* [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
@ 2022-11-01 7:59 ` Richard Zhu
0 siblings, 0 replies; 12+ messages in thread
From: Richard Zhu @ 2022-11-01 7:59 UTC (permalink / raw)
To: l.stach, bhelgaas, lorenzo.pieralisi
Cc: hongxing.zhu, linux-pci, linux-arm-kernel, linux-kernel, kernel,
linux-imx
The MSI Enable bit controls delivery of MSI interrupts from components
below the Root Port. This bit might lost during the suspend, should be
re-configured during resume.
Encapsulate the MSI enable set into a standalone function, and invoke it
in both probe and resume.
Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
---
drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
1 file changed, 17 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 2616585ca5f8..dba15546075f 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
usleep_range(1000, 10000);
}
+static void pci_imx_set_msi_en(struct dw_pcie *pci)
+{
+ u8 offset;
+ u16 val;
+
+ if (pci_msi_enabled()) {
+ offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
+ dw_pcie_dbi_ro_wr_en(pci);
+ val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
+ val |= PCI_MSI_FLAGS_ENABLE;
+ dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
+ dw_pcie_dbi_ro_wr_dis(pci);
+ }
+}
+
static int imx6_pcie_suspend_noirq(struct device *dev)
{
struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
@@ -1073,6 +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
if (imx6_pcie->link_is_up)
imx6_pcie_start_link(imx6_pcie->pci);
+ pci_imx_set_msi_en(imx6_pcie->pci);
return 0;
}
@@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct platform_device *pdev)
struct resource *dbi_base;
struct device_node *node = dev->of_node;
int ret;
- u16 val;
imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
if (!imx6_pcie)
@@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct platform_device *pdev)
if (ret < 0)
return ret;
- if (pci_msi_enabled()) {
- u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
- val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
- val |= PCI_MSI_FLAGS_ENABLE;
- dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
- }
+ pci_imx_set_msi_en(pci);
return 0;
}
--
2.25.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
2022-11-01 7:59 ` Richard Zhu
@ 2022-11-02 23:10 ` Bjorn Helgaas
-1 siblings, 0 replies; 12+ messages in thread
From: Bjorn Helgaas @ 2022-11-02 23:10 UTC (permalink / raw)
To: Richard Zhu
Cc: l.stach, bhelgaas, lorenzo.pieralisi, linux-pci,
linux-arm-kernel, linux-kernel, kernel, linux-imx
On Tue, Nov 01, 2022 at 03:59:55PM +0800, Richard Zhu wrote:
> The MSI Enable bit controls delivery of MSI interrupts from components
> below the Root Port. This bit might lost during the suspend, should be
> re-configured during resume.
Just out of curiosity, why would this bit "get lost" during suspend?
Don't the normal save and restore in the suspend/resume paths take
care of this? Are there other bits that might get lost?
> Encapsulate the MSI enable set into a standalone function, and invoke it
> in both probe and resume.
>
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> ---
> drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> 1 file changed, 17 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 2616585ca5f8..dba15546075f 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
> usleep_range(1000, 10000);
> }
>
> +static void pci_imx_set_msi_en(struct dw_pcie *pci)
> +{
> + u8 offset;
> + u16 val;
> +
> + if (pci_msi_enabled()) {
> + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> + dw_pcie_dbi_ro_wr_en(pci);
> + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> + val |= PCI_MSI_FLAGS_ENABLE;
> + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> + dw_pcie_dbi_ro_wr_dis(pci);
> + }
> +}
> +
> static int imx6_pcie_suspend_noirq(struct device *dev)
> {
> struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
> @@ -1073,6 +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> if (imx6_pcie->link_is_up)
> imx6_pcie_start_link(imx6_pcie->pci);
>
> + pci_imx_set_msi_en(imx6_pcie->pci);
> return 0;
> }
>
> @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct platform_device *pdev)
> struct resource *dbi_base;
> struct device_node *node = dev->of_node;
> int ret;
> - u16 val;
>
> imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> if (!imx6_pcie)
> @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct platform_device *pdev)
> if (ret < 0)
> return ret;
>
> - if (pci_msi_enabled()) {
> - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> - val |= PCI_MSI_FLAGS_ENABLE;
> - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> - }
> + pci_imx_set_msi_en(pci);
>
> return 0;
> }
> --
> 2.25.1
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
@ 2022-11-02 23:10 ` Bjorn Helgaas
0 siblings, 0 replies; 12+ messages in thread
From: Bjorn Helgaas @ 2022-11-02 23:10 UTC (permalink / raw)
To: Richard Zhu
Cc: l.stach, bhelgaas, lorenzo.pieralisi, linux-pci,
linux-arm-kernel, linux-kernel, kernel, linux-imx
On Tue, Nov 01, 2022 at 03:59:55PM +0800, Richard Zhu wrote:
> The MSI Enable bit controls delivery of MSI interrupts from components
> below the Root Port. This bit might lost during the suspend, should be
> re-configured during resume.
