[v3,4/4] PCI: layerscape: Add suspend/resume for ls1043a

Message ID 20231017193145.3198380-5-Frank.Li@nxp.com
State New
Headers
Series PCI: layerscape: Add suspend/resume support for ls1043 and ls1021 |

Commit Message

Frank Li Oct. 17, 2023, 7:31 p.m. UTC
  ls1043a add suspend/resume support.
Implement ls1043a_pcie_send_turnoff_msg() to send PME_Turn_Off message.
Implement ls1043a_pcie_exit_from_l2() to exit from L2 state.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---

Notes:
    Change from v2 to v3
    - Remove ls_pcie_lut_readl(writel) function
    
    Change from v1 to v2
    - Update subject 'a' to 'A'

 drivers/pci/controller/dwc/pci-layerscape.c | 86 ++++++++++++++++++++-
 1 file changed, 85 insertions(+), 1 deletion(-)
  

Comments

Manivannan Sadhasivam Nov. 2, 2023, 5:39 p.m. UTC | #1
On Tue, Oct 17, 2023 at 03:31:45PM -0400, Frank Li wrote:
> ls1043a add suspend/resume support.
> Implement ls1043a_pcie_send_turnoff_msg() to send PME_Turn_Off message.
> Implement ls1043a_pcie_exit_from_l2() to exit from L2 state.
> 

Please use the suggestion I gave in patch 2/4.

> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> 
> Notes:
>     Change from v2 to v3
>     - Remove ls_pcie_lut_readl(writel) function
>     
>     Change from v1 to v2
>     - Update subject 'a' to 'A'
> 
>  drivers/pci/controller/dwc/pci-layerscape.c | 86 ++++++++++++++++++++-
>  1 file changed, 85 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/dwc/pci-layerscape.c b/drivers/pci/controller/dwc/pci-layerscape.c
> index 4b663b20d8612..9656224960b0c 100644
> --- a/drivers/pci/controller/dwc/pci-layerscape.c
> +++ b/drivers/pci/controller/dwc/pci-layerscape.c
> @@ -41,6 +41,15 @@
>  #define SCFG_PEXSFTRSTCR	0x190
>  #define PEXSR(idx)		BIT(idx)
>  
> +/* LS1043A PEX PME control register */
> +#define SCFG_PEXPMECR		0x144
> +#define PEXPME(idx)		BIT(31 - (idx) * 4)
> +
> +/* LS1043A PEX LUT debug register */
> +#define LS_PCIE_LDBG	0x7fc
> +#define LDBG_SR		BIT(30)
> +#define LDBG_WE		BIT(31)
> +
>  #define PCIE_IATU_NUM		6
>  
>  #define LS_PCIE_DRV_SCFG	BIT(0)
> @@ -227,6 +236,68 @@ static int ls1021a_pcie_exit_from_l2(struct dw_pcie_rp *pp)
>  	return 0;
>  }
>  
> +static void ls1043a_pcie_send_turnoff_msg(struct dw_pcie_rp *pp)
> +{
> +	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> +	struct ls_pcie *pcie = to_ls_pcie(pci);
> +	u32 val;
> +
> +	if (!pcie->scfg) {
> +		dev_dbg(pcie->pci->dev, "SYSCFG is NULL\n");
> +		return;
> +	}

Why scfg is optional for this SoC and not for the other one added in patch 2/4?

> +
> +	/* Send Turn_off message */
> +	regmap_read(pcie->scfg, SCFG_PEXPMECR, &val);
> +	val |= PEXPME(pcie->index);
> +	regmap_write(pcie->scfg, SCFG_PEXPMECR, val);
> +

In my previous review, I asked you to use a common function and just pass the
offsets, as the sequence is same for both the SoCs. But you ignored it :/

> +	/*
> +	 * There is no specific register to check for PME_To_Ack from endpoint.
> +	 * So on the safe side, wait for PCIE_PME_TO_L2_TIMEOUT_US.
> +	 */
> +	mdelay(PCIE_PME_TO_L2_TIMEOUT_US/1000);
> +
> +	/*
> +	 * Layerscape hardware reference manual recommends clearing the PMXMTTURNOFF bit
> +	 * to complete the PME_Turn_Off handshake.
> +	 */
> +	regmap_read(pcie->scfg, SCFG_PEXPMECR, &val);
> +	val &= ~PEXPME(pcie->index);
> +	regmap_write(pcie->scfg, SCFG_PEXPMECR, val);
> +}
> +
> +static int ls1043a_pcie_exit_from_l2(struct dw_pcie_rp *pp)
> +{
> +	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> +	struct ls_pcie *pcie = to_ls_pcie(pci);
> +	u32 val;
> +
> +	/*
> +	 * Only way let PEX module exit L2 is do a software reset.

Same comment applies as patch 2/4.

