From: Lorenzo Pieralisi <lorenzo.pieralisi-5wv7dgnIgG8@public.gmane.org> To: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org> Cc: gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-acpi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, sudeep.holla-5wv7dgnIgG8@public.gmane.org, frowand.list-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, hch-jcswGhMUV9g@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Subject: Re: [PATCH v2 6/7] ACPI/IORT: Don't set default coherent DMA mask Date: Wed, 25 Jul 2018 16:27:47 +0100 [thread overview] Message-ID: <20180725152747.GA5080@red-moon> (raw) In-Reply-To: <3525869e8e7530128bf9718ae8af7d7564b3c684.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> On Mon, Jul 23, 2018 at 11:16:11PM +0100, Robin Murphy wrote: > Now that we can track upstream DMA constraints properly with > bus_dma_mask instead of trying (and failing) to maintain it in > coherent_dma_mask, it doesn't make much sense for the firmware code to > be touching the latter at all. It's merely papering over bugs wherein a > driver has failed to call dma_set_coherent_mask() *and* the bus code has > not initialised any default value. Nit: I do not think the driver had a chance to probe and therefore call dma_set_coherent_mask() before iort_dma_setup() is executed, right ? Anyway, the patch makes perfect sense: Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi-5wv7dgnIgG8@public.gmane.org> > We don't really want to encourage more drivers coercing dma_mask so > we'll continue to fix that up if necessary, but add a warning to help > flush out any such buggy bus code that remains. > > CC: Lorenzo Pieralisi <lorenzo.pieralisi-5wv7dgnIgG8@public.gmane.org> > CC: Hanjun Guo <hanjun.guo-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> > CC: Sudeep Holla <sudeep.holla-5wv7dgnIgG8@public.gmane.org> > Signed-off-by: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org> > --- > drivers/acpi/arm64/iort.c | 22 +++++++++++----------- > 1 file changed, 11 insertions(+), 11 deletions(-) > > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > index bc51cff5505e..08f26db2da7e 100644 > --- a/drivers/acpi/arm64/iort.c > +++ b/drivers/acpi/arm64/iort.c > @@ -978,20 +978,20 @@ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) > int ret, msb; > > /* > - * Set default coherent_dma_mask to 32 bit. Drivers are expected to > - * setup the correct supported mask. > + * If @dev is expected to be DMA-capable then the bus code that created > + * it should have initialised its dma_mask pointer by this point. For > + * now, we'll continue the legacy behaviour of coercing it to the > + * coherent mask if not, but we'll no longer do so quietly. > */ > - if (!dev->coherent_dma_mask) > - dev->coherent_dma_mask = DMA_BIT_MASK(32); > - > - /* > - * Set it to coherent_dma_mask by default if the architecture > - * code has not set it. > - */ > - if (!dev->dma_mask) > + if (!dev->dma_mask) { > + dev_warn(dev, "DMA mask not set\n"); > dev->dma_mask = &dev->coherent_dma_mask; > + } > > - size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); > + if (dev->coherent_dma_mask) > + size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); > + else > + size = 1ULL << 32; > > if (dev_is_pci(dev)) { > ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size); > -- > 2.17.1.dirty >
WARNING: multiple messages have this Message-ID (diff)