Just out of curiosity, why would this bit "get lost" during suspend?
Don't the normal save and restore in the suspend/resume paths take
care of this? Are there other bits that might get lost?
> Encapsulate the MSI enable set into a standalone function, and invoke it
> in both probe and resume.
>
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> ---
> drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> 1 file changed, 17 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 2616585ca5f8..dba15546075f 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
> usleep_range(1000, 10000);
> }
>
> +static void pci_imx_set_msi_en(struct dw_pcie *pci)
> +{
> + u8 offset;
> + u16 val;
> +
> + if (pci_msi_enabled()) {
> + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> + dw_pcie_dbi_ro_wr_en(pci);
> + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> + val |= PCI_MSI_FLAGS_ENABLE;
> + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> + dw_pcie_dbi_ro_wr_dis(pci);
> + }
> +}
> +
> static int imx6_pcie_suspend_noirq(struct device *dev)
> {
> struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
> @@ -1073,6 +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> if (imx6_pcie->link_is_up)
> imx6_pcie_start_link(imx6_pcie->pci);
>
> + pci_imx_set_msi_en(imx6_pcie->pci);
> return 0;
> }
>
> @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct platform_device *pdev)
> struct resource *dbi_base;
> struct device_node *node = dev->of_node;
> int ret;
> - u16 val;
>
> imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> if (!imx6_pcie)
> @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct platform_device *pdev)
> if (ret < 0)
> return ret;
>
> - if (pci_msi_enabled()) {
> - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> - val |= PCI_MSI_FLAGS_ENABLE;
> - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> - }
> + pci_imx_set_msi_en(pci);
>
> return 0;
> }
> --
> 2.25.1
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 12+ messages in thread* RE: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
2022-11-02 23:10 ` Bjorn Helgaas
@ 2022-11-03 6:26 ` Hongxing Zhu
-1 siblings, 0 replies; 12+ messages in thread
From: Hongxing Zhu @ 2022-11-03 6:26 UTC (permalink / raw)
To: Bjorn Helgaas
Cc: l.stach, bhelgaas, lorenzo.pieralisi, linux-pci,
linux-arm-kernel, linux-kernel, kernel, dl-linux-imx
> -----Original Message-----
> From: Bjorn Helgaas <helgaas@kernel.org>
> Sent: 2022年11月3日 7:11
> To: Hongxing Zhu <hongxing.zhu@nxp.com>
> Cc: l.stach@pengutronix.de; bhelgaas@google.com;
> lorenzo.pieralisi@arm.com; linux-pci@vger.kernel.org;
> linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
>
> On Tue, Nov 01, 2022 at 03:59:55PM +0800, Richard Zhu wrote:
> > The MSI Enable bit controls delivery of MSI interrupts from components
> > below the Root Port. This bit might lost during the suspend, should be
> > re-configured during resume.
>
> Just out of curiosity, why would this bit "get lost" during suspend?
>
> Don't the normal save and restore in the suspend/resume paths take care of
> this? Are there other bits that might get lost?
Hi Bjorn:
Thanks for your care.
The controller might be reset to the known stat during the
re-initialization in the resume path, I think.
dw_pcie_setup_rc() configures most of the controller setting during resume.
It seems that this bit is i.MX PCIe special, should be configured in both the
probe and suspend/resume.
Best Regards
Richard Zhu
>
> > Encapsulate the MSI enable set into a standalone function, and invoke
> > it in both probe and resume.
