RE: [PATCH v3 02/14] PCI: rcar: Don't allocate extra memory for the MSI capture address

Yoshihiro Shimoda
2021-04-01T11:00:24Z

Hi Lorenzo, Marc,

> From: Lorenzo Pieralisi, Sent: Wednesday, March 31, 2021 12:29 AM
>
> On Tue, Mar 30, 2021 at 04:11:33PM +0100, Marc Zyngier wrote:
> > A long cargo-culted behaviour of PCI drivers is to allocate memory
> > to obtain an address that is fed to the controller as the MSI
> > capture address (i.e. the MSI doorbell).
> >
> > But there is no actual requirement for this address to be RAM.
> > All it needs to be is a suitable aligned address that will
> > *not* be DMA'd to.
> >
> > Since the rcar platform already has a requirement that this
> > address should be in the first 4GB of the physical address space,
> > use the controller's own base address as the capture address.
> >
> > Signed-off-by: Marc Zyngier <maz@kernel.org>
> > ---
> > drivers/pci/controller/pcie-rcar-host.c | 18 +++++++-----------
> > 1 file changed, 7 insertions(+), 11 deletions(-)
>
> Marek, Yoshihiro,
>
> can you test this patch please and report back ? It is not fundamental
> for the rest of the series (ie the rest of the series does not depend on
> it) and we can still merge the series without it but it would be good if
> you can review and test anyway.

I reviewed and tested this patch and it worked correctly.
So,

Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

Best regards,
Yoshihiro Shimoda