Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1666472 > unrolled thread

[PATCH kernel 2/3] pci-ioda: Set PCI_BUS_FLAGS_MSI_REMAP for IODA host bridge

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  [PATCH kernel 2/3] pci-ioda: Set PCI_BUS_FLAGS_MSI_REMAP for IODA host bridge Alexey Kardashevskiy <aik@ozlabs.ru> - 2017-06-15 07:50 +0200
    Re: [PATCH kernel 2/3] pci-ioda: Set PCI_BUS_FLAGS_MSI_REMAP for IODA host bridge Michael Ellerman <mpe@ellerman.id.au> - 2017-06-15 11:30 +0200
      Re: [PATCH kernel 2/3] pci-ioda: Set PCI_BUS_FLAGS_MSI_REMAP for  IODA host bridge Benjamin Herrenschmidt <benh@kernel.crashing.org> - 2017-06-15 13:00 +0200

#1666472 — [PATCH kernel 2/3] pci-ioda: Set PCI_BUS_FLAGS_MSI_REMAP for IODA host bridge

From: Yongji Xie <elohimes@gmail.com>

Any IODA host bridge have the capability of IRQ remapping.
So we set PCI_BUS_FLAGS_MSI_REMAP when this kind of host birdge
is detected.

Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
 arch/powerpc/platforms/powernv/pci-ioda.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 283caf1070c9..b6bda1918273 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -3177,6 +3177,12 @@ static void pnv_pci_ioda_fixup(void)
 #endif
 }
 
+int pnv_pci_ioda_root_bridge_prepare(struct pci_host_bridge *bridge)
+{
+	bridge->bus->bus_flags |= PCI_BUS_FLAGS_MSI_REMAP;
+	return 0;
+}
+
 /*
  * Returns the alignment for I/O or memory windows for P2P
  * bridges. That actually depends on how PEs are segmented.
@@ -3861,6 +3867,8 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
 	 */
 	ppc_md.pcibios_fixup = pnv_pci_ioda_fixup;
 
+	ppc_md.pcibios_root_bridge_prepare = pnv_pci_ioda_root_bridge_prepare;
+
 	if (phb->type == PNV_PHB_NPU) {
 		hose->controller_ops = pnv_npu_ioda_controller_ops;
 	} else {
-- 
2.11.0

[toc] | [next] | [standalone]

#1666594

Alexey Kardashevskiy <aik@ozlabs.ru> writes:

> From: Yongji Xie <elohimes@gmail.com>
>
> Any IODA host bridge have the capability of IRQ remapping.
> So we set PCI_BUS_FLAGS_MSI_REMAP when this kind of host birdge
> is detected.

Where's the code that actually enforces this property?

It would be good to have a comment in pnv_pci_ioda_root_bridge_prepare()
(probably), pointing to that code, so that we can remember the
relationship between the two.

cheers

[toc] | [prev] | [next] | [standalone]

#1666656 — Re: [PATCH kernel 2/3] pci-ioda: Set PCI_BUS_FLAGS_MSI_REMAP for IODA host bridge

On Thu, 2017-06-15 at 19:25 +1000, Michael Ellerman wrote:
> Alexey Kardashevskiy <aik@ozlabs.ru> writes:
> 
> > From: Yongji Xie <elohimes@gmail.com>
> > 
> > Any IODA host bridge have the capability of IRQ remapping.
> > So we set PCI_BUS_FLAGS_MSI_REMAP when this kind of host birdge
> > is detected.
> 
> Where's the code that actually enforces this property?
> 
> It would be good to have a comment in pnv_pci_ioda_root_bridge_prepare()
> (probably), pointing to that code, so that we can remember the
> relationship between the two.

Actually it's not so much remapping as:

 - The bridge can enforce that the interrupt is allowed for a given
partition

 - Because the interrupts are handled via the hypervisor, the latter
can do the remapping.

But the effect is the same, so yes we want the flag. On P9 with XIVE
exploitation we also have HW remapping on top.

Cheers,
Ben.

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web