> >
> > Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> > ---
> > drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> > 1 file changed, 17 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> > b/drivers/pci/controller/dwc/pci-imx6.c
> > index 2616585ca5f8..dba15546075f 100644
> > --- a/drivers/pci/controller/dwc/pci-imx6.c
> > +++ b/drivers/pci/controller/dwc/pci-imx6.c
> > @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct
> imx6_pcie *imx6_pcie)
> > usleep_range(1000, 10000);
> > }
> >
> > +static void pci_imx_set_msi_en(struct dw_pcie *pci) {
> > + u8 offset;
> > + u16 val;
> > +
> > + if (pci_msi_enabled()) {
> > + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > + dw_pcie_dbi_ro_wr_en(pci);
> > + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > + val |= PCI_MSI_FLAGS_ENABLE;
> > + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > + dw_pcie_dbi_ro_wr_dis(pci);
> > + }
> > +}
> > +
> > static int imx6_pcie_suspend_noirq(struct device *dev) {
> > struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); @@ -1073,6
> > +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> > if (imx6_pcie->link_is_up)
> > imx6_pcie_start_link(imx6_pcie->pci);
> >
> > + pci_imx_set_msi_en(imx6_pcie->pci);
> > return 0;
> > }
> >
> > @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct platform_device
> *pdev)
> > struct resource *dbi_base;
> > struct device_node *node = dev->of_node;
> > int ret;
> > - u16 val;
> >
> > imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> > if (!imx6_pcie)
> > @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct
> platform_device *pdev)
> > if (ret < 0)
> > return ret;
> >
> > - if (pci_msi_enabled()) {
> > - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > - val |= PCI_MSI_FLAGS_ENABLE;
> > - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > - }
> > + pci_imx_set_msi_en(pci);
> >
> > return 0;
> > }
> > --
> > 2.25.1
> >
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel@lists.infradead.org
> > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists
> > .infradead.org%2Fmailman%2Flistinfo%2Flinux-arm-kernel&data=05%7
> C0
> >
> 1%7Chongxing.zhu%40nxp.com%7C4454f7f5d1d0438d009908dabd27767e%
> 7C686ea1
> >
> d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638030274437186510%7CUnk
> nown%7CTW
> >
> FpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXV
> CI6
> >
> Mn0%3D%7C3000%7C%7C%7C&sdata=gfiPPlezSSocyNTpq0oKnk5rwwm
> hpmWCszaHa
> > YWLhoI%3D&reserved=0
^ permalink raw reply [flat|nested] 12+ messages in thread* RE: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
@ 2022-11-03 6:26 ` Hongxing Zhu
0 siblings, 0 replies; 12+ messages in thread
From: Hongxing Zhu @ 2022-11-03 6:26 UTC (permalink / raw)
To: Bjorn Helgaas
Cc: l.stach, bhelgaas, lorenzo.pieralisi, linux-pci,
linux-arm-kernel, linux-kernel, kernel, dl-linux-imx
> -----Original Message-----
> From: Bjorn Helgaas <helgaas@kernel.org>
> Sent: 2022年11月3日 7:11
> To: Hongxing Zhu <hongxing.zhu@nxp.com>
> Cc: l.stach@pengutronix.de; bhelgaas@google.com;
> lorenzo.pieralisi@arm.com; linux-pci@vger.kernel.org;
> linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
>
> On Tue, Nov 01, 2022 at 03:59:55PM +0800, Richard Zhu wrote:
> > The MSI Enable bit controls delivery of MSI interrupts from components
> > below the Root Port. This bit might lost during the suspend, should be
> > re-configured during resume.
>
> Just out of curiosity, why would this bit "get lost" during suspend?
>
> Don't the normal save and restore in the suspend/resume paths take care of
> this? Are there other bits that might get lost?
Hi Bjorn:
Thanks for your care.
The controller might be reset to the known stat during the
re-initialization in the resume path, I think.
dw_pcie_setup_rc() configures most of the controller setting during resume.
It seems that this bit is i.MX PCIe special, should be configured in both the
probe and suspend/resume.
Best Regards
Richard Zhu
>
> > Encapsulate the MSI enable set into a standalone function, and invoke
> > it in both probe and resume.
> >
> > Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> > ---
> > drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> > 1 file changed, 17 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> > b/drivers/pci/controller/dwc/pci-imx6.c
> > index 2616585ca5f8..dba15546075f 100644
> > --- a/drivers/pci/controller/dwc/pci-imx6.c
> > +++ b/drivers/pci/controller/dwc/pci-imx6.c
> > @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct
> imx6_pcie *imx6_pcie)
> > usleep_range(1000, 10000);
> > }
> >
> > +static void pci_imx_set_msi_en(struct dw_pcie *pci) {
> > + u8 offset;
> > + u16 val;
> > +
> > + if (pci_msi_enabled()) {
> > + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > + dw_pcie_dbi_ro_wr_en(pci);
> > + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > + val |= PCI_MSI_FLAGS_ENABLE;
> > + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > + dw_pcie_dbi_ro_wr_dis(pci);
> > + }
> > +}
> > +
> > static int imx6_pcie_suspend_noirq(struct device *dev) {
> > struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); @@ -1073,6
> > +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> > if (imx6_pcie->link_is_up)
> > imx6_pcie_start_link(imx6_pcie->pci);
> >
> > + pci_imx_set_msi_en(imx6_pcie->pci);
> > return 0;
> > }
> >
> > @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct platform_device
> *pdev)
> > struct resource *dbi_base;
> > struct device_node *node = dev->of_node;
> > int ret;
> > - u16 val;
> >
> > imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> > if (!imx6_pcie)
> > @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct
> platform_device *pdev)
> > if (ret < 0)
> > return ret;
> >
> > - if (pci_msi_enabled()) {
> > - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > - val |= PCI_MSI_FLAGS_ENABLE;
> > - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > - }
> > + pci_imx_set_msi_en(pci);
> >
> > return 0;
> > }
> > --
> > 2.25.1
> >
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel@lists.infradead.org
> > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists
> > .infradead.org%2Fmailman%2Flistinfo%2Flinux-arm-kernel&data=05%7
> C0
> >
> 1%7Chongxing.zhu%40nxp.com%7C4454f7f5d1d0438d009908dabd27767e%
> 7C686ea1
> >
> d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638030274437186510%7CUnk
> nown%7CTW
> >
> FpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXV
> CI6
> >
> Mn0%3D%7C3000%7C%7C%7C&sdata=gfiPPlezSSocyNTpq0oKnk5rwwm
> hpmWCszaHa
> > YWLhoI%3D&reserved=0
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 12+ messages in thread
* RE: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
2022-11-01 7:59 ` Richard Zhu
@ 2022-11-25 2:07 ` Hongxing Zhu
-1 siblings, 0 replies; 12+ messages in thread
From: Hongxing Zhu @ 2022-11-25 2:07 UTC (permalink / raw)
To: Hongxing Zhu, l.stach, bhelgaas, lorenzo.pieralisi
Cc: linux-pci, linux-arm-kernel, linux-kernel, kernel, dl-linux-imx
Friendly ping.
