diff options
Diffstat (limited to 'drivers/clk/renesas/renesas-cpg-mssr.c')
-rw-r--r-- | drivers/clk/renesas/renesas-cpg-mssr.c | 601 |
1 files changed, 601 insertions, 0 deletions
diff --git a/drivers/clk/renesas/renesas-cpg-mssr.c b/drivers/clk/renesas/renesas-cpg-mssr.c new file mode 100644 index 000000000000..58e24b326a48 --- /dev/null +++ b/drivers/clk/renesas/renesas-cpg-mssr.c @@ -0,0 +1,601 @@ +/* + * Renesas Clock Pulse Generator / Module Standby and Software Reset + * + * Copyright (C) 2015 Glider bvba + * + * Based on clk-mstp.c, clk-rcar-gen2.c, and clk-rcar-gen3.c + * + * Copyright (C) 2013 Ideas On Board SPRL + * Copyright (C) 2015 Renesas Electronics Corp. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + */ + +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/device.h> +#include <linux/init.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_clock.h> +#include <linux/pm_domain.h> +#include <linux/slab.h> + +#include <dt-bindings/clock/renesas-cpg-mssr.h> + +#include "renesas-cpg-mssr.h" +#include "clk-div6.h" + +#ifdef DEBUG +#define WARN_DEBUG(x) do { } while (0) +#else +#define WARN_DEBUG(x) WARN_ON(x) +#endif + + +/* + * Module Standby and Software Reset register offets. + * + * If the registers exist, these are valid for SH-Mobile, R-Mobile, + * R-Car Gen 2, and R-Car Gen 3. + * These are NOT valid for R-Car Gen1 and RZ/A1! + */ + +/* + * Module Stop Status Register offsets + */ + +static const u16 mstpsr[] = { + 0x030, 0x038, 0x040, 0x048, 0x04C, 0x03C, 0x1C0, 0x1C4, + 0x9A0, 0x9A4, 0x9A8, 0x9AC, +}; + +#define MSTPSR(i) mstpsr[i] + + +/* + * System Module Stop Control Register offsets + */ + +static const u16 smstpcr[] = { + 0x130, 0x134, 0x138, 0x13C, 0x140, 0x144, 0x148, 0x14C, + 0x990, 0x994, 0x998, 0x99C, +}; + +#define SMSTPCR(i) smstpcr[i] + + +/* + * Software Reset Register offsets + */ + +static const u16 srcr[] = { + 0x0A0, 0x0A8, 0x0B0, 0x0B8, 0x0BC, 0x0C4, 0x1C8, 0x1CC, + 0x920, 0x924, 0x928, 0x92C, +}; + +#define SRCR(i) srcr[i] + + +/* Realtime Module Stop Control Register offsets */ +#define RMSTPCR(i) (smstpcr[i] - 0x20) + +/* Modem Module Stop Control Register offsets (r8a73a4) */ +#define MMSTPCR(i) (smstpcr[i] + 0x20) + +/* Software Reset Clearing Register offsets */ +#define SRSTCLR(i) (0x940 + (i) * 4) + + +/** + * Clock Pulse Generator / Module Standby and Software Reset Private Data + * + * @dev: CPG/MSSR device + * @base: CPG/MSSR register block base address + * @mstp_lock: protects writes to SMSTPCR + * @clks: Array containing all Core and Module Clocks + * @num_core_clks: Number of Core Clocks in clks[] + * @num_mod_clks: Number of Module Clocks in clks[] + * @last_dt_core_clk: ID of the last Core Clock exported to DT + */ +struct cpg_mssr_priv { + struct device *dev; + void __iomem *base; + spinlock_t mstp_lock; + + struct clk **clks; + unsigned int num_core_clks; + unsigned int num_mod_clks; + unsigned int last_dt_core_clk; +}; + + +/** + * struct mstp_clock - MSTP gating clock + * @hw: handle between common and hardware-specific interfaces + * @index: MSTP clock number + * @priv: CPG/MSSR private data + */ +struct mstp_clock { + struct clk_hw hw; + u32 index; + struct cpg_mssr_priv *priv; +}; + +#define to_mstp_clock(_hw) container_of(_hw, struct mstp_clock, hw) + +static int cpg_mstp_clock_endisable(struct clk_hw *hw, bool enable) +{ + struct mstp_clock *clock = to_mstp_clock(hw); + struct cpg_mssr_priv *priv = clock->priv; + unsigned int reg = clock->index / 32; + unsigned int bit = clock->index % 32; + struct device *dev = priv->dev; + u32 bitmask = BIT(bit); + unsigned long flags; + unsigned int i; + u32 value; + + dev_dbg(dev, "MSTP %u%02u/%pC %s\n", reg, bit, hw->clk, + enable ? "ON" : "OFF"); + spin_lock_irqsave(&priv->mstp_lock, flags); + + value = clk_readl(priv->base + SMSTPCR(reg)); + if (enable) + value &= ~bitmask; + else + value |= bitmask; + clk_writel(value, priv->base + SMSTPCR(reg)); + + spin_unlock_irqrestore(&priv->mstp_lock, flags); + + if (!enable) + return 0; + + for (i = 1000; i > 0; --i) { + if (!