On 23-01-17 07:14:35, Oleksij Rempel wrote:
> Almost(?) every i'MX variant has clk mux for ethernet (rgmii/rmii) reference
i.MX
> clock located in the GPR1 register. So far this clk is configured in
> different ways:
> - mach-imx6q is doing mux configuration based on ptp vs enet_ref clk
> comparison.
> - mach-imx7d is setting mux to PAD for all boards
> - mach-imx6ul is setting mux to internal clock for all boards.
>
> Since we have imx7d and imx6ul board variants which do not work with
> configurations forced by kernel mach code, we need to implement this clk
> mux properly as part of the clk framework. Which is done by this patch.
>
> Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
Reviewed-by: Abel Vesa <abel.vesa@xxxxxxxxxx>
> ---
> drivers/clk/imx/Makefile | 1 +
> drivers/clk/imx/clk-gpr-mux.c | 119 ++++++++++++++++++++++++++++++++++
> drivers/clk/imx/clk.h | 5 ++
> 3 files changed, 125 insertions(+)
> create mode 100644 drivers/clk/imx/clk-gpr-mux.c
>
> diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile
> index e8aacb0ee6ac..a75d59f7cb8a 100644
> --- a/drivers/clk/imx/Makefile
> +++ b/drivers/clk/imx/Makefile
> @@ -22,6 +22,7 @@ mxc-clk-objs += clk-pllv3.o
> mxc-clk-objs += clk-pllv4.o
> mxc-clk-objs += clk-pll14xx.o
> mxc-clk-objs += clk-sscg-pll.o
> +mxc-clk-objs += clk-gpr-mux.o
> obj-$(CONFIG_MXC_CLK) += mxc-clk.o
>
> obj-$(CONFIG_CLK_IMX8MM) += clk-imx8mm.o
> diff --git a/drivers/clk/imx/clk-gpr-mux.c b/drivers/clk/imx/clk-gpr-mux.c
> new file mode 100644
> index 000000000000..47a3e3cdcc82
> --- /dev/null
> +++ b/drivers/clk/imx/clk-gpr-mux.c
> @@ -0,0 +1,119 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + */
> +
> +#define pr_fmt(fmt) "imx:clk-gpr-mux: " fmt
> +
> +#include <linux/module.h>
> +
> +#include <linux/clk-provider.h>
> +#include <linux/errno.h>
> +#include <linux/export.h>
> +#include <linux/io.h>
> +#include <linux/slab.h>
> +#include <linux/regmap.h>
> +#include <linux/mfd/syscon.h>
> +
> +#include "clk.h"
> +
> +struct imx_clk_gpr {
> + struct clk_hw hw;
> + struct regmap *regmap;
> + u32 mask;
> + u32 reg;
> + const u32 *mux_table;
> +};
> +
> +static struct imx_clk_gpr *to_imx_clk_gpr(struct clk_hw *hw)
> +{
> + return container_of(hw, struct imx_clk_gpr, hw);
> +}
> +
> +static u8 imx_clk_gpr_mux_get_parent(struct clk_hw *hw)
> +{
> + struct imx_clk_gpr *priv = to_imx_clk_gpr(hw);
> + unsigned int val;
> + int ret;
> +
> + ret = regmap_read(priv->regmap, priv->reg, &val);
> + if (ret)
> + goto get_parent_err;
> +
> + val &= priv->mask;
> +
> + ret = clk_mux_val_to_index(hw, priv->mux_table, 0, val);
> + if (ret < 0)
> + goto get_parent_err;
> +
> + return ret;
> +
> +get_parent_err:
> + pr_err("failed to get parent (%pe)\n", ERR_PTR(ret));
> +
> + /* return some realistic non negative value. Potentially we could
> + * give index to some dummy error parent.
> + */
> + return 0;
> +}
> +
> +static int imx_clk_gpr_mux_set_parent(struct clk_hw *hw, u8 index)
> +{
> + struct imx_clk_gpr *priv = to_imx_clk_gpr(hw);
> + unsigned int val = clk_mux_index_to_val(priv->mux_table, 0, index);
> +
> + return regmap_update_bits(priv->regmap, priv->reg, priv->mask, val);
> +}
> +
> +static int imx_clk_gpr_mux_determine_rate(struct clk_hw *hw,
> + struct clk_rate_request *req)
> +{
> + return clk_mux_determine_rate_flags(hw, req, 0);
> +}
> +
> +const struct clk_ops imx_clk_gpr_mux_ops = {
> + .get_parent = imx_clk_gpr_mux_get_parent,
> + .set_parent = imx_clk_gpr_mux_set_parent,
> + .determine_rate = imx_clk_gpr_mux_determine_rate,
> +};
> +
> +struct clk_hw *imx_clk_gpr_mux(const char *name, const char *compatible,
> + u32 reg, const char **parent_names,
> + u8 num_parents, const u32 *mux_table, u32 mask)
> +{
> + struct clk_init_data init = { };
> + struct imx_clk_gpr *priv;
> + struct regmap *regmap;
> + struct clk_hw *hw;
> + int ret;
> +
> + regmap = syscon_regmap_lookup_by_compatible(compatible);
> + if (IS_ERR(regmap)) {
> + pr_err("failed to find %s regmap\n", compatible);
> + return ERR_CAST(regmap);
> + }
> +
> + priv = kzalloc(sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return ERR_PTR(-ENOMEM);
> +
> + init.name = name;
> + init.ops = &imx_clk_gpr_mux_ops;
> + init.parent_names = parent_names;
> + init.num_parents = num_parents;
> + init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
> +
> + priv->hw.init = &init;
> + priv->regmap = regmap;
> + priv->mux_table = mux_table;
> + priv->reg = reg;
> + priv->mask = mask;
> +
> + hw = &priv->hw;
> + ret = clk_hw_register(NULL, &priv->hw);
> + if (ret) {
> + kfree(priv);
> + hw = ERR_PTR(ret);
> + }
> +
> + return hw;
> +}
> diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h
> index 689b3ad927c0..801213109697 100644
> --- a/drivers/clk/imx/clk.h
> +++ b/drivers/clk/imx/clk.h
> @@ -458,4 +458,9 @@ struct clk_hw *imx_clk_hw_divider_gate(const char *name, const char *parent_name
> unsigned long flags, void __iomem *reg, u8 shift, u8 width,
> u8 clk_divider_flags, const struct clk_div_table *table,
> spinlock_t *lock);
> +
> +struct clk_hw *imx_clk_gpr_mux(const char *name, const char *compatible,
> + u32 reg, const char **parent_names,
> + u8 num_parents, const u32 *mux_table, u32 mask);
> +
> #endif
> --
> 2.30.2
>
