diff options
Diffstat (limited to 'drivers/clk/davinci/psc.c')
| -rw-r--r-- | drivers/clk/davinci/psc.c | 595 |
1 files changed, 595 insertions, 0 deletions
diff --git a/drivers/clk/davinci/psc.c b/drivers/clk/davinci/psc.c new file mode 100644 index 000000000..fffbed5e2 --- /dev/null +++ b/drivers/clk/davinci/psc.c @@ -0,0 +1,595 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Clock driver for TI Davinci PSC controllers + * + * Copyright (C) 2017 David Lechner <david@lechnology.com> + * + * Based on: drivers/clk/keystone/gate.c + * Copyright (C) 2013 Texas Instruments. + * Murali Karicheri <m-karicheri2@ti.com> + * Santosh Shilimkar <santosh.shilimkar@ti.com> + * + * And: arch/arm/mach-davinci/psc.c + * Copyright (C) 2006 Texas Instruments. + */ + +#include <linux/clk-provider.h> +#include <linux/clk.h> +#include <linux/clk/davinci.h> +#include <linux/clkdev.h> +#include <linux/err.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_clock.h> +#include <linux/pm_domain.h> +#include <linux/regmap.h> +#include <linux/reset-controller.h> +#include <linux/slab.h> +#include <linux/types.h> + +#include "psc.h" + +/* PSC register offsets */ +#define EPCPR 0x070 +#define PTCMD 0x120 +#define PTSTAT 0x128 +#define PDSTAT(n) (0x200 + 4 * (n)) +#define PDCTL(n) (0x300 + 4 * (n)) +#define MDSTAT(n) (0x800 + 4 * (n)) +#define MDCTL(n) (0xa00 + 4 * (n)) + +/* PSC module states */ +enum davinci_lpsc_state { + LPSC_STATE_SWRSTDISABLE = 0, + LPSC_STATE_SYNCRST = 1, + LPSC_STATE_DISABLE = 2, + LPSC_STATE_ENABLE = 3, +}; + +#define MDSTAT_STATE_MASK GENMASK(5, 0) +#define MDSTAT_MCKOUT BIT(12) +#define PDSTAT_STATE_MASK GENMASK(4, 0) +#define MDCTL_FORCE BIT(31) +#define MDCTL_LRESET BIT(8) +#define PDCTL_EPCGOOD BIT(8) +#define PDCTL_NEXT BIT(0) + +struct davinci_psc_data { + struct clk_onecell_data clk_data; + struct genpd_onecell_data pm_data; + struct reset_controller_dev rcdev; +}; + +/** + * struct davinci_lpsc_clk - LPSC clock structure + * @dev: the device that provides this LPSC or NULL + * @hw: clk_hw for the LPSC + * @pm_domain: power domain for the LPSC + * @genpd_clk: clock reference owned by @pm_domain + * @regmap: PSC MMIO region + * @md: Module domain (LPSC module id) + * @pd: Power domain + * @flags: LPSC_* quirk flags + */ +struct davinci_lpsc_clk { + struct device *dev; + struct clk_hw hw; + struct generic_pm_domain pm_domain; + struct clk *genpd_clk; + struct regmap *regmap; + u32 md; + u32 pd; + u32 flags; +}; + +#define to_davinci_psc_data(x) container_of(x, struct davinci_psc_data, x) +#define to_davinci_lpsc_clk(x) container_of(x, struct davinci_lpsc_clk, x) + +/** + * best_dev_name - get the "best" device name. + * @dev: the device + * + * Returns the device tree compatible name if the device has a DT node, + * otherwise return the device name. This is mainly needed because clkdev + * lookups are limited to 20 chars for dev_id and when using device tree, + * dev_name(dev) is much longer than that. + */ +static inline const char *best_dev_name(struct device *dev) +{ + const char *compatible; + + if (!of_property_read_string(dev->of_node, "compatible", &compatible)) + return