From 2f77296d3df9915490f41fc8a971cba00e0b4a2c Mon Sep 17 00:00:00 2001 From: Aisheng Dong Date: Thu, 13 Dec 2018 15:43:01 +0000 Subject: clk: imx: add lpcg clock support The Low-Power Clock Gate (LPCG) modules contain a local programming model to control the clock gates for the peripherals. An LPCG module is used to locally gate the clocks for the associated peripheral. And they're bedind the SCU clock. Cc: Stephen Boyd Cc: Shawn Guo Cc: Sascha Hauer Cc: Fabio Estevam Cc: Michael Turquette Signed-off-by: Dong Aisheng Signed-off-by: Stephen Boyd --- drivers/clk/imx/Makefile | 3 +- drivers/clk/imx/clk-lpcg-scu.c | 116 +++++++++++++++++++++++++++++++++++++++++ drivers/clk/imx/clk-scu.h | 3 ++ 3 files changed, 121 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/imx/clk-lpcg-scu.c (limited to 'drivers/clk') diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile index a8a4518b065b..8577f780ad31 100644 --- a/drivers/clk/imx/Makefile +++ b/drivers/clk/imx/Makefile @@ -14,7 +14,8 @@ obj-$(CONFIG_MXC_CLK) += \ clk-pfd.o obj-$(CONFIG_MXC_CLK_SCU) += \ - clk-scu.o + clk-scu.o \ + clk-lpcg-scu.o obj-$(CONFIG_CLK_IMX8QXP) += clk-imx8qxp.o diff --git a/drivers/clk/imx/clk-lpcg-scu.c b/drivers/clk/imx/clk-lpcg-scu.c new file mode 100644 index 000000000000..a73a799fb777 --- /dev/null +++ b/drivers/clk/imx/clk-lpcg-scu.c @@ -0,0 +1,116 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2018 NXP + * Dong Aisheng + */ + +#include +#include +#include +#include +#include + +#include "clk-scu.h" + +static DEFINE_SPINLOCK(imx_lpcg_scu_lock); + +#define CLK_GATE_SCU_LPCG_MASK 0x3 +#define CLK_GATE_SCU_LPCG_HW_SEL BIT(0) +#define CLK_GATE_SCU_LPCG_SW_SEL BIT(1) + +/* + * struct clk_lpcg_scu - Description of LPCG clock + * + * @hw: clk_hw of this LPCG + * @reg: register of this LPCG clock + * @bit_idx: bit index of this LPCG clock + * @hw_gate: HW auto gate enable + * + * This structure describes one LPCG clock + */ +struct clk_lpcg_scu { + struct clk_hw hw; + void __iomem *reg; + u8 bit_idx; + bool hw_gate; +}; + +#define to_clk_lpcg_scu(_hw) container_of(_hw, struct clk_lpcg_scu, hw) + +static int clk_lpcg_scu_enable(struct clk_hw *hw) +{ + struct clk_lpcg_scu *clk = to_clk_lpcg_scu(hw); + unsigned long flags; + u32 reg, val; + + spin_lock_irqsave(&imx_lpcg_scu_lock, flags); + + reg = readl_relaxed(clk->reg); + reg &= ~(CLK_GATE_SCU_LPCG_MASK << clk->bit_idx); + + val = CLK_GATE_SCU_LPCG_SW_SEL; + if (clk->hw_gate) + val |= CLK_GATE_SCU_LPCG_HW_SEL; + + reg |= val << clk->bit_idx; + writel(reg, clk->reg); + + spin_unlock_irqrestore(&imx_lpcg_scu_lock, flags); + + return 0; +} + +static void clk_lpcg_scu_disable(struct clk_hw *hw) +{ + struct clk_lpcg_scu *clk = to_clk_lpcg_scu(hw); + unsigned long flags; + u32 reg; + + spin_lock_irqsave(&imx_lpcg_scu_lock, flags); + + reg = readl_relaxed(clk->reg); + reg &= ~(CLK_GATE_SCU_LPCG_MASK << clk->bit_idx); + writel(reg, clk->reg); + + spin_unlock_irqrestore(&imx_lpcg_scu_lock, flags); +} + +static const struct clk_ops clk_lpcg_scu_ops = { + .enable = clk_lpcg_scu_enable, + .disable = clk_lpcg_scu_disable, +}; + +struct clk_hw *imx_clk_lpcg_scu(const char *name, const char *parent_name, + unsigned long flags, void __iomem *reg, + u8 bit_idx, bool hw_gate) +{ + struct clk_lpcg_scu *clk; + struct clk_init_data init; + struct clk_hw *hw; + int ret; + + clk = kzalloc(sizeof(*clk), GFP_KERNEL); + if (!clk) + return ERR_PTR(-ENOMEM); + + clk->reg = reg; + clk->bit_idx = bit_idx; + clk->hw_gate = hw_gate; + + init.name = name; + init.ops = &clk_lpcg_scu_ops; + init.flags = CLK_SET_RATE_PARENT | flags; + init.parent_names = parent_name ? &parent_name : NULL; + init.num_parents = parent_name ? 1 : 0; + + clk->hw.init = &init; + + hw = &clk->hw; + ret = clk_hw_register(NULL, hw); + if (ret) { + kfree(clk); + hw = ERR_PTR(ret); + } + + return hw; +} diff --git a/drivers/clk/imx/clk-scu.h b/drivers/clk/imx/clk-scu.h index 309b4de20b25..52c1746ec988 100644 --- a/drivers/clk/imx/clk-scu.h +++ b/drivers/clk/imx/clk-scu.h @@ -12,4 +12,7 @@ int imx_clk_scu_init(void); struct clk_hw *imx_clk_scu(const char *name, u32 rsrc_id, u8 clk_type); +struct clk_hw *imx_clk_lpcg_scu(const char *name, const char *parent_name, + unsigned long flags, void __iomem *reg, + u8 bit_idx, bool hw_gate); #endif -- cgit v1.2.3-59-g8ed1b