/* * ACPI support for Intel Lynxpoint LPSS. * * Copyright (C) 2013, Intel Corporation * Authors: Mika Westerberg * Rafael J. Wysocki * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include "internal.h" ACPI_MODULE_NAME("acpi_lpss"); #define LPSS_CLK_SIZE 0x04 #define LPSS_LTR_SIZE 0x18 /* Offsets relative to LPSS_PRIVATE_OFFSET */ #define LPSS_CLK_DIVIDER_DEF_MASK (BIT(1) | BIT(16)) #define LPSS_GENERAL 0x08 #define LPSS_GENERAL_LTR_MODE_SW BIT(2) #define LPSS_GENERAL_UART_RTS_OVRD BIT(3) #define LPSS_SW_LTR 0x10 #define LPSS_AUTO_LTR 0x14 #define LPSS_LTR_SNOOP_REQ BIT(15) #define LPSS_LTR_SNOOP_MASK 0x0000FFFF #define LPSS_LTR_SNOOP_LAT_1US 0x800 #define LPSS_LTR_SNOOP_LAT_32US 0xC00 #define LPSS_LTR_SNOOP_LAT_SHIFT 5 #define LPSS_LTR_SNOOP_LAT_CUTOFF 3000 #define LPSS_LTR_MAX_VAL 0x3FF #define LPSS_TX_INT 0x20 #define LPSS_TX_INT_MASK BIT(1) #define LPSS_PRV_REG_COUNT 9 struct lpss_shared_clock { const char *name; unsigned long rate; struct clk *clk; }; struct lpss_private_data; struct lpss_device_desc { bool clk_required; const char *clkdev_name; bool ltr_required; unsigned int prv_offset; size_t prv_size_override; bool clk_divider; bool clk_gate; bool save_ctx; struct lpss_shared_clock *shared_clock; void (*setup)(struct lpss_private_data *pdata); }; static struct lpss_device_desc lpss_dma_desc = { .clk_required = true, .clkdev_name = "hclk", }; struct lpss_private_data { void __iomem *mmio_base; resource_size_t mmio_size; struct clk *clk; const struct lpss_device_desc *dev_desc; u32 prv_reg_ctx[LPSS_PRV_REG_COUNT]; }; static void lpss_uart_setup(struct lpss_private_data *pdata) { unsigned int offset; u32 reg; offset = pdata->dev_desc->prv_offset + LPSS_TX_INT; reg = readl(pdata->mmio_base + offset); writel(reg | LPSS_TX_INT_MASK, pdata->mmio_base + offset); offset = pdata->dev_desc->prv_offset + LPSS_GENERAL; reg = readl(pdata->mmio_base + offset); writel(reg | LPSS_GENERAL_UART_RTS_OVRD, pdata->mmio_base + offset); } static struct lpss_device_desc lpt_dev_desc = { .clk_required = true, .prv_offset = 0x800, .ltr_required = true, .clk_divider = true, .clk_gate = true, }; static struct lpss_device_desc lpt_i2c_dev_desc = { .clk_required = true, .prv_offset = 0x800, .ltr_required = true, .clk_gate = true, }; static struct lpss_device_desc lpt_uart_dev_desc = { .clk_required = true, .prv_offset = 0x800, .ltr_required = true, .clk_divider = true, .clk_gate = true, .setup = lpss_uart_setup, }; static struct lpss_device_desc lpt_sdio_dev_desc = { .prv_offset = 0x1000, .prv_size_override = 0x1018, .ltr_required = true, }; static struct lpss_shared_clock pwm_clock = { .name = "pwm_clk", .rate = 25000000, }; static struct lpss_device_desc byt_pwm_dev_desc = { .clk_required = true, .save_ctx = true, .shared_clock = &pwm_clock, }; static struct lpss_device_desc byt_uart_dev_desc = { .clk_required = true, .prv_offset = 0x800, .clk_divider = true, .clk_gate = true, .save_ctx = true, .setup = lpss_uart_setup, }; static struct lpss_device_desc byt_spi_dev_desc = { .clk_required = true, .prv_offset = 0x400, .clk_divider = true, .clk_gate = true, .save_ctx = true, }; static struct lpss_device_desc byt_sdio_dev_desc = { .clk_required = true, }; static struct lpss_shared_clock i2c_clock = { .name = "i2c_clk", .rate = 100000000, }; static struct lpss_device_desc byt_i2c_dev_desc = { .clk_required = true, .prv_offset = 0x800, .save_ctx = true, .shared_clock = &i2c_clock, }; static const struct acpi_device_id acpi_lpss_device_ids[] = { /* Generic LPSS devices */ { "INTL9C60", (unsigned long)&lpss_dma_desc }, /* Lynxpoint LPSS devices */ { "INT33C0", (unsigned long)&lpt_dev_desc }, { "INT33C1", (unsigned long)&lpt_dev_desc }, { "INT33C2", (unsigned long)&lpt_i2c_dev_desc }, { "INT33C3", (unsigned long)&lpt_i2c_dev_desc }, { "INT33C4", (unsigned long)&lpt_uart_dev_desc }, { "INT33C5", (unsigned long)&lpt_uart_dev_desc }, { "INT33C6", (unsigned long)&lpt_sdio_dev_desc }, { "INT33C7", }, /* BayTrail LPSS devices */ { "80860F09", (unsigned long)&byt_pwm_dev_desc }, { "80860F0A", (unsigned long)&byt_uart_dev_desc }, { "80860F0E", (unsigned long)&byt_spi_dev_desc }, { "80860F14", (unsigned long)&byt_sdio_dev_desc }, { "80860F41", (unsigned long)&byt_i2c_dev_desc }, { "INT33B2", }, { "INT3430", (unsigned long)&lpt_dev_desc }, { "INT3431", (unsigned long)&lpt_dev_desc }, { "INT3432", (unsigned long)&lpt_i2c_dev_desc }, { "INT3433", (unsigned long)&lpt_i2c_dev_desc }, { "INT3434", (unsigned long)&lpt_uart_dev_desc }, { "INT3435", (unsigned long)&lpt_uart_dev_desc }, { "INT3436", (unsigned long)&lpt_sdio_dev_desc }, { "INT3437", }, { } }; static int is_memory(struct acpi_resource *res, void *not_used) { struct resource r; return !acpi_dev_resource_memory(res, &r); } /* LPSS main clock device. */ static struct platform_device *lpss_clk_dev; static inline void lpt_register_clock_device(void) { lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0); } static int register_device_clock(struct acpi_device *adev, struct lpss_private_data *pdata) { const struct lpss_device_desc *dev_desc = pdata->dev_desc; struct lpss_shared_clock *shared_clock = dev_desc->shared_clock; const char *devname = dev_name(&adev->dev); struct clk *clk = ERR_PTR(-ENODEV); struct lpss_clk_data *clk_data; const char *parent, *clk_name; void __iomem *prv_base; if (!lpss_clk_dev) lpt_register_clock_device(); clk_data = platform_get_drvdata(lpss_clk_dev); if (!clk_data) return -ENODEV; if (dev_desc->clkdev_name) { clk_register_clkdev(clk_data->clk, dev_desc->clkdev_name, devname); return 0; } if (!pdata->mmio_base || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE) return -ENODATA; parent = clk_data->name; prv_base = pdata->mmio_base + dev_desc->prv_offset; if (shared_clock) { clk = shared_clock->clk; if (!clk) { clk = clk_register_fixed_rate(NULL, shared_clock->name, "lpss_clk", 0, shared_clock->rate); shared_clock->clk = clk; } parent = shared_clock->name; } if (dev_desc->clk_gate) { clk = clk_register_gate(NULL, devname, parent, 0, prv_base, 0, 0, NULL); parent = devname; } if (dev_desc->clk_divider) { /* Prevent division by zero */ if (!readl(prv_base)) writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base); clk_name = kasprintf(GFP_KERNEL, "%s-div", devname); if (!clk_name) return -ENOMEM; clk = clk_register_fractional_divider(NULL, clk_name, parent, 0, prv_base, 1, 15, 16, 15, 0, NULL); parent = clk_name; clk_name = kasprintf(GFP_KERNEL, "%s-update", devname); if (!clk_name) { kfree(parent); return -ENOMEM; } clk = clk_register_gate(NULL, clk_name, parent, CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE, prv_base, 31, 0, NULL); kfree(parent); kfree(clk_name); } if (IS_ERR(clk)) return PTR_ERR(clk); pdata->clk = clk; clk_register_clkdev(clk, NULL, devname); return 0; } static int acpi_lpss_create_device(struct acpi_device *adev, const struct acpi_device_id *id) { struct lpss_device_desc *dev_desc; struct lpss_private_data *pdata; struct resource_list_entry *rentry; struct list_head resource_list; struct platform_device *pdev; int ret; dev_desc = (struct lpss_device_desc *)id->driver_data; if (!dev_desc) { pdev = acpi_create_platform_device(adev); return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1; } pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); if (!pdata) return -ENOMEM; INIT_LIST_HEAD(&resource_list); ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL); if (ret < 0) goto err_out; list_for_each_entry(rentry, &resource_list, node) if (resource_type(&rentry->res) == IORESOURCE_MEM) { if (dev_desc->prv_size_override) pdata->mmio_size = dev_desc->prv_size_override; else pdata->mmio_size = resource_size(&rentry->res); pdata->mmio_base = ioremap(rentry->res.start, pdata->mmio_size); break; } acpi_dev_free_resource_list(&resource_list); pdata->dev_desc = dev_desc; if (dev_desc->clk_required) { ret = register_device_clock(adev, pdata); if (ret) { /* Skip the device, but continue the namespace scan. */ ret = 0; goto err_out; } } /* * This works around a known issue in ACPI tables where LPSS devices * have _PS0 and _PS3 without _PSC (and no power resources), so * acpi_bus_init_power() will assume that the BIOS