compatible; + + return dev_name(dev); +} + +static void davinci_lpsc_config(struct davinci_lpsc_clk *lpsc, + enum davinci_lpsc_state next_state) +{ + u32 epcpr, pdstat, mdstat, ptstat; + + regmap_write_bits(lpsc->regmap, MDCTL(lpsc->md), MDSTAT_STATE_MASK, + next_state); + + if (lpsc->flags & LPSC_FORCE) + regmap_write_bits(lpsc->regmap, MDCTL(lpsc->md), MDCTL_FORCE, + MDCTL_FORCE); + + regmap_read(lpsc->regmap, PDSTAT(lpsc->pd), &pdstat); + if ((pdstat & PDSTAT_STATE_MASK) == 0) { + regmap_write_bits(lpsc->regmap, PDCTL(lpsc->pd), PDCTL_NEXT, + PDCTL_NEXT); + + regmap_write(lpsc->regmap, PTCMD, BIT(lpsc->pd)); + + regmap_read_poll_timeout(lpsc->regmap, EPCPR, epcpr, + epcpr & BIT(lpsc->pd), 0, 0); + + regmap_write_bits(lpsc->regmap, PDCTL(lpsc->pd), PDCTL_EPCGOOD, + PDCTL_EPCGOOD); + } else { + regmap_write(lpsc->regmap, PTCMD, BIT(lpsc->pd)); + } + + regmap_read_poll_timeout(lpsc->regmap, PTSTAT, ptstat, + !(ptstat & BIT(lpsc->pd)), 0, 0); + + regmap_read_poll_timeout(lpsc->regmap, MDSTAT(lpsc->md), mdstat, + (mdstat & MDSTAT_STATE_MASK) == next_state, + 0, 0); +} + +static int davinci_lpsc_clk_enable(struct clk_hw *hw) +{ + struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(hw); + + davinci_lpsc_config(lpsc, LPSC_STATE_ENABLE); + + return 0; +} + +static void davinci_lpsc_clk_disable(struct clk_hw *hw) +{ + struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(hw); + + davinci_lpsc_config(lpsc, LPSC_STATE_DISABLE); +} + +static int davinci_lpsc_clk_is_enabled(struct clk_hw *hw) +{ + struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(hw); + u32 mdstat; + + regmap_read(lpsc->regmap, MDSTAT(lpsc->md), &mdstat); + + return (mdstat & MDSTAT_MCKOUT) ? 1 : 0; +} + +static const struct clk_ops davinci_lpsc_clk_ops = { + .enable = davinci_lpsc_clk_enable, + .disable = davinci_lpsc_clk_disable, + .is_enabled = davinci_lpsc_clk_is_enabled, +}; + +static int davinci_psc_genpd_attach_dev(struct generic_pm_domain *pm_domain, + struct device *dev) +{ + struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(pm_domain); + struct clk *clk; + int ret; + + /* + * pm_clk_remove_clk() will call clk_put(), so we have to use clk_get() + * to get the clock instead of using lpsc->hw.clk directly. + */ + clk = clk_get_sys(best_dev_name(lpsc->dev), clk_hw_get_name(&lpsc->hw)); + if (IS_ERR(clk)) + return (PTR_ERR(clk)); + + ret = pm_clk_create(dev); + if (ret < 0) + goto fail_clk_put; + + ret = pm_clk_add_clk(dev, clk); + if (ret < 0) + goto fail_pm_clk_destroy; + + lpsc->genpd_clk = clk; + + return 0; + +fail_pm_clk_destroy: + pm_clk_destroy(dev); +fail_clk_put: + clk_put(clk); + + return ret; +} + +static void davinci_psc_genpd_detach_dev(struct generic_pm_domain *pm_domain, + struct device *dev) +{ + struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(pm_domain); + + pm_clk_remove_clk(dev, lpsc->genpd_clk); + pm_clk_destroy(dev); + + lpsc->genpd_clk = NULL; +} + +/** + * davinci_lpsc_clk_register - register LPSC clock + * @dev: the clocks's device or NULL + * @name: name of this clock + * @parent_name: name of clock's parent + * @regmap: PSC MMIO region + * @md: local PSC number + * @pd: power domain + * @flags: LPSC_* flags + */ +static struct davinci_lpsc_clk * +davinci_lpsc_clk_register(struct device *dev, const char *name, + const char *parent_name, struct regmap *regmap, + u32 md, u32 pd, u32 flags) +{ + struct clk_init_data init; + struct davinci_lpsc_clk *lpsc; + int ret; + bool is_on; + + lpsc = kzalloc(sizeof(*lpsc), GFP_KERNEL); + if (!lpsc) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &davinci_lpsc_clk_ops; + init.parent_names = (parent_name ? &parent_name : NULL); + init.num_parents = (parent_name ? 1 : 0); + init.flags = 0; + + if (flags & LPSC_ALWAYS_ENABLED) + init.flags |= CLK_IS_CRITICAL; + + if (flags & LPSC_SET_RATE_PARENT) + init.flags |= CLK_SET_RATE_PARENT; + + lpsc->dev = dev; + lpsc->regmap = regmap; + lpsc->hw.init = &init; + lpsc->md = md; + lpsc->pd = pd; + lpsc->flags = flags; + + ret = clk_hw_register(dev, &lpsc->hw); + if (ret < 0) { + kfree(lpsc); + return ERR_PTR(ret); + } + + /* for now, genpd is only registered when using device-tree */ + if (!dev || !dev->of_node) + return lpsc; + + /* genpd attach needs a way to look up this clock */ + ret = clk_hw_register_clkdev(&lpsc->hw, name, best_dev_name(dev)); + + lpsc->pm_domain.name = devm_kasprintf(dev, GFP_KERNEL, "%s: %s", + best_dev_name(dev), name); + lpsc->pm_domain.attach_dev = davinci_psc_genpd_attach_dev; + lpsc->pm_domain.detach_dev = davinci_psc_genpd_detach_dev; + lpsc->pm_domain.flags = GENPD_FLAG_PM_CLK; + + is_on = davinci_lpsc_clk_is_enabled(&lpsc->hw); + pm_genpd_init(&lpsc->pm_domain, NULL, is_on); + + return lpsc; +} + +static int davinci_lpsc_clk_reset(struct clk *clk, bool reset) +{ + struct clk_hw *hw = __clk_get_hw(clk); + struct davinci_lpsc_clk *lpsc = to_davinci_lpsc_clk(hw); + u32 mdctl; + + if (IS_ERR_OR_NULL(lpsc)) + return -EINVAL; + + mdctl = reset ? 0 : MDCTL_LRESET; + regmap_write_bits(lpsc->regmap, MDCTL(lpsc->md), MDCTL_LRESET, mdctl); + + return 0; +} + +/* + * REVISIT: These exported functions can be removed after a non-DT lookup is + * added to the reset controller framework and the davinci-rproc driver is + * updated to use the generic reset controller framework. + */ + +int davinci_clk_reset_assert(struct clk *clk) +{ + return davinci_lpsc_clk_reset(clk, true); +} +EXPORT_SYMBOL(davinci_clk_reset_assert); + +int davinci_clk_reset_deassert(struct clk *clk) +{ + return davinci_lpsc_clk_reset(clk, false); +} +EXPORT_SYMBOL(davinci_clk_reset_deassert); + +static int davinci_psc_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct davinci_psc_data *psc = to_davinci_psc_data(rcdev); + struct clk *clk = psc->clk_data.clks[id]; + + return davinci_lpsc_clk_reset(clk, true); +} + +static int davinci_psc_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct davinci_psc_data *psc = to_davinci_psc_data(rcdev); + struct clk *clk = psc->clk_data.clks[id]; + + return davinci_lpsc_clk_reset(clk, false); +} + +static const struct reset_control_ops davinci_psc_reset_ops = { + .assert = davinci_psc_reset_assert, + .deassert = davinci_psc_reset_deassert, +}; + +static int davinci_psc_reset_of_xlate(struct reset_controller_dev *rcdev, + const struct of_phandle_args *reset_spec) +{ + struct of_phandle_args clkspec = *reset_spec; /* discard const qualifier */ + struct clk *clk; + struct clk_hw *hw; + struct davinci_lpsc_clk *lpsc; + + /* the clock node is the same as the reset node */ + clk = of_clk_get_from_provider(&clkspec); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + hw = __clk_get_hw(clk); + lpsc = to_davinci_lpsc_clk(hw); + clk_put(clk); + + /* not all modules support local reset */ + if (!