From patchwork Wed Dec 12 21:43:06 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Hunter, Jon" X-Patchwork-Id: 1870481 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 8C27F4006A for ; Wed, 12 Dec 2012 21:45:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755327Ab2LLVo7 (ORCPT ); Wed, 12 Dec 2012 16:44:59 -0500 Received: from devils.ext.ti.com ([198.47.26.153]:47062 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932129Ab2LLVox (ORCPT ); Wed, 12 Dec 2012 16:44:53 -0500 Received: from dlelxv30.itg.ti.com ([172.17.2.17]) by devils.ext.ti.com (8.13.7/8.13.7) with ESMTP id qBCLiXSW005556; Wed, 12 Dec 2012 15:44:33 -0600 Received: from DLEE74.ent.ti.com (dlee74.ent.ti.com [157.170.170.8]) by dlelxv30.itg.ti.com (8.13.8/8.13.8) with ESMTP id qBCLiXvT031964; Wed, 12 Dec 2012 15:44:33 -0600 Received: from dlelxv23.itg.ti.com (172.17.1.198) by DLEE74.ent.ti.com (157.170.170.8) with Microsoft SMTP Server id 14.1.323.3; Wed, 12 Dec 2012 15:44:33 -0600 Received: from legion.dal.design.ti.com (legion.dal.design.ti.com [128.247.22.53]) by dlelxv23.itg.ti.com (8.13.8/8.13.8) with ESMTP id qBCLiXf4031523; Wed, 12 Dec 2012 15:44:33 -0600 Received: from localhost (ula0741266.am.dhcp.ti.com [192.157.144.139]) by legion.dal.design.ti.com (8.11.7p1+Sun/8.11.7) with ESMTP id qBCLiWw10508; Wed, 12 Dec 2012 15:44:32 -0600 (CST) From: Jon Hunter To: Russell King , Will Deacon , Grant Likely , Rob Herring CC: device-tree , linux-omap , linux-arm , Paul Walmsley , Pratik Patel , Linus Walleij , Ming Lei , Jon Hunter Subject: [RFC 3/5] ARM: CTI: Convert CTI helpers to AMBA bus driver Date: Wed, 12 Dec 2012 15:43:06 -0600 Message-ID: <1355348588-22318-4-git-send-email-jon-hunter@ti.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1355348588-22318-1-git-send-email-jon-hunter@ti.com> References: <1355348588-22318-1-git-send-email-jon-hunter@ti.com> MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org Convert the Cross Trigger Interface (CTI) helpers in cti.h into a AMBA bus driver so that we can use device-tree to look-up the hardware specific information such as base address and interrupt number during the device probe. This also add APIs to request, cti_get() and release, cti_put(), a CTI module so that drivers can allocate a module at runtime. Currently, the driver only supports looking-up the CTI hardware information via device-tree, however, the driver could be extended to support non-device-tree configurations if needed for a particular architecture. The CTI driver only currently supports CTI modules that have a single CPU interrupt, however, could be extended in the future to support more interrupts if a device requires this. Signed-off-by: Jon Hunter --- arch/arm/include/asm/cti.h | 153 ------------------------ drivers/Kconfig | 2 + drivers/amba/Kconfig | 20 ++++ drivers/amba/Makefile | 1 + drivers/amba/cti.c | 284 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/amba/cti.h | 82 +++++++++++++ 6 files changed, 389 insertions(+), 153 deletions(-) delete mode 100644 arch/arm/include/asm/cti.h create mode 100644 drivers/amba/Kconfig create mode 100644 drivers/amba/cti.c create mode 100644 include/linux/amba/cti.h diff --git a/arch/arm/include/asm/cti.h b/arch/arm/include/asm/cti.h deleted file