Re: [PATCH v8 22/45] powerpc/powernv/ioda1: Support releasing IODA1 TCE table

[Alexey Kardashevskiy <aik@xxxxxxxxx>]

On 04/20/2016 11:15 AM, Gavin Shan wrote:
> On Tue, Apr 19, 2016 at 02:28:51PM +1000, Alexey Kardashevskiy wrote:
> > On 02/17/2016 02:44 PM, Gavin Shan wrote:
> > > pnv_pci_ioda_table_free_pages() can be reused to release the IODA1
> > > TCE table when releasing IODA1 PE in subsequent patches.
> > >
> > > This renames the following functions to support releasing IODA1 TCE
> > > table: pnv_pci_ioda2_table_free_pages() to pnv_pci_ioda_table_free_pages(),
> > > pnv_pci_ioda2_table_do_free_pages() to pnv_pci_ioda_table_do_free_pages().
> > > No logical changes introduced.
> >
> > I can only see renaming here but it seems (from
> > IODA_architecture_04-14-2008.pdf) that IODA1 does not support multi-level TCE
> > tables in the way IODA2 does.
>
> Note that the change was proposed by you in last round.

Hm. I do not recall proposing exactly that :-/

> Yes, TVE on P7IOC
> doesn't support multiple levels of TCE tables.

I thought it supports 2 levels.

> In this case, we will always
> have "tbl->it_indirect_levels" to 1, right?

Nope, it will be 0. But it is still ugly to use release function but not to 
use its allocating counterpart which is pnv_pci_ioda2_table_alloc_pages().

I suggest having pnv_pci_ioda1_table_free_pages() which will be just a 
single free_pages() call. If you need some ioda*-common code to free a 
table, then define pnv_ioda1_iommu_ops::free().

> > > Signed-off-by: Gavin Shan <gwshan@xxxxxxxxxxxxxxxxxx>
> > > ---
> > >   arch/powerpc/platforms/powernv/pci-ioda.c | 18 +++++++++---------
> > >   1 file changed, 9 insertions(+), 9 deletions(-)
> > >
> > > diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
> > > index d360607..077f9db 100644
> > > --- a/arch/powerpc/platforms/powernv/pci-ioda.c
> > > +++ b/arch/powerpc/platforms/powernv/pci-ioda.c
> > > @@ -51,7 +51,7 @@
> > >   #define POWERNV_IOMMU_DEFAULT_LEVELS	1
> > >   #define POWERNV_IOMMU_MAX_LEVELS	5
> > >
> > > -static void pnv_pci_ioda2_table_free_pages(struct iommu_table *tbl);
> > > +static void pnv_pci_ioda_table_free_pages(struct iommu_table *tbl);
> > >
> > >   static void pe_level_printk(const struct pnv_ioda_pe *pe, const char *level,
> > >   			    const char *fmt, ...)
> > > @@ -1352,7 +1352,7 @@ static void pnv_pci_ioda2_release_dma_pe(struct pci_dev *dev, struct pnv_ioda_pe
> > >   		iommu_group_put(pe->table_group.group);
> > >   		BUG_ON(pe->table_group.group);
> > >   	}
> > > -	pnv_pci_ioda2_table_free_pages(tbl);
> > > +	pnv_pci_ioda_table_free_pages(tbl);
> > >   	iommu_free_table(tbl, of_node_full_name(dev->dev.of_node));
> > >   }
> > >
> > > @@ -1946,7 +1946,7 @@ static void pnv_ioda2_tce_free(struct iommu_table *tbl, long index,
> > >
> > >   static void pnv_ioda2_table_free(struct iommu_table *tbl)
> > >   {
> > > -	pnv_pci_ioda2_table_free_pages(tbl);
> > > +	pnv_pci_ioda_table_free_pages(tbl);
> > >   	iommu_free_table(tbl, "pnv");
> > >   }
> > >
> > > @@ -2448,7 +2448,7 @@ static __be64 *pnv_pci_ioda2_table_do_alloc_pages(int nid, unsigned shift,
> > >   	return addr;
> > >   }
> > >
> > > -static void pnv_pci_ioda2_table_do_free_pages(__be64 *addr,
> > > +static void pnv_pci_ioda_table_do_free_pages(__be64 *addr,
> > >   		unsigned long size, unsigned level);
> > >
> > >   static long pnv_pci_ioda2_table_alloc_pages(int nid, __u64 bus_offset,
> > > @@ -2487,7 +2487,7 @@ static long pnv_pci_ioda2_table_alloc_pages(int nid, __u64 bus_offset,
> > >   	 * release partially allocated table.
> > >   	 */
> > >   	if (offset < tce_table_size) {
> > > -		pnv_pci_ioda2_table_do_free_pages(addr,
> > > +		pnv_pci_ioda_table_do_free_pages(addr,
> > >   				1ULL << (level_shift - 3), levels - 1);
> > >   		return -ENOMEM;
> > >   	}
> > > @@ -2505,7 +2505,7 @@ static long pnv_pci_ioda2_table_alloc_pages(int nid, __u64 bus_offset,
> > >   	return 0;
> > >   }
> > >
> > > -static void pnv_pci_ioda2_table_do_free_pages(__be64 *addr,
> > > +static void pnv_pci_ioda_table_do_free_pages(__be64 *addr,
> > >   		unsigned long size, unsigned level)
> > >   {
> > >   	const unsigned long addr_ul = (unsigned long) addr &
> > > @@ -2521,7 +2521,7 @@ static void pnv_pci_ioda2_table_do_free_pages(__be64 *addr,
> > >   			if (!(hpa & (TCE_PCI_READ | TCE_PCI_WRITE)))
> > >   				continue;
> > >
> > > -			pnv_pci_ioda2_table_do_free_pages(__va(hpa), size,
> > > +			pnv_pci_ioda_table_do_free_pages(__va(hpa), size,
> > >   					level - 1);
> > >   		}
> > >   	}
> > > @@ -2529,7 +2529,7 @@ static void pnv_pci_ioda2_table_do_free_pages(__be64 *addr,
> > >   	free_pages(addr_ul, get_order(size << 3));
> > >   }
> > >
> > > -static void pnv_pci_ioda2_table_free_pages(struct iommu_table *tbl)
> > > +static void pnv_pci_ioda_table_free_pages(struct iommu_table *tbl)
> > >   {
> > >   	const unsigned long size = tbl->it_indirect_levels ?
> > >   			tbl->it_level_size : tbl->it_size;
> > > @@ -2537,7 +2537,7 @@ static void pnv_pci_ioda2_table_free_pages(struct iommu_table *tbl)
> > >   	if (!tbl->it_size)
> > >   		return;
> > >
> > > -	pnv_pci_ioda2_table_do_free_pages((__be64 *)tbl->it_base, size,
> > > +	pnv_pci_ioda_table_do_free_pages((__be64 *)tbl->it_base, size,
> > >   			tbl->it_indirect_levels);
> > >   }
> >
> >
> > --
> > Alexey


--
Alexey
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