From: Rafael J. Wysocki Date: Wed, 6 Mar 2013 22:46:20 +0000 (+0100) Subject: ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices X-Git-Tag: v3.12-rc1~830^2~12^2~2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f58b082aed43400c03e53beacc50a9f9eb23ac91;p=kernel%2Fkernel-generic.git ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg Signed-off-by: Rafael J. Wysocki Acked-by: Mike Turquette --- diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 474fcfe..ecb743b 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -39,6 +39,7 @@ acpi-y += ec.o acpi-$(CONFIG_ACPI_DOCK) += dock.o acpi-y += pci_root.o pci_link.o pci_irq.o acpi-y += csrt.o +acpi-$(CONFIG_X86_INTEL_LPSS) += acpi_lpss.o acpi-y += acpi_platform.o acpi-y += power.o acpi-y += event.o diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c new file mode 100644 index 0000000..823df46 --- /dev/null +++ b/drivers/acpi/acpi_lpss.c @@ -0,0 +1,163 @@ +/* + * 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 "internal.h" + +ACPI_MODULE_NAME("acpi_lpss"); + +#define LPSS_CLK_OFFSET 0x800 +#define LPSS_CLK_SIZE 0x04 + +struct lpss_device_desc { + bool clk_required; + const char *clk_parent; +}; + +struct lpss_private_data { + void __iomem *mmio_base; + resource_size_t mmio_size; + struct clk *clk; + const struct lpss_device_desc *dev_desc; +}; + +static struct lpss_device_desc lpt_dev_desc = { + .clk_required = true, + .clk_parent = "lpss_clk", +}; + +static const struct acpi_device_id acpi_lpss_device_ids[] = { + /* Lynxpoint LPSS devices */ + { "INT33C0", (unsigned long)&lpt_dev_desc }, + { "INT33C1", (unsigned long)&lpt_dev_desc }, + { "INT33C2", (unsigned long)&lpt_dev_desc }, + { "INT33C3", (unsigned long)&lpt_dev_desc }, + { "INT33C4", (unsigned long)&lpt_dev_desc }, + { "INT33C5", (unsigned long)&lpt_dev_desc }, + { "INT33C6", }, + { "INT33C7", }, + + { } +}; + +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; + + if (!lpss_clk_dev) + lpt_register_clock_device(); + + if (!dev_desc->clk_parent || !pdata->mmio_base + || pdata->mmio_size < LPSS_CLK_OFFSET + LPSS_CLK_SIZE) + return -ENODATA; + + pdata->clk = clk_register_gate(NULL, dev_name(&adev->dev), + dev_desc->clk_parent, 0, + pdata->mmio_base + LPSS_CLK_OFFSET, + 0, 0, NULL); + if (IS_ERR(pdata->clk)) + return PTR_ERR(pdata->clk); + + clk_register_clkdev(pdata->clk, NULL, dev_name(&adev->dev)); + 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; + int ret; + + dev_desc = (struct lpss_device_desc *)id->driver_data; + if (!dev_desc) + return acpi_create_platform_device(adev, id); + + 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) { + pdata->mmio_size = resource_size(&rentry->res); + pdata->mmio_base = ioremap(rentry->res.start, + pdata->mmio_size); + pdata->dev_desc = dev_desc; + break; + } + + acpi_dev_free_resource_list(&resource_list); + + if (dev_desc->clk_required) { + ret = register_device_clock(adev, pdata); + if (ret) { + /* + * Skip the device, but don't terminate the namespace + * scan. + */ + ret = 0; + goto err_out; + } + } + + adev->driver_data = pdata; + ret = acpi_create_platform_device(adev, id); + if (ret > 0) + return ret; + + adev->driver_data = NULL; + + err_out: + kfree(pdata); + return ret; +} + +static struct acpi_scan_handler lpss_handler = { + .ids = acpi_lpss_device_ids, + .attach = acpi_lpss_create_device, +}; + +void __init acpi_lpss_init(void) +{ + if (!lpt_clk_init()) + acpi_scan_add_handler(&lpss_handler); +} diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c index 26fce4b..fafec5d 100644 --- a/drivers/acpi/acpi_platform.c +++ b/drivers/acpi/acpi_platform.c @@ -22,9 +22,6 @@ ACPI_MODULE_NAME("platform"); -/* Flags for acpi_create_platform_device */ -#define ACPI_PLATFORM_CLK BIT(0) - /* * The following ACPI IDs are known to be suitable for representing as * platform devices. @@ -33,33 +30,9 @@ static const struct acpi_device_id acpi_platform_device_ids[] = { { "PNP0D40" }, - /* Haswell LPSS devices */ - { "INT33C0", ACPI_PLATFORM_CLK }, - { "INT33C1", ACPI_PLATFORM_CLK }, - { "INT33C2", ACPI_PLATFORM_CLK }, - { "INT33C3", ACPI_PLATFORM_CLK }, - { "INT33C4", ACPI_PLATFORM_CLK }, - { "INT33C5", ACPI_PLATFORM_CLK }, - { "INT33C6", ACPI_PLATFORM_CLK }, - { "INT33C7", ACPI_PLATFORM_CLK }, - { } }; -static int acpi_create_platform_clks(struct acpi_device *adev) -{ - static struct platform_device *pdev; - - /* Create Lynxpoint LPSS clocks */ - if (!pdev && !strncmp(acpi_device_hid(adev), "INT33C", 6)) { - pdev = platform_device_register_simple("clk-lpt", -1, NULL, 0); - if (IS_ERR(pdev)) - return PTR_ERR(pdev); - } - - return 0; -} - /** * acpi_create_platform_device - Create platform device for ACPI device node * @adev: ACPI device node to create a platform device for. @@ -71,10 +44,9 @@ static int acpi_create_platform_clks(struct acpi_device *adev) * * Name of the platform device will be the same as @adev's. */ -static int acpi_create_platform_device(struct acpi_device *adev, - const struct acpi_device_id *id) +int acpi_create_platform_device(struct acpi_device *adev, + const struct acpi_device_id *id) { - unsigned long flags = id->driver_data; struct platform_device *pdev = NULL; struct acpi_device *acpi_parent; struct platform_device_info pdevinfo; @@ -83,14 +55,6 @@ static int acpi_create_platform_device(struct acpi_device *adev, struct resource *resources; int count; - if (flags & ACPI_PLATFORM_CLK) { - int ret = acpi_create_platform_clks(adev); - if (ret) { - dev_err(&adev->dev, "failed to create clocks\n"); - return ret; - } - } - /* If the ACPI node already has a physical device attached, skip it. */ if (adev->physical_node_count) return 0; diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 3c94a73..e227819 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -48,6 +48,11 @@ int acpi_debugfs_init(void); #else static inline void acpi_debugfs_init(void) { return; } #endif +#ifdef CONFIG_X86_INTEL_LPSS +void acpi_lpss_init(void); +#else +static inline void acpi_lpss_init(void) {} +#endif /* -------------------------------------------------------------------------- Device Node Initialization / Removal @@ -131,4 +136,7 @@ static inline void suspend_nvs_restore(void) {} -------------------------------------------------------------------------- */ struct platform_device; +int acpi_create_platform_device(struct acpi_device *adev, + const struct acpi_device_id *id); + #endif /* _ACPI_INTERNAL_H_ */ diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 5e7e991..433a4e1 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1788,6 +1788,7 @@ int __init acpi_scan_init(void) acpi_pci_root_init(); acpi_pci_link_init(); acpi_platform_init(); + acpi_lpss_init(); acpi_csrt_init(); acpi_container_init(); acpi_pci_slot_init(); diff --git a/drivers/clk/x86/Makefile b/drivers/clk/x86/Makefile index f9ba4fa..0478138 100644 --- a/drivers/clk/x86/Makefile +++ b/drivers/clk/x86/Makefile @@ -1,2 +1,2 @@ -clk-x86-lpss-objs := clk-lpss.o clk-lpt.o +clk-x86-lpss-objs := clk-lpt.o obj-$(CONFIG_X86_INTEL_LPSS) += clk-x86-lpss.o diff --git a/drivers/clk/x86/clk-lpss.c b/drivers/clk/x86/clk-lpss.c deleted file mode 100644 index b5e229f..0000000 --- a/drivers/clk/x86/clk-lpss.c +++ /dev/null @@ -1,99 +0,0 @@ -/* - * Intel Low Power Subsystem clocks. - * - * Copyright (C) 2013, Intel Corporation - * Authors: Mika Westerberg - * Heikki Krogerus - * - * 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 - -static int clk_lpss_is_mmio_resource(struct acpi_resource *res, void *data) -{ - struct resource r; - return !acpi_dev_resource_memory(res, &r); -} - -static acpi_status clk_lpss_find_mmio(acpi_handle handle, u32 level, - void *data, void **retval) -{ - struct resource_list_entry *rentry; - struct list_head resource_list; - struct acpi_device *adev; - const char *uid = data; - int ret; - - if (acpi_bus_get_device(handle, &adev)) - return AE_OK; - - if (uid) { - if (!adev->pnp.unique_id) - return AE_OK; - if (strcmp(uid, adev->pnp.unique_id)) - return AE_OK; - } - - INIT_LIST_HEAD(&resource_list); - ret = acpi_dev_get_resources(adev, &resource_list, - clk_lpss_is_mmio_resource, NULL); - if (ret < 0) - return AE_NO_MEMORY; - - list_for_each_entry(rentry, &resource_list, node) - if (resource_type(&rentry->res) == IORESOURCE_MEM) { - *(struct resource *)retval = rentry->res; - break; - } - - acpi_dev_free_resource_list(&resource_list); - return