diff mbox series

[v3] PCI: mediatek-gen3: Disable DVFSRC voltage request

Message ID 20211015063602.29058-1-jianjun.wang@mediatek.com (mailing list archive)
State New, archived
Headers show
Series [v3] PCI: mediatek-gen3: Disable DVFSRC voltage request | expand

Commit Message

Jianjun Wang (王建军) Oct. 15, 2021, 6:36 a.m. UTC
When the DVFSRC (dynamic voltage and frequency scaling resource collector)
feature is not implemented, the PCIe hardware will assert a voltage request
signal when exit from the L1 PM Substates to request a specific Vcore
voltage, but cannot receive the voltage ready signal, which will cause
the link to fail to exit the L1 PM Substates.

Disable DVFSRC voltage request by default, we need to find a common way to
enable it in the future.

Fixes: d3bf75b579b9 ("PCI: mediatek-gen3: Add MediaTek Gen3 driver for MT8192")
Signed-off-by: Jianjun Wang <jianjun.wang@mediatek.com>
Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
Tested-by: Qizhong Cheng <qizhong.cheng@mediatek.com>
---
 drivers/pci/controller/pcie-mediatek-gen3.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Jianjun Wang (王建军) Nov. 9, 2021, 6:10 a.m. UTC | #1
Hi Maintainers,

Just gentle ping for this patch, if there is anything I need to modify,
please kindly let me know.

Thanks.

On Fri, 2021-10-15 at 14:36 +0800, Jianjun Wang wrote:
> When the DVFSRC (dynamic voltage and frequency scaling resource
> collector)
> feature is not implemented, the PCIe hardware will assert a voltage
> request
> signal when exit from the L1 PM Substates to request a specific Vcore
> voltage, but cannot receive the voltage ready signal, which will
> cause
> the link to fail to exit the L1 PM Substates.
> 
> Disable DVFSRC voltage request by default, we need to find a common
> way to
> enable it in the future.
> 
> Fixes: d3bf75b579b9 ("PCI: mediatek-gen3: Add MediaTek Gen3 driver
> for MT8192")
> Signed-off-by: Jianjun Wang <jianjun.wang@mediatek.com>
> Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
> Tested-by: Qizhong Cheng <qizhong.cheng@mediatek.com>
> ---
>  drivers/pci/controller/pcie-mediatek-gen3.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c
> b/drivers/pci/controller/pcie-mediatek-gen3.c
> index f3aeb8d4eaca..79fb12fca6a9 100644
> --- a/drivers/pci/controller/pcie-mediatek-gen3.c
> +++ b/drivers/pci/controller/pcie-mediatek-gen3.c
> @@ -79,6 +79,9 @@
>  #define PCIE_ICMD_PM_REG		0x198
>  #define PCIE_TURN_OFF_LINK		BIT(4)
>  
> +#define PCIE_MISC_CTRL_REG		0x348
> +#define PCIE_DISABLE_DVFSRC_VLT_REQ	BIT(1)
> +
>  #define PCIE_TRANS_TABLE_BASE_REG	0x800
>  #define PCIE_ATR_SRC_ADDR_MSB_OFFSET	0x4
>  #define PCIE_ATR_TRSL_ADDR_LSB_OFFSET	0x8
> @@ -297,6 +300,11 @@ static int mtk_pcie_startup_port(struct
> mtk_pcie_port *port)
>  	val &= ~PCIE_INTX_ENABLE;
>  	writel_relaxed(val, port->base + PCIE_INT_ENABLE_REG);
>  
> +	/* Disable DVFSRC voltage request */
> +	val = readl_relaxed(port->base + PCIE_MISC_CTRL_REG);
> +	val |= PCIE_DISABLE_DVFSRC_VLT_REQ;
> +	writel_relaxed(val, port->base + PCIE_MISC_CTRL_REG);
> +
>  	/* Assert all reset signals */
>  	val = readl_relaxed(port->base + PCIE_RST_CTRL_REG);
>  	val |= PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB |
> PCIE_PE_RSTB;
Matthias Brugger Nov. 17, 2021, 5:41 p.m. UTC | #2
On 15/10/2021 08:36, Jianjun Wang wrote:
> When the DVFSRC (dynamic voltage and frequency scaling resource collector)
> feature is not implemented, the PCIe hardware will assert a voltage request
> signal when exit from the L1 PM Substates to request a specific Vcore
> voltage, but cannot receive the voltage ready signal, which will cause
> the link to fail to exit the L1 PM Substates.
> 
> Disable DVFSRC voltage request by default, we need to find a common way to
> enable it in the future.
> 
> Fixes: d3bf75b579b9 ("PCI: mediatek-gen3: Add MediaTek Gen3 driver for MT8192")
> Signed-off-by: Jianjun Wang <jianjun.wang@mediatek.com>
> Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
> Tested-by: Qizhong Cheng <qizhong.cheng@mediatek.com>

Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>

> ---
>   drivers/pci/controller/pcie-mediatek-gen3.c | 8 ++++++++
>   1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
> index f3aeb8d4eaca..79fb12fca6a9 100644
> --- a/drivers/pci/controller/pcie-mediatek-gen3.c
> +++ b/drivers/pci/controller/pcie-mediatek-gen3.c
> @@ -79,6 +79,9 @@
>   #define PCIE_ICMD_PM_REG		0x198
>   #define PCIE_TURN_OFF_LINK		BIT(4)
>   
> +#define PCIE_MISC_CTRL_REG		0x348
> +#define PCIE_DISABLE_DVFSRC_VLT_REQ	BIT(1)
> +
>   #define PCIE_TRANS_TABLE_BASE_REG	0x800
>   #define PCIE_ATR_SRC_ADDR_MSB_OFFSET	0x4
>   #define PCIE_ATR_TRSL_ADDR_LSB_OFFSET	0x8
> @@ -297,6 +300,11 @@ static int mtk_pcie_startup_port(struct mtk_pcie_port *port)
>   	val &= ~PCIE_INTX_ENABLE;
>   	writel_relaxed(val, port->base + PCIE_INT_ENABLE_REG);
>   
> +	/* Disable DVFSRC voltage request */
> +	val = readl_relaxed(port->base + PCIE_MISC_CTRL_REG);
> +	val |= PCIE_DISABLE_DVFSRC_VLT_REQ;
> +	writel_relaxed(val, port->base + PCIE_MISC_CTRL_REG);
> +
>   	/* Assert all reset signals */
>   	val = readl_relaxed(port->base + PCIE_RST_CTRL_REG);
>   	val |= PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB | PCIE_PE_RSTB;
>
Jianjun Wang (王建军) Nov. 29, 2021, 2:51 a.m. UTC | #3
Hi Maintainers,

Just gentle ping for this patch, is there anything I need to do to get
this patch merged?

Thanks.