mode 100644 index 00add00..0000000 --- a/arch/arm/include/asm/cti.h +++ /dev/null @@ -1,153 +0,0 @@ -#ifndef __ASMARM_CTI_H -#define __ASMARM_CTI_H - -#include -#include - -/* The registers' definition is from section 3.2 of - * Embedded Cross Trigger Revision: r0p0 - */ -#define CTICONTROL 0x000 -#define CTISTATUS 0x004 -#define CTILOCK 0x008 -#define CTIPROTECTION 0x00C -#define CTIINTACK 0x010 -#define CTIAPPSET 0x014 -#define CTIAPPCLEAR 0x018 -#define CTIAPPPULSE 0x01c -#define CTIINEN 0x020 -#define CTIOUTEN 0x0A0 -#define CTITRIGINSTATUS 0x130 -#define CTITRIGOUTSTATUS 0x134 -#define CTICHINSTATUS 0x138 -#define CTICHOUTSTATUS 0x13c -#define CTIPERIPHID0 0xFE0 -#define CTIPERIPHID1 0xFE4 -#define CTIPERIPHID2 0xFE8 -#define CTIPERIPHID3 0xFEC -#define CTIPCELLID0 0xFF0 -#define CTIPCELLID1 0xFF4 -#define CTIPCELLID2 0xFF8 -#define CTIPCELLID3 0xFFC - -/** - * struct cti - cross trigger interface struct - * @base: mapped virtual address for the cti base - * @irq: irq number for the cti - * @trig_out_for_irq: triger out number which will cause - * the @irq happen - * - * cti struct used to operate cti registers. - */ -struct cti { - void __iomem *base; - int irq; - int trig_out_for_irq; -}; - -/** - * cti_init - initialize the cti instance - * @cti: cti instance - * @base: mapped virtual address for the cti base - * @irq: irq number for the cti - * @trig_out: triger out number which will cause - * the @irq happen - * - * called by machine code to pass the board dependent - * @base, @irq and @trig_out to cti. - */ -static inline void cti_init(struct cti *cti, - void __iomem *base, int irq, int trig_out) -{ - cti->base = base; - cti->irq = irq; - cti->trig_out_for_irq = trig_out; -} - -/** - * cti_map_trigger - use the @chan to map @trig_in to @trig_out - * @cti: cti instance - * @trig_in: trigger in number - * @trig_out: trigger out number - * @channel: channel number - * - * This function maps one trigger in of @trig_in to one trigger - * out of @trig_out using the channel @chan. - */ -static inline void cti_map_trigger(struct cti *cti, - int trig_in, int trig_out, int chan) -{ - void __iomem *base = cti->base; - unsigned long val; - - val = __raw_readl(base + CTIINEN + trig_in * 4); - val |= BIT(chan); - __raw_writel(val, base + CTIINEN + trig_in * 4); - - val = __raw_readl(base + CTIOUTEN + trig_out * 4); - val |= BIT(chan); - __raw_writel(val, base + CTIOUTEN + trig_out * 4); -} - -/** - * cti_enable - enable the cti module - * @cti: cti instance - * - * enable the cti module - */ -static inline void cti_enable(struct cti *cti) -{ - __raw_writel(0x1, cti->base + CTICONTROL); -} - -/** - * cti_disable - disable the cti module - * @cti: cti instance - * - * enable the cti module - */ -static inline void cti_disable(struct cti *cti) -{ - __raw_writel(0, cti->base + CTICONTROL); -} - -/** - * cti_irq_ack - clear the cti irq - * @cti: cti instance - * - * clear the cti irq - */ -static inline void cti_irq_ack(struct cti *cti) -{ - void __iomem *base = cti->base; - unsigned long val; - - val = __raw_readl(base + CTIINTACK); - val |= BIT(cti->trig_out_for_irq); - __raw_writel(val, base + CTIINTACK); -} - -/** - * cti_unlock - unlock cti module - * @cti: cti instance - * - * unlock the cti module, or