Anymore comments are very appreciated.
BTW, I had verified on i.MX7D/i.MX6QP platforms that MSI wouldn’t be functional
after resume without this patch.
Best Regards
Richard Zhu
> -----Original Message-----
> From: Richard Zhu <hongxing.zhu@nxp.com>
> Sent: 2022年11月1日 16:00
> To: l.stach@pengutronix.de; bhelgaas@google.com;
> lorenzo.pieralisi@arm.com
> Cc: Hongxing Zhu <hongxing.zhu@nxp.com>; linux-pci@vger.kernel.org;
> linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>
> Subject: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
>
> The MSI Enable bit controls delivery of MSI interrupts from components below
> the Root Port. This bit might lost during the suspend, should be re-configured
> during resume.
>
> Encapsulate the MSI enable set into a standalone function, and invoke it in
> both probe and resume.
>
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> ---
> drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> 1 file changed, 17 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> b/drivers/pci/controller/dwc/pci-imx6.c
> index 2616585ca5f8..dba15546075f 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct
> imx6_pcie *imx6_pcie)
> usleep_range(1000, 10000);
> }
>
> +static void pci_imx_set_msi_en(struct dw_pcie *pci) {
> + u8 offset;
> + u16 val;
> +
> + if (pci_msi_enabled()) {
> + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> + dw_pcie_dbi_ro_wr_en(pci);
> + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> + val |= PCI_MSI_FLAGS_ENABLE;
> + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> + dw_pcie_dbi_ro_wr_dis(pci);
> + }
> +}
> +
> static int imx6_pcie_suspend_noirq(struct device *dev) {
> struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); @@ -1073,6
> +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> if (imx6_pcie->link_is_up)
> imx6_pcie_start_link(imx6_pcie->pci);
>
> + pci_imx_set_msi_en(imx6_pcie->pci);
> return 0;
> }
>
> @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct platform_device
> *pdev)
> struct resource *dbi_base;
> struct device_node *node = dev->of_node;
> int ret;
> - u16 val;
>
> imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> if (!imx6_pcie)
> @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct platform_device
> *pdev)
> if (ret < 0)
> return ret;
>
> - if (pci_msi_enabled()) {
> - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> - val |= PCI_MSI_FLAGS_ENABLE;
> - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> - }
> + pci_imx_set_msi_en(pci);
>
> return 0;
> }
> --
> 2.25.1
^ permalink raw reply [flat|nested] 12+ messages in thread* RE: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
@ 2022-11-25 2:07 ` Hongxing Zhu
0 siblings, 0 replies; 12+ messages in thread
From: Hongxing Zhu @ 2022-11-25 2:07 UTC (permalink / raw)
To: Hongxing Zhu, l.stach, bhelgaas, lorenzo.pieralisi
Cc: linux-pci, linux-arm-kernel, linux-kernel, kernel, dl-linux-imx
Friendly ping.
Anymore comments are very appreciated.
BTW, I had verified on i.MX7D/i.MX6QP platforms that MSI wouldn’t be functional
after resume without this patch.
Best Regards
Richard Zhu
> -----Original Message-----
> From: Richard Zhu <hongxing.zhu@nxp.com>
> Sent: 2022年11月1日 16:00
> To: l.stach@pengutronix.de; bhelgaas@google.com;
> lorenzo.pieralisi@arm.com
> Cc: Hongxing Zhu <hongxing.zhu@nxp.com>; linux-pci@vger.kernel.org;
> linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>
> Subject: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
>
> The MSI Enable bit controls delivery of MSI interrupts from components below
> the Root Port. This bit might lost during the suspend, should be re-configured
> during resume.