On Tue, 2021-11-09 at 14:10 +0800, Jianjun Wang wrote:
> 
> On Fri, 2021-10-15 at 14:36 +0800, Jianjun Wang wrote:
> > When the DVFSRC (dynamic voltage and frequency scaling resource
> > collector)
> > feature is not implemented, the PCIe hardware will assert a voltage
> > request
> > signal when exit from the L1 PM Substates to request a specific
> > Vcore
> > voltage, but cannot receive the voltage ready signal, which will
> > cause
> > the link to fail to exit the L1 PM Substates.
> > 
> > Disable DVFSRC voltage request by default, we need to find a common
> > way to
> > enable it in the future.
> > 
> > Fixes: d3bf75b579b9 ("PCI: mediatek-gen3: Add MediaTek Gen3 driver
> > for MT8192")
> > Signed-off-by: Jianjun Wang <jianjun.wang@mediatek.com>
> > Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
> > Tested-by: Qizhong Cheng <qizhong.cheng@mediatek.com>
> > ---
> >  drivers/pci/controller/pcie-mediatek-gen3.c | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c
> > b/drivers/pci/controller/pcie-mediatek-gen3.c
> > index f3aeb8d4eaca..79fb12fca6a9 100644
> > --- a/drivers/pci/controller/pcie-mediatek-gen3.c
> > +++ b/drivers/pci/controller/pcie-mediatek-gen3.c
> > @@ -79,6 +79,9 @@
> >  #define PCIE_ICMD_PM_REG		0x198
> >  #define PCIE_TURN_OFF_LINK		BIT(4)
> >  
> > +#define PCIE_MISC_CTRL_REG		0x348
> > +#define PCIE_DISABLE_DVFSRC_VLT_REQ	BIT(1)
> > +
> >  #define PCIE_TRANS_TABLE_BASE_REG	0x800
> >  #define PCIE_ATR_SRC_ADDR_MSB_OFFSET	0x4
> >  #define PCIE_ATR_TRSL_ADDR_LSB_OFFSET	0x8
> > @@ -297,6 +300,11 @@ static int mtk_pcie_startup_port(struct
> > mtk_pcie_port *port)
> >  	val &= ~PCIE_INTX_ENABLE;
> >  	writel_relaxed(val, port->base + PCIE_INT_ENABLE_REG);
> >  
> > +	/* Disable DVFSRC voltage request */
> > +	val = readl_relaxed(port->base + PCIE_MISC_CTRL_REG);
> > +	val |= PCIE_DISABLE_DVFSRC_VLT_REQ;
> > +	writel_relaxed(val, port->base + PCIE_MISC_CTRL_REG);
> > +
> >  	/* Assert all reset signals */
> >  	val = readl_relaxed(port->base + PCIE_RST_CTRL_REG);
> >  	val |= PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB |
> > PCIE_PE_RSTB;
> 
> _______________________________________________
> Linux-mediatek mailing list
> Linux-mediatek@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-mediatek
Lorenzo Pieralisi Nov. 29, 2021, 12:10 p.m. UTC | #4
On Fri, 15 Oct 2021 14:36:02 +0800, Jianjun Wang wrote:
> When the DVFSRC (dynamic voltage and frequency scaling resource collector)
> feature is not implemented, the PCIe hardware will assert a voltage request
> signal when exit from the L1 PM Substates to request a specific Vcore
> voltage, but cannot receive the voltage ready signal, which will cause
> the link to fail to exit the L1 PM Substates.
> 
> Disable DVFSRC voltage request by default, we need to find a common way to
> enable it in the future.
> 
> [...]

Applied to pci/mediatek-gen3, thanks!

[1/1] PCI: mediatek-gen3: Disable DVFSRC voltage request
      https://git.kernel.org/lpieralisi/pci/c/ab344fd43f

Thanks,
Lorenzo
diff mbox series

Patch

diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
index f3aeb8d4eaca..79fb12fca6a9 100644
--- a/drivers/pci/controller/pcie-mediatek-gen3.c
+++ b/drivers/pci/controller/pcie-mediatek-gen3.c
@@ -79,6 +79,9 @@ 
 #define PCIE_ICMD_PM_REG		0x198
 #define PCIE_TURN_OFF_LINK		BIT(4)
 
+#define PCIE_MISC_CTRL_REG		0x348
+#define PCIE_DISABLE_DVFSRC_VLT_REQ	BIT(1)
+
 #define PCIE_TRANS_TABLE_BASE_REG	0x800
 #define PCIE_ATR_SRC_ADDR_MSB_OFFSET	0x4
 #define PCIE_ATR_TRSL_ADDR_LSB_OFFSET	0x8
@@ -297,6 +300,11 @@  static int mtk_pcie_startup_port(struct mtk_pcie_port *port)
 	val &= ~PCIE_INTX_ENABLE;
 	writel_relaxed(val, port->base + PCIE_INT_ENABLE_REG);
 
+	/* Disable DVFSRC voltage request */
+	val = readl_relaxed(port->base + PCIE_MISC_CTRL_REG);
+	val |= PCIE_DISABLE_DVFSRC_VLT_REQ;
+	writel_relaxed(val, port->base + PCIE_MISC_CTRL_REG);
+
 	/* Assert all reset signals */
 	val = readl_relaxed(port->base + PCIE_RST_CTRL_REG);
 	val |= PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB | PCIE_PE_RSTB;