RE: (reposting) how to get DMA'able memory within 4GB on 64-bit m achi ne

MEHTA,HIREN (A-SanJose,ex1)
2001-06-28T16:21:10Z

Then why do we have 64-bit dma_addr_t on ia64 ?

-hiren

-----Original Message-----
From: David S. Miller [mailto:davem@redhat.com]
Sent: Wednesday, June 27, 2001 2:26 PM
To: MEHTA,HIREN (A-SanJose,ex1)
Cc: 'linux-kernel@vger.kernel.org'
Subject: Re: (reposting) how to get DMA'able memory within 4GB on 64-bit
machi ne

MEHTA,HIREN (A-SanJose,ex1) writes:
> Is there a way for a driver to ask kernel to
> give DMA'able memory within 4GB ? I read about
> pci_alloc_consistent(). But I could not find out
> whether that guarantees the DMA'able memory to be
> within 4GB or not. Is there any other kernel routine
> that I should call from Driver to get such a memory ?

All of the pci_*() DMA allocation/mapping interfaces give you
32-bit PCI dma addresses.

Later,
David S. Miller
davem@redhat.com