Message ID | 20210328074009.95932-1-sven@svenpeter.dev |
---|---|
Headers | show |
Series | Apple M1 DART IOMMU driver | expand |
On Sun, Mar 28, 2021 at 9:40 AM Sven Peter <sven@svenpeter.dev> wrote: I noticed only one detail here: > + - |+ > + dart2a: dart2a@82f00000 { > + compatible = "apple,t8103-dart"; > + reg = <0x82f00000 0x4000>; > + interrupts = <1 781 4>; > + #iommu-cells = <1>; > + }; The name of the iommu should be iommu@82f00000, not dart2a@82f00000. Arnd
On Sun, Mar 28, 2021 at 09:40:09AM +0200, Sven Peter wrote: > Apple's new SoCs use iommus for almost all peripherals. These Device > Address Resolution Tables must be setup before these peripherals can > act as DMA masters. > > Signed-off-by: Sven Peter <sven@svenpeter.dev> > --- > MAINTAINERS | 1 + > drivers/iommu/Kconfig | 14 + > drivers/iommu/Makefile | 1 + > drivers/iommu/apple-dart-iommu.c | 858 +++++++++++++++++++++++++++++++ > 4 files changed, 874 insertions(+) > create mode 100644 drivers/iommu/apple-dart-iommu.c [...] > +/* must be called with held domain->lock */ > +static int apple_dart_attach_stream(struct apple_dart_domain *domain, > + struct apple_dart *dart, u32 sid) > +{ > + unsigned long flags; > + struct apple_dart_stream *stream; > + struct io_pgtable_cfg *pgtbl_cfg; > + int ret; > + > + list_for_each_entry(stream, &domain->streams, stream_head) { > + if (stream->dart == dart && stream->sid == sid) { > + stream->num_devices++; > + return 0; > + } > + } > + > + spin_lock_irqsave(&dart->lock, flags); > + > + if (WARN_ON(dart->used_sids & BIT(sid))) { > + ret = -EINVAL; > + goto error; > + } > + > + stream = kzalloc(sizeof(*stream), GFP_KERNEL); > + if (!stream) { > + ret = -ENOMEM; > + goto error; > + } Just in case you missed it, a cocci bot noticed that you're using GFP_KERNEL to allocate while holding a spinlock here: https://lore.kernel.org/r/alpine.DEB.2.22.394.2104041724340.2958@hadrien Will
On Wed, Apr 7, 2021, at 12:42, Will Deacon wrote: > On Sun, Mar 28, 2021 at 09:40:09AM +0200, Sven Peter wrote: > > Apple's new SoCs use iommus for almost all peripherals. These Device > > Address Resolution Tables must be setup before these peripherals can > > act as DMA masters. > > > > Signed-off-by: Sven Peter <sven@svenpeter.dev> > > --- > > MAINTAINERS | 1 + > > drivers/iommu/Kconfig | 14 + > > drivers/iommu/Makefile | 1 + > > drivers/iommu/apple-dart-iommu.c | 858 +++++++++++++++++++++++++++++++ > > 4 files changed, 874 insertions(+) > > create mode 100644 drivers/iommu/apple-dart-iommu.c > > [...] > > > +/* must be called with held domain->lock */ > > +static int apple_dart_attach_stream(struct apple_dart_domain *domain, > > + struct apple_dart *dart, u32 sid) > > +{ > > + unsigned long flags; > > + struct apple_dart_stream *stream; > > + struct io_pgtable_cfg *pgtbl_cfg; > > + int ret; > > + > > + list_for_each_entry(stream, &domain->streams, stream_head) { > > + if (stream->dart == dart && stream->sid == sid) { > > + stream->num_devices++; > > + return 0; > > + } > > + } > > + > > + spin_lock_irqsave(&dart->lock, flags); > > + > > + if (WARN_ON(dart->used_sids & BIT(sid))) { > > + ret = -EINVAL; > > + goto error; > > + } > > + > > + stream = kzalloc(sizeof(*stream), GFP_KERNEL); > > + if (!stream) { > > + ret = -ENOMEM; > > + goto error; > > + } > > Just in case you missed it, a cocci bot noticed that you're using GFP_KERNEL > to allocate while holding a spinlock here: > > https://lore.kernel.org/r/alpine.DEB.2.22.394.2104041724340.2958@hadrien > Thanks for the reminder! I haven't replied yet because that one was found later when the bot picked up a (slightly earlier) version that Marc was using to bring up pcie I believe. I'll fix it for the next version. Sven