Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966847Ab3HHWlh (ORCPT ); Thu, 8 Aug 2013 18:41:37 -0400 Received: from mail-bk0-f54.google.com ([209.85.214.54]:41585 "EHLO mail-bk0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966781Ab3HHWlf (ORCPT ); Thu, 8 Aug 2013 18:41:35 -0400 From: Tomasz Figa To: Cho KyongHo Cc: "'Linux ARM Kernel'" , "'Linux IOMMU'" , "'Linux Kernel'" , "'Linux Samsung SOC'" , devicetree@vger.kernel.org, "'Joerg Roedel'" , "'Kukjin Kim'" , "'Prathyush'" , "'Rahul Sharma'" , "'Subash Patel'" , "'Grant Grundler'" , "'Antonios Motakis'" , kvmarm@lists.cs.columbia.edu, "'Sachin Kamat'" Subject: Re: [PATCH v9 07/16] iommu/exynos: support for device tree Date: Fri, 09 Aug 2013 00:41:25 +0200 Message-ID: <5396565.vjlSOm37Vf@flatron> User-Agent: KMail/4.10.5 (Linux/3.10.4-gentoo; KDE/4.10.5; x86_64; ; ) In-Reply-To: <002b01ce941b$160a88a0$421f99e0$@samsung.com> References: <002b01ce941b$160a88a0$421f99e0$@samsung.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12593 Lines: 434 Hi KyongHo, On Thursday 08 of August 2013 18:38:49 Cho KyongHo wrote: > This commit adds device tree support for System MMU. > This also include the following changes and enhancements: > > * use managed device helper functions. > Simplyfies System MMU device driver. > > * use only a single clock descriptor. > System MMU device descriptor is seperate if it is imposible to make > a single clock descriptor to make a device descriptor for a group of > System MMUs. > > * removed dbgname member from sysmmu_drvdata structure. > debugging kernel message for a System MMU is distinguisheable with the > name of device descroptors. Please put all these three changes in separate patches. This patch is hard to review with all the changes mixed together... In addition, I believe this is the patch that should be adding device tree binding documentation, not the 6/16 one, as this is where actually support for this binding gets added to the kernel. > Signed-off-by: Cho KyongHo > --- > drivers/iommu/Kconfig | 5 +- > drivers/iommu/exynos-iommu.c | 186 > ++++++++++++++++------------------------- 2 files changed, 75 > insertions(+), 116 deletions(-) > > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > index 820d85c..9ad45f1 100644 > --- a/drivers/iommu/Kconfig > +++ b/drivers/iommu/Kconfig > @@ -168,16 +168,15 @@ config TEGRA_IOMMU_SMMU > > config EXYNOS_IOMMU > bool "Exynos IOMMU Support" > - depends on ARCH_EXYNOS && EXYNOS_DEV_SYSMMU > + depends on ARCH_EXYNOS > select IOMMU_API > + default n > help > Support for the IOMMU(System MMU) of Samsung Exynos application > processor family. This enables H/W multimedia accellerators to see > non-linear physical memory chunks as a linear memory in their > address spaces > > - If unsure, say N here. > - > config EXYNOS_IOMMU_DEBUG > bool "Debugging log for Exynos IOMMU" > depends on EXYNOS_IOMMU > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c > index a318049..0ee73e8 100644 > --- a/drivers/iommu/exynos-iommu.c > +++ b/drivers/iommu/exynos-iommu.c > @@ -26,6 +26,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -170,15 +171,14 @@ struct sysmmu_drvdata { > struct list_head node; /* entry of exynos_iommu_domain.clients */ > struct device *sysmmu; /* System MMU's device descriptor */ > struct device *dev; /* Owner of system MMU */ > - char *dbgname; > int nsfrs; > - void __iomem **sfrbases; > - struct clk *clk[2]; > + struct clk *clk; > int activations; > rwlock_t lock; > struct iommu_domain *domain; > sysmmu_fault_handler_t fault_handler; > unsigned long pgtable; > + void __iomem *sfrbases[0]; > }; > > static bool set_sysmmu_active(struct sysmmu_drvdata *data) > @@ -385,8 +385,8 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void > *dev_id) if (!ret && (itype != SYSMMU_FAULT_UNKNOWN)) > __raw_writel(1 << itype, data->sfrbases[i] + REG_INT_CLEAR); > else > - dev_dbg(data->sysmmu, "(%s) %s is not handled.\n", > - data->dbgname, sysmmu_fault_name[itype]); > + dev_dbg(data->sysmmu, "%s is not handled.