From: lorenzo.pieralisi@arm.com (Lorenzo Pieralisi) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 6/7] ACPI/IORT: Don't set default coherent DMA mask Date: Wed, 25 Jul 2018 16:27:47 +0100 [thread overview] Message-ID: <20180725152747.GA5080@red-moon> (raw) In-Reply-To: <3525869e8e7530128bf9718ae8af7d7564b3c684.1532382222.git.robin.murphy@arm.com> On Mon, Jul 23, 2018 at 11:16:11PM +0100, Robin Murphy wrote: > Now that we can track upstream DMA constraints properly with > bus_dma_mask instead of trying (and failing) to maintain it in > coherent_dma_mask, it doesn't make much sense for the firmware code to > be touching the latter at all. It's merely papering over bugs wherein a > driver has failed to call dma_set_coherent_mask() *and* the bus code has > not initialised any default value. Nit: I do not think the driver had a chance to probe and therefore call dma_set_coherent_mask() before iort_dma_setup() is executed, right ? Anyway, the patch makes perfect sense: Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > We don't really want to encourage more drivers coercing dma_mask so > we'll continue to fix that up if necessary, but add a warning to help > flush out any such buggy bus code that remains. > > CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > CC: Hanjun Guo <hanjun.guo@linaro.org> > CC: Sudeep Holla <sudeep.holla@arm.com> > Signed-off-by: Robin Murphy <robin.murphy@arm.com> > --- > drivers/acpi/arm64/iort.c | 22 +++++++++++----------- > 1 file changed, 11 insertions(+), 11 deletions(-) > > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > index bc51cff5505e..08f26db2da7e 100644 > --- a/drivers/acpi/arm64/iort.c > +++ b/drivers/acpi/arm64/iort.c > @@ -978,20 +978,20 @@ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) > int ret, msb; > > /* > - * Set default coherent_dma_mask to 32 bit. Drivers are expected to > - * setup the correct supported mask. > + * If @dev is expected to be DMA-capable then the bus code that created > + * it should have initialised its dma_mask pointer by this point. For > + * now, we'll continue the legacy behaviour of coercing it to the > + * coherent mask if not, but we'll no longer do so quietly. > */ > - if (!dev->coherent_dma_mask) > - dev->coherent_dma_mask = DMA_BIT_MASK(32); > - > - /* > - * Set it to coherent_dma_mask by default if the architecture > - * code has not set it. > - */ > - if (!dev->dma_mask) > + if (!dev->dma_mask) { > + dev_warn(dev, "DMA mask not set\n"); > dev->dma_mask = &dev->coherent_dma_mask; > + } > > - size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); > + if (dev->coherent_dma_mask) > + size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); > + else > + size = 1ULL << 32; > > if (dev_is_pci(dev)) { > ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size); > -- > 2.17.1.dirty >
next prev parent reply other threads:[~2018-07-25 15:27 UTC|newest] Thread overview: 82+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-07-23 22:16 [PATCH v2 0/7] Stop losing firmware-set DMA masks Robin Murphy 2018-07-23 22:16 ` Robin Murphy 2018-07-23 22:16 ` [PATCH v2 1/7] ACPI/IORT: Support address size limit for root complexes Robin Murphy 2018-07-23 22:16 ` Robin Murphy 2018-07-23 22:16 ` [PATCH v2 2/7] dma-mapping: Generalise dma_32bit_limit flag Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <c1720f0181b66f711e4097d85149757b16a7b0a7.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 11:29 ` Christoph Hellwig 2018-07-25 11:29 ` Christoph Hellwig 2018-07-27 17:45 ` Grygorii Strashko via iommu 2018-07-27 17:45 ` Grygorii Strashko [not found] ` <7872d914-8ea7-06e4-4a0c-489023e098d6-l0cyMroinI0@public.gmane.org> 2018-07-27 20:11 ` Robin Murphy 2018-07-27 20:11 ` Robin Murphy [not found] ` <5354ef69-c54e-170b-62d4-5110dc60aa8f-5wv7dgnIgG8@public.gmane.org> 2018-07-27 20:41 ` Grygorii Strashko via iommu 2018-07-27 20:41 ` Grygorii Strashko 2018-07-23 22:16 ` [PATCH v2 3/7] ACPI/IORT: Set bus DMA mask as appropriate Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <07cbf8f77fac552dca9b4c85a9d3bd8ed5a4cd29.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 11:29 ` Christoph Hellwig 2018-07-25 11:29 ` Christoph Hellwig 2018-07-25 13:16 ` Lorenzo Pieralisi 2018-07-25 13:16 ` Lorenzo Pieralisi 2018-07-23 22:16 ` [PATCH v2 4/7] of/device: " Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <cc56f074b8da7e03a187b2363b1f2c2955d62c1c.