(clk_readl(priv->base + MSTPSR(reg)) & + bitmask)) + break; + cpu_relax(); + } + + if (!i) { + dev_err(dev, "Failed to enable SMSTP %p[%d]\n", + priv->base + SMSTPCR(reg), bit); + return -ETIMEDOUT; + } + + return 0; +} + +static int cpg_mstp_clock_enable(struct clk_hw *hw) +{ + return cpg_mstp_clock_endisable(hw, true); +} + +static void cpg_mstp_clock_disable(struct clk_hw *hw) +{ + cpg_mstp_clock_endisable(hw, false); +} + +static int cpg_mstp_clock_is_enabled(struct clk_hw *hw) +{ + struct mstp_clock *clock = to_mstp_clock(hw); + struct cpg_mssr_priv *priv = clock->priv; + u32 value; + + value = clk_readl(priv->base + MSTPSR(clock->index / 32)); + + return !(value & BIT(clock->index % 32)); +} + +static const struct clk_ops cpg_mstp_clock_ops = { + .enable = cpg_mstp_clock_enable, + .disable = cpg_mstp_clock_disable, + .is_enabled = cpg_mstp_clock_is_enabled, +}; + +static +struct clk *cpg_mssr_clk_src_twocell_get(struct of_phandle_args *clkspec, + void *data) +{ + unsigned int clkidx = clkspec->args[1]; + struct cpg_mssr_priv *priv = data; + struct device *dev = priv->dev; + unsigned int idx; + const char *type; + struct clk *clk; + + switch (clkspec->args[0]) { + case CPG_CORE: + type = "core"; + if (clkidx > priv->last_dt_core_clk) { + dev_err(dev, "Invalid %s clock index %u\n", type, + clkidx); + return ERR_PTR(-EINVAL); + } + clk = priv->clks[clkidx]; + break; + + case CPG_MOD: + type = "module"; + idx = MOD_CLK_PACK(clkidx); + if (clkidx % 100 > 31 || idx >= priv->num_mod_clks) { + dev_err(dev, "Invalid %s clock index %u\n", type, + clkidx); + return ERR_PTR(-EINVAL); + } + clk = priv->clks[priv->num_core_clks + idx]; + break; + + default: + dev_err(dev, "Invalid CPG clock type %u\n", clkspec->args[0]); + return ERR_PTR(-EINVAL); + } + + if (IS_ERR(clk)) + dev_err(dev, "Cannot get %s clock %u: %ld", type, clkidx, + PTR_ERR(clk)); + else + dev_dbg(dev, "clock (%u, %u) is %pC at %pCr Hz\n", + clkspec->args[0], clkspec->args[1], clk, clk); + return clk; +} + +static void __init cpg_mssr_register_core_clk(const struct cpg_core_clk *core, + const struct cpg_mssr_info *info, + struct cpg_mssr_priv *priv) +{ + struct clk *clk = NULL, *parent; + struct device *dev = priv->dev; + unsigned int id = core->id; + const char *parent_name; + + WARN_DEBUG(id >= priv->num_core_clks); + WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT); + + switch (core->type) { + case CLK_TYPE_IN: + clk = of_clk_get_by_name(priv->dev->of_node, core->name); + break; + + case CLK_TYPE_FF: + case CLK_TYPE_DIV6P1: + WARN_DEBUG(core->parent >= priv->num_core_clks); + parent = priv->clks[core->parent]; + if (IS_ERR(parent)) { + clk = parent; + goto fail; + } + + parent_name = __clk_get_name(parent); + if (core->type == CLK_TYPE_FF) { + clk = clk_register_fixed_factor(NULL, core->name, + parent_name, 0, + core->mult, core->div); + } else { + clk = cpg_div6_register(core->name, 1, &parent_name, + priv->base + core->offset); + } + break; + + default: + if (info->cpg_clk_register) + clk = info->cpg_clk_register(dev, core, info, + priv->clks, priv->base); + else + dev_err(dev, "%s has unsupported core clock type %u\n", + core->name, core->type); + break; + } + + if (IS_ERR_OR_NULL(clk)) + goto fail; + + dev_dbg(dev, "Core clock %pC at %pCr Hz\n", clk, clk); + priv->clks[id] = clk; + return; + +fail: + dev_err(dev, "Failed to register %s clock %s: %ld\n", "core,", + core->name, PTR_ERR(clk)); +} + +static void __init cpg_mssr_register_mod_clk(const struct mssr_mod_clk *mod, + const struct cpg_mssr_info *info, + struct cpg_mssr_priv *priv) +{ + struct mstp_clock *clock = NULL; + struct device *dev = priv->dev; + unsigned int id = mod->id; + struct clk_init_data init; + struct clk *parent, *clk; + const char *parent_name; + unsigned int i; + + WARN_DEBUG(id < priv->num_core_clks); + WARN_DEBUG(id >= priv->num_core_clks + priv->num_mod_clks); + WARN_DEBUG(mod->parent >= priv->num_core_clks + priv->num_mod_clks); + WARN_DEBUG(PTR_ERR(priv->clks[id]) != -ENOENT); + + parent = priv->clks[mod->parent]; + if (IS_ERR(parent)) { + clk = parent; + goto fail; + } + + clock = kzalloc(sizeof(*clock), GFP_KERNEL); + if (!clock) { + clk = ERR_PTR(-ENOMEM); + goto fail; + } + + init.name = mod->name; + init.ops = &cpg_mstp_clock_ops; + init.flags = CLK_IS_BASIC | CLK_SET_RATE_PARENT; + for (i = 0; i < info->num_crit_mod_clks; i++) + if (id == info->crit_mod_clks[i]) { +#ifdef CLK_ENABLE_HAND_OFF + dev_dbg(dev, "MSTP %s setting CLK_ENABLE_HAND_OFF\n", + mod->name); + init.flags |= CLK_ENABLE_HAND_OFF; + break; +#else + dev_dbg(dev, "Ignoring MSTP %s to prevent disabling\n", + mod->name); + kfree(clock); + return; +#endif + } + + parent_name = __clk_get_name(parent); + init.parent_names = &parent_name; + init.num_parents = 1; + + clock->index = id - priv->num_core_clks; + clock->priv = priv; + clock->hw.init = &init; + + clk = clk_register(NULL, &clock->hw); + if (IS_ERR(clk)) + goto fail; + + dev_dbg(dev, "Module clock %pC at %pCr Hz\n", clk, clk); + priv->clks[id] = clk; + return; + +fail: + dev_err(dev, "Failed to register %s clock %s: %ld\n", "module,", + mod->name, PTR_ERR(clk)); + kfree(clock); +} + + +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF +struct cpg_mssr_clk_domain { + struct generic_pm_domain genpd; + struct device_node *np; + unsigned int num_core_pm_clks; + unsigned int core_pm_clks[0]; +}; + +static bool cpg_mssr_is_pm_clk(const struct of_phandle_args *clkspec, + struct cpg_mssr_clk_domain *pd) +{ + unsigned int i; + + if (clkspec->np != pd->np || clkspec->args_count != 2) + return false; + + switch (clkspec->args[0]) { + case CPG_CORE: + for (i = 0; i < pd->num_core_pm_clks; i++) + if (clkspec->args[1] == pd->core_pm_clks[i]) + return true; + return false; + + case CPG_MOD: + return true; + + default: + return false; + } +} + +static int cpg_mssr_attach_dev(struct generic_pm_domain *genpd, + struct device *dev) +{ + struct cpg_mssr_clk_domain *pd = + container_of(genpd, struct cpg_mssr_clk_domain, genpd); + struct device_node *np = dev->of_node; + struct of_phandle_args clkspec; + struct clk *clk; + int i = 0; + int error; + + while (!of_parse_phandle_with_args(np, "clocks", "#clock-cells", i, + &clkspec)) { + if (cpg_mssr_is_pm_clk(&clkspec, pd)) + goto found; + + of_node_put(clkspec.np); + i++; + } + + return 0; + +found: + clk = of_clk_get_from_provider(&clkspec); + of_node_put(clkspec.np); + + if (IS_ERR(clk)) + return PTR_ERR(clk); + + error = pm_clk_create(dev); + if (error) { + dev_err(dev, "pm_clk_create failed %d\n", error); + goto fail_put; + } + + error = pm_clk_add_clk(dev, clk); + if (error) { + dev_err(dev, "pm_clk_add_clk %pC failed %d\n", clk, error); + goto fail_destroy; + } + + return 0; + +fail_destroy: + pm_clk_destroy(dev); +fail_put: + clk_put(clk); + return error; +} + +static void cpg_mssr_detach_dev(struct generic_pm_domain *genpd, + struct device *dev) +{ + if (!list_empty(&dev->power.subsys_data->clock_list)) + pm_clk_destroy(dev); +} + +static int __init cpg_mssr_add_clk_domain(struct device *dev, + const unsigned int *core_pm_clks, + unsigned int num_core_pm_clks) +{ + struct device_node *np = dev->of_node; + struct generic_pm_domain *genpd; + struct cpg_mssr_clk_domain *pd; + size_t pm_size = num_core_pm_clks * sizeof(core_pm_clks[0]); + + pd = devm_kzalloc(dev, sizeof(*pd) + pm_size, GFP_KERNEL); + if (!pd) + return -ENOMEM; + + pd->np = np; + pd->num_core_pm_clks = num_core_pm_clks; + memcpy(pd->core_pm_clks, core_pm_clks, pm_size); + + genpd = &pd->genpd; + genpd->name = np->name; + genpd->flags = GENPD_FLAG_PM_CLK; + pm_genpd_init(genpd, &simple_qos_governor, false); + genpd->attach_dev = cpg_mssr_attach_dev; + genpd->detach_dev = cpg_mssr_detach_dev; + + of_genpd_add_provider_simple(np, genpd); + return 0; +} +#else +static inline int cpg_mssr_add_clk_domain(struct device *dev, + const unsigned int *core_pm_clks, + unsigned int num_core_pm_clks) +{ + return 0; +} +#endif /* !CONFIG_PM_GENERIC_DOMAINS_OF */ + + +static const struct of_device_id cpg_mssr_match[] = { +#ifdef CONFIG_ARCH_R8A7795 + { + .compatible = "renesas,r8a7795-cpg-mssr", + .data = &r8a7795_cpg_mssr_info, + }, +#endif + { /* sentinel */ } +}; + +static void cpg_mssr_del_clk_provider(void *data) +{ + of_clk_del_provider(data); +} + +static int __init cpg_mssr_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + const struct cpg_mssr_info *info; + struct cpg_mssr_priv *priv; + unsigned int nclks, i; + struct resource *res; + struct clk **clks; + int error; + + info = of_match_node(cpg_mssr_match, np)->data; + if (info->init) { + error = info->init(dev); + if (error) + return error; + } + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = dev; + spin_lock_init(&priv->mstp_lock); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->base = devm_ioremap_resource(dev, res); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + nclks = info->num_total_core_clks + info->num_hw_mod_clks; + clks = devm_kmalloc_array(dev, nclks, sizeof(*clks), GFP_KERNEL); + if (!clks) + return -ENOMEM; + + priv->clks = clks; + priv->num_core_clks = info->num_total_core_clks; + priv->num_mod_clks = info->num_hw_mod_clks; + priv->last_dt_core_clk = info->last_dt_core_clk; + + for (i = 0; i < nclks; i++) + clks[i] = ERR_PTR(-ENOENT); + + for (i = 0; i < info->num_core_clks; i++) + cpg_mssr_register_core_clk(&info->core_clks[i], info, priv); + + for (i = 0; i < info->num_mod_clks; i++) + cpg_mssr_register_mod_clk(&info->mod_clks[i], info, priv); + + error = of_clk_add_provider(np, cpg_mssr_clk_src_twocell_get, priv); + if (error) + return error; + + error = devm_add_action_or_reset(dev, + cpg_mssr_del_clk_provider, + np); + if (error) + return error; + + error = cpg_mssr_add_clk_domain(dev, info->core_pm_clks, + info->num_core_pm_clks); + if (error) + return error; + + return 0; +} + +static struct platform_driver cpg_mssr_driver = { + .driver = { + .name = "renesas-cpg-mssr", + .of_match_table = cpg_mssr_match, + }, +}; + +static int __init cpg_mssr_init(void) +{ + return platform_driver_probe(&cpg_mssr_driver, cpg_mssr_probe); +} + +subsys_initcall(cpg_mssr_init); + +MODULE_DESCRIPTION("Renesas CPG/MSSR Driver"); +MODULE_LICENSE("GPL v2"); |