2019-08-20 04:41:43

by Srinath Mannam

[permalink] [raw]
Subject: [PATCH] PCI: Add PCIE ACS quirk for IPROC PAXB

From: Abhinav Ratna <[email protected]>

IPROC PAXB RC doesn't support ACS capabilities and control registers.
Add quirk to have separate IOMMU groups for all EPs and functions connected
to root port, by masking RR/CR/SV/UF bits.

Signed-off-by: Abhinav Ratna <[email protected]>
Signed-off-by: Srinath Mannam <[email protected]>
---
drivers/pci/quirks.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 0f16acc..f9584c0 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4466,6 +4466,21 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags)
return acs_flags ? 0 : 1;
}

+static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags)
+{
+ /*
+ * IPROC PAXB RC doesn't support ACS capabilities and control registers.
+ * Add quirk to to have separate IOMMU groups for all EPs and functions
+ * connected to root port, by masking RR/CR/SV/UF bits.
+ */
+
+ u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV);
+ int ret = acs_flags & ~flags ? 0 : 1;
+
+ return ret;
+}
+
+
static const struct pci_dev_acs_enabled {
u16 vendor;
u16 device;
@@ -4559,6 +4574,7 @@ static const struct pci_dev_acs_enabled {
{ PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs },
{ PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs },
{ PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs },
+ { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs },
{ 0 }
};

--
2.7.4


2019-08-20 15:34:10

by Scott Branden

[permalink] [raw]
Subject: Re: [PATCH] PCI: Add PCIE ACS quirk for IPROC PAXB

Looks good.

On 2019-08-19 9:39 p.m., Srinath Mannam wrote:
> From: Abhinav Ratna <[email protected]>
>
> IPROC PAXB RC doesn't support ACS capabilities and control registers.
> Add quirk to have separate IOMMU groups for all EPs and functions connected
> to root port, by masking RR/CR/SV/UF bits.
>
> Signed-off-by: Abhinav Ratna <[email protected]>
> Signed-off-by: Srinath Mannam <[email protected]>
Acked-by: Scott Branden <[email protected]>
> ---
> drivers/pci/quirks.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 0f16acc..f9584c0 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -4466,6 +4466,21 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags)
> return acs_flags ? 0 : 1;
> }
>
> +static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags)
> +{
> + /*
> + * IPROC PAXB RC doesn't support ACS capabilities and control registers.
> + * Add quirk to to have separate IOMMU groups for all EPs and functions
> + * connected to root port, by masking RR/CR/SV/UF bits.
> + */
> +
> + u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV);
> + int ret = acs_flags & ~flags ? 0 : 1;
> +
> + return ret;
> +}
> +
> +
> static const struct pci_dev_acs_enabled {
> u16 vendor;
> u16 device;
> @@ -4559,6 +4574,7 @@ static const struct pci_dev_acs_enabled {
> { PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs },
> { PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs },
> { PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs },
> + { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs },
> { 0 }
> };
>

2019-09-06 07:44:28

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH] PCI: Add PCIE ACS quirk for IPROC PAXB

[+cc Alex]

On Tue, Aug 20, 2019 at 10:09:45AM +0530, Srinath Mannam wrote:
> From: Abhinav Ratna <[email protected]>
>
> IPROC PAXB RC doesn't support ACS capabilities and control registers.
> Add quirk to have separate IOMMU groups for all EPs and functions connected
> to root port, by masking RR/CR/SV/UF bits.
>
> Signed-off-by: Abhinav Ratna <[email protected]>
> Signed-off-by: Srinath Mannam <[email protected]>

I tentatively applied this to pci/misc with Scott's ack for v5.4.

I tweaked the patch itself to follow the style of similar quirks
(interdiff is below, plus a diff of the commit log). Please make sure
I didn't break it.

I also went out on a limb and reworded the comment to give what I
*think* is the justification for this patch, as opposed to merely a
description of the code. I'm making a lot of assumptions there, so
please confirm that they're correct, or supply alternate justification
if they're not.