has put them into D0. */ ret = acpi_device_fix_up_power(adev); if (ret) { /* Skip the device, but continue the namespace scan. */ ret = 0; goto err_out; } if (dev_desc->setup) dev_desc->setup(pdata); adev->driver_data = pdata; pdev = acpi_create_platform_device(adev); if (!IS_ERR_OR_NULL(pdev)) { device_enable_async_suspend(&pdev->dev); return 1; } ret = PTR_ERR(pdev); adev->driver_data = NULL; err_out: kfree(pdata); return ret; } static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg) { return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg); } static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata, unsigned int reg) { writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg); } static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val) { struct acpi_device *adev; struct lpss_private_data *pdata; unsigned long flags; int ret; ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev); if (WARN_ON(ret)) return ret; spin_lock_irqsave(&dev->power.lock, flags); if (pm_runtime_suspended(dev)) { ret = -EAGAIN; goto out; } pdata = acpi_driver_data(adev); if (WARN_ON(!pdata || !pdata->mmio_base)) { ret = -ENODEV; goto out; } *val = __lpss_reg_read(pdata, reg); out: spin_unlock_irqrestore(&dev->power.lock, flags); return ret; } static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr, char *buf) { u32 ltr_value = 0; unsigned int reg; int ret; reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR; ret = lpss_reg_read(dev, reg, <r_value); if (ret) return ret; return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value); } static ssize_t lpss_ltr_mode_show(struct device *dev, struct device_attribute *attr, char *buf) { u32 ltr_mode = 0; char *outstr; int ret; ret = lpss_reg_read(dev, LPSS_GENERAL, <r_mode); if (ret) return ret; outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto"; return sprintf(buf, "%s\n", outstr); } static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL); static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL); static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL); static struct attribute *lpss_attrs[] = { &dev_attr_auto_ltr.attr, &dev_attr_sw_ltr.attr, &dev_attr_ltr_mode.attr, NULL, }; static struct attribute_group lpss_attr_group = { .attrs = lpss_attrs, .name = "lpss_ltr", }; static void acpi_lpss_set_ltr(struct device *dev, s32 val) { struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); u32 ltr_mode, ltr_val; ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL); if (val < 0) { if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) { ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW; __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL); } return; } ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK; if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) { ltr_val |= LPSS_LTR_SNOOP_LAT_32US; val = LPSS_LTR_MAX_VAL; } else if (val > LPSS_LTR_MAX_VAL) { ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ; val >>= LPSS_LTR_SNOOP_LAT_SHIFT; } else { ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ; } ltr_val |= val; __lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR); if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) { ltr_mode |= LPSS_GENERAL_LTR_MODE_SW; __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL); } } #ifdef CONFIG_PM /** * acpi_lpss_save_ctx() - Save the private registers of LPSS device * @dev: LPSS device * * Most LPSS devices have private registers which may loose their context when * the device is powered down. acpi_lpss_save_ctx() saves those registers into * prv_reg_ctx array. */ static void acpi_lpss_save_ctx(struct device *dev) { struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); unsigned int i; for (i = 0; i < LPSS_PRV_REG_COUNT; i++) { unsigned long offset = i * sizeof(u32); pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset); dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n", pdata->prv_reg_ctx[i], offset); } } /** * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device * @dev: LPSS device * * Restores the registers that were