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powerpc/powernv: Remove unused pnv_npu_try_dma_set_bypass() function
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Neither pnv_npu_try_dma_set_bypass() nor the pnv_npu_dma_set_32() and
pnv_npu_dma_set_bypass() helpers called by it are used anywhere in the
kernel tree, so remove them.

mpe: They're unused since 2d6ad41 ("powerpc/powernv: use the
generic iommu bypass code") removed the last usage.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190903165147.11099-1-hch@lst.de
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Christoph Hellwig authored and Michael Ellerman committed Sep 11, 2019
1 parent 6f62a82 commit b4d37a7
Showing 1 changed file with 0 additions and 99 deletions.
99 changes: 0 additions & 99 deletions arch/powerpc/platforms/powernv/npu-dma.c
Original file line number Diff line number Diff line change
Expand Up @@ -192,105 +192,6 @@ static long pnv_npu_unset_window(struct iommu_table_group *table_group, int num)
return 0;
}

/*
* Enables 32 bit DMA on NPU.
*/
static void pnv_npu_dma_set_32(struct pnv_ioda_pe *npe)
{
struct pci_dev *gpdev;
struct pnv_ioda_pe *gpe;
int64_t rc;

/*
* Find the assoicated PCI devices and get the dma window
* information from there.
*/
if (!npe->pdev || !(npe->flags & PNV_IODA_PE_DEV))
return;

gpe = get_gpu_pci_dev_and_pe(npe, &gpdev);
if (!gpe)
return;

rc = pnv_npu_set_window(&npe->table_group, 0,
gpe->table_group.tables[0]);

/*
* NVLink devices use the same TCE table configuration as
* their parent device so drivers shouldn't be doing DMA
* operations directly on these devices.
*/
set_dma_ops(&npe->pdev->dev, &dma_dummy_ops);
}

/*
* Enables bypass mode on the NPU. The NPU only supports one
* window per link, so bypass needs to be explicitly enabled or
* disabled. Unlike for a PHB3 bypass and non-bypass modes can't be
* active at the same time.
*/
static int pnv_npu_dma_set_bypass(struct pnv_ioda_pe *npe)
{
struct pnv_phb *phb = npe->phb;
int64_t rc = 0;
phys_addr_t top = memblock_end_of_DRAM();

if (phb->type != PNV_PHB_NPU_NVLINK || !npe->pdev)
return -EINVAL;

rc = pnv_npu_unset_window(&npe->table_group, 0);
if (rc != OPAL_SUCCESS)
return rc;

/* Enable the bypass window */

top = roundup_pow_of_two(top);
dev_info(&npe->pdev->dev, "Enabling bypass for PE %x\n",
npe->pe_number);
rc = opal_pci_map_pe_dma_window_real(phb->opal_id,
npe->pe_number, npe->pe_number,
0 /* bypass base */, top);

if (rc == OPAL_SUCCESS)
pnv_pci_ioda2_tce_invalidate_entire(phb, false);

return rc;
}

void pnv_npu_try_dma_set_bypass(struct pci_dev *gpdev, bool bypass)
{
int i;
struct pnv_phb *phb;
struct pci_dn *pdn;
struct pnv_ioda_pe *npe;
struct pci_dev *npdev;

for (i = 0; ; ++i) {
npdev = pnv_pci_get_npu_dev(gpdev, i);

if (!npdev)
break;

pdn = pci_get_pdn(npdev);
if (WARN_ON(!pdn || pdn->pe_number == IODA_INVALID_PE))
return;

phb = pci_bus_to_host(npdev->bus)->private_data;

/* We only do bypass if it's enabled on the linked device */
npe = &phb->ioda.pe_array[pdn->pe_number];

if (bypass) {
dev_info(&npdev->dev,
"Using 64-bit DMA iommu bypass\n");
pnv_npu_dma_set_bypass(npe);
} else {
dev_info(&npdev->dev, "Using 32-bit DMA via iommu\n");
pnv_npu_dma_set_32(npe);
}
}
}

#ifdef CONFIG_IOMMU_API
/* Switch ownership from platform code to external user (e.g. VFIO) */
static void pnv_npu_take_ownership(struct iommu_table_group *table_group)
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