diff options
Diffstat (limited to 'drivers/clk/tegra/clk.c')
| -rw-r--r-- | drivers/clk/tegra/clk.c | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/drivers/clk/tegra/clk.c b/drivers/clk/tegra/clk.c new file mode 100644 index 0000000000..19037346f5 --- /dev/null +++ b/drivers/clk/tegra/clk.c @@ -0,0 +1,453 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + */ + +#include <linux/clkdev.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/clk/tegra.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/reset-controller.h> +#include <linux/string_helpers.h> + +#include <soc/tegra/fuse.h> + +#include "clk.h" + +/* Global data of Tegra CPU CAR ops */ +static struct device_node *tegra_car_np; +static struct tegra_cpu_car_ops dummy_car_ops; +struct tegra_cpu_car_ops *tegra_cpu_car_ops = &dummy_car_ops; + +int *periph_clk_enb_refcnt; +static int periph_banks; +static u32 *periph_state_ctx; +static struct clk **clks; +static int clk_num; +static struct clk_onecell_data clk_data; + +/* Handlers for SoC-specific reset lines */ +static int (*special_reset_assert)(unsigned long); +static int (*special_reset_deassert)(unsigned long); +static unsigned int num_special_reset; + +static const struct tegra_clk_periph_regs periph_regs[] = { + [0] = { + .enb_reg = CLK_OUT_ENB_L, + .enb_set_reg = CLK_OUT_ENB_SET_L, + .enb_clr_reg = CLK_OUT_ENB_CLR_L, + .rst_reg = RST_DEVICES_L, + .rst_set_reg = RST_DEVICES_SET_L, + .rst_clr_reg = RST_DEVICES_CLR_L, + }, + [1] = { + .enb_reg = CLK_OUT_ENB_H, + .enb_set_reg = CLK_OUT_ENB_SET_H, + .enb_clr_reg = CLK_OUT_ENB_CLR_H, + .rst_reg = RST_DEVICES_H, + .rst_set_reg = RST_DEVICES_SET_H, + .rst_clr_reg = RST_DEVICES_CLR_H, + }, + [2] = { + .enb_reg = CLK_OUT_ENB_U, + .enb_set_reg = CLK_OUT_ENB_SET_U, + .enb_clr_reg = CLK_OUT_ENB_CLR_U, + .rst_reg = RST_DEVICES_U, + .rst_set_reg = RST_DEVICES_SET_U, + .rst_clr_reg = RST_DEVICES_CLR_U, + }, + [3] = { + .enb_reg = CLK_OUT_ENB_V, + .enb_set_reg = CLK_OUT_ENB_SET_V, + .enb_clr_reg = CLK_OUT_ENB_CLR_V, + .rst_reg = RST_DEVICES_V, + .rst_set_reg = RST_DEVICES_SET_V, + .rst_clr_reg = RST_DEVICES_CLR_V, + }, + [4] = { + .enb_reg = CLK_OUT_ENB_W, + .enb_set_reg = CLK_OUT_ENB_SET_W, + .enb_clr_reg = CLK_OUT_ENB_CLR_W, + .rst_reg = RST_DEVICES_W, + .rst_set_reg = RST_DEVICES_SET_W, + .rst_clr_reg = RST_DEVICES_CLR_W, + }, + [5] = { + .enb_reg = CLK_OUT_ENB_X, + .enb_set_reg = CLK_OUT_ENB_SET_X, + .enb_clr_reg = CLK_OUT_ENB_CLR_X, + .rst_reg = RST_DEVICES_X, + .rst_set_reg = RST_DEVICES_SET_X, + .rst_clr_reg = RST_DEVICES_CLR_X, + }, + [6] = { + .enb_reg = CLK_OUT_ENB_Y, + .enb_set_reg = CLK_OUT_ENB_SET_Y, + .enb_clr_reg = CLK_OUT_ENB_CLR_Y, + .rst_reg = RST_DEVICES_Y, + .rst_set_reg = RST_DEVICES_SET_Y, + .rst_clr_reg = RST_DEVICES_CLR_Y, + }, +}; + +static void __iomem *clk_base; + +static int tegra_clk_rst_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + /* + * If peripheral is on the APB bus then we must read the APB bus to + * flush the write operation in apb bus. This will avoid peripheral + * access after disabling clock. Since the reset driver has no + * knowledge of which reset IDs represent which devices, simply do + * this all the time. + */ + tegra_read_chipid(); + + if (id < periph_banks * 32) { + writel_relaxed(BIT(id % 32), + clk_base + periph_regs[id / 32].rst_set_reg); + return 0; + } else if (id < periph_banks * 32 + num_special_reset) { + return special_reset_assert(id); + } + + return -EINVAL; +} + +static int tegra_clk_rst_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + if (id < periph_banks * 32) { + writel_relaxed(BIT(id % 32), + clk_base + periph_regs[id / 32].rst_clr_reg); + return 0; + } else if (id < periph_banks * 32 + num_special_reset) { + return special_reset_deassert(id); + } + + return -EINVAL; +} + +static int tegra_clk_rst_reset(struct reset_controller_dev *rcdev, + unsigned long id) +{ + int err; + + err = tegra_clk_rst_assert(rcdev, id); + if (err) + return err; + + udelay(1); + + return tegra_clk_rst_deassert(rcdev, id); +} + +const struct tegra_clk_periph_regs *get_reg_bank(int clkid) +{ + int reg_bank = clkid / 32; + + if (reg_bank < periph_banks) + return &periph_regs[reg_bank]; + else { + WARN_ON(1); + return NULL; + } +} + +void tegra_clk_set_pllp_out_cpu(bool enable) +{ + u32 val; + + val = readl_relaxed(clk_base + CLK_OUT_ENB_Y); + if (enable) + val |= CLK_ENB_PLLP_OUT_CPU; + else + val &= ~CLK_ENB_PLLP_OUT_CPU; + + writel_relaxed(val, clk_base + CLK_OUT_ENB_Y); +} + +void tegra_clk_periph_suspend(void) +{ + unsigned int i, idx; + + idx = 0; + for (i = 0; i < periph_banks; i++, idx++) + periph_state_ctx[idx] = + readl_relaxed(clk_base + periph_regs[i].enb_reg); + + for (i = 0; i < periph_banks; i++, idx++) + periph_state_ctx[idx] = + readl_relaxed(clk_base + periph_regs[i].rst_reg); +} + +void tegra_clk_periph_resume(void) +{ + unsigned int i, idx; + + idx = 0; + for (i = 0; i < periph_banks; i++, idx++) + writel_relaxed(periph_state_ctx[idx], + clk_base + periph_regs[i].enb_reg); + /* + * All non-boot peripherals will be in reset state on resume. + * Wait for 5us of reset propagation delay before de-asserting + * the peripherals based on the saved context. + */ + fence_udelay(5, clk_base); + + for (i = 0; i < periph_banks; i++, idx++) + writel_relaxed(periph_state_ctx[idx], + clk_base + periph_regs[i].rst_reg); + + fence_udelay(2, clk_base); +} + +static int tegra_clk_periph_ctx_init(int banks) +{ + periph_state_ctx = kcalloc(2 * banks, sizeof(*periph_state_ctx), + GFP_KERNEL); + if (!periph_state_ctx) + return -ENOMEM; + + return 0; +} + +struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks) +{ + clk_base = regs; + + if (WARN_ON(banks > ARRAY_SIZE(periph_regs))) + return NULL; + + periph_clk_enb_refcnt = kcalloc(32 * banks, + sizeof(*periph_clk_enb_refcnt), + GFP_KERNEL); + if (!periph_clk_enb_refcnt) + return NULL; + + periph_banks = banks; + + clks = kcalloc(num, sizeof(struct clk *), GFP_KERNEL); + if (!clks) { + kfree(periph_clk_enb_refcnt); + return NULL; + } + + clk_num = num; + + if (IS_ENABLED(CONFIG_PM_SLEEP)) { + if (tegra_clk_periph_ctx_init(banks)) { + kfree(periph_clk_enb_refcnt); + kfree(clks); + return NULL; + } + } + + return clks; +} + +void __init tegra_init_dup_clks(struct tegra_clk_duplicate *dup_list, + struct clk *clks[], int clk_max) +{ + struct clk *clk; + + for (; dup_list->clk_id < clk_max; dup_list++) { + clk = clks[dup_list->clk_id]; + dup_list->lookup.clk = clk; + clkdev_add(&dup_list->lookup); + } +} + +void tegra_init_from_table(struct tegra_clk_init_table *tbl, + struct clk *clks[], int clk_max) +{ + struct clk *clk; + + for (; tbl->clk_id < clk_max; tbl++) { + clk = clks[tbl->clk_id]; + if (IS_ERR_OR_NULL(clk)) { + pr_err("%s: invalid entry %ld in clks array for id %d\n", + __func__, PTR_ERR(clk), tbl->clk_id); + WARN_ON(1); + + continue; + } + + if (tbl->parent_id < clk_max) { + struct clk *parent = clks[tbl->parent_id]; + if (clk_set_parent(clk, parent)) { + pr_err("%s: Failed to set parent %s of %s\n", + __func__, __clk_get_name(parent), + __clk_get_name(clk)); + WARN_ON(1); + } + } + + if (tbl->rate) + if (clk_set_rate(clk, tbl->rate)) { + pr_err("%s: Failed to set rate %lu of %s\n", + __func__, tbl->rate, + __clk_get_name(clk)); + WARN_ON(1); + } + + if (tbl->state) + if (clk_prepare_enable(clk)) { + pr_err("%s: Failed to enable %s\n", __func__, + __clk_get_name(clk)); + WARN_ON(1); + } + } +} + +static const struct reset_control_ops rst_ops = { + .assert = tegra_clk_rst_assert, + .deassert = tegra_clk_rst_deassert, + .reset = tegra_clk_rst_reset, +}; + +static struct reset_controller_dev rst_ctlr = { + .ops = &rst_ops, + .owner = THIS_MODULE, + .of_reset_n_cells = 1, +}; + +void __init tegra_add_of_provider(struct device_node *np, + void *clk_src_onecell_get) +{ + int i; + + tegra_car_np = np; + + for (i = 0; i < clk_num; i++) { + if (IS_ERR(clks[i])) { + pr_err + ("Tegra clk %d: register failed with %ld\n", + i, PTR_ERR(clks[i])); + } + if (!clks[i]) + clks[i] = ERR_PTR(-EINVAL); + } + + clk_data.clks = clks; + clk_data.clk_num = clk_num; + of_clk_add_provider(np, clk_src_onecell_get, &clk_data); + + rst_ctlr.of_node = np; + rst_ctlr.nr_resets = periph_banks * 32 + num_special_reset; + reset_controller_register(&rst_ctlr); +} + +void __init tegra_init_special_resets(unsigned int num, + int (*assert)(unsigned long), + int (*deassert)(unsigned long)) +{ + num_special_reset = num; + special_reset_assert = assert; + special_reset_deassert = deassert; +} + +void tegra_register_devclks(struct tegra_devclk *dev_clks, int num) +{ + int i; + + for (i = 0; i < num; i++, dev_clks++) + clk_register_clkdev(clks[dev_clks->dt_id], dev_clks->con_id, + dev_clks->dev_id); + + for (i = 0; i < clk_num; i++) { + if (!IS_ERR_OR_NULL(clks[i])) + clk_register_clkdev(clks[i], __clk_get_name(clks[i]), + "tegra-clk-debug"); + } +} + +struct clk ** __init tegra_lookup_dt_id(int clk_id, + struct tegra_clk *tegra_clk) +{ + if (tegra_clk[clk_id].present) + return &clks[tegra_clk[clk_id].dt_id]; + else + return NULL; +} + +static struct device_node *tegra_clk_get_of_node(struct clk_hw *hw) +{ + struct device_node *np; + char *node_name; + + node_name = kstrdup_and_replace(hw->init->name, '_', '-', GFP_KERNEL); + if (!node_name) + return NULL; + + for_each_child_of_node(tegra_car_np, np) { + if (!strcmp(np->name, node_name)) + break; + } + + kfree(node_name); + + return np; +} + +struct clk *tegra_clk_dev_register(struct clk_hw *hw) +{ + struct platform_device *pdev, *parent; + const char *dev_name = NULL; + struct device *dev = NULL; + struct device_node *np; + + np = tegra_clk_get_of_node(hw); + + if (!of_device_is_available(np)) + goto put_node; + + dev_name = kasprintf(GFP_KERNEL, "tegra_clk_%s", hw->init->name); + if (!dev_name) + goto put_node; + + parent = of_find_device_by_node(tegra_car_np); + if (parent) { + pdev = of_platform_device_create(np, dev_name, &parent->dev); + put_device(&parent->dev); + + if (!pdev) { + pr_err("%s: failed to create device for %pOF\n", + __func__, np); + goto free_name; + } + + dev = &pdev->dev; + pm_runtime_enable(dev); + } else { + WARN(1, "failed to find device for %pOF\n", tegra_car_np); + } + +free_name: + kfree(dev_name); +put_node: + of_node_put(np); + + return clk_register(dev, hw); +} + +tegra_clk_apply_init_table_func tegra_clk_apply_init_table; + +static int __init tegra_clocks_apply_init_table(void) +{ + if (!tegra_clk_apply_init_table) + return 0; + + tegra_clk_apply_init_table(); + + return 0; +} +arch_initcall(tegra_clocks_apply_init_table); |