Add driver for BCM63268 timer clock and reset controller. Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx> --- drivers/clk/bcm/Kconfig | 9 ++ drivers/clk/bcm/Makefile | 1 + drivers/clk/bcm/clk-bcm63268-timer.c | 232 +++++++++++++++++++++++++++ 3 files changed, 242 insertions(+) create mode 100644 drivers/clk/bcm/clk-bcm63268-timer.c diff --git a/drivers/clk/bcm/Kconfig b/drivers/clk/bcm/Kconfig index ec738f74a026..952c3b6ff71a 100644 --- a/drivers/clk/bcm/Kconfig +++ b/drivers/clk/bcm/Kconfig @@ -37,6 +37,15 @@ config CLK_BCM_63XX_GATE Enable common clock framework support for Broadcom BCM63xx DSL SoCs based on the MIPS architecture +config CLK_BCM63268_TIMER + bool "Broadcom BCM63268 timer clock and reset support" + depends on BMIPS_GENERIC || COMPILE_TEST + default BMIPS_GENERIC + select RESET_CONTROLLER + help + Enable timer clock and reset support for Broadcom BCM63268 DSL SoCs + based on the MIPS architecture. + config CLK_BCM_KONA bool "Broadcom Kona CCU clock support" depends on ARCH_BCM_MOBILE || COMPILE_TEST diff --git a/drivers/clk/bcm/Makefile b/drivers/clk/bcm/Makefile index edb66b44cb27..d0b6f4b1fb08 100644 --- a/drivers/clk/bcm/Makefile +++ b/drivers/clk/bcm/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_CLK_BCM_63XX) += clk-bcm63xx.o obj-$(CONFIG_CLK_BCM_63XX_GATE) += clk-bcm63xx-gate.o +obj-$(CONFIG_CLK_BCM63268_TIMER) += clk-bcm63268-timer.o obj-$(CONFIG_CLK_BCM_KONA) += clk-kona.o obj-$(CONFIG_CLK_BCM_KONA) += clk-kona-setup.o obj-$(CONFIG_CLK_BCM_KONA) += clk-bcm281xx.o diff --git a/drivers/clk/bcm/clk-bcm63268-timer.c b/drivers/clk/bcm/clk-bcm63268-timer.c new file mode 100644 index 000000000000..5609c4ddb50c --- /dev/null +++ b/drivers/clk/bcm/clk-bcm63268-timer.c @@ -0,0 +1,232 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * BCM63268 Timer Clock and Reset Controller Driver + * + * Copyright (C) 2021 Álvaro Fernández Rojas <noltari@xxxxxxxxx> + */ + +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/reset-controller.h> + +#include <dt-bindings/clock/bcm63268-clock.h> + +#define BCM63268_TIMER_RESET_SLEEP_MIN_US 10000 +#define BCM63268_TIMER_RESET_SLEEP_MAX_US 20000 + +struct bcm63268_tclkrst_hw { + void __iomem *regs; + spinlock_t lock; + + struct reset_controller_dev rcdev; + struct clk_hw_onecell_data data; +}; + +struct bcm63268_tclk_table_entry { + const char * const name; + u8 bit; + unsigned long flags; +}; + +static const struct bcm63268_tclk_table_entry bcm63268_timer_clocks[] = { + { + .name = "ephy1", + .bit = BCM63268_TCLK_EPHY1, + }, { + .name = "ephy2", + .bit = BCM63268_TCLK_EPHY2, + }, { + .name = "ephy3", + .bit = BCM63268_TCLK_EPHY3, + }, { + .name = "gphy1", + .bit = BCM63268_TCLK_GPHY1, + }, { + .name = "dsl", + .bit = BCM63268_TCLK_DSL, + }, { + .name = "wakeon_ephy", + .bit = BCM63268_TCLK_WAKEON_EPHY, + }, { + .name = "wakeon_dsl", + .bit = BCM63268_TCLK_WAKEON_DSL, + }, { + .name = "fap1_pll", + .bit = BCM63268_TCLK_FAP1, + }, { + .name = "fap2_pll", + .bit = BCM63268_TCLK_FAP2, + }, { + .name = "uto_50", + .bit = BCM63268_TCLK_UTO_50, + }, { + .name = "uto_extin", + .bit = BCM63268_TCLK_UTO_EXTIN, + }, { + .name = "usb_ref", + .bit = BCM63268_TCLK_USB_REF, + }, { + /* sentinel */ + } +}; + +static inline struct bcm63268_tclkrst_hw * +to_bcm63268_timer_reset(struct reset_controller_dev *rcdev) +{ + return container_of(rcdev, struct bcm63268_tclkrst_hw, rcdev); +} + +static int bcm63268_timer_reset_update(struct reset_controller_dev *rcdev, + unsigned long id, bool assert) +{ + struct bcm63268_tclkrst_hw *reset = to_bcm63268_timer_reset(rcdev); + unsigned long flags; + uint32_t val; + + spin_lock_irqsave(&reset->lock, flags); + val = __raw_readl(reset->regs); + if (assert) + val &= ~BIT(id); + else + val |= BIT(id); + __raw_writel(val, reset->regs); + spin_unlock_irqrestore(&reset->lock, flags); + + return 0; +} + +static int bcm63268_timer_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return bcm63268_timer_reset_update(rcdev, id, true); +} + +static int bcm63268_timer_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return bcm63268_timer_reset_update(rcdev, id, false); +} + +static int bcm63268_timer_reset_reset(struct reset_controller_dev *rcdev, + unsigned long id) +{ + bcm63268_timer_reset_update(rcdev, id, true); + usleep_range(BCM63268_TIMER_RESET_SLEEP_MIN_US, + BCM63268_TIMER_RESET_SLEEP_MAX_US); + + bcm63268_timer_reset_update(rcdev, id, false); + /* + * Ensure component is taken out reset state by sleeping also after + * deasserting the reset. Otherwise, the component may not be ready + * for operation. + */ + usleep_range(BCM63268_TIMER_RESET_SLEEP_MIN_US, + BCM63268_TIMER_RESET_SLEEP_MAX_US); + + return 0; +} + +static int bcm63268_timer_reset_status(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct bcm63268_tclkrst_hw *reset = to_bcm63268_timer_reset(rcdev); + + return !(__raw_readl(reset->regs) & BIT(id)); +} + +static struct reset_control_ops bcm63268_timer_reset_ops = { + .assert = bcm63268_timer_reset_assert, + .deassert = bcm63268_timer_reset_deassert, + .reset = bcm63268_timer_reset_reset, + .status = bcm63268_timer_reset_status, +}; + +static int bcm63268_tclk_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct bcm63268_tclk_table_entry *entry, *table; + struct bcm63268_tclkrst_hw *hw; + u8 maxbit = 0; + int i, ret; + + table = of_device_get_match_data(dev); + if (!table) + return -EINVAL; + + for (entry = table; entry->name; entry++) + maxbit = max_t(u8, maxbit, entry->bit); + maxbit++; + + hw = devm_kzalloc(&pdev->dev, struct_size(hw, data.hws, maxbit), + GFP_KERNEL); + if (!hw) + return -ENOMEM; + + platform_set_drvdata(pdev, hw); + + spin_lock_init(&hw->lock); + + hw->data.num = maxbit; + for (i = 0; i < maxbit; i++) + hw->data.hws[i] = ERR_PTR(-ENODEV); + + hw->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(hw->regs)) + return PTR_ERR(hw->regs); + + for (entry = table; entry->name; entry++) { + struct clk_hw *clk; + + clk = clk_hw_register_gate(dev, entry->name, NULL, + entry->flags, hw->regs, entry->bit, + CLK_GATE_BIG_ENDIAN, &hw->lock); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + goto out_err; + } + + hw->data.hws[entry->bit] = clk; + } + + ret = of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get, + &hw->data); + if (!ret) + return 0; + + hw->rcdev.of_node = dev->of_node; + hw->rcdev.ops = &bcm63268_timer_reset_ops; + + ret = devm_reset_controller_register(dev, &hw->rcdev); + if (ret) + dev_err(dev, "Failed to register reset controller\n"); + +out_err: + for (i = 0; i < hw->data.num; i++) { + if (!IS_ERR(hw->data.hws[i])) + clk_hw_unregister_gate(hw->data.hws[i]); + } + + return ret; +} + +static const struct of_device_id bcm63268_tclk_dt_ids[] = { + { + .compatible = "brcm,bcm63268-timer-clocks", + .data = &bcm63268_timer_clocks, + }, { + /* sentinel */ + } +}; + +static struct platform_driver bcm63268_tclk = { + .probe = bcm63268_tclk_probe, + .driver = { + .name = "bcm63268-timer-clock", + .of_match_table = bcm63268_tclk_dt_ids, + }, +}; +builtin_platform_driver(bcm63268_tclk); -- 2.20.1