(lpsc->flags & LPSC_LOCAL_RESET)) + return -EINVAL; + + return lpsc->md; +} + +static const struct regmap_config davinci_psc_regmap_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, +}; + +static struct davinci_psc_data * +__davinci_psc_register_clocks(struct device *dev, + const struct davinci_lpsc_clk_info *info, + int num_clks, + void __iomem *base) +{ + struct davinci_psc_data *psc; + struct clk **clks; + struct generic_pm_domain **pm_domains; + struct regmap *regmap; + int i, ret; + + psc = kzalloc(sizeof(*psc), GFP_KERNEL); + if (!psc) + return ERR_PTR(-ENOMEM); + + clks = kmalloc_array(num_clks, sizeof(*clks), GFP_KERNEL); + if (!clks) { + ret = -ENOMEM; + goto err_free_psc; + } + + psc->clk_data.clks = clks; + psc->clk_data.clk_num = num_clks; + + /* + * init array with error so that of_clk_src_onecell_get() doesn't + * return NULL for gaps in the sparse array + */ + for (i = 0; i < num_clks; i++) + clks[i] = ERR_PTR(-ENOENT); + + pm_domains = kcalloc(num_clks, sizeof(*pm_domains), GFP_KERNEL); + if (!pm_domains) { + ret = -ENOMEM; + goto err_free_clks; + } + + psc->pm_data.domains = pm_domains; + psc->pm_data.num_domains = num_clks; + + regmap = regmap_init_mmio(dev, base, &davinci_psc_regmap_config); + if (IS_ERR(regmap)) { + ret = PTR_ERR(regmap); + goto err_free_pm_domains; + } + + for (; info->name; info++) { + struct davinci_lpsc_clk *lpsc; + + lpsc = davinci_lpsc_clk_register(dev, info->name, info->parent, + regmap, info->md, info->pd, + info->flags); + if (IS_ERR(lpsc)) { + dev_warn(dev, "Failed to register %s (%ld)\n", + info->name, PTR_ERR(lpsc)); + continue; + } + + clks[info->md] = lpsc->hw.clk; + pm_domains[info->md] = &lpsc->pm_domain; + } + + /* + * for now, a reset controller is only registered when there is a device + * to associate it with. + */ + if (!dev) + return psc; + + psc->rcdev.ops = &davinci_psc_reset_ops; + psc->rcdev.owner = THIS_MODULE; + psc->rcdev.dev = dev; + psc->rcdev.of_node = dev->of_node; + psc->rcdev.of_reset_n_cells = 1; + psc->rcdev.of_xlate = davinci_psc_reset_of_xlate; + psc->rcdev.nr_resets = num_clks; + + ret = devm_reset_controller_register(dev, &psc->rcdev); + if (ret < 0) + dev_warn(dev, "Failed to register reset controller (%d)\n", ret); + + return psc; + +err_free_pm_domains: + kfree(pm_domains); +err_free_clks: + kfree(clks); +err_free_psc: + kfree(psc); + + return ERR_PTR(ret); +} + +int davinci_psc_register_clocks(struct device *dev, + const struct davinci_lpsc_clk_info *info, + u8 num_clks, + void __iomem *base) +{ + struct davinci_psc_data *psc; + + psc = __davinci_psc_register_clocks(dev, info, num_clks, base); + if (IS_ERR(psc)) + return PTR_ERR(psc); + + for (; info->name; info++) { + const