>
> Encapsulate the MSI enable set into a standalone function, and invoke it in
> both probe and resume.
>
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> ---
> drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> 1 file changed, 17 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> b/drivers/pci/controller/dwc/pci-imx6.c
> index 2616585ca5f8..dba15546075f 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct
> imx6_pcie *imx6_pcie)
> usleep_range(1000, 10000);
> }
>
> +static void pci_imx_set_msi_en(struct dw_pcie *pci) {
> + u8 offset;
> + u16 val;
> +
> + if (pci_msi_enabled()) {
> + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> + dw_pcie_dbi_ro_wr_en(pci);
> + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> + val |= PCI_MSI_FLAGS_ENABLE;
> + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> + dw_pcie_dbi_ro_wr_dis(pci);
> + }
> +}
> +
> static int imx6_pcie_suspend_noirq(struct device *dev) {
> struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); @@ -1073,6
> +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> if (imx6_pcie->link_is_up)
> imx6_pcie_start_link(imx6_pcie->pci);
>
> + pci_imx_set_msi_en(imx6_pcie->pci);
> return 0;
> }
>
> @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct platform_device
> *pdev)
> struct resource *dbi_base;
> struct device_node *node = dev->of_node;
> int ret;
> - u16 val;
>
> imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> if (!imx6_pcie)
> @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct platform_device
> *pdev)
> if (ret < 0)
> return ret;
>
> - if (pci_msi_enabled()) {
> - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> - val |= PCI_MSI_FLAGS_ENABLE;
> - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> - }
> + pci_imx_set_msi_en(pci);
>
> return 0;
> }
> --
> 2.25.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
2022-11-25 2:07 ` Hongxing Zhu
@ 2022-11-25 10:19 ` Lucas Stach
-1 siblings, 0 replies; 12+ messages in thread
From: Lucas Stach @ 2022-11-25 10:19 UTC (permalink / raw)
To: Hongxing Zhu, bhelgaas, lorenzo.pieralisi
Cc: linux-pci, linux-arm-kernel, linux-kernel, kernel, dl-linux-imx
Am Freitag, dem 25.11.2022 um 02:07 +0000 schrieb Hongxing Zhu:
> Friendly ping.
> Anymore comments are very appreciated.
>
> BTW, I had verified on i.MX7D/i.MX6QP platforms that MSI wouldn’t be functional
> after resume without this patch.
Instead of playing whack-a-mole and restoring individual config setting
after resume, shouldn't we just do a pci_save_state() on suspend and
then restore the complete config by calling pci_restore_state() on
resume?
Regards,
Lucas
>
> Best Regards
> Richard Zhu
>
> > -----Original Message-----
> > From: Richard Zhu <hongxing.zhu@nxp.com>
> > Sent: 2022年11月1日 16:00
> > To: l.stach@pengutronix.de; bhelgaas@google.com;
> > lorenzo.pieralisi@arm.com
> > Cc: Hongxing Zhu <hongxing.zhu@nxp.com>; linux-pci@vger.kernel.org;
> > linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> > kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>
> > Subject: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
> >
> > The MSI Enable bit controls delivery of MSI interrupts from components below
> > the Root Port. This bit might lost during the suspend, should be re-configured
> > during resume.
> >
> > Encapsulate the MSI enable set into a standalone function, and invoke it in
> > both probe and resume.
