diff mbox series

[v2,5/6] PCI: dwc: rcar-gen4: Add support for other R-Car Gen4 PCIe controller

Message ID 20240326024540.2336155-6-yoshihiro.shimoda.uh@renesas.com (mailing list archive)
State Superseded
Delegated to: Krzysztof WilczyƄski
Headers show
Series PCI: dwc: rcar-gen4: Add R-Car V4H support | expand

Commit Message

Yoshihiro Shimoda March 26, 2024, 2:45 a.m. UTC
The PCIe controllers of R-Car V4H (r8a779g0) and one more SoC require
different initializing settings than R-Car S4-8 (r8a779f0). So, add
specific functions for them as "renesas,rcar-gen4-pcie{-ep}" compatible.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
---
 drivers/pci/controller/dwc/pcie-rcar-gen4.c | 188 +++++++++++++++++++-
 1 file changed, 187 insertions(+), 1 deletion(-)

Comments

Bjorn Helgaas March 26, 2024, 8:48 p.m. UTC | #1
The subject line should specify which controller(s) this adds support
for.

On Tue, Mar 26, 2024 at 11:45:39AM +0900, Yoshihiro Shimoda wrote:
> The PCIe controllers of R-Car V4H (r8a779g0) and one more SoC require
> different initializing settings than R-Car S4-8 (r8a779f0). So, add
> specific functions for them as "renesas,rcar-gen4-pcie{-ep}" compatible.

I can't tell from this what's being added.  This should say something
like "this driver previously supported r8....  Add support for r8...."
so it's clear what was existing and what is new.

Hmm... the first use of request_firmware() in drivers/pci/.  That
warrants a mention here as it's a pretty significant change.

> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> ---
>  drivers/pci/controller/dwc/pcie-rcar-gen4.c | 188 +++++++++++++++++++-
>  1 file changed, 187 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index a37613dd9ff4..7f3b5e9ca405 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -5,8 +5,10 @@
>   */
>  
>  #include <linux/delay.h>
> +#include <linux/firmware.h>
>  #include <linux/interrupt.h>
>  #include <linux/io.h>
> +#include <linux/iopoll.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
>  #include <linux/pci.h>
> @@ -20,9 +22,10 @@
>  /* Renesas-specific */
>  /* PCIe Mode Setting Register 0 */
>  #define PCIEMSR0		0x0000
> -#define BIFUR_MOD_SET_ON	BIT(0)
> +#define APP_SRIS_MODE		BIT(6)
>  #define DEVICE_TYPE_EP		0
>  #define DEVICE_TYPE_RC		BIT(4)
> +#define BIFUR_MOD_SET_ON	BIT(0)
>  
>  /* PCIe Interrupt Status 0 */
>  #define PCIEINTSTS0		0x0084
> @@ -37,33 +40,179 @@
>  #define PCIEDMAINTSTSEN		0x0314
>  #define PCIEDMAINTSTSEN_INIT	GENMASK(15, 0)
>  
> +/* Port Logic Registers 89 */
> +#define PRTLGC89		0x0b70
> +
> +/* Port Logic Registers 90 */
> +#define PRTLGC90		0x0b74
> +
>  /* PCIe Reset Control Register 1 */
>  #define PCIERSTCTRL1		0x0014
>  #define APP_HOLD_PHY_RST	BIT(16)
>  #define APP_LTSSM_ENABLE	BIT(0)
>  
> +/* PCIe Power Management Control */
> +#define PCIEPWRMNGCTRL		0x0070
> +#define APP_CLK_REQ_N		BIT(11)
> +#define APP_CLK_PM_EN		BIT(10)
> +
>  #define RCAR_NUM_SPEED_CHANGE_RETRIES	10
>  #define RCAR_MAX_LINK_SPEED		4
>  
>  #define RCAR_GEN4_PCIE_EP_FUNC_DBI_OFFSET	0x1000
>  #define RCAR_GEN4_PCIE_EP_FUNC_DBI2_OFFSET	0x800
>  
> +#define RCAR_GEN4_PCIE_FIRMEARE_NAME		"rcar_gen4_pcie.bin"
> +#define RCAR_GEN4_PCIE_FIRMEARE_BASE_ADDR	0xc000

s/FIRMEARE/FIRMWARE/

>  struct rcar_gen4_pcie {
>  	struct dw_pcie dw;
>  	void __iomem *base;
> +	/*
> +	 * The R-Car Gen4 documents don't describe the PHY registers' name.
> +	 * But, the initialization procedure describes these offsets. So,
> +	 * this driver has "phy_base + magical offset number" for it.

Make up your own #defines for the offsets.  That would be better than
magic hex offsets below.

