On Wed, 2017-02-22 at 04:43:59 UTC, Alexey Kardashevskiy wrote:
> The IODA2 specification says that a 64 DMA address cannot use top 4 bits
> (3 are reserved and one is a "TVE select"); bottom page_shift bits
> cannot be used for multilevel table addressing either.
>
> The existing IODA2 table
On 06/03/17 14:36, Benjamin Herrenschmidt wrote:
> On Mon, 2017-03-06 at 12:28 +1100, Alexey Kardashevskiy wrote:
>> 8192*8192*8192*65536>>40 = 32768TB of addressable memory (but there is no
>> good reason not to use huge pages);
>
> No, 39 bits is half a TB. That's not enough.
Ah. My bad. 55
On Mon, 2017-03-06 at 12:28 +1100, Alexey Kardashevskiy wrote:
> 8192*8192*8192*65536>>40 = 32768TB of addressable memory (but there is no
> good reason not to use huge pages);
No, 39 bits is half a TB. That's not enough.
> 8192*8192*8192*4096>>40 = 2048TB or addressable memory (even with 2
>
On 06/03/17 10:03, Benjamin Herrenschmidt wrote:
> On Mon, 2017-02-27 at 22:00 +1100, Michael Ellerman wrote:
>>> The alternative would be allocating TCE tables as big as PAGE_SIZE
>>> but
>>> only using parts of it but this would complicate a bit bits of code
>>> responsible for overall amount of
On Mon, 2017-02-27 at 22:00 +1100, Michael Ellerman wrote:
> > The alternative would be allocating TCE tables as big as PAGE_SIZE
> > but
> > only using parts of it but this would complicate a bit bits of code
> > responsible for overall amount of memory used for TCE table.
> >
> > Or
On 27/02/17 22:00, Michael Ellerman wrote:
> Alexey Kardashevskiy writes:
>
>> The IODA2 specification says that a 64 DMA address cannot use top 4 bits
>> (3 are reserved and one is a "TVE select"); bottom page_shift bits
>> cannot be used for multilevel table addressing either.
Alexey Kardashevskiy writes:
> The IODA2 specification says that a 64 DMA address cannot use top 4 bits
> (3 are reserved and one is a "TVE select"); bottom page_shift bits
> cannot be used for multilevel table addressing either.
>
> The existing IODA2 table allocation code
On Wed, Feb 22, 2017 at 03:43:59PM +1100, Alexey Kardashevskiy wrote:
>The IODA2 specification says that a 64 DMA address cannot use top 4 bits
>(3 are reserved and one is a "TVE select"); bottom page_shift bits
>cannot be used for multilevel table addressing either.
>
>The existing IODA2 table
The IODA2 specification says that a 64 DMA address cannot use top 4 bits
(3 are reserved and one is a "TVE select"); bottom page_shift bits
cannot be used for multilevel table addressing either.
The existing IODA2 table allocation code aligns the minimum TCE table
size to PAGE_SIZE so in the case