dvr_probe() + */ + if (gmac->variant->soc_has_internal_phy) { + ret = sun8i_dwmac_register_mdio_mux(priv); + if (ret) { + dev_err(&pdev->dev, "Failed to register mux\n"); + goto dwmac_mux; + } + } else { + ret = sun8i_dwmac_reset(priv); + if (ret) + goto dwmac_exit; + } return ret; +dwmac_mux: + sun8i_dwmac_unset_syscon(gmac); +dwmac_exit: + sun8i_dwmac_exit(pdev, plat_dat->bsp_priv); +return ret; } static const struct of_device_id sun8i_dwmac_match[] = {
The Allwinner H3 SoC have two distinct MDIO bus, only one could be active at the same time. The selection of the active MDIO bus are done via some bits in the EMAC register of the system controller. This patch implement this MDIO switch via a custom MDIO-mux. Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com> --- drivers/net/ethernet/stmicro/stmmac/Kconfig | 1 + drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c | 116 +++++++++++++++++++--- 2 files changed, 104 insertions(+), 13 deletions(-)