2021-12-26 07:56:30

by Jisheng Zhang

[permalink] [raw]
Subject: [PATCH] PCI: tegra194: Remove unnecessary MSI enable reg save and restore

The integrated MSI Receiver enable register is always initialized in
dw_pcie_setup_rc() which is also called in resume code path, so we
don't need to save/restore the enable register during suspend/resume.

Signed-off-by: Jisheng Zhang <[email protected]>
---
drivers/pci/controller/dwc/pcie-tegra194.c | 9 ---------
1 file changed, 9 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 904976913081..678898985319 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -186,8 +186,6 @@
#define N_FTS_VAL 52
#define FTS_VAL 52

-#define PORT_LOGIC_MSI_CTRL_INT_0_EN 0x828
-
#define GEN3_EQ_CONTROL_OFF 0x8a8
#define GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC_SHIFT 8
#define GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC_MASK GENMASK(23, 8)
@@ -2189,9 +2187,6 @@ static int tegra_pcie_dw_suspend_noirq(struct device *dev)
if (!pcie->link_state)
return 0;

- /* Save MSI interrupt vector */
- pcie->msi_ctrl_int = dw_pcie_readl_dbi(&pcie->pci,
- PORT_LOGIC_MSI_CTRL_INT_0_EN);
tegra_pcie_downstream_dev_to_D0(pcie);
tegra_pcie_dw_pme_turnoff(pcie);
tegra_pcie_unconfig_controller(pcie);
@@ -2223,10 +2218,6 @@ static int tegra_pcie_dw_resume_noirq(struct device *dev)
if (ret < 0)
goto fail_host_init;

- /* Restore MSI interrupt vector */
- dw_pcie_writel_dbi(&pcie->pci, PORT_LOGIC_MSI_CTRL_INT_0_EN,
- pcie->msi_ctrl_int);
-
return 0;

fail_host_init:
--
2.34.1



2022-04-08 14:10:08

by Lorenzo Pieralisi

[permalink] [raw]
Subject: Re: [PATCH] PCI: tegra194: Remove unnecessary MSI enable reg save and restore

[+cc Vidya]

On Sun, Dec 26, 2021 at 03:49:10PM +0800, Jisheng Zhang wrote:
> The integrated MSI Receiver enable register is always initialized in
> dw_pcie_setup_rc() which is also called in resume code path, so we
> don't need to save/restore the enable register during suspend/resume.
>
> Signed-off-by: Jisheng Zhang <[email protected]>
> ---
> drivers/pci/controller/dwc/pcie-tegra194.c | 9 ---------
> 1 file changed, 9 deletions(-)

Need an ACK from Nvidia folks.

Lorenzo

> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
> index 904976913081..678898985319 100644
> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> @@ -186,8 +186,6 @@
> #define N_FTS_VAL 52
> #define FTS_VAL 52
>
> -#define PORT_LOGIC_MSI_CTRL_INT_0_EN 0x828
> -
> #define GEN3_EQ_CONTROL_OFF 0x8a8
> #define GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC_SHIFT 8
> #define GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC_MASK GENMASK(23, 8)
> @@ -2189,9 +2187,6 @@ static int tegra_pcie_dw_suspend_noirq(struct device *dev)
> if (!pcie->link_state)
> return 0;
>
> - /* Save MSI interrupt vector */
> - pcie->msi_ctrl_int = dw_pcie_readl_dbi(&pcie->pci,
> - PORT_LOGIC_MSI_CTRL_INT_0_EN);
> tegra_pcie_downstream_dev_to_D0(pcie);
> tegra_pcie_dw_pme_turnoff(pcie);
> tegra_pcie_unconfig_controller(pcie);
> @@ -2223,10 +2218,6 @@ static int tegra_pcie_dw_resume_noirq(struct device *dev)
> if (ret < 0)
> goto fail_host_init;
>
> - /* Restore MSI interrupt vector */
> - dw_pcie_writel_dbi(&pcie->pci, PORT_LOGIC_MSI_CTRL_INT_0_EN,
> - pcie->msi_ctrl_int);
> -
> return 0;
>
> fail_host_init:
> --
> 2.34.1
>

2022-04-12 08:57:48

by Vidya Sagar

[permalink] [raw]
Subject: Re: [PATCH] PCI: tegra194: Remove unnecessary MSI enable reg save and restore



On 4/8/2022 5:26 PM, Lorenzo Pieralisi wrote:
> External email: Use caution opening links or attachments
>
>
> [+cc Vidya]
>
> On Sun, Dec 26, 2021 at 03:49:10PM +0800, Jisheng Zhang wrote:
>> The integrated MSI Receiver enable register is always initialized in
>> dw_pcie_setup_rc() which is also called in resume code path, so we
>> don't need to save/restore the enable register during suspend/resume.
>>
>> Signed-off-by: Jisheng Zhang <[email protected]>
>> ---
>> drivers/pci/controller/dwc/pcie-tegra194.c | 9 ---------
>> 1 file changed, 9 deletions(-)
>
> Need an ACK from Nvidia folks.

Looks good to me.
I couldn't verify it on Nvidia platform as we are facing some issue with
suspend/resume sequence.
I'll verify and update as soon as I could get suspend/resume working.

Acked-by: Vidya Sagar <[email protected]>

- Vidya Sagar
>
> Lorenzo
>
>> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
>> index 904976913081..678898985319 100644
>> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
>> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
>> @@ -186,8 +186,6 @@
>> #define N_FTS_VAL 52
>> #define FTS_VAL 52
>>
>> -#define PORT_LOGIC_MSI_CTRL_INT_0_EN 0x828
>> -
>> #define GEN3_EQ_CONTROL_OFF 0x8a8
>> #define GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC_SHIFT 8
>> #define GEN3_EQ_CONTROL_OFF_PSET_REQ_VEC_MASK GENMASK(23, 8)
>> @@ -2189,9 +2187,6 @@ static int tegra_pcie_dw_suspend_noirq(struct device *dev)
>> if (!pcie->link_state)
>> return 0;
>>
>> - /* Save MSI interrupt vector */
>> - pcie->msi_ctrl_int = dw_pcie_readl_dbi(&pcie->pci,
>> - PORT_LOGIC_MSI_CTRL_INT_0_EN);
>> tegra_pcie_downstream_dev_to_D0(pcie);
>> tegra_pcie_dw_pme_turnoff(pcie);
>> tegra_pcie_unconfig_controller(pcie);
>> @@ -2223,10 +2218,6 @@ static int tegra_pcie_dw_resume_noirq(struct device *dev)
>> if (ret < 0)
>> goto fail_host_init;
>>
>> - /* Restore MSI interrupt vector */
>> - dw_pcie_writel_dbi(&pcie->pci, PORT_LOGIC_MSI_CTRL_INT_0_EN,
>> - pcie->msi_ctrl_int);
>> -
>> return 0;
>>
>> fail_host_init:
>> --
>> 2.34.1
>>

2022-04-12 16:41:06

by Lorenzo Pieralisi

[permalink] [raw]
Subject: Re: [PATCH] PCI: tegra194: Remove unnecessary MSI enable reg save and restore

On Sun, 26 Dec 2021 15:49:10 +0800, Jisheng Zhang wrote:
> The integrated MSI Receiver enable register is always initialized in
> dw_pcie_setup_rc() which is also called in resume code path, so we
> don't need to save/restore the enable register during suspend/resume.
>
>

Applied to pci/dwc, thanks!

[1/1] PCI: tegra194: Remove unnecessary MSI enable reg save and restore
https://git.kernel.org/lpieralisi/pci/c/571dda6ca5

Thanks,
Lorenzo