> ---
> drivers/pci/quirks.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 0f16acc..f9584c0 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -4466,6 +4466,21 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags)
> return acs_flags ? 0 : 1;
> }
>
> +static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags)
> +{
> + /*
> + * IPROC PAXB RC doesn't support ACS capabilities and control registers.
> + * Add quirk to to have separate IOMMU groups for all EPs and functions
> + * connected to root port, by masking RR/CR/SV/UF bits.
> + */
> +
> + u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV);
> + int ret = acs_flags & ~flags ? 0 : 1;
> +
> + return ret;
> +}
> +
> +
> static const struct pci_dev_acs_enabled {
> u16 vendor;
> u16 device;
> @@ -4559,6 +4574,7 @@ static const struct pci_dev_acs_enabled {
> { PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs },
> { PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs },
> { PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs },
> + { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs },
> { 0 }
> };

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 77c0330ac922..2edbce35e8c5 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4466,21 +4466,19 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags)
return acs_flags ? 0 : 1;
}

-static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags)
+static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags)
{
/*
- * IPROC PAXB RC doesn't support ACS capabilities and control registers.
- * Add quirk to to have separate IOMMU groups for all EPs and functions
- * connected to root port, by masking RR/CR/SV/UF bits.
+ * iProc PAXB Root Ports don't advertise an ACS capability, but
+ * they do not allow peer-to-peer transactions between Root Ports.
+ * Allow each Root Port to be in a separate IOMMU group by masking
+ * SV/RR/CR/UF bits.
*/
+ acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);

- u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV);
- int ret = acs_flags & ~flags ? 0 : 1;
-
- return ret;
+ return acs_flags ? 0 : 1;
}

-
static const struct pci_dev_acs_enabled {
u16 vendor;
u16 device;
@@ -4574,7 +4572,7 @@ static const struct pci_dev_acs_enabled {
{ PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs },
{ PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs },
{ PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs },
- { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs },
+ { PCI_VENDOR_ID_BROADCOM, 0xD714, pci_quirk_brcm_acs },
{ 0 }
};




@@ -1,49 +1,49 @@
-commit b50ae502eff0
+commit 46b2c32df7a4
Author: Abhinav Ratna <[email protected]>
Date: Tue Aug 20 10:09:45 2019 +0530

- PCI: Add PCIE ACS quirk for IPROC PAXB
+ PCI: Add ACS quirk for iProc PAXB

- IPROC PAXB RC doesn't support ACS capabilities and control registers.
- Add quirk to have separate IOMMU groups for all EPs and functions connected
- to root port, by masking RR/CR/SV/UF bits.
+ iProc PAXB Root Ports don't advertise an ACS capability, but they do not
+ allow peer-to-peer transactions between Root Ports. Add an ACS quirk so
+ each Root Port can be in a separate IOMMU group.

+ [bhelgaas: commit log, comment, use common implementation style]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Abhinav Ratna <[email protected]>
Signed-off-by: Srinath Mannam <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
+ Acked-by: Scott Branden <[email protected]>

2019-09-06 07:46:34

by Alex Williamson

[permalink] [raw]
Subject: Re: [PATCH] PCI: Add PCIE ACS quirk for IPROC PAXB

On Thu, 5 Sep 2019 17:26:49 -0500
Bjorn Helgaas <[email protected]> wrote:

> [+cc Alex]
>
> On Tue, Aug 20, 2019 at 10:09:45AM +0530, Srinath Mannam wrote:
> > From: Abhinav Ratna <[email protected]>
> >
> > IPROC PAXB RC doesn't support ACS capabilities and control registers.
> > Add quirk to have separate IOMMU groups for all EPs and functions connected
> > to root port, by masking RR/CR/SV/UF bits.
> >
> > Signed-off-by: Abhinav Ratna <[email protected]>
> > Signed-off-by: Srinath Mannam <[email protected]>
>
> I tentatively applied this to pci/misc with Scott's ack for v5.4.
>
> I tweaked the patch itself to follow the style of similar quirks
> (interdiff is below, plus a diff of the commit log). Please make sure
> I didn't break it.
>
> I also went out on a limb and reworded the comment to give what I
> *think* is the justification for this patch, as opposed to merely a
> description of the code. I'm making a lot of assumptions there, so
> please confirm that they're correct, or supply alternate justification
> if they're not.

