Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752487AbaGNI3B (ORCPT ); Mon, 14 Jul 2014 04:29:01 -0400 Received: from mailout3.w1.samsung.com ([210.118.77.13]:32351 "EHLO mailout3.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752549AbaGNI2U (ORCPT ); Mon, 14 Jul 2014 04:28:20 -0400 X-AuditID: cbfec7f5-b7f626d000004b39-4e-53c394a164c2 From: Marek Szyprowski To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Marek Szyprowski , linaro-mm-sig@lists.linaro.org, devicetree@vger.kernel.org, Arnd Bergmann , Michal Nazarewicz , Grant Likely , Tomasz Figa , Sascha Hauer , Laura Abbott , Nishanth Peethambaran , Marc , Josh Cartwright , Catalin Marinas , Will Deacon , Paul Mackerras , Jon Medhurst , Joonsoo Kim , "Aneesh Kumar K.V." , Andrew Morton Subject: [PATCH v2 RESEND 3/4] drivers: dma-coherent: add initialization from device tree Date: Mon, 14 Jul 2014 10:28:06 +0200 Message-id: <1405326487-15346-4-git-send-email-m.szyprowski@samsung.com> X-Mailer: git-send-email 1.9.2 In-reply-to: <1405326487-15346-1-git-send-email-m.szyprowski@samsung.com> References: <1405326487-15346-1-git-send-email-m.szyprowski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrPLMWRmVeSWpSXmKPExsVy+t/xq7oLpxwONnjZxmUxZ/0aNovHr+ex WPyddIzd4v2yHkaL+UfOsVoc+LOD0WJldzObxc517xgtzja9YbfY3jmD3eLLlYdMFpseX2O1 uLxrDpvF2iN32S02vDzIZLHgeAurxZ/pchZrjixmt/i7fROLxfoZr1ksFs6/z27x8uMJFgcx jzXz1jB6/P41idHjcl8vk8fOWXfZPbreXmHyuHNtD5vHiRm/WTweHNrM4rF5Sb3H7X+PmT3W /XnF5NH/18Bj7q4+Ro++LasYPT5vkgvgj+KySUnNySxLLdK3S+DKeDNrNmPBJtuKvnXL2BsY Fxh1MXJySAiYSKxYNpcNwhaTuHBvPZDNxSEksJRR4vPj7+wgCSGBPiaJd3/8QGw2AUOJrrdd YA0iAm4S/9YdAmtgFnjNKrHi0WcWkISwQLTEt1PrgWwODhYBVYnF6+JAwrwCHhIvu6+wQyyT k/j/cgUTiM0p4Ckx4/N7qF0eEu8v97JOYORdwMiwilE0tTS5oDgpPddIrzgxt7g0L10vOT93 EyMkkr7uYFx6zOoQowAHoxIPbwH/4WAh1sSy4srcQ4wSHMxKIrzhbkAh3pTEyqrUovz4otKc 1OJDjEwcnFINjId3Os1Orb96r4ZhxzOtHcV1u+YJv/7gp8YwJW09p5cDt4TwXtE3T6Orliu9 /yFY1PhU3zhGWUhlqlYTa9et2i9fqy3Wsl3yiI6YP/2JQY3zq/U7nx9LyC65xv0he4mOqcGq qnqWJdcl5K4fFd4vb9T/0eLwv6qZr4Kdbqbs5D+yueIGxy2BICWW4oxEQy3mouJEAK0To2SC AgAA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Initialization procedure of dma coherent pool has been split into two parts, so memory pool can now be initialized without assigning to particular struct device. Then initialized region can be assigned to more than one struct device. To protect from concurent allocations from different devices, a spinlock has been added to dma_coherent_mem structure. The last part of this patch adds support for handling 'shared-dma-pool' reserved-memory device tree nodes. Signed-off-by: Marek Szyprowski --- drivers/base/dma-coherent.c | 137 ++++++++++++++++++++++++++++++++++++++------ 1 file changed, 118 insertions(+), 19 deletions(-) diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c index 7d6e84a51424..7185a4f247e1 100644 --- a/drivers/base/dma-coherent.c +++ b/drivers/base/dma-coherent.c @@ -14,11 +14,14 @@ struct dma_coherent_mem { int size; int flags; unsigned long *bitmap; + spinlock_t spinlock; }; -int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, - dma_addr_t device_addr, size_t size, int flags) +static int dma_init_coherent_memory(phys_addr_t phys_addr, dma_addr_t device_addr, + size_t size, int flags, + struct dma_coherent_mem **mem) { + struct dma_coherent_mem *dma_mem = NULL; void __iomem *mem_base = NULL; int pages = size >> PAGE_SHIFT; int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); @@ -27,27 +30,26 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, goto out; if (!size) goto out; - if (dev->dma_mem) - goto out; - - /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */ mem_base = ioremap(phys_addr, size); if (!mem_base) goto out; - dev->dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL); - if (!dev->dma_mem) + dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL); + if (!dma_mem) goto out; - dev->dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL); - if (!dev->dma_mem->bitmap) + dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL); + if (!dma_mem->bitmap) goto free1_out; - dev->dma_mem->virt_base = mem_base; - dev->dma_mem->device_base = device_addr; - dev->dma_mem->pfn_base = PFN_DOWN(phys_addr); - dev->dma_mem->size = pages; - dev->dma_mem->flags = flags; + dma_mem->virt_base = mem_base; + dma_mem->device_base = device_addr; + dma_mem->pfn_base = PFN_DOWN(phys_addr); + dma_mem->size = pages; + dma_mem->flags = flags; + spin_lock_init(&dma_mem->spinlock); + + *mem = dma_mem; if (flags & DMA_MEMORY_MAP) return DMA_MEMORY_MAP; @@ -55,12 +57,51 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, return DMA_MEMORY_IO; free1_out: - kfree(dev->dma_mem); + kfree(dma_mem); out: if (mem_base) iounmap(mem_base); return 0; } + +static void dma_release_coherent_memory(struct dma_coherent_mem *mem) +{ + if (!mem) + return; + iounmap(mem->virt_base); + kfree(mem->bitmap); + kfree(mem); +} + +static int dma_assign_coherent_memory(struct device *dev, + struct dma_coherent_mem *mem) +{ + if (dev->dma_mem) + return -EBUSY; + + dev->dma_mem = mem; + /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */ + + return 0; +} + +int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, + dma_addr_t device_addr, size_t size, int flags) +{ + struct dma_coherent_mem *mem; + int ret; + + ret = dma_init_coherent_memory(phys_addr, device_addr, size, flags, + &mem); + if (ret == 0) + return 0; + + if (dma_assign_coherent_memory(dev, mem) == 0) + return ret; + + dma_release_coherent_memory(mem); + return 0; +} EXPORT_SYMBOL(dma_declare_coherent_memory); void dma_release_declared_memory(struct device *dev) @@ -69,10 +110,8 @@ void dma_release_declared_memory(struct device *dev) if (!mem) return; + dma_release_coherent_memory(mem); dev->dma_mem = NULL; - iounmap(mem->virt_base); - kfree(mem->bitmap); - kfree(mem); } EXPORT_SYMBOL(dma_release_declared_memory); @@ -80,6 +119,7 @@ void *dma_mark_declared_memory_occupied(struct device *dev, dma_addr_t device_addr, size_t size) { struct dma_coherent_mem *mem = dev->dma_mem; + unsigned long flags; int pos, err; size += device_addr & ~PAGE_MASK; @@ -87,8 +127,11 @@ void *dma_mark_declared_memory_occupied(struct device *dev, if (!mem) return ERR_PTR(-EINVAL); + spin_lock_irqsave(&mem->spinlock, flags); pos = (device_addr - mem->device_base) >> PAGE_SHIFT; err = bitmap_allocate_region(mem->bitmap, pos, get_order(size)); + spin_unlock_irqrestore(&mem->spinlock, flags); + if (err != 0) return ERR_PTR(err); return mem->virt_base + (pos << PAGE_SHIFT); @@ -115,6 +158,7 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size, { struct dma_coherent_mem *mem; int order = get_order(size); + unsigned long flags; int pageno; if (!dev) @@ -124,6 +168,7 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size, return 0; *ret = NULL; + spin_lock_irqsave(&mem->spinlock, flags); if (unlikely(size > (mem->size << PAGE_SHIFT))) goto err; @@ -138,10 +183,12 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size, *dma_handle = mem->device_base + (pageno << PAGE_SHIFT); *ret = mem->virt_base + (pageno << PAGE_SHIFT); memset(*ret, 0, size); + spin_unlock_irqrestore(&mem->spinlock, flags); return 1; err: + spin_unlock_irqrestore(&mem->spinlock, flags); /* * In the case where the allocation can not be satisfied from the * per-device area, try to fall back to generic memory if the @@ -171,8 +218,11 @@ int dma_release_from_coherent(struct device *dev, int order, void *vaddr) if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) { int page = (vaddr - mem->virt_base) >> PAGE_SHIFT; + unsigned long flags; + spin_lock_irqsave(&mem->spinlock, flags); bitmap_release_region(mem->bitmap, page, order); + spin_unlock_irqrestore(&mem->spinlock, flags); return 1; } return 0; @@ -218,3 +268,52 @@ int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma, return 0; } EXPORT_SYMBOL(dma_mmap_from_coherent); + +/* + * Support for reserved memory regions defined in device tree + */ +#ifdef CONFIG_OF_RESERVED_MEM +#include +#include +#include + +static void rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev) +{ + struct dma_coherent_mem *mem = rmem->priv; + if (!mem && + dma_init_coherent_memory(rmem->base, rmem->base, rmem->size, + DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE, + &mem) != DMA_MEMORY_MAP) { + pr_info("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n", + &rmem->base, (unsigned long)rmem->size / SZ_1M); + return; + } + rmem->priv = mem; + dma_assign_coherent_memory(dev, mem); +} + +static void rmem_dma_device_release(struct reserved_mem *rmem, + struct device *dev) +{ + dev->dma_mem = NULL; +} + +static const struct reserved_mem_ops rmem_dma_ops = { + .device_init = rmem_dma_device_init, + .device_release = rmem_dma_device_release, +}; + +static int __init rmem_dma_setup(struct reserved_mem *rmem) +{ + unsigned long node = rmem->fdt_node; + + if (of_get_flat_dt_prop(node, "reusable", NULL)) + return -EINVAL; + + rmem->ops = &rmem_dma_ops; + pr_info("Reserved memory: created DMA memory pool at %pa, size %ld MiB\n", + &rmem->base, (unsigned long)rmem->size / SZ_1M); + return 0; +} +RESERVEDMEM_OF_DECLARE(dma, "shared-dma-pool", rmem_dma_setup); +#endif -- 1.9.2 -- 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/