From: Will Deacon Date: Wed, 27 Aug 2014 13:40:58 +0000 (+0100) Subject: iommu: provide early initialisation hook for IOMMU drivers X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=452eb9f1aa8bb5d421a659c3393aa6a8cfd758fd;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git iommu: provide early initialisation hook for IOMMU drivers IOMMU drivers must be initialised before any of their upstream devices, otherwise the relevant iommu_ops won't be configured for the bus in question. To solve this, a number of IOMMU drivers use initcalls to initialise the driver before anything has a chance to be probed. Whilst this solves the immediate problem, it leaves the job of probing the IOMMU completely separate from the iommu_ops to configure the IOMMU, which are called on a per-bus basis and require the driver to figure out exactly which instance of the IOMMU is being requested. In particular, the add_device callback simply passes a struct device to the driver, which then has to parse firmware tables or probe buses to identify the relevant IOMMU instance. This patch takes the first step in addressing this problem by adding an early initialisation pass for IOMMU drivers, giving them the ability to store some per-instance data in their iommu_ops structure and store that in their of_node. This can later be used when parsing OF masters to identify the IOMMU instance in question. Change-Id: Ie7051c90c0f2e790d016eb465f10ddda48b99cd1 Acked-by: Arnd Bergmann Acked-by: Joerg Roedel Acked-by: Marek Szyprowski Tested-by: Robin Murphy Signed-off-by: Will Deacon [pdaly@codeaurora.org Resolve minor conflicts] --- diff --git a/include/linux/iommu.h b/include/linux/iommu.h index e57f0b9b5af5..a151cdec9cdd 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -128,6 +128,7 @@ extern struct dentry *iommu_debugfs_top; * @trigger_fault: trigger a fault on the device attached to an iommu domain * @reg_read: read an IOMMU register * @reg_write: write an IOMMU register + * @priv: per-instance data private to the iommu driver */ struct iommu_ops { bool (*capable)(enum iommu_cap); @@ -169,6 +170,7 @@ struct iommu_ops { unsigned long offset); unsigned long pgsize_bitmap; + void *priv; }; #define IOMMU_GROUP_NOTIFY_ADD_DEVICE 1 /* Device added */