Agreed, this really needs to be the vendor vouching for ACS equivalent
functionality, not simply splitting IOMMU groups because it's
inconvenient. Thanks,

Alex

>
> > ---
> > drivers/pci/quirks.c | 16 ++++++++++++++++
> > 1 file changed, 16 insertions(+)
> >
> > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> > index 0f16acc..f9584c0 100644
> > --- a/drivers/pci/quirks.c
> > +++ b/drivers/pci/quirks.c
> > @@ -4466,6 +4466,21 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags)
> > return acs_flags ? 0 : 1;
> > }
> >
> > +static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags)
> > +{
> > + /*
> > + * IPROC PAXB RC doesn't support ACS capabilities and control registers.
> > + * Add quirk to to have separate IOMMU groups for all EPs and functions
> > + * connected to root port, by masking RR/CR/SV/UF bits.
> > + */
> > +
> > + u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV);
> > + int ret = acs_flags & ~flags ? 0 : 1;
> > +
> > + return ret;
> > +}
> > +
> > +
> > static const struct pci_dev_acs_enabled {
> > u16 vendor;
> > u16 device;
> > @@ -4559,6 +4574,7 @@ static const struct pci_dev_acs_enabled {
> > { PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs },
> > { PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs },
> > { PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs },
> > + { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs },
> > { 0 }
> > };
>
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 77c0330ac922..2edbce35e8c5 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -4466,21 +4466,19 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags)
> return acs_flags ? 0 : 1;
> }
>
> -static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags)
> +static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags)
> {
> /*
> - * IPROC PAXB RC doesn't support ACS capabilities and control registers.
> - * Add quirk to to have separate IOMMU groups for all EPs and functions
> - * connected to root port, by masking RR/CR/SV/UF bits.
> + * iProc PAXB Root Ports don't advertise an ACS capability, but
> + * they do not allow peer-to-peer transactions between Root Ports.
> + * Allow each Root Port to be in a separate IOMMU group by masking
> + * SV/RR/CR/UF bits.
> */
> + acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);
>
> - u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV);
> - int ret = acs_flags & ~flags ? 0 : 1;
> -
> - return ret;
> + return acs_flags ? 0 : 1;
> }
>
> -
> static const struct pci_dev_acs_enabled {
> u16 vendor;
> u16 device;
> @@ -4574,7 +4572,7 @@ static const struct pci_dev_acs_enabled {
> { PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs },
> { PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs },
> { PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs },
> - { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs },
> + { PCI_VENDOR_ID_BROADCOM, 0xD714, pci_quirk_brcm_acs },
> { 0 }
> };
>
>
>
>
> @@ -1,49 +1,49 @@
> -commit b50ae502eff0
> +commit 46b2c32df7a4
> Author: Abhinav Ratna <[email protected]>
> Date: Tue Aug 20 10:09:45 2019 +0530
>
> - PCI: Add PCIE ACS quirk for IPROC PAXB
> + PCI: Add ACS quirk for iProc PAXB
>
> - IPROC PAXB RC doesn't support ACS capabilities and control registers.
> - Add quirk to have separate IOMMU groups for all EPs and functions connected
> - to root port, by masking RR/CR/SV/UF bits.
> + iProc PAXB Root Ports don't advertise an ACS capability, but they do not
> + allow peer-to-peer transactions between Root Ports. Add an ACS quirk so
> + each Root Port can be in a separate IOMMU group.
>
> + [bhelgaas: commit log, comment, use common implementation style]
> Link: https://lore.kernel.org/r/[email protected]
> Signed-off-by: Abhinav Ratna <[email protected]>
> Signed-off-by: Srinath Mannam <[email protected]>
> Signed-off-by: Bjorn Helgaas <[email protected]>
> + Acked-by: Scott Branden <[email protected]>
>

2019-09-06 18:54:47

by Srinath Mannam

[permalink] [raw]
Subject: Re: [PATCH] PCI: Add PCIE ACS quirk for IPROC PAXB

Hi Bjorn,

Thank you for the improvements. With the changes, comments and commit
message exactly describes the purpose.
I tested the code changes and works fine.