struct davinci_lpsc_clkdev_info *cdevs = info->cdevs; + struct clk *clk = psc->clk_data.clks[info->md]; + + if (!cdevs || IS_ERR_OR_NULL(clk)) + continue; + + for (; cdevs->con_id || cdevs->dev_id; cdevs++) + clk_register_clkdev(clk, cdevs->con_id, cdevs->dev_id); + } + + return 0; +} + +int of_davinci_psc_clk_init(struct device *dev, + const struct davinci_lpsc_clk_info *info, + u8 num_clks, + void __iomem *base) +{ + struct device_node *node = dev->of_node; + struct davinci_psc_data *psc; + + psc = __davinci_psc_register_clocks(dev, info, num_clks, base); + if (IS_ERR(psc)) + return PTR_ERR(psc); + + of_genpd_add_provider_onecell(node, &psc->pm_data); + + of_clk_add_provider(node, of_clk_src_onecell_get, &psc->clk_data); + + return 0; +} + +static const struct of_device_id davinci_psc_of_match[] = { +#ifdef CONFIG_ARCH_DAVINCI_DA850 + { .compatible = "ti,da850-psc0", .data = &of_da850_psc0_init_data }, + { .compatible = "ti,da850-psc1", .data = &of_da850_psc1_init_data }, +#endif + { } +}; + +static const struct platform_device_id davinci_psc_id_table[] = { +#ifdef CONFIG_ARCH_DAVINCI_DA830 + { .name = "da830-psc0", .driver_data = (kernel_ulong_t)&da830_psc0_init_data }, + { .name = "da830-psc1", .driver_data = (kernel_ulong_t)&da830_psc1_init_data }, +#endif +#ifdef CONFIG_ARCH_DAVINCI_DA850 + { .name = "da850-psc0", .driver_data = (kernel_ulong_t)&da850_psc0_init_data }, + { .name = "da850-psc1", .driver_data = (kernel_ulong_t)&da850_psc1_init_data }, +#endif +#ifdef CONFIG_ARCH_DAVINCI_DM355 + { .name = "dm355-psc", .driver_data = (kernel_ulong_t)&dm355_psc_init_data }, +#endif +#ifdef CONFIG_ARCH_DAVINCI_DM365 + { .name = "dm365-psc", .driver_data = (kernel_ulong_t)&dm365_psc_init_data }, +#endif +#ifdef CONFIG_ARCH_DAVINCI_DM644x + { .name = "dm644x-psc", .driver_data = (kernel_ulong_t)&dm644x_psc_init_data }, +#endif +#ifdef CONFIG_ARCH_DAVINCI_DM646x + { .name = "dm646x-psc", .driver_data = (kernel_ulong_t)&dm646x_psc_init_data }, +#endif + { } +}; + +static int davinci_psc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct of_device_id *of_id; + const struct davinci_psc_init_data *init_data = NULL; + struct resource *res; + void __iomem *base; + int ret; + + of_id = of_match_device(davinci_psc_of_match, dev); + if (of_id) + init_data = of_id->data; + else if (pdev->id_entry) + init_data = (void *)pdev->id_entry->driver_data; + + if (!init_data) { + dev_err(dev, "unable to find driver init data\n"); + return -EINVAL; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + ret = devm_clk_bulk_get(dev, init_data->num_parent_clks, + init_data->parent_clks); + if (ret < 0) + return ret; + + return init_data->psc_init(dev, base); +} + +static struct platform_driver davinci_psc_driver = { + .probe = davinci_psc_probe, + .driver = { + .name = "davinci-psc-clk", + .of_match_table = davinci_psc_of_match, + }, + .id_table = davinci_psc_id_table, +}; + +static int __init davinci_psc_driver_init(void) +{ + return platform_driver_register(&davinci_psc_driver); +} + +/* has to be postcore_initcall because davinci_gpio depend on PSC clocks */ +postcore_initcall(davinci_psc_driver_init); |