\n", > + sysmmu_fault_name[itype]); > > if (itype != SYSMMU_FAULT_UNKNOWN) > sysmmu_unblock(data->sfrbases[i]); > @@ -410,10 +410,8 @@ static bool __exynos_sysmmu_disable(struct > sysmmu_drvdata *data) for (i = 0; i < data->nsfrs; i++) > __raw_writel(CTRL_DISABLE, data->sfrbases[i] + REG_MMU_CTRL); > > - if (data->clk[1]) > - clk_disable(data->clk[1]); > - if (data->clk[0]) > - clk_disable(data->clk[0]); > + if (data->clk) > + clk_disable(data->clk); > > disabled = true; > data->pgtable = 0; > @@ -422,10 +420,10 @@ finish: > write_unlock_irqrestore(&data->lock, flags); > > if (disabled) > - dev_dbg(data->sysmmu, "(%s) Disabled\n", data->dbgname); > + dev_dbg(data->sysmmu, "Disabled\n"); > else > - dev_dbg(data->sysmmu, "(%s) %d times left to be disabled\n", > - data->dbgname, data->activations); > + dev_dbg(data->sysmmu, "%d times left to be disabled\n", > + data->activations); > > return disabled; > } > @@ -452,14 +450,12 @@ static int __exynos_sysmmu_enable(struct > sysmmu_drvdata *data, ret = 1; > } > > - dev_dbg(data->sysmmu, "(%s) Already enabled\n", data- >dbgname); > + dev_dbg(data->sysmmu, "Already enabled\n"); > goto finish; > } > > - if (data->clk[0]) > - clk_enable(data->clk[0]); > - if (data->clk[1]) > - clk_enable(data->clk[1]); > + if (data->clk) > + clk_enable(data->clk); > > data->pgtable = pgtable; > > @@ -479,7 +475,7 @@ static int __exynos_sysmmu_enable(struct > sysmmu_drvdata *data, > > data->domain = domain; > > - dev_dbg(data->sysmmu, "(%s) Enabled\n", data->dbgname); > + dev_dbg(data->sysmmu, "Enabled\n"); > finish: > write_unlock_irqrestore(&data->lock, flags); > > @@ -495,7 +491,7 @@ int exynos_sysmmu_enable(struct device *dev, > unsigned long pgtable) > > ret = pm_runtime_get_sync(data->sysmmu); > if (ret < 0) { > - dev_dbg(data->sysmmu, "(%s) Failed to enable\n", data- >dbgname); > + dev_dbg(data->sysmmu, "Failed to enable\n"); > return ret; > } > > @@ -503,8 +499,8 @@ int exynos_sysmmu_enable(struct device *dev, > unsigned long pgtable) if (WARN_ON(ret < 0)) { > pm_runtime_put(data->sysmmu); > dev_err(data->sysmmu, > - "(%s) Already enabled with page table %#lx\n", > - data->dbgname, data->pgtable); > + "Already enabled with page table %#lx\n", > + data->pgtable); > } else { > data->dev = dev; > } > @@ -540,9 +536,7 @@ static void sysmmu_tlb_invalidate_entry(struct > device *dev, unsigned long iova) } > } > } else { > - dev_dbg(data->sysmmu, > - "(%s) Disabled. Skipping invalidating TLB.\n", > - data->dbgname); > + dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n"); > } > > read_unlock_irqrestore(&data->lock, flags); > @@ -564,141 +558,107 @@ void exynos_sysmmu_tlb_invalidate(struct device > *dev) } > } > } else { > - dev_dbg(data->sysmmu, > - "(%s) Disabled. Skipping invalidating TLB.\n", > - data->dbgname); > + dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n"); > } > > read_unlock_irqrestore(&data->lock, flags); > } > > -static int exynos_sysmmu_probe(struct platform_device *pdev) > +static int __init exynos_sysmmu_probe(struct platform_device *pdev) > { > int i, ret; > - struct device *dev; > + struct device *dev = &pdev->dev; > struct sysmmu_drvdata *data; > > - dev = &pdev->dev; > - > - data = kzalloc(sizeof(*data), GFP_KERNEL); > - if (!data) { > - dev_dbg(dev, "Not enough memory\n"); > - ret = -ENOMEM; > - goto err_alloc; > + if (pdev->num_resources == 0) { > + dev_err(dev, "No System MMU resource defined\n"); > + return -ENODEV; > } > > - ret = dev_set_drvdata(dev, data); > - if (ret) { > - dev_dbg(dev, "Unabled to initialize driver data\n"); > - goto err_init; > + data = devm_kzalloc(dev, > + sizeof(*data) + > + sizeof(*data->sfrbases) * (pdev->num_resources / 2), > + GFP_KERNEL); > + if (!data) { > + dev_err(dev, "Not enough memory for initialization\n"); nit: This message is not necessary, as kmalloc() already prints a message if allocation error occurs. > + return -ENOMEM; > } > > data->nsfrs = pdev->num_resources / 2; As Marek and Bart already mentioned before, please (oh please, really please) finally remove this brokenness from this driver. A device driver should not do this kind of abstraction, emulating one instance of particular IP from multiple instances. This is a task for the IOMMU core and this is already supported by IOMMU domains, which is the right way to achieve a single virtual address space for multiple IOMMUs. > - data->sfrbases = kmalloc(sizeof(*data->sfrbases) * data->nsfrs, > - GFP_KERNEL); > - if (data->sfrbases == NULL) { > - dev_dbg(dev, "Not