- Mani
  
Frank Li Nov. 2, 2023, 6:29 p.m. UTC | #2
On Thu, Nov 02, 2023 at 11:09:00PM +0530, Manivannan Sadhasivam wrote:
> On Tue, Oct 17, 2023 at 03:31:45PM -0400, Frank Li wrote:
> > ls1043a add suspend/resume support.
> > Implement ls1043a_pcie_send_turnoff_msg() to send PME_Turn_Off message.
> > Implement ls1043a_pcie_exit_from_l2() to exit from L2 state.
> > 
> 
> Please use the suggestion I gave in patch 2/4.
> 
> > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > ---
> > 
> > Notes:
> >     Change from v2 to v3
> >     - Remove ls_pcie_lut_readl(writel) function
> >     
> >     Change from v1 to v2
> >     - Update subject 'a' to 'A'
> > 
> >  drivers/pci/controller/dwc/pci-layerscape.c | 86 ++++++++++++++++++++-
> >  1 file changed, 85 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/pci/controller/dwc/pci-layerscape.c b/drivers/pci/controller/dwc/pci-layerscape.c
> > index 4b663b20d8612..9656224960b0c 100644
> > --- a/drivers/pci/controller/dwc/pci-layerscape.c
> > +++ b/drivers/pci/controller/dwc/pci-layerscape.c
> > @@ -41,6 +41,15 @@
> >  #define SCFG_PEXSFTRSTCR	0x190
> >  #define PEXSR(idx)		BIT(idx)
> >  
> > +/* LS1043A PEX PME control register */
> > +#define SCFG_PEXPMECR		0x144
> > +#define PEXPME(idx)		BIT(31 - (idx) * 4)
> > +
> > +/* LS1043A PEX LUT debug register */
> > +#define LS_PCIE_LDBG	0x7fc
> > +#define LDBG_SR		BIT(30)
> > +#define LDBG_WE		BIT(31)
> > +
> >  #define PCIE_IATU_NUM		6
> >  
> >  #define LS_PCIE_DRV_SCFG	BIT(0)
> > @@ -227,6 +236,68 @@ static int ls1021a_pcie_exit_from_l2(struct dw_pcie_rp *pp)
> >  	return 0;
> >  }
> >  
> > +static void ls1043a_pcie_send_turnoff_msg(struct dw_pcie_rp *pp)
> > +{
> > +	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> > +	struct ls_pcie *pcie = to_ls_pcie(pci);
> > +	u32 val;
> > +
> > +	if (!pcie->scfg) {
> > +		dev_dbg(pcie->pci->dev, "SYSCFG is NULL\n");
> > +		return;
> > +	}
> 
> Why scfg is optional for this SoC and not for the other one added in patch 2/4?

No, it is not optional for this SoC. This check can be removed as your
previous comments about 2/4.

> 
> > +
> > +	/* Send Turn_off message */
> > +	regmap_read(pcie->scfg, SCFG_PEXPMECR, &val);
> > +	val |= PEXPME(pcie->index);
> > +	regmap_write(pcie->scfg, SCFG_PEXPMECR, val);
> > +
> 
> In my previous review, I asked you to use a common function and just pass the
> offsets, as the sequence is same for both the SoCs. But you ignored it :/
> 

Sorry, I will fixed it at next version. 

> > +	/*
> > +	 * There is no specific register to check for PME_To_Ack from endpoint.
> > +	 * So on the safe side, wait for PCIE_PME_TO_L2_TIMEOUT_US.
> > +	 */
> > +	mdelay(PCIE_PME_TO_L2_TIMEOUT_US/1000);
> > +
> > +	/*
> > +	 * Layerscape hardware reference manual recommends clearing the PMXMTTURNOFF bit
> > +	 * to complete the PME_Turn_Off handshake.
> > +	 */
> > +	regmap_read(pcie->scfg, SCFG_PEXPMECR, &val);
> > +	val &= ~PEXPME(pcie->index);
> > +	regmap_write(pcie->scfg, SCFG_PEXPMECR, val);
> > +}
> > +
> > +static int ls1043a_pcie_exit_from_l2(struct dw_pcie_rp *pp)
> > +{
> > +	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> > +	struct ls_pcie *pcie = to_ls_pcie(pci);
> > +	u32 val;
> > +
> > +	/*
> > +	 * Only way let PEX module exit L2 is do a software reset.
> 
> Same comment applies as patch 2/4.
> 
> - Mani
> 
> -- 
> மணிவண்ணன் சதாசிவம்
  

Patch

diff --git a/drivers/pci/controller/dwc/pci-layerscape.c b/drivers/pci/controller/dwc/pci-layerscape.c
index 4b663b20d8612..9656224960b0c 100644
--- a/drivers/pci/controller/dwc/pci-layerscape.c
+++ b/drivers/pci/controller/dwc/pci-layerscape.c
@@ -41,6 +41,15 @@ 
 #define SCFG_PEXSFTRSTCR	0x190
 #define PEXSR(idx)		BIT(idx)
 
