[Skiboot] [PATCH] phb4: Fix TVE encoding for start address

[Benjamin Herrenschmidt]

On Fri, 2017-02-03 at 14:34 +1100, Alistair Popple wrote:
> Do we also need the same fix to hw/phb3.c and hw/npu.c?
> 
> I haven't tested this but it looks reasonable. If I'm not mistaken
> the
> old behaviour would have allowed a PCIe device to access addresses
> below it's allocated PCIe bus address so this just increases
> protection by further restricting device access.

I *think* we always put 0 in there anyway, don't we ?

As for PHB3 and NPU, check the spec to see where the bits are.

> Reviewed-By: Alistair Popple <alistair at popple.id.au>
> 
> On Tue, 3 Jan 2017 06:38:22 PM Frederic Barrat wrote:
> > From the phb4 spec, when encoding the TVE, the pci start address
> > bits
> > 49:24 are encoded in bits TVE[52:53]||[0:23].
> > The mask to select bits 47:24 is incorrectly set. It should be
> > 0xffffff000000, shifted left by 16, i.e. 0xffffff << 40
> > 
> > Signed-off-by: Frederic Barrat <fbarrat at linux.vnet.ibm.com>
> > ---
> > Already discussed with Benh
> > 
> >  hw/phb4.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/hw/phb4.c b/hw/phb4.c
> > index b2723ca..c2c7cc7 100644
> > --- a/hw/phb4.c
> > +++ b/hw/phb4.c
> > @@ -1345,7 +1345,7 @@ static int64_t
> > phb4_map_pe_dma_window_real(struct phb *phb,
> >  		 * and end address bits 49:24 into
> > TVE[54:55]||[24:47]
> >  		 * and set TVE[51]
> >  		 */
> > -		tve  = (pci_start_addr << 16) & (0xffffffull <<
> > 48);
> > +		tve  = (pci_start_addr << 16) & (0xffffffull <<
> > 40);
> >  		tve |= (pci_start_addr >> 38) & (3ull << 10);
> >  		tve |= (end >>  8) & (0xfffffful << 16);
> >  		tve |= (end >> 40) & (3ull << 8);
> >