previously stored with acpi_lpss_save_ctx(). */ static void acpi_lpss_restore_ctx(struct device *dev) { struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); unsigned int i; /* * The following delay is needed or the subsequent write operations may * fail. The LPSS devices are actually PCI devices and the PCI spec * expects 10ms delay before the device can be accessed after D3 to D0 * transition. */ msleep(10); for (i = 0; i < LPSS_PRV_REG_COUNT; i++) { unsigned long offset = i * sizeof(u32); __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset); dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n", pdata->prv_reg_ctx[i], offset); } } #ifdef CONFIG_PM_SLEEP static int acpi_lpss_suspend_late(struct device *dev) { int ret = pm_generic_suspend_late(dev); if (ret) return ret; acpi_lpss_save_ctx(dev); return acpi_dev_suspend_late(dev); } static int acpi_lpss_restore_early(struct device *dev) { int ret = acpi_dev_resume_early(dev); if (ret) return ret; acpi_lpss_restore_ctx(dev); return pm_generic_resume_early(dev); } #endif /* CONFIG_PM_SLEEP */ #ifdef CONFIG_PM_RUNTIME static int acpi_lpss_runtime_suspend(struct device *dev) { int ret = pm_generic_runtime_suspend(dev); if (ret) return ret; acpi_lpss_save_ctx(dev); return acpi_dev_runtime_suspend(dev); } static int acpi_lpss_runtime_resume(struct device *dev) { int ret = acpi_dev_runtime_resume(dev); if (ret) return ret; acpi_lpss_restore_ctx(dev); return pm_generic_runtime_resume(dev); } #endif /* CONFIG_PM_RUNTIME */ #endif /* CONFIG_PM */ static struct dev_pm_domain acpi_lpss_pm_domain = { .ops = { #ifdef CONFIG_PM_SLEEP .suspend_late = acpi_lpss_suspend_late, .restore_early = acpi_lpss_restore_early, .prepare = acpi_subsys_prepare, .complete = acpi_subsys_complete, .suspend = acpi_subsys_suspend, .resume_early = acpi_subsys_resume_early, .freeze = acpi_subsys_freeze, .poweroff = acpi_subsys_suspend, .poweroff_late = acpi_subsys_suspend_late, #endif #ifdef CONFIG_PM_RUNTIME .runtime_suspend = acpi_lpss_runtime_suspend, .runtime_resume = acpi_lpss_runtime_resume, #endif }, }; static int acpi_lpss_platform_notify(struct notifier_block *nb, unsigned long action, void *data) { struct platform_device *pdev = to_platform_device(data); struct lpss_private_data *pdata; struct acpi_device *adev; const struct acpi_device_id *id; id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev); if (!id || !id->driver_data) return 0; if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev)) return 0; pdata = acpi_driver_data(adev); if (!pdata || !pdata->mmio_base) return 0; if (pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) { dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n"); return 0; } switch (action) { case BUS_NOTIFY_BOUND_DRIVER: if (pdata->dev_desc->save_ctx) pdev->dev.pm_domain = &acpi_lpss_pm_domain; break; case BUS_NOTIFY_UNBOUND_DRIVER: if (pdata->dev_desc->save_ctx) pdev->dev.pm_domain = NULL; break; case BUS_NOTIFY_ADD_DEVICE: if (pdata->dev_desc->ltr_required) return sysfs_create_group(&pdev->dev.kobj, &lpss_attr_group); case BUS_NOTIFY_DEL_DEVICE: if (pdata->dev_desc->ltr_required) sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group); default: break; } return 0; } static struct notifier_block acpi_lpss_nb = { .notifier_call = acpi_lpss_platform_notify, }; static void acpi_lpss_bind(struct device *dev) { struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); if (!pdata || !pdata->mmio_base || !pdata->dev_desc->ltr_required) return; if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) dev->power.set_latency_tolerance = acpi_lpss_set_ltr; else dev_err(dev, "MMIO size insufficient to access LTR\n"); } static void acpi_lpss_unbind(struct device *dev) { dev->power.set_latency_tolerance = NULL; } static struct acpi_scan_handler lpss_handler = { .ids = acpi_lpss_device_ids, .attach = acpi_lpss_create_device, .bind = acpi_lpss_bind, .unbind = acpi_lpss_unbind, }; void __init acpi_lpss_init(void) { if (!lpt_clk_init()) { bus_register_notifier(&platform_bus_type, &acpi_lpss_nb); acpi_scan_add_handler(&lpss_handler); } }