From 58e1af972f4f8855561ec018e7a9c565d53c4639 Mon Sep 17 00:00:00 2001 From: Dario Binacchi Date: Wed, 30 Dec 2020 00:06:36 +0100 Subject: [PATCH] clk: ti: add gate clock driver The patch adds support for TI gate clock binding. The code is based on the drivers/clk/ti/gate.c driver of the Linux kernel version 5.9-rc7. For DT binding details see: - Documentation/devicetree/bindings/clock/ti/gate.txt Signed-off-by: Dario Binacchi --- drivers/clk/ti/Kconfig | 6 +++ drivers/clk/ti/Makefile | 1 + drivers/clk/ti/clk-gate.c | 93 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 100 insertions(+) create mode 100644 drivers/clk/ti/clk-gate.c diff --git a/drivers/clk/ti/Kconfig b/drivers/clk/ti/Kconfig index 87eea86c6f..30959a316a 100644 --- a/drivers/clk/ti/Kconfig +++ b/drivers/clk/ti/Kconfig @@ -16,6 +16,12 @@ config CLK_TI_DIVIDER help This enables the divider clock driver support on TI's SoCs. +config CLK_TI_GATE + bool "TI gate clock driver" + depends on CLK && OF_CONTROL + help + This enables the gate clock driver support on TI's SoCs. + config CLK_TI_MUX bool "TI mux clock driver" depends on CLK && OF_CONTROL && CLK_CCF diff --git a/drivers/clk/ti/Makefile b/drivers/clk/ti/Makefile index fd7094cff0..f8aa735c83 100644 --- a/drivers/clk/ti/Makefile +++ b/drivers/clk/ti/Makefile @@ -7,4 +7,5 @@ obj-$(CONFIG_ARCH_OMAP2PLUS) += clk.o obj-$(CONFIG_CLK_TI_AM3_DPLL) += clk-am3-dpll.o clk-am3-dpll-x2.o obj-$(CONFIG_CLK_TI_DIVIDER) += clk-divider.o +obj-$(CONFIG_CLK_TI_GATE) += clk-gate.o obj-$(CONFIG_CLK_TI_MUX) += clk-mux.o diff --git a/drivers/clk/ti/clk-gate.c b/drivers/clk/ti/clk-gate.c new file mode 100644 index 0000000000..236eaed6df --- /dev/null +++ b/drivers/clk/ti/clk-gate.c @@ -0,0 +1,93 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * TI gate clock support + * + * Copyright (C) 2020 Dario Binacchi + * + * Loosely based on Linux kernel drivers/clk/ti/gate.c + */ + +#include +#include +#include +#include +#include +#include + +struct clk_ti_gate_priv { + fdt_addr_t reg; + u8 enable_bit; + u32 flags; + bool invert_enable; +}; + +static int clk_ti_gate_disable(struct clk *clk) +{ + struct clk_ti_gate_priv *priv = dev_get_priv(clk->dev); + u32 v; + + v = readl(priv->reg); + if (priv->invert_enable) + v |= (1 << priv->enable_bit); + else + v &= ~(1 << priv->enable_bit); + + writel(v, priv->reg); + /* No OCP barrier needed here since it is a disable operation */ + return 0; +} + +static int clk_ti_gate_enable(struct clk *clk) +{ + struct clk_ti_gate_priv *priv = dev_get_priv(clk->dev); + u32 v; + + v = readl(priv->reg); + if (priv->invert_enable) + v &= ~(1 << priv->enable_bit); + else + v |= (1 << priv->enable_bit); + + writel(v, priv->reg); + /* OCP barrier */ + v = readl(priv->reg); + return 0; +} + +static int clk_ti_gate_of_to_plat(struct udevice *dev) +{ + struct clk_ti_gate_priv *priv = dev_get_priv(dev); + + priv->reg = dev_read_addr(dev); + if (priv->reg == FDT_ADDR_T_NONE) { + dev_err(dev, "failed to get control register\n"); + return -EINVAL; + } + + dev_dbg(dev, "reg=0x%08lx\n", priv->reg); + priv->enable_bit = dev_read_u32_default(dev, "ti,bit-shift", 0); + if (dev_read_bool(dev, "ti,set-rate-parent")) + priv->flags |= CLK_SET_RATE_PARENT; + + priv->invert_enable = dev_read_bool(dev, "ti,set-bit-to-disable"); + return 0; +} + +static struct clk_ops clk_ti_gate_ops = { + .enable = clk_ti_gate_enable, + .disable = clk_ti_gate_disable, +}; + +static const struct udevice_id clk_ti_gate_of_match[] = { + { .compatible = "ti,gate-clock" }, + { }, +}; + +U_BOOT_DRIVER(clk_ti_gate) = { + .name = "ti_gate_clock", + .id = UCLASS_CLK, + .of_match = clk_ti_gate_of_match, + .ofdata_to_platdata = clk_ti_gate_of_to_plat, + .priv_auto = sizeof(struct clk_ti_gate_priv), + .ops = &clk_ti_gate_ops, +}; -- 2.39.5