> >
> > Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> > ---
> > drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> > 1 file changed, 17 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> > b/drivers/pci/controller/dwc/pci-imx6.c
> > index 2616585ca5f8..dba15546075f 100644
> > --- a/drivers/pci/controller/dwc/pci-imx6.c
> > +++ b/drivers/pci/controller/dwc/pci-imx6.c
> > @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct
> > imx6_pcie *imx6_pcie)
> > usleep_range(1000, 10000);
> > }
> >
> > +static void pci_imx_set_msi_en(struct dw_pcie *pci) {
> > + u8 offset;
> > + u16 val;
> > +
> > + if (pci_msi_enabled()) {
> > + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > + dw_pcie_dbi_ro_wr_en(pci);
> > + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > + val |= PCI_MSI_FLAGS_ENABLE;
> > + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > + dw_pcie_dbi_ro_wr_dis(pci);
> > + }
> > +}
> > +
> > static int imx6_pcie_suspend_noirq(struct device *dev) {
> > struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); @@ -1073,6
> > +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> > if (imx6_pcie->link_is_up)
> > imx6_pcie_start_link(imx6_pcie->pci);
> >
> > + pci_imx_set_msi_en(imx6_pcie->pci);
> > return 0;
> > }
> >
> > @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct platform_device
> > *pdev)
> > struct resource *dbi_base;
> > struct device_node *node = dev->of_node;
> > int ret;
> > - u16 val;
> >
> > imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> > if (!imx6_pcie)
> > @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct platform_device
> > *pdev)
> > if (ret < 0)
> > return ret;
> >
> > - if (pci_msi_enabled()) {
> > - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > - val |= PCI_MSI_FLAGS_ENABLE;
> > - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > - }
> > + pci_imx_set_msi_en(pci);
> >
> > return 0;
> > }
> > --
> > 2.25.1
>
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
@ 2022-11-25 10:19 ` Lucas Stach
0 siblings, 0 replies; 12+ messages in thread
From: Lucas Stach @ 2022-11-25 10:19 UTC (permalink / raw)
To: Hongxing Zhu, bhelgaas, lorenzo.pieralisi
Cc: linux-pci, linux-arm-kernel, linux-kernel, kernel, dl-linux-imx
Am Freitag, dem 25.11.2022 um 02:07 +0000 schrieb Hongxing Zhu:
> Friendly ping.
> Anymore comments are very appreciated.
>
> BTW, I had verified on i.MX7D/i.MX6QP platforms that MSI wouldn’t be functional
> after resume without this patch.
Instead of playing whack-a-mole and restoring individual config setting
after resume, shouldn't we just do a pci_save_state() on suspend and
then restore the complete config by calling pci_restore_state() on
resume?
Regards,
Lucas
>
> Best Regards
> Richard Zhu
>
> > -----Original Message-----
> > From: Richard Zhu <hongxing.zhu@nxp.com>
> > Sent: 2022年11月1日 16:00
> > To: l.stach@pengutronix.de; bhelgaas@google.com;
> > lorenzo.pieralisi@arm.com
> > Cc: Hongxing Zhu <hongxing.zhu@nxp.com>; linux-pci@vger.kernel.org;
> > linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> > kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>
> > Subject: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
> >
> > The MSI Enable bit controls delivery of MSI interrupts from components below
> > the Root Port. This bit might lost during the suspend, should be re-configured
> > during resume.
> >
> > Encapsulate the MSI enable set into a standalone function, and invoke it in
> > both probe and resume.
> >
> > Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> > ---
> > drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> > 1 file changed, 17 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> > b/drivers/pci/controller/dwc/pci-imx6.c
> > index 2616585ca5f8..dba15546075f 100644
> > --- a/drivers/pci/controller/dwc/pci-imx6.c
> > +++ b/drivers/pci/controller/dwc/pci-imx6.c
> > @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct
> > imx6_pcie *imx6_pcie)
> > usleep_range(1000, 10000);
> > }
> >
> > +static void pci_imx_set_msi_en(struct dw_pcie *pci) {
> > + u8 offset;
> > + u16 val;
> > +
> > + if (pci_msi_enabled()) {
> > + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > + dw_pcie_dbi_ro_wr_en(pci);
> > + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > + val |= PCI_MSI_FLAGS_ENABLE;
> > + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > + dw_pcie_dbi_ro_wr_dis(pci);
> > + }
> > +}
> > +
> > static int imx6_pcie_suspend_noirq(struct device *dev) {
> > struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); @@ -1073,6
> > +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> > if (imx6_pcie->link_is_up)
> > imx6_pcie_start_link(imx6_pcie->pci);
> >
> > + pci_imx_set_msi_en(imx6_pcie->pci);
> > return 0;
> > }
> >
> > @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct platform_device
> > *pdev)
> > struct resource *dbi_base;
> > struct device_node *node = dev->of_node;
> > int ret;
> > - u16 val;
> >
> > imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> > if (!imx6_pcie)
> > @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct platform_device
> > *pdev)
> > if (ret < 0)
> > return ret;
> >
> > - if (pci_msi_enabled()) {
> > - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > - val |= PCI_MSI_FLAGS_ENABLE;
> > - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > - }
> > + pci_imx_set_msi_en(pci);
> >
> > return 0;
> > }
> > --
> > 2.25.1
>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 12+ messages in thread* RE: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
2022-11-25 10:19 ` Lucas Stach
@ 2022-11-28 3:45 ` Hongxing Zhu
-1 siblings, 0 replies; 12+ messages in thread
From: Hongxing Zhu @ 2022-11-28 3:45 UTC (permalink / raw)
To: Lucas Stach, bhelgaas, lorenzo.pieralisi
Cc: linux-pci, linux-arm-kernel, linux-kernel, kernel, dl-linux-imx
> -----Original Message-----
> From: Lucas Stach <l.stach@pengutronix.de>
> Sent: 2022年11月25日 18:19
> To: Hongxing Zhu <hongxing.zhu@nxp.com>; bhelgaas@google.com;
> lorenzo.pieralisi@arm.com
> Cc: linux-pci@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> linux-kernel@vger.kernel.org; kernel@pengutronix.de; dl-linux-imx
> <linux-imx@nxp.com>
> Subject: Re: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
>
> Am Freitag, dem 25.11.2022 um 02:07 +0000 schrieb Hongxing Zhu:
> > Friendly ping.
