Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933856AbdDFKDU (ORCPT ); Thu, 6 Apr 2017 06:03:20 -0400 Received: from foss.arm.com ([217.140.101.70]:40452 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753742AbdDFKDL (ORCPT ); Thu, 6 Apr 2017 06:03:11 -0400 Subject: Re: [PATCH V10 03/12] of: dma: Move range size workaround to of_dma_get_range() To: Frank Rowand , Sricharan R , will.deacon@arm.com, joro@8bytes.org, lorenzo.pieralisi@arm.com, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, m.szyprowski@samsung.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, tn@semihalf.com, hanjun.guo@linaro.org, okaya@codeaurora.org, robh+dt@kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, sudeep.holla@arm.com, rjw@rjwysocki.net, lenb@kernel.org, catalin.marinas@arm.com, arnd@arndb.de, linux-arch@vger.kernel.org, gregkh@linuxfoundation.org References: <1489086061-9356-1-git-send-email-sricharan@codeaurora.org> <1491301105-5274-1-git-send-email-sricharan@codeaurora.org> <1491301105-5274-4-git-send-email-sricharan@codeaurora.org> <58E5DF13.2020700@gmail.com> From: Robin Murphy Message-ID: <4d6206a4-fa5d-00b8-b536-fd9fe68fb168@arm.com> Date: Thu, 6 Apr 2017 11:03:02 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <58E5DF13.2020700@gmail.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3431 Lines: 100 Hi Frank, On 06/04/17 07:24, Frank Rowand wrote: > On 04/04/17 03:18, Sricharan R wrote: >> From: Laurent Pinchart >> >> Invalid dma-ranges values should be worked around when retrieving the >> DMA range in of_dma_get_range(), not by all callers of the function. >> This isn't much of a problem now that we have a single caller, but that >> situation will change when moving DMA configuration to device probe >> time. > > Please drop this patch from the series. I just now sent Rob an > alternative that reflects other changes that have occurred since > this patch series was first created many, many moons ago > (https://lkml.org/lkml/2017/4/6/53). Fine by me too - if we can get rid of that dubious fixup altogether, all the better. Feel free to transfer my Reviewed-by to your patch if you like. Thanks, Robin. > Thanks, > > Frank > >> >> Tested-by: Marek Szyprowski >> Signed-off-by: Laurent Pinchart >> --- >> drivers/of/address.c | 20 ++++++++++++++++++-- >> drivers/of/device.c | 15 --------------- >> 2 files changed, 18 insertions(+), 17 deletions(-) >> >> diff --git a/drivers/of/address.c b/drivers/of/address.c >> index 02b2903..6aeb816 100644 >> --- a/drivers/of/address.c >> +++ b/drivers/of/address.c >> @@ -819,8 +819,8 @@ void __iomem *of_io_request_and_map(struct device_node *np, int index, >> * CPU addr (phys_addr_t) : pna cells >> * size : nsize cells >> * >> - * It returns -ENODEV if "dma-ranges" property was not found >> - * for this device in DT. >> + * Return 0 on success, -ENODEV if the "dma-ranges" property was not found for >> + * this device in DT, or -EINVAL if the CPU address or size is invalid. >> */ >> int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size) >> { >> @@ -880,6 +880,22 @@ int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *siz >> *dma_addr = dmaaddr; >> >> *size = of_read_number(ranges + naddr + pna, nsize); >> + /* >> + * DT nodes sometimes incorrectly set the size as a mask. Work around >> + * those incorrect DT by computing the size as mask + 1. >> + */ >> + if (*size & 1) { >> + pr_warn("%s: size 0x%llx for dma-range in node(%s) set as mask\n", >> + __func__, *size, np->full_name); >> + *size = *size + 1; >> + } >> + >> + if (!*size) { >> + pr_err("%s: invalid size zero for dma-range in node(%s)\n", >> + __func__, np->full_name); >> + ret = -EINVAL; >> + goto out; >> + } >> >> pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n", >> *dma_addr, *paddr, *size); >> diff --git a/drivers/of/device.c b/drivers/of/device.c >> index b1e6beb..09dedd0 100644 >> --- a/drivers/of/device.c >> +++ b/drivers/of/device.c >> @@ -110,21 +110,6 @@ void of_dma_configure(struct device *dev, struct device_node *np) >> size = dev->coherent_dma_mask + 1; >> } else { >> offset = PFN_DOWN(paddr - dma_addr); >> - >> - /* >> - * Add a work around to treat the size as mask + 1 in case >> - * it is defined in DT as a mask. >> - */ >> - if (size & 1) { >> - dev_warn(dev, "Invalid size 0x%llx for dma-range\n", >> - size); >> - size = size + 1; >> - } >> - >> - if (!size) { >> - dev_err(dev, "Adjusted size 0x%llx invalid\n", size); >> - return; >> - } >> dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset); >> } >> >>