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 11:30 ` Christoph Hellwig 2018-07-25 11:30 ` Christoph Hellwig 2018-07-23 22:16 ` [PATCH v2 5/7] iommu/dma: Respect bus DMA limit for IOVAs Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <d370670edae9c9c537a5280c5e7c96bf3ec7ed8f.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-26 8:58 ` Christoph Hellwig 2018-07-26 8:58 ` Christoph Hellwig 2018-07-23 22:16 ` [PATCH v2 6/7] ACPI/IORT: Don't set default coherent DMA mask Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <3525869e8e7530128bf9718ae8af7d7564b3c684.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 15:27 ` Lorenzo Pieralisi [this message] 2018-07-25 15:27 ` Lorenzo Pieralisi 2018-07-25 15:43 ` Robin Murphy 2018-07-25 15:43 ` Robin Murphy 2018-07-23 22:16 ` [PATCH v2 7/7] OF: " Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <66c08e4df2032fde82a2f97544f41fd3a2f24a94.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-26 23:52 ` Grygorii Strashko via iommu 2018-07-26 23:52 ` Grygorii Strashko 2018-07-27 0:22 ` Grygorii Strashko 2018-07-27 0:22 ` Grygorii Strashko [not found] ` <92d6b010-b5c0-fc59-0668-5b455e26c912-l0cyMroinI0@public.gmane.org> 2018-07-27 11:36 ` Robin Murphy 2018-07-27 11:36 ` Robin Murphy 2018-07-27 17:34 ` Grygorii Strashko 2018-07-27 17:34 ` Grygorii Strashko [not found] ` <108a6254-1257-5daf-deaa-69bc4db2ec77-l0cyMroinI0@public.gmane.org> 2018-07-27 19:46 ` Robin Murphy 2018-07-27 19:46 ` Robin Murphy [not found] ` <c7a9c7ae-1f4a-af9d-df78-1f48bb5c28a5-5wv7dgnIgG8@public.gmane.org> 2018-07-27 18:13 ` Russell King - ARM Linux 2018-07-27 18:13 ` Russell King - ARM Linux [not found] ` <20180727181302.GC17271-l+eeeJia6m9URfEZ8mYm6t73F7V6hmMc@public.gmane.org> 2018-07-27 18:45 ` Grygorii Strashko via iommu 2018-07-27 18:45 ` Grygorii Strashko [not found] ` <affa2718-5f3a-7439-db25-ce171a99414a-l0cyMroinI0@public.gmane.org> 2018-07-27 20:42 ` Robin Murphy 2018-07-27 20:42 ` Robin Murphy 2018-07-27 19:29 ` Robin Murphy 2018-07-27 19:29 ` Robin Murphy 2018-07-26 23:45 ` [PATCH v2 0/7] Stop losing firmware-set DMA masks Grygorii Strashko 2018-07-26 23:45 ` Grygorii Strashko [not found] ` <c73bc8d2-b745-ff31-1949-7a59ab04ede6-l0cyMroinI0@public.gmane.org> 2018-07-27 10:55 ` Robin Murphy 2018-07-27 10:55 ` Robin Murphy [not found] ` <8b8ac841-5c4c-ae27-21d5-d7aaaf4c277c-5wv7dgnIgG8@public.gmane.org> 2018-07-27 17:22 ` Grygorii Strashko via iommu 2018-07-27 17:22 ` Grygorii Strashko [not found] ` <cover.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 11:31 ` Christoph Hellwig 2018-07-25 11:31 ` Christoph Hellwig [not found] ` <20180725113122.GD24736-jcswGhMUV9g@public.gmane.org> 2018-07-25 12:11 ` Joerg Roedel 2018-07-25 12:11 ` Joerg Roedel 2018-07-25 12:12 ` Robin Murphy 2018-07-25 12:12 ` Robin Murphy [not found] ` <5e036ade-db0b-f628-a4a0-6d014d1d76c8-5wv7dgnIgG8@public.gmane.org> 2018-07-25 12:17 ` Will Deacon 2018-07-25 12:17 ` Will Deacon 2018-07-25 13:58 ` Ard Biesheuvel 2018-07-25 13:58 ` Ard Biesheuvel 2018-07-26 9:00 ` Christoph Hellwig 2018-07-26 9:00 ` Christoph Hellwig 2018-07-29 12:32 ` Arnd Bergmann 2018-07-29 12:32 ` Arnd Bergmann [not found] ` <CAK8P3a3HDJ6svNN_cwvegxu20yNv8+tvc0D1A6Ooeq8agawbFg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2018-07-31 11:24 ` Robin Murphy 2018-07-31 11:24 ` Robin Murphy [not found] ` <1ccccc4b-7d4c-a3ee-23a2-f108916705e9-5wv7dgnIgG8@public.gmane.org> 2018-08-06 10:01 ` Arnd Bergmann 2018-08-06 10:01 ` Arnd Bergmann [not found] ` <CAK8P3a3ZcOeHMR_qFnsBdXED+2X8_AEMKoS5MeAQhbapbGmm9w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2018-08-06 12:13 ` Christoph Hellwig 2018-08-06 12:13 ` Christoph Hellwig [not found] ` <20180806121334.GA5340-jcswGhMUV9g@public.gmane.org> 2018-08-06 12:13 ` Arnd Bergmann 2018-08-06 12:13 ` Arnd Bergmann
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