> > Anymore comments are very appreciated.
> >
> > BTW, I had verified on i.MX7D/i.MX6QP platforms that MSI wouldn’t be
> > functional after resume without this patch.
>
> Instead of playing whack-a-mole and restoring individual config setting after
> resume, shouldn't we just do a pci_save_state() on suspend and then restore
> the complete config by calling pci_restore_state() on resume?
>
Hi Lucas:
Thanks for your comments.
Refer to my understanding, only the i.MX PCIe specific configs that might
be lost during suspend/resume should be saved/restored here.
Because that most of the configs had been re-configured in the
suspend/resume paths already.
So, only the PCI_MSI_FLAGS should be saved/restored here, right?
Best Regards
Richard Zhu
> Regards,
> Lucas
>
> >
> > Best Regards
> > Richard Zhu
> >
> > > -----Original Message-----
> > > From: Richard Zhu <hongxing.zhu@nxp.com>
> > > Sent: 2022年11月1日 16:00
> > > To: l.stach@pengutronix.de; bhelgaas@google.com;
> > > lorenzo.pieralisi@arm.com
> > > Cc: Hongxing Zhu <hongxing.zhu@nxp.com>; linux-pci@vger.kernel.org;
> > > linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> > > kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>
> > > Subject: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
> > >
> > > The MSI Enable bit controls delivery of MSI interrupts from
> > > components below the Root Port. This bit might lost during the
> > > suspend, should be re-configured during resume.
> > >
> > > Encapsulate the MSI enable set into a standalone function, and
> > > invoke it in both probe and resume.
> > >
> > > Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> > > ---
> > > drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> > > 1 file changed, 17 insertions(+), 7 deletions(-)
> > >
> > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> > > b/drivers/pci/controller/dwc/pci-imx6.c
> > > index 2616585ca5f8..dba15546075f 100644
> > > --- a/drivers/pci/controller/dwc/pci-imx6.c
> > > +++ b/drivers/pci/controller/dwc/pci-imx6.c
> > > @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct
> > > imx6_pcie *imx6_pcie)
> > > usleep_range(1000, 10000);
> > > }
> > >
> > > +static void pci_imx_set_msi_en(struct dw_pcie *pci) {
> > > + u8 offset;
> > > + u16 val;
> > > +
> > > + if (pci_msi_enabled()) {
> > > + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > > + dw_pcie_dbi_ro_wr_en(pci);
> > > + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > > + val |= PCI_MSI_FLAGS_ENABLE;
> > > + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > > + dw_pcie_dbi_ro_wr_dis(pci);
> > > + }
> > > +}
> > > +
> > > static int imx6_pcie_suspend_noirq(struct device *dev) {
> > > struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); @@ -1073,6
> > > +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> > > if (imx6_pcie->link_is_up)
> > > imx6_pcie_start_link(imx6_pcie->pci);
> > >
> > > + pci_imx_set_msi_en(imx6_pcie->pci);
> > > return 0;
> > > }
> > >
> > > @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct
> > > platform_device
> > > *pdev)
> > > struct resource *dbi_base;
> > > struct device_node *node = dev->of_node;
> > > int ret;
> > > - u16 val;
> > >
> > > imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> > > if (!imx6_pcie)
> > > @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct
> > > platform_device
> > > *pdev)
> > > if (ret < 0)
> > > return ret;
> > >
> > > - if (pci_msi_enabled()) {
> > > - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > > - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > > - val |= PCI_MSI_FLAGS_ENABLE;
> > > - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > > - }
> > > + pci_imx_set_msi_en(pci);
> > >
> > > return 0;
> > > }
> > > --
> > > 2.25.1
> >
>
^ permalink raw reply [flat|nested] 12+ messages in thread* RE: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
@ 2022-11-28 3:45 ` Hongxing Zhu
0 siblings, 0 replies; 12+ messages in thread
From: Hongxing Zhu @ 2022-11-28 3:45 UTC (permalink / raw)
To: Lucas Stach, bhelgaas, lorenzo.pieralisi
Cc: linux-pci, linux-arm-kernel, linux-kernel, kernel, dl-linux-imx
> -----Original Message-----
> From: Lucas Stach <l.stach@pengutronix.de>
> Sent: 2022年11月25日 18:19
> To: Hongxing Zhu <hongxing.zhu@nxp.com>; bhelgaas@google.com;
> lorenzo.pieralisi@arm.com
> Cc: linux-pci@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> linux-kernel@vger.kernel.org; kernel@pengutronix.de; dl-linux-imx
> <linux-imx@nxp.com>
> Subject: Re: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
>
> Am Freitag, dem 25.11.2022 um 02:07 +0000 schrieb Hongxing Zhu:
> > Friendly ping.