Thanks again,
Srinath

On Fri, Sep 6, 2019 at 3:56 AM Bjorn Helgaas <[email protected]> wrote:
>
> [+cc Alex]
>
> On Tue, Aug 20, 2019 at 10:09:45AM +0530, Srinath Mannam wrote:
> > From: Abhinav Ratna <[email protected]>
> >
> > IPROC PAXB RC doesn't support ACS capabilities and control registers.
> > Add quirk to have separate IOMMU groups for all EPs and functions connected
> > to root port, by masking RR/CR/SV/UF bits.
> >
> > Signed-off-by: Abhinav Ratna <[email protected]>
> > Signed-off-by: Srinath Mannam <[email protected]>
>
> I tentatively applied this to pci/misc with Scott's ack for v5.4.
>
> I tweaked the patch itself to follow the style of similar quirks
> (interdiff is below, plus a diff of the commit log). Please make sure
> I didn't break it.
>
> I also went out on a limb and reworded the comment to give what I
> *think* is the justification for this patch, as opposed to merely a
> description of the code. I'm making a lot of assumptions there, so
> please confirm that they're correct, or supply alternate justification
> if they're not.
>
> > ---
> > drivers/pci/quirks.c | 16 ++++++++++++++++
> > 1 file changed, 16 insertions(+)
> >
> > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> > index 0f16acc..f9584c0 100644
> > --- a/drivers/pci/quirks.c
> > +++ b/drivers/pci/quirks.c
> > @@ -4466,6 +4466,21 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags)
> > return acs_flags ? 0 : 1;
> > }
> >
> > +static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags)
> > +{
> > + /*
> > + * IPROC PAXB RC doesn't support ACS capabilities and control registers.
> > + * Add quirk to to have separate IOMMU groups for all EPs and functions
> > + * connected to root port, by masking RR/CR/SV/UF bits.
> > + */
> > +
> > + u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV);
> > + int ret = acs_flags & ~flags ? 0 : 1;
> > +
> > + return ret;
> > +}
> > +
> > +
> > static const struct pci_dev_acs_enabled {
> > u16 vendor;
> > u16 device;
> > @@ -4559,6 +4574,7 @@ static const struct pci_dev_acs_enabled {
> > { PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs },
> > { PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs },
> > { PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs },
> > + { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs },
> > { 0 }
> > };
>
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 77c0330ac922..2edbce35e8c5 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -4466,21 +4466,19 @@ static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags)
> return acs_flags ? 0 : 1;
> }
>
> -static int pcie_quirk_brcm_bridge_acs(struct pci_dev *dev, u16 acs_flags)
> +static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags)
> {
> /*
> - * IPROC PAXB RC doesn't support ACS capabilities and control registers.
> - * Add quirk to to have separate IOMMU groups for all EPs and functions
> - * connected to root port, by masking RR/CR/SV/UF bits.
> + * iProc PAXB Root Ports don't advertise an ACS capability, but
> + * they do not allow peer-to-peer transactions between Root Ports.
> + * Allow each Root Port to be in a separate IOMMU group by masking
> + * SV/RR/CR/UF bits.
> */
> + acs_flags &= ~(PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);
>
> - u16 flags = (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV);
> - int ret = acs_flags & ~flags ? 0 : 1;
> -
> - return ret;
> + return acs_flags ? 0 : 1;
> }
>
> -
> static const struct pci_dev_acs_enabled {
> u16 vendor;
> u16 device;
> @@ -4574,7 +4572,7 @@ static const struct pci_dev_acs_enabled {
> { PCI_VENDOR_ID_AMPERE, 0xE00A, pci_quirk_xgene_acs },
> { PCI_VENDOR_ID_AMPERE, 0xE00B, pci_quirk_xgene_acs },
> { PCI_VENDOR_ID_AMPERE, 0xE00C, pci_quirk_xgene_acs },
> - { PCI_VENDOR_ID_BROADCOM, 0xD714, pcie_quirk_brcm_bridge_acs },
> + { PCI_VENDOR_ID_BROADCOM, 0xD714, pci_quirk_brcm_acs },
> { 0 }
> };
>
>
>
>
> @@ -1,49 +1,49 @@
> -commit b50ae502eff0
> +commit 46b2c32df7a4
> Author: Abhinav Ratna <[email protected]>
> Date: Tue Aug 20 10:09:45 2019 +0530
>
> - PCI: Add PCIE ACS quirk for IPROC PAXB
> + PCI: Add ACS quirk for iProc PAXB
>
> - IPROC PAXB RC doesn't support ACS capabilities and control registers.
> - Add quirk to have separate IOMMU groups for all EPs and functions connected
> - to root port, by masking RR/CR/SV/UF bits.
> + iProc PAXB Root Ports don't advertise an ACS capability, but they do not
> + allow peer-to-peer transactions between Root Ports. Add an ACS quirk so
> + each Root Port can be in a separate IOMMU group.
>
> + [bhelgaas: commit log, comment, use common implementation style]
> Link: https://lore.kernel.org/r/[email protected]
> Signed-off-by: Abhinav Ratna <[email protected]>
> Signed-off-by: Srinath Mannam <[email protected]>
> Signed-off-by: Bjorn Helgaas <[email protected]>
> + Acked-by: Scott Branden <[email protected]>
>