Re: [PATCH] powerpc-powernv: added tce_get callback for powernv platform

On 05/09/12 05:41, Benjamin Herrenschmidt wrote:

On Tue, 2012-09-04 at 17:35 +1000, Alexey Kardashevskiy wrote:

quoted

The upcoming VFIO support requires a way to know which
entry in the TCE map is not empty in order to do cleanup
at QEMU exit/crash. This patch adds such functionality
to POWERNV platform code.

Signed-off-by: Alexey Kardashevskiy <redacted>
---
  arch/powerpc/platforms/powernv/pci.c |    6 ++++++
  1 file changed, 6 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
index be3cfc5..61f8068 100644
--- a/arch/powerpc/platforms/powernv/pci.c
+++ b/arch/powerpc/platforms/powernv/pci.c

@@ -447,6 +447,11 @@ static void pnv_tce_free(struct iommu_table *tbl, long index, long npages)
  		pnv_tce_invalidate(tbl, tces, tcep - 1);
  }

+static unsigned long pnv_tce_get(struct iommu_table *tbl, long index)
+{
+	return ((u64 *)tbl->it_base)[index - tbl->it_offset] & IOMMU_PAGE_MASK;
+}

Why the masking here ?

Oops. No reason. Will remove.

Cheers,
Ben.

quoted

  void pnv_pci_setup_iommu_table(struct iommu_table *tbl,
  			       void *tce_mem, u64 tce_size,
  			       u64 dma_offset)

@@ -597,6 +602,7 @@ void __init pnv_pci_init(void)
  	ppc_md.pci_dma_dev_setup = pnv_pci_dma_dev_setup;
  	ppc_md.tce_build = pnv_tce_build;
  	ppc_md.tce_free = pnv_tce_free;
+	ppc_md.tce_get = pnv_tce_get;
  	ppc_md.pci_probe_mode = pnv_pci_probe_mode;
  	set_pci_dma_ops(&dma_iommu_ops);

-- 
Alexey