> +	void __iomem *phy_base;
>  	struct platform_device *pdev;
>  	enum dw_pcie_device_mode mode;
>  
>  	int (*start_link_enable)(struct rcar_gen4_pcie *rcar);
> +	void (*additional_common_init)(struct rcar_gen4_pcie *rcar);
>  };
>  #define to_rcar_gen4_pcie(_dw)	container_of(_dw, struct rcar_gen4_pcie, dw)
>  
>  struct rcar_gen4_pcie_platdata {
>  	enum dw_pcie_device_mode mode;
>  	int (*start_link_enable)(struct rcar_gen4_pcie *rcar);
> +	void (*additional_common_init)(struct rcar_gen4_pcie *rcar);
>  };
>  
>  /* Common */
> +static void rcar_gen4_pcie_phy_reg_update_bits(struct rcar_gen4_pcie *rcar,
> +					       u32 offset, u32 mask, u32 val)
> +{
> +	u32 tmp;
> +
> +	tmp = readl(rcar->phy_base + offset);
> +	tmp &= ~mask;
> +	tmp |= val;
> +	writel(tmp, rcar->phy_base + offset);
> +}
> +
> +static int rcar_gen4_pcie_reg_check_bit(struct rcar_gen4_pcie *rcar,
> +					u32 offset, u32 mask)
> +{
> +	struct dw_pcie *dw = &rcar->dw;
> +
> +	if (dw_pcie_readl_dbi(dw, offset) & mask)
> +		return -EAGAIN;
> +
> +	return 0;
> +}
> +
> +static int rcar_gen4_pcie_update_phy_firmware(struct rcar_gen4_pcie *rcar)
> +{
> +	const u32 check_addr[] = { 0x00101018, 0x00101118, 0x00101021, 0x00101121};
> +	struct dw_pcie *dw = &rcar->dw;
> +	const struct firmware *fw;
> +	unsigned int i, timeout;
> +	u32 data;
> +	int ret;
> +
> +	ret = request_firmware(&fw, RCAR_GEN4_PCIE_FIRMEARE_NAME, dw->dev);
> +	if (ret)
> +		return ret;

It looks like a failure here leads to a probe failure, so I think this
needs a diagnostic message so the user has a hint about what went
wrong.

> +	for (i = 0; i < (fw->size / 2); i++) {
> +		data = fw->data[i * 2] | fw->data[(i * 2) + 1] << 8;
> +		timeout = 100;
> +retry_data:
> +		dw_pcie_writel_dbi(dw, PRTLGC89, RCAR_GEN4_PCIE_FIRMEARE_BASE_ADDR + i);
> +		dw_pcie_writel_dbi(dw, PRTLGC90, data);
> +		if (rcar_gen4_pcie_reg_check_bit(rcar, PRTLGC89, BIT(30)) < 0) {
> +			if (!(--timeout)) {
> +				ret = -ETIMEDOUT;
> +				goto exit;
> +			}
> +			usleep_range(100, 200);
> +			goto retry_data;
> +		}
> +	}
> +
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(17), BIT(17));
> +
> +	for (i = 0; i < ARRAY_SIZE(check_addr); i++) {
> +		timeout = 100;
> +retry_check:
> +		dw_pcie_writel_dbi(dw, PRTLGC89, check_addr[i]);
> +		ret = rcar_gen4_pcie_reg_check_bit(rcar, PRTLGC89, BIT(30));
> +		ret |= rcar_gen4_pcie_reg_check_bit(rcar, PRTLGC90, BIT(0));
> +		if (ret < 0) {
> +			if (!(--timeout)) {
> +				ret = -ETIMEDOUT;
> +				goto exit;
> +			}
> +			usleep_range(100, 200);
> +			goto retry_check;
> +		}
> +	}
> +
> +	ret = 0;
> +exit:
> +	release_firmware(fw);
> +
> +	return ret;
> +}
> +
> +static int rcar_gen4_pcie_enable_phy(struct rcar_gen4_pcie *rcar)
> +{
> +	struct dw_pcie *dw = &rcar->dw;
> +	u32 val;
> +	int ret;
> +
> +	val = dw_pcie_readl_dbi(dw, PCIE_PORT_FORCE);
> +	val |= PORT_FORCE_DO_DESKEW_FOR_SRIS;
> +	dw_pcie_writel_dbi(dw, PCIE_PORT_FORCE, val);
> +
> +	val = readl(rcar->base + PCIEMSR0);
> +	val |= APP_SRIS_MODE;
> +	writel(val, rcar->base + PCIEMSR0);
> +
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(28), 0);
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(20), 0);
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(12), 0);
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(4), 0);
> +
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(23, 22), BIT(22));
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(18, 16), GENMASK(17, 16));
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(7, 6), BIT(6));
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(2, 0), GENMASK(11, 0));
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x1d4, GENMASK(16, 15), GENMASK(16, 15));
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x514, BIT(26), BIT(26));
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(16), 0);
> +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(19), BIT(19));
> +
> +	val = readl(rcar->base + PCIERSTCTRL1);
> +	val &= ~APP_HOLