diff options
Diffstat (limited to 'drivers/clk/samsung/clk.c')
| -rw-r--r-- | drivers/clk/samsung/clk.c | 560 |
1 files changed, 560 insertions, 0 deletions
diff --git a/drivers/clk/samsung/clk.c b/drivers/clk/samsung/clk.c new file mode 100644 index 000000000..a3b251fb6 --- /dev/null +++ b/drivers/clk/samsung/clk.c @@ -0,0 +1,560 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2013 Samsung Electronics Co., Ltd. + * Copyright (c) 2013 Linaro Ltd. + * Author: Thomas Abraham <thomas.ab@samsung.com> + * + * This file includes utility functions to register clocks to common + * clock framework for Samsung platforms. + */ + +#include <linux/slab.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/io.h> +#include <linux/mfd/syscon.h> +#include <linux/of_address.h> +#include <linux/regmap.h> +#include <linux/syscore_ops.h> + +#include "clk.h" + +static LIST_HEAD(clock_reg_cache_list); + +void samsung_clk_save(void __iomem *base, + struct regmap *regmap, + struct samsung_clk_reg_dump *rd, + unsigned int num_regs) +{ + for (; num_regs > 0; --num_regs, ++rd) { + if (base) + rd->value = readl(base + rd->offset); + else if (regmap) + regmap_read(regmap, rd->offset, &rd->value); + } +} + +void samsung_clk_restore(void __iomem *base, + struct regmap *regmap, + const struct samsung_clk_reg_dump *rd, + unsigned int num_regs) +{ + for (; num_regs > 0; --num_regs, ++rd) { + if (base) + writel(rd->value, base + rd->offset); + else if (regmap) + regmap_write(regmap, rd->offset, rd->value); + } +} + +struct samsung_clk_reg_dump *samsung_clk_alloc_reg_dump( + const unsigned long *rdump, + unsigned long nr_rdump) +{ + struct samsung_clk_reg_dump *rd; + unsigned int i; + + rd = kzalloc_objs(*rd, nr_rdump); + if (!rd) + return NULL; + + for (i = 0; i < nr_rdump; ++i) + rd[i].offset = rdump[i]; + + return rd; +} + +/** + * samsung_clk_init() - Create and initialize a clock provider object + * @dev: CMU device to enable runtime PM, or NULL if RPM is not needed + * @base: Start address (mapped) of CMU registers + * @nr_clks: Total clock count to allocate in clock provider object + * + * Setup the essentials required to support clock lookup using Common Clock + * Framework. + * + * Return: Allocated and initialized clock provider object. + */ +struct samsung_clk_provider * __init samsung_clk_init(struct device *dev, + void __iomem *base, unsigned long nr_clks) +{ + struct samsung_clk_provider *ctx; + int i; + + ctx = kzalloc_flex(*ctx, clk_data.hws, nr_clks); + if (!ctx) + panic("could not allocate clock provider context.\n"); + + ctx->clk_data.num = nr_clks; + for (i = 0; i < nr_clks; ++i) + ctx->clk_data.hws[i] = ERR_PTR(-ENOENT); + + ctx->dev = dev; + ctx->reg_base = base; + spin_lock_init(&ctx->lock); + + return ctx; +} + +void __init samsung_clk_of_add_provider(struct device_node *np, + struct samsung_clk_provider *ctx) +{ + if (np) { + if (of_clk_add_hw_provider(np, of_clk_hw_onecell_get, + &ctx->clk_data)) + panic("could not register clk provider\n"); + } +} + +/* add a clock instance to the clock lookup table used for dt based lookup */ +void samsung_clk_add_lookup(struct samsung_clk_provider *ctx, + struct clk_hw *clk_hw, unsigned int id) +{ + if (id) + ctx->clk_data.hws[id] = clk_hw; +} + +/* register a list of aliases */ +void __init samsung_clk_register_alias(struct samsung_clk_provider *ctx, + const struct samsung_clock_alias *list, + unsigned int nr_clk) +{ + struct clk_hw *clk_hw; + unsigned int idx, ret; + + for (idx = 0; idx < nr_clk; idx++, list++) { + if (!list->id) { + pr_err("%s: clock id missing for index %d\n", __func__, + idx); + continue; + } + + clk_hw = ctx->clk_data.hws[list->id]; + if (!clk_hw) { + pr_err("%s: failed to find clock %d\n", __func__, + list->id); + continue; + } + + ret = clk_hw_register_clkdev(clk_hw, list->alias, + list->dev_name); + if (ret) + pr_err("%s: failed to register lookup %s\n", + __func__, list->alias); + } +} + +/* register a list of fixed clocks */ +void __init samsung_clk_register_fixed_rate(struct samsung_clk_provider *ctx, + const struct samsung_fixed_rate_clock *list, + unsigned int nr_clk) +{ + struct clk_hw *clk_hw; + unsigned int idx; + + for (idx = 0; idx < nr_clk; idx++, list++) { + clk_hw = clk_hw_register_fixed_rate(ctx->dev, list->name, + list->parent_name, list->flags, list->fixed_rate); + if (IS_ERR(clk_hw)) { + pr_err("%s: failed to register clock %s\n", __func__, + list->name); + continue; + } + + samsung_clk_add_lookup(ctx, clk_hw, list->id); + } +} + +/* register a list of fixed factor clocks */ +void __init samsung_clk_register_fixed_factor(struct samsung_clk_provider *ctx, + const struct samsung_fixed_factor_clock *list, unsigned int nr_clk) +{ + struct clk_hw *clk_hw; + unsigned int idx; + + for (idx = 0; idx < nr_clk; idx++, list++) { + clk_hw = clk_hw_register_fixed_factor(ctx->dev, list->name, + list->parent_name, list->flags, list->mult, list->div); + if (IS_ERR(clk_hw)) { + pr_err("%s: failed to register clock %s\n", __func__, + list->name); + continue; + } + + samsung_clk_add_lookup(ctx, clk_hw, list->id); + } +} + +/* register a list of mux clocks */ +void __init samsung_clk_register_mux(struct samsung_clk_provider *ctx, + const struct samsung_mux_clock *list, + unsigned int nr_clk) +{ + struct clk_hw *clk_hw; + unsigned int idx; + + for (idx = 0; idx < nr_clk; idx++, list++) { + clk_hw = clk_hw_register_mux(ctx->dev, list->name, + list->parent_names, list->num_parents, list->flags, + ctx->reg_base + list->offset, + list->shift, list->width, list->mux_flags, &ctx->lock); + if (IS_ERR(clk_hw)) { + pr_err("%s: failed to register clock %s\n", __func__, + list->name); + continue; + } + + samsung_clk_add_lookup(ctx, clk_hw, list->id); + } +} + +/* register a list of div clocks */ +void __init samsung_clk_register_div(struct samsung_clk_provider *ctx, + const struct samsung_div_clock *list, + unsigned int nr_clk) +{ + struct clk_hw *clk_hw; + unsigned int idx; + + for (idx = 0; idx < nr_clk; idx++, list++) { + if (list->table) + clk_hw = clk_hw_register_divider_table(ctx->dev, + list->name, list->parent_name, list->flags, + ctx->reg_base + list->offset, + list->shift, list->width, list->div_flags, + list->table, &ctx->lock); + else + clk_hw = clk_hw_register_divider(ctx->dev, list->name, + list->parent_name, list->flags, + ctx->reg_base + list->offset, list->shift, + list->width, list->div_flags, &ctx->lock); + if (IS_ERR(clk_hw)) { + pr_err("%s: failed to register clock %s\n", __func__, + list->name); + continue; + } + + samsung_clk_add_lookup(ctx, clk_hw, list->id); + } +} + +/* + * Some older DT's have an incorrect CMU resource size which is incompatible + * with the auto clock mode feature. In such cases we switch back to manual + * clock gating mode. + */ +bool samsung_is_auto_capable(struct device_node *np) +{ + struct resource res; + resource_size_t size; + + if (of_address_to_resource(np, 0, &res)) + return false; + + size = resource_size(&res); + if (size != 0x10000) { + pr_warn("%pOF: incorrect res size for automatic clocks\n", np); + return false; + } + return true; +} + +#define ACG_MSK GENMASK(6, 4) +#define CLK_IDLE GENMASK(5, 4) +static int samsung_auto_clk_gate_is_en(struct clk_hw *hw) +{ + u32 reg; + struct clk_gate *gate = to_clk_gate(hw); + + reg = readl(gate->reg); + return ((reg & ACG_MSK) == CLK_IDLE) ? 0 : 1; +} + +/* enable and disable are nops in automatic clock mode */ +static int samsung_auto_clk_gate_en(struct clk_hw *hw) +{ + return 0; +} + +static void samsung_auto_clk_gate_dis(struct clk_hw *hw) +{ +} + +static const struct clk_ops samsung_auto_clk_gate_ops = { + .enable = samsung_auto_clk_gate_en, + .disable = samsung_auto_clk_gate_dis, + .is_enabled = samsung_auto_clk_gate_is_en, +}; + +struct clk_hw *samsung_register_auto_gate(struct device *dev, + struct device_node *np, const char *name, + const char *parent_name, const struct clk_hw *parent_hw, + const struct clk_parent_data *parent_data, + unsigned long flags, + void __iomem *reg, u8 bit_idx, + u8 clk_gate_flags, spinlock_t *lock) +{ + struct clk_gate *gate; + struct clk_hw *hw; + struct clk_init_data init = {}; + int ret = -EINVAL; + + /* allocate the gate */ + gate = kzalloc_obj(*gate); + if (!gate) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &samsung_auto_clk_gate_ops; + init.flags = flags; + init.parent_names = parent_name ? &parent_name : NULL; + init.parent_hws = parent_hw ? &parent_hw : NULL; + init.parent_data = parent_data; + if (parent_name || parent_hw || parent_data) + init.num_parents = 1; + else + init.num_parents = 0; + + /* struct clk_gate assignments */ + gate->reg = reg; + gate->bit_idx = bit_idx; + gate->flags = clk_gate_flags; + gate->lock = lock; + gate->hw.init = &init; + + hw = &gate->hw; + if (dev || !np) + ret = clk_hw_register(dev, hw); + else if (np) + ret = of_clk_hw_register(np, hw); + if (ret) { + kfree(gate); + hw = ERR_PTR(ret); + } + + return hw; +} + +/* register a list of gate clocks */ +void __init samsung_clk_register_gate(struct samsung_clk_provider *ctx, + const struct samsung_gate_clock *list, + unsigned int nr_clk) +{ + struct clk_hw *clk_hw; + unsigned int idx; + void __iomem *reg_offs; + + for (idx = 0; idx < nr_clk; idx++, list++) { + reg_offs = ctx->reg_base + list->offset; + + if (ctx->auto_clock_gate && ctx->gate_dbg_offset) + clk_hw = samsung_register_auto_gate(ctx->dev, NULL, + list->name, list->parent_name, NULL, NULL, + list->flags, reg_offs + ctx->gate_dbg_offset, + list->bit_idx, list->gate_flags, &ctx->lock); + else + clk_hw = clk_hw_register_gate(ctx->dev, list->name, + list->parent_name, list->flags, + ctx->reg_base + list->offset, list->bit_idx, + list->gate_flags, &ctx->lock); + if (IS_ERR(clk_hw)) { + pr_err("%s: failed to register clock %s: %pe\n", __func__, + list->name, clk_hw); + continue; + } + + samsung_clk_add_lookup(ctx, clk_hw, list->id); + } +} + +/* + * obtain the clock speed of all external fixed clock sources from device + * tree and register it + */ +void __init samsung_clk_of_register_fixed_ext(struct samsung_clk_provider *ctx, + struct samsung_fixed_rate_clock *fixed_rate_clk, + unsigned int nr_fixed_rate_clk, + const struct of_device_id *clk_matches) +{ + const struct of_device_id *match; + struct device_node *clk_np; + u32 freq; + + for_each_matching_node_and_match(clk_np, clk_matches, &match) { + if (of_property_read_u32(clk_np, "clock-frequency", &freq)) + continue; + fixed_rate_clk[(unsigned long)match->data].fixed_rate = freq; + } + samsung_clk_register_fixed_rate(ctx, fixed_rate_clk, nr_fixed_rate_clk); +} + +#ifdef CONFIG_PM_SLEEP +static int samsung_clk_suspend(void *data) +{ + struct samsung_clock_reg_cache *reg_cache; + + list_for_each_entry(reg_cache, &clock_reg_cache_list, node) { + samsung_clk_save(reg_cache->reg_base, reg_cache->sysreg, + reg_cache->rdump, reg_cache->rd_num); + samsung_clk_restore(reg_cache->reg_base, reg_cache->sysreg, + reg_cache->rsuspend, + reg_cache->rsuspend_num); + } + return 0; +} + +static void samsung_clk_resume(void *data) +{ + struct samsung_clock_reg_cache *reg_cache; + + list_for_each_entry(reg_cache, &clock_reg_cache_list, node) + samsung_clk_restore(reg_cache->reg_base, reg_cache->sysreg, + reg_cache->rdump, reg_cache->rd_num); +} + +static const struct syscore_ops samsung_clk_syscore_ops = { + .suspend = samsung_clk_suspend, + .resume = samsung_clk_resume, +}; + +static struct syscore samsung_clk_syscore = { + .ops = &samsung_clk_syscore_ops, +}; + +void samsung_clk_extended_sleep_init(void __iomem *reg_base, + struct regmap *sysreg, + const unsigned long *rdump, + unsigned long nr_rdump, + const struct samsung_clk_reg_dump *rsuspend, + unsigned long nr_rsuspend) +{ + struct samsung_clock_reg_cache *reg_cache; + int i; + + reg_cache = kzalloc_flex(*reg_cache, rdump, nr_rdump); + if (!reg_cache) + panic("could not allocate register reg_cache.\n"); + + reg_cache->rd_num = nr_rdump; + + for (i = 0; i < nr_rdump; ++i) + reg_cache->rdump[i].offset = rdump[i]; + + if (list_empty(&clock_reg_cache_list)) + register_syscore(&samsung_clk_syscore); + + reg_cache->reg_base = reg_base; + reg_cache->sysreg = sysreg; + reg_cache->rsuspend = rsuspend; + reg_cache->rsuspend_num = nr_rsuspend; + list_add_tail(®_cache->node, &clock_reg_cache_list); +} +#endif + +/** + * samsung_cmu_register_clocks() - Register all clocks provided in CMU object + * @ctx: Clock provider object + * @cmu: CMU object with clocks to register + * @np: CMU device tree node + */ +void __init samsung_cmu_register_clocks(struct samsung_clk_provider *ctx, + const struct samsung_cmu_info *cmu, + struct device_node *np) +{ + if (cmu->auto_clock_gate && samsung_is_auto_capable(np)) + ctx->auto_clock_gate = cmu->auto_clock_gate; + + ctx->gate_dbg_offset = cmu->gate_dbg_offset; + ctx->option_offset = cmu->option_offset; + ctx->drcg_offset = cmu->drcg_offset; + ctx->memclk_offset = cmu->memclk_offset; + + if (cmu->pll_clks) + samsung_clk_register_pll(ctx, cmu->pll_clks, cmu->nr_pll_clks); + if (cmu->mux_clks) + samsung_clk_register_mux(ctx, cmu->mux_clks, cmu->nr_mux_clks); + if (cmu->div_clks) + samsung_clk_register_div(ctx, cmu->div_clks, cmu->nr_div_clks); + if (cmu->gate_clks) + samsung_clk_register_gate(ctx, cmu->gate_clks, + cmu->nr_gate_clks); + if (cmu->fixed_clks) + samsung_clk_register_fixed_rate(ctx, cmu->fixed_clks, + cmu->nr_fixed_clks); + if (cmu->fixed_factor_clks) + samsung_clk_register_fixed_factor(ctx, cmu->fixed_factor_clks, + cmu->nr_fixed_factor_clks); + if (cmu->cpu_clks) + samsung_clk_register_cpu(ctx, cmu->cpu_clks, cmu->nr_cpu_clks); +} + +/* Each bit enable/disables DRCG of a bus component */ +#define DRCG_EN_MSK GENMASK(31, 0) +#define MEMCLK_EN BIT(0) + +/* Enable Dynamic Root Clock Gating (DRCG) of bus components */ +void samsung_en_dyn_root_clk_gating(struct device_node *np, + struct samsung_clk_provider *ctx, + const struct samsung_cmu_info *cmu, + bool cmu_has_pm) +{ + if (!ctx->auto_clock_gate) + return; + + ctx->sysreg = syscon_regmap_lookup_by_phandle(np, "samsung,sysreg"); + if (IS_ERR(ctx->sysreg)) { + pr_warn("%pOF: Unable to get CMU sysreg\n", np); + ctx->sysreg = NULL; + } else { + /* Enable DRCG for all bus components */ + regmap_write(ctx->sysreg, ctx->drcg_offset, DRCG_EN_MSK); + /* Enable memclk gate (not present on all sysreg) */ + if (ctx->memclk_offset) + regmap_write_bits(ctx->sysreg, ctx->memclk_offset, + MEMCLK_EN, 0x0); + + if (!cmu_has_pm) + /* + * When a CMU has PM support, clocks are saved/restored + * via its PM handlers, so only register them with the + * syscore suspend / resume paths if PM is not in use. + */ + samsung_clk_extended_sleep_init(NULL, ctx->sysreg, + cmu->sysreg_clk_regs, + cmu->nr_sysreg_clk_regs, + NULL, 0); + } +} + +/* + * Common function which registers plls, muxes, dividers and gates + * for each CMU. It also add CMU register list to register cache. + */ +struct samsung_clk_provider * __init samsung_cmu_register_one( + struct device_node *np, + const struct samsung_cmu_info *cmu) +{ + void __iomem *reg_base; + struct samsung_clk_provider *ctx; + + reg_base = of_iomap(np, 0); + if (!reg_base) { + panic("%s: failed to map registers\n", __func__); + return NULL; + } + + ctx = samsung_clk_init(NULL, reg_base, cmu->nr_clk_ids); + samsung_cmu_register_clocks(ctx, cmu, np); + + if (cmu->clk_regs) + samsung_clk_extended_sleep_init(reg_base, NULL, + cmu->clk_regs, cmu->nr_clk_regs, + cmu->suspend_regs, cmu->nr_suspend_regs); + + samsung_clk_of_add_provider(np, ctx); + + /* sysreg DT nodes reference a clock in this CMU */ + samsung_en_dyn_root_clk_gating(np, ctx, cmu, false); + + return ctx; +} |