AE_OK; -} - -/** - * clk_register_lpss_gate - register LPSS clock gate - * @name: name of this clock gate - * @parent_name: parent clock name - * @hid: ACPI _HID of the device - * @uid: ACPI _UID of the device (optional) - * @offset: LPSS PRV_CLOCK_PARAMS offset - * - * Creates and registers LPSS clock gate. - */ -struct clk *clk_register_lpss_gate(const char *name, const char *parent_name, - const char *hid, const char *uid, - unsigned offset) -{ - struct resource res = { }; - void __iomem *mmio_base; - acpi_status status; - struct clk *clk; - - /* - * First try to look the device and its mmio resource from the - * ACPI namespace. - */ - status = acpi_get_devices(hid, clk_lpss_find_mmio, (void *)uid, - (void **)&res); - if (ACPI_FAILURE(status) || !res.start) - return ERR_PTR(-ENODEV); - - mmio_base = ioremap(res.start, resource_size(&res)); - if (!mmio_base) - return ERR_PTR(-ENOMEM); - - clk = clk_register_gate(NULL, name, parent_name, 0, mmio_base + offset, - 0, 0, NULL); - if (IS_ERR(clk)) - iounmap(mmio_base); - - return clk; -} diff --git a/drivers/clk/x86/clk-lpss.h b/drivers/clk/x86/clk-lpss.h deleted file mode 100644 index e9460f4..0000000 --- a/drivers/clk/x86/clk-lpss.h +++ /dev/null @@ -1,36 +0,0 @@ -/* - * Intel Low Power Subsystem clock. - * - * Copyright (C) 2013, Intel Corporation - * Authors: Mika Westerberg - * Heikki Krogerus - * - * 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. - */ - -#ifndef __CLK_LPSS_H -#define __CLK_LPSS_H - -#include -#include -#include - -#ifdef CONFIG_ACPI -extern struct clk *clk_register_lpss_gate(const char *name, - const char *parent_name, - const char *hid, const char *uid, - unsigned offset); -#else -static inline struct clk *clk_register_lpss_gate(const char *name, - const char *parent_name, - const char *hid, - const char *uid, - unsigned offset) -{ - return ERR_PTR(-ENODEV); -} -#endif - -#endif /* __CLK_LPSS_H */ diff --git a/drivers/clk/x86/clk-lpt.c b/drivers/clk/x86/clk-lpt.c index 81298ae..5cf4f46 100644 --- a/drivers/clk/x86/clk-lpt.c +++ b/drivers/clk/x86/clk-lpt.c @@ -10,7 +10,6 @@ * published by the Free Software Foundation. */ -#include #include #include #include @@ -18,8 +17,6 @@ #include #include -#include "clk-lpss.h" - #define PRV_CLOCK_PARAMS 0x800 static int lpt_clk_probe(struct platform_device *pdev) @@ -34,40 +31,6 @@ static int lpt_clk_probe(struct platform_device *pdev) /* Shared DMA clock */ clk_register_clkdev(clk, "hclk", "INTL9C60.0.auto"); - - /* SPI clocks */ - clk = clk_register_lpss_gate("spi0_clk", "lpss_clk", "INT33C0", NULL, - PRV_CLOCK_PARAMS); - if (!IS_ERR(clk)) - clk_register_clkdev(clk, NULL, "INT33C0:00"); - - clk = clk_register_lpss_gate("spi1_clk", "lpss_clk", "INT33C1", NULL, - PRV_CLOCK_PARAMS); - if (!IS_ERR(clk)) - clk_register_clkdev(clk, NULL, "INT33C1:00"); - - /* I2C clocks */ - clk = clk_register_lpss_gate("i2c0_clk", "lpss_clk", "INT33C2", NULL, - PRV_CLOCK_PARAMS); - if (!IS_ERR(clk)) - clk_register_clkdev(clk, NULL, "INT33C2:00"); - - clk = clk_register_lpss_gate("i2c1_clk", "lpss_clk", "INT33C3", NULL, - PRV_CLOCK_PARAMS); - if (!IS_ERR(clk)) - clk_register_clkdev(clk, NULL, "INT33C3:00"); - - /* UART clocks */ - clk = clk_register_lpss_gate("uart0_clk", "lpss_clk", "INT33C4", NULL, - PRV_CLOCK_PARAMS); - if (!IS_ERR(clk)) - clk_register_clkdev(clk, NULL, "INT33C4:00"); - - clk = clk_register_lpss_gate("uart1_clk", "lpss_clk", "INT33C5", NULL, - PRV_CLOCK_PARAMS); - if (!IS_ERR(clk)) - clk_register_clkdev(clk, NULL, "INT33C5:00"); - return 0; } @@ -79,8 +42,7 @@ static struct platform_driver lpt_clk_driver = { .probe = lpt_clk_probe, }; -static int __init lpt_clk_init(void) +int __init lpt_clk_init(void) { return platform_driver_register(&lpt_clk_driver); } -arch_initcall(lpt_clk_init); diff --git a/include/linux/platform_data/clk-lpss.h b/include/linux/platform_data/clk-lpss.h new file mode 100644 index 0000000..528e73c --- /dev/null +++ b/include/linux/platform_data/clk-lpss.h @@ -0,0 +1,18 @@ +/* + * Intel Low Power Subsystem clocks. + * + * 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. + */ + +#ifndef __CLK_LPSS_H +#define __CLK_LPSS_H + +extern int lpt_clk_init(void); + +#endif /* __CLK_LPSS_H */