+/* LS1043A PEX PME control register */
+#define SCFG_PEXPMECR		0x144
+#define PEXPME(idx)		BIT(31 - (idx) * 4)
+
+/* LS1043A PEX LUT debug register */
+#define LS_PCIE_LDBG	0x7fc
+#define LDBG_SR		BIT(30)
+#define LDBG_WE		BIT(31)
+
 #define PCIE_IATU_NUM		6
 
 #define LS_PCIE_DRV_SCFG	BIT(0)
@@ -227,6 +236,68 @@  static int ls1021a_pcie_exit_from_l2(struct dw_pcie_rp *pp)
 	return 0;
 }
 
+static void ls1043a_pcie_send_turnoff_msg(struct dw_pcie_rp *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct ls_pcie *pcie = to_ls_pcie(pci);
+	u32 val;
+
+	if (!pcie->scfg) {
+		dev_dbg(pcie->pci->dev, "SYSCFG is NULL\n");
+		return;
+	}
+
+	/* Send Turn_off message */
+	regmap_read(pcie->scfg, SCFG_PEXPMECR, &val);
+	val |= PEXPME(pcie->index);
+	regmap_write(pcie->scfg, SCFG_PEXPMECR, val);
+
+	/*
+	 * There is no specific register to check for PME_To_Ack from endpoint.
+	 * So on the safe side, wait for PCIE_PME_TO_L2_TIMEOUT_US.
+	 */
+	mdelay(PCIE_PME_TO_L2_TIMEOUT_US/1000);
+
+	/*
+	 * Layerscape hardware reference manual recommends clearing the PMXMTTURNOFF bit
+	 * to complete the PME_Turn_Off handshake.
+	 */
+	regmap_read(pcie->scfg, SCFG_PEXPMECR, &val);
+	val &= ~PEXPME(pcie->index);
+	regmap_write(pcie->scfg, SCFG_PEXPMECR, val);
+}
+
+static int ls1043a_pcie_exit_from_l2(struct dw_pcie_rp *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct ls_pcie *pcie = to_ls_pcie(pci);
+	u32 val;
+
+	/*
+	 * Only way let PEX module exit L2 is do a software reset.
+	 * LDBG_WE: allows the user to have write access to the PEXDBG[SR] for both setting and
+	 *	    clearing the soft reset on the PEX module.
+	 * LDBG_SR: When SR is set to 1, the PEX module enters soft reset.
+	 */
+	val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_LDBG);
+	val |= LDBG_WE;
+	ls_pcie_pf_lut_writel(pcie, LS_PCIE_LDBG, val);
+
+	val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_LDBG);
+	val |= LDBG_SR;
+	ls_pcie_pf_lut_writel(pcie, LS_PCIE_LDBG, val);
+
+	val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_LDBG);
+	val &= ~LDBG_SR;
+	ls_pcie_pf_lut_writel(pcie, LS_PCIE_LDBG, val);
+
+	val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_LDBG);
+	val &= ~LDBG_WE;
+	ls_pcie_pf_lut_writel(pcie, LS_PCIE_LDBG, val);
+
+	return 0;
+}
+
 static const struct dw_pcie_host_ops ls_pcie_host_ops = {
 	.host_init = ls_pcie_host_init,
 	.pme_turn_off = ls_pcie_send_turnoff_msg,
@@ -244,6 +315,19 @@  static const struct ls_pcie_drvdata ls1021a_drvdata = {
 	.flags = LS_PCIE_DRV_SCFG,
 };
 
+static const struct dw_pcie_host_ops ls1043a_pcie_host_ops = {
+	.host_init = ls_pcie_host_init,
+	.pme_turn_off = ls1043a_pcie_send_turnoff_msg,
+};
+
+static const struct ls_pcie_drvdata ls1043a_drvdata = {
+	.pf_lut_off = 0x10000,
+	.pm_support = true,
+	.ops = &ls1043a_pcie_host_ops,
+	.exit_from_l2 = ls1043a_pcie_exit_from_l2,
+	.flags = LS_PCIE_DRV_SCFG,
+};
+
 static const struct ls_pcie_drvdata layerscape_drvdata = {
 	.pf_lut_off = 0xc0000,
 	.pm_support = true,
@@ -254,7 +338,7 @@  static const struct of_device_id ls_pcie_of_match[] = {
 	{ .compatible = "fsl,ls1012a-pcie", .data = &layerscape_drvdata },
 	{ .compatible = "fsl,ls1021a-pcie", .data = &ls1021a_drvdata },
 	{ .compatible = "fsl,ls1028a-pcie", .data = &layerscape_drvdata },
-	{ .compatible = "fsl,ls1043a-pcie", .data = &ls1021a_drvdata },
+	{ .compatible = "fsl,ls1043a-pcie", .data = &ls1043a_drvdata },
 	{ .compatible = "fsl,ls1046a-pcie", .data = &layerscape_drvdata },
 	{ .compatible = "fsl,ls2080a-pcie", .data = &layerscape_drvdata },
 	{ .compatible = "fsl,ls2085a-pcie", .data = &layerscape_drvdata },