> > Anymore comments are very appreciated.
> >
> > BTW, I had verified on i.MX7D/i.MX6QP platforms that MSI wouldn’t be
> > functional after resume without this patch.
>
> Instead of playing whack-a-mole and restoring individual config setting after
> resume, shouldn't we just do a pci_save_state() on suspend and then restore
> the complete config by calling pci_restore_state() on resume?
>
Hi Lucas:
Thanks for your comments.
Refer to my understanding, only the i.MX PCIe specific configs that might
be lost during suspend/resume should be saved/restored here.
Because that most of the configs had been re-configured in the
suspend/resume paths already.
So, only the PCI_MSI_FLAGS should be saved/restored here, right?
Best Regards
Richard Zhu
> Regards,
> Lucas
>
> >
> > Best Regards
> > Richard Zhu
> >
> > > -----Original Message-----
> > > From: Richard Zhu <hongxing.zhu@nxp.com>
> > > Sent: 2022年11月1日 16:00
> > > To: l.stach@pengutronix.de; bhelgaas@google.com;
> > > lorenzo.pieralisi@arm.com
> > > Cc: Hongxing Zhu <hongxing.zhu@nxp.com>; linux-pci@vger.kernel.org;
> > > linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> > > kernel@pengutronix.de; dl-linux-imx <linux-imx@nxp.com>
> > > Subject: [PATCH v1] PCI: imx6: Set MSI enable bit of RC in resume
> > >
> > > The MSI Enable bit controls delivery of MSI interrupts from
> > > components below the Root Port. This bit might lost during the
> > > suspend, should be re-configured during resume.
> > >
> > > Encapsulate the MSI enable set into a standalone function, and
> > > invoke it in both probe and resume.
> > >
> > > Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> > > ---
> > > drivers/pci/controller/dwc/pci-imx6.c | 24 +++++++++++++++++-------
> > > 1 file changed, 17 insertions(+), 7 deletions(-)
> > >
> > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> > > b/drivers/pci/controller/dwc/pci-imx6.c
> > > index 2616585ca5f8..dba15546075f 100644
> > > --- a/drivers/pci/controller/dwc/pci-imx6.c
> > > +++ b/drivers/pci/controller/dwc/pci-imx6.c
> > > @@ -1041,6 +1041,21 @@ static void imx6_pcie_pm_turnoff(struct
> > > imx6_pcie *imx6_pcie)
> > > usleep_range(1000, 10000);
> > > }
> > >
> > > +static void pci_imx_set_msi_en(struct dw_pcie *pci) {
> > > + u8 offset;
> > > + u16 val;
> > > +
> > > + if (pci_msi_enabled()) {
> > > + offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > > + dw_pcie_dbi_ro_wr_en(pci);
> > > + val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > > + val |= PCI_MSI_FLAGS_ENABLE;
> > > + dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > > + dw_pcie_dbi_ro_wr_dis(pci);
> > > + }
> > > +}
> > > +
> > > static int imx6_pcie_suspend_noirq(struct device *dev) {
> > > struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); @@ -1073,6
> > > +1088,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
> > > if (imx6_pcie->link_is_up)
> > > imx6_pcie_start_link(imx6_pcie->pci);
> > >
> > > + pci_imx_set_msi_en(imx6_pcie->pci);
> > > return 0;
> > > }
> > >
> > > @@ -1090,7 +1106,6 @@ static int imx6_pcie_probe(struct
> > > platform_device
> > > *pdev)
> > > struct resource *dbi_base;
> > > struct device_node *node = dev->of_node;
> > > int ret;
> > > - u16 val;
> > >
> > > imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> > > if (!imx6_pcie)
> > > @@ -1282,12 +1297,7 @@ static int imx6_pcie_probe(struct
> > > platform_device
> > > *pdev)
> > > if (ret < 0)
> > > return ret;
> > >
> > > - if (pci_msi_enabled()) {
> > > - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> > > - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> > > - val |= PCI_MSI_FLAGS_ENABLE;
> > > - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> > > - }
> > > + pci_imx_set_msi_en(pci);
> > >
> > > return 0;
> > > }
> > > --
> > > 2.25.1
> >
>
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^ permalink raw reply [flat|nested] 12+ messages in thread