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PPC: POWERNV: move iommu_add_device earlier

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The current implementation of IOMMU on sPAPR does not use iommu_ops
and therefore does not call IOMMU API's bus_set_iommu() which
1) sets iommu_ops for a bus
2) registers a bus notifier
Instead, PCI devices are added to IOMMU groups from
subsys_initcall_sync(tce_iommu_init) which does basically the same
thing without using iommu_ops callbacks.

However Freescale PAMU driver (https://lkml.org/lkml/2013/7/1/158)
implements iommu_ops and when tce_iommu_init is called, every PCI device
is already added to some group so there is a conflict.

This patch does 2 things:
1. removes the loop in which PCI devices were added to groups and
adds explicit iommu_add_device() calls to add devices as soon as they get
the iommu_table pointer assigned to them.
2. moves a bus notifier to powernv code in order to avoid conflict with
the notifier from Freescale driver.

iommu_add_device() and iommu_del_device() are public now.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Alexey Kardashevskiy
2013-11-21 17:43:14 +11:00
committed by Benjamin Herrenschmidt
parent 7e1ce5a492
commit d905c5df9a
6 changed files with 72 additions and 53 deletions
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33
arch/powerpc/platforms/powernv/pci.c
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@@ -536,7 +536,7 @@ static void pnv_pci_dma_fallback_setup(struct pci_controller *hose,
pdn->iommu_table = pnv_pci_setup_bml_iommu(hose);
if (!pdn->iommu_table)
return;
set_iommu_table_base(&pdev->dev, pdn->iommu_table);
set_iommu_table_base_and_group(&pdev->dev, pdn->iommu_table);
}
static void pnv_pci_dma_dev_setup(struct pci_dev *pdev)
@@ -657,3 +657,34 @@ void __init pnv_pci_init(void)
ppc_md.teardown_msi_irqs = pnv_teardown_msi_irqs;
#endif
}
static int tce_iommu_bus_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
switch (action) {
case BUS_NOTIFY_ADD_DEVICE:
return iommu_add_device(dev);
case BUS_NOTIFY_DEL_DEVICE:
if (dev->iommu_group)
iommu_del_device(dev);
return 0;
default:
return 0;
}
}
static struct notifier_block tce_iommu_bus_nb = {
.notifier_call = tce_iommu_bus_notifier,
};
static int __init tce_iommu_bus_notifier_init(void)
{
BUILD_BUG_ON(PAGE_SIZE < IOMMU_PAGE_SIZE);
bus_register_notifier(&pci_bus_type, &tce_iommu_bus_nb);
return 0;
}
subsys_initcall_sync(tce_iommu_bus_notifier_init);