else any writes to the cti - * module is not allowed. - */ -static inline void cti_unlock(struct cti *cti) -{ - coresight_unlock(cti->base); -} - -/** - * cti_lock - lock cti module - * @cti: cti instance - * - * lock the cti module, so any writes to the cti - * module will be not allowed. - */ -static inline void cti_lock(struct cti *cti) -{ - coresight_lock(cti->base); -} -#endif diff --git a/drivers/Kconfig b/drivers/Kconfig index dbdefa3..e857075 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -2,6 +2,8 @@ menu "Device Drivers" source "drivers/base/Kconfig" +source "drivers/amba/Kconfig" + source "drivers/bus/Kconfig" source "drivers/connector/Kconfig" diff --git a/drivers/amba/Kconfig b/drivers/amba/Kconfig new file mode 100644 index 0000000..b97ea23 --- /dev/null +++ b/drivers/amba/Kconfig @@ -0,0 +1,20 @@ +# +# AMBA Devices +# + +menu "AMBA devices" + +config ARM_AMBA_CTI + bool "Cross-Trigger Interface" + depends on ARM && OF + select ARM_AMBA + help + The ARM Cross Trigger Interface provides a way to route events + between processor modules. For example, debug events from one + processor can be broadcasted to other processors. The events that + can be routed between processors are specific to the device. + Currently, the driver only supports looking-up the CTI hardware + information (base address and interrupts) from device-tree (and + hence, is dependent upon CONFIG_OF). + +endmenu diff --git a/drivers/amba/Makefile b/drivers/amba/Makefile index 66e81c2..f74abe9 100644 --- a/drivers/amba/Makefile +++ b/drivers/amba/Makefile @@ -1,2 +1,3 @@ obj-$(CONFIG_ARM_AMBA) += bus.o +obj-$(CONFIG_ARM_AMBA_CTI) += cti.o obj-$(CONFIG_TEGRA_AHB) += tegra-ahb.o diff --git a/drivers/amba/cti.c b/drivers/amba/cti.c new file mode 100644 index 0000000..04debe7 --- /dev/null +++ b/drivers/amba/cti.c @@ -0,0 +1,284 @@ +/* + * ARM Cross Trigger Interface (CTI) Driver + * + * Copyright (C) 2012 Texas Instruments, Inc. + * Jon Hunter + * + * Based upon CTI Helpers by Ming Lei . + * + * 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; either version 2 of the License, or + * (at your option) any later version. + */ + +#include + +#include +#include +#include +#include +#include +#include +#include +#include + +/* The registers' definition is from section 3.2 of + * Embedded Cross Trigger Revision: r0p0 + */ +#define CTICONTROL 0x000 +#define CTISTATUS 0x004 +#define CTILOCK 0x008 +#define CTIPROTECTION 0x00C +#define CTIINTACK 0x010 +#define CTIAPPSET 0x014 +#define CTIAPPCLEAR 0x018 +#define CTIAPPPULSE 0x01c +#define CTIINEN 0x020 +#define CTIOUTEN 0x0A0 +#define CTITRIGINSTATUS 0x130 +#define CTITRIGOUTSTATUS 0x134 +#define CTICHINSTATUS 0x138 +#define CTICHOUTSTATUS 0x13c +#define CTIPERIPHID0 0xFE0 +#define CTIPERIPHID1 0xFE4 +#define CTIPERIPHID2 0xFE8 +#define CTIPERIPHID3 0xFEC +#define CTIPCELLID0 0xFF0 +#define CTIPCELLID1 0xFF4 +#define CTIPCELLID2 0xFF8 +#define CTIPCELLID3 0xFFC +#define CTI_MAX_CHANNELS 15 +#define CTI_MAX_TRIGGERS 7 + +#define cti_writel(v, c, x) (__raw_writel((v), (c)->base + (x))) +#define cti_readl(c, x) (__raw_readl((c)->base + (x))) + +static DEFINE_SPINLOCK(cti_lock); +static LIST_HEAD(cti_list); + +/** + * cti_map_trigger - use the @chan to map @trig_in to @trig_out + * @cti: CTI instance + * @trig_in: trigger in number + * @trig_out: trigger out number + * @chan: channel number + * + * Maps one trigger in of @trig_in to one trigger out of @trig_out + * using the channel @chan. The CTI module must not be enabled when + * calling this function. + */ +int cti_map_trigger(struct cti *cti, int trig_in, int trig_out, int chan) +{ + u32 v; + + if (!cti) + return -EINVAL; + + if (cti->enabled) + return -EBUSY; + + if (chan > CTI_MAX_CHANNELS) + return -EINVAL; + + if ((trig_in > CTI_MAX_TRIGGERS) || (trig_out > CTI_MAX_TRIGGERS)) + return -EINVAL; + + coresight_unlock(cti->base); + + v = cti_readl(cti, CTIINEN + trig_in * 4); + v |= BIT(chan); + cti_writel(v, cti, CTIINEN + trig_in * 4); + v = cti_readl(cti, CTIOUTEN + trig_out * 4); + v |= BIT(chan); + cti_writel(v, cti, CTIOUTEN + trig_out * 4); + cti->trig_out = trig_out; + + coresight_lock(cti->base); + + return 0; +} + +/** + * cti_enable - enable the CTI module + * @cti: CTI instance + * + * Unlocks and enables the CTI module. The CTI module cannot be + * programmed again until it has been disabled. + */ +int cti_enable(struct cti *cti) +{ + if (!cti || cti->enabled) + return -EINVAL; + + coresight_unlock(cti->base); + cti_writel(1, cti, CTICONTROL); + cti->enabled = true; + + return 0; +} + +/** + * cti_disable - disable the CTI module + * @cti: CTI instance + * + * Disables and locks the CTI module. + */ +int cti_disable(struct cti *cti) +{ + if (!cti || !cti->enabled) + return -EINVAL; + + cti_writel(0, cti, CTICONTROL); + cti->enabled = false; + coresight_lock(cti->base); + + return 0; +} + +/** + * cti_irq_ack - acknowledges the CTI trigger output + * @cti: CTI instance + * + * Acknowledges the CTI trigger output by writting to the appropriate + * bit in the CTI interrupt acknowledge register. + */ +int cti_irq_ack(struct cti *cti) +{ + u32 v; + + if (!cti || !cti->enabled) + return -EINVAL; + + v = cti_readl(cti, CTIINTACK); + v |= BIT(cti->trig_out); + cti_writel(v, cti, CTIINTACK); + + return 0; +} + +/** + * cti_get - acquire a CTI module + * @name: name of CTI instance + * + * Acquires a CTI module from a list of CTI modules by name. If the CTI + * module is already in use then return NULL, otherwise return a valid + * handle to the CTI module. + */ +struct cti *cti_get(const char *name) +{ + struct cti *cti = NULL; + unsigned long flags; + + if (!name) + return NULL; + + spin_lock_irqsave(&cti_lock, flags); + + if (list_empty(&cti_list)) + goto out; + + list_for_each_entry(cti, &cti_list, node) { + if (!strcmp(cti->name, name) && (!cti->reserved)) { + cti->reserved = true; + goto out; + } + } + +out: + spin_unlock_irqrestore(&cti_lock, flags); + + if (cti) + pm_runtime_get_sync(cti->dev); + + return cti; +} + +/** + * cti_put - release handle to CTI module + * @cti: CTI instance + * + * Releases a handle to CTI module that was previously acquired. + */ +void cti_put(struct cti *cti) +{ + if (!cti || !cti->reserved) + return; + + cti->reserved = false; + + pm_runtime_put(cti->dev); +} + +static int cti_probe(struct amba_device *dev, const struct amba_id *id) +{ + struct cti *cti; + struct device_node *np = dev->dev.of_node; + int rc; + + if (!np) { + dev_err(&dev->dev, "device-tree not found!\n"); + return -ENODEV; + } + + cti = devm_kzalloc(&dev->dev, sizeof(struct cti), GFP_KERNEL); + if (!cti) { + dev_err(&dev->dev, "memory allocation failed!\n"); + return -ENOMEM; + } + + rc = of_property_read_string_index(np, "arm,cti-name", 0, &cti->name); + if (rc) { + dev_err(&dev->dev, "no name found for CTI!\n"); + return rc; + } + + if (!dev->irq[0]) { + dev_err(&dev->dev, "no CTI interrupt found!\n"); + return -ENODEV; + } + + cti->irq = dev->irq[0]; + cti->base = of_iomap(np, 0); + if (!cti->base) { + dev_err(&dev->dev, "unable to map CTI registers!\n"); + return -ENOMEM; + } + + cti->dev = &dev->dev; + amba_set_drvdata(dev, cti); + list_add_tail(&cti->node, &cti_list); + + /* + * AMBA bus driver has already enabled RPM and incremented + * use-count, so now we can safely decrement the use-count + * and allow the CTI driver to manage RPM for the device. + */ + pm_runtime_put(&dev->dev); + + dev_info(&dev->dev, "ARM CTI driver"); + + return 0; +} + +static const struct amba_id cti_ids[] = { + { + .id = 0x003bb906, + .mask = 0x00ffffff, + }, + { 0, 0 }, +}; + +static struct amba_driver cti_driver = { + .drv = { + .name = "cti", + }, + .id_table = cti_ids, + .probe = cti_probe, +}; + +static int __init cti_init(void) +{ + return amba_driver_register(&cti_driver); +} +subsys_initcall(cti_init); diff --git a/include/linux/amba/cti.h b/include/linux/amba/cti.h new file mode 100644 index 0000000..a82ae76 --- /dev/null +++ b/include/linux/amba/cti.h @@ -0,0 +1,82 @@ +/* + * ARM Cross Trigger Interface Platform Driver + * + * Copyright (C) 2012 Texas Instruments, Inc. + * Jon Hunter + * + * 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; either version 2 of the License, or + * (at your option) any later version. + */ + +#ifndef AMBA_CTI_H +#define AMBA_CTI_H + +#include + +/** + * struct cti - Cross Trigger Interface (CTI) struct + * + * @node: Connects CTI instance to list of CTI instances + * @dev: Pointer to device structure + * @base: Mapped virtual address of the CTI module + * @name: Name associated with CTI instance + * @irq: Interrupt associated with CTI instance + * @trig_out: Trigger output associated with interrupt (@irq) + * @reserved: Used to indicate if CTI instance has been allocated + * @enabled: Used to indicate if CTI instance has been enabled + */ +struct cti { + struct list_head node; + struct device *dev; + void __iomem *base; + const char *name; + int irq; + int trig_out; + bool reserved; + bool enabled; +}; + +#ifdef CONFIG_ARM_AMBA_CTI + +int cti_map_trigger(struct cti *cti, int trig_in, int trig_out, int chan); +int cti_enable(struct cti *cti); +int cti_disable(struct cti *cti); +int cti_irq_ack(struct cti *cti); +struct cti *cti_get(const char *name); +void cti_put(struct cti *cti); + +#else + +static inline int cti_map_trigger(struct cti *cti, int trig_in, int trig_out, + int chan) +{ + return 0; +} + +static inline int cti_enable(struct cti *cti) +{ + return 0; +} + +static inline int cti_disable(struct cti *cti) +{ + return 0; +} + +static inline int cti_irq_ack(struct cti *cti) +{ + return 0; +} + +static inline struct cti *cti_get(const char *name) +{ + return NULL; +} + +static inline void cti_put(struct cti *cti) {} + +#endif /* ARM_AMBA_CTI */ + +#endif /* AMBA_CTI_H */