enough memory\n"); > - ret = -ENOMEM; > - goto err_init; > - } > > for (i = 0; i < data->nsfrs; i++) { > struct resource *res; > + > res = platform_get_resource(pdev, IORESOURCE_MEM, i); > if (!res) { > - dev_dbg(dev, "Unable to find IOMEM region\n"); > - ret = -ENOENT; > - goto err_res; > + dev_err(dev, "Unable to find IOMEM region\n"); > + return -ENOENT; > } > > - data->sfrbases[i] = ioremap(res->start, resource_size(res)); > + data->sfrbases[i] = devm_request_and_ioremap(dev, res); devm_request_and_ioremap() is deprecated. Please use devm_ioremap_resource(). > if (!data->sfrbases[i]) { In case of devm_ioremap_resource() remember to adjust this check to check for IS_ERR, not for NULL. > - dev_dbg(dev, "Unable to map IOMEM @ PA:%#x\n", > - res->start); > - ret = -ENOENT; > - goto err_res; > + dev_err(dev, "Unable to map IOMEM @ %#x\n", res- >start); This message will not be needed with devm_ioremap_resource() as it already prints a message if an error occurs. > + return -EBUSY; > } > } > > for (i = 0; i < data->nsfrs; i++) { > - ret = platform_get_irq(pdev, i); > - if (ret <= 0) { > - dev_dbg(dev, "Unable to find IRQ resource\n"); > - goto err_irq; > + int irq; > + > + irq = platform_get_irq(pdev, i); > + if (irq <= 0) { > + dev_err(dev, "Unable to find IRQ resource\n"); > + return -ENOENT; > } > > - ret = request_irq(ret, exynos_sysmmu_irq, 0, > - dev_name(dev), data); > + ret = devm_request_irq(dev, irq, exynos_sysmmu_irq, > + 0, dev_name(dev), data); > if (ret) { > - dev_dbg(dev, "Unabled to register interrupt handler\n"); > - goto err_irq; > + dev_err(dev, "Unable to register handler to irq %d\n", > + irq); > + return ret; > } > } > > - if (dev_get_platdata(dev)) { > - char *deli, *beg; > - struct sysmmu_platform_data *platdata = dev_get_platdata(dev); > - > - beg = platdata->clockname; > - > - for (deli = beg; (*deli != '\0') && (*deli != ','); deli++) > - /* NOTHING */; > + pm_runtime_enable(dev); > > - if (*deli == '\0') > - deli = NULL; > - else > - *deli = '\0'; > - > - data->clk[0] = clk_get(dev, beg); > - if (IS_ERR(data->clk[0])) { > - data->clk[0] = NULL; > - dev_dbg(dev, "No clock descriptor registered\n"); > - } > + __set_fault_handler(data, &default_fault_handler); > > - if (data->clk[0] && deli) { > - *deli = ','; > - data->clk[1] = clk_get(dev, deli + 1); > - if (IS_ERR(data->clk[1])) > - data->clk[1] = NULL; > - } > + data->sysmmu = dev; > + data->clk = devm_clk_get(dev, "sysmmu"); > + if (IS_ERR(data->clk)) { > + dev_info(dev, "No gate clock found!\n"); > + data->clk = NULL; Just a note: In common clock framework NULL is a valid value for a struct clk *, which should not be interpreted as a pointer, but as an opaque cookie. This is material for separate patch, but this should be fixed all around this driver so data->clk is for IS_ERR instead. Best regards, Tomasz > + } > > - data->dbgname = platdata->dbgname; > + ret = clk_prepare(data->clk); > + if (ret) { > + dev_err(dev, "Failed to prepare clk\n"); > + return ret; > } > > - data->sysmmu = dev; > rwlock_init(&data->lock); > INIT_LIST_HEAD(&data->node); > > - __set_fault_handler(data, &default_fault_handler); > - > - if (dev->parent) > - pm_runtime_enable(dev); > + platform_set_drvdata(pdev, data); > + dev_dbg(dev, "Probed and initialized\n"); > > - dev_dbg(dev, "(%s) Initialized\n", data->dbgname); > - return 0; > -err_irq: > - while (i-- > 0) { > - int irq; > - > - irq = platform_get_irq(pdev, i); > - free_irq(irq, data); > - } > -err_res: > - while (data->nsfrs-- > 0) > - iounmap(data->sfrbases[data->nsfrs]); > - kfree(data->sfrbases); > -err_init: > - kfree(data); > -err_alloc: > - dev_err(dev, "Failed to initialize\n"); > return ret; > } > > -static struct platform_driver exynos_sysmmu_driver = { > - .probe = exynos_sysmmu_probe, > - .driver = { > +#ifdef CONFIG_OF > +static struct of_device_id sysmmu_of_match[] __initconst = { > + { .compatible = "samsung,exynos4210-sysmmu", }, > + { }, > +}; > +#endif > + > +static struct platform_driver exynos_sysmmu_driver __refdata = { > + .probe = exynos_sysmmu_probe, > + .driver = { > .owner = THIS_MODULE, > .name = "exynos-sysmmu", > + .of_match_table = of_match_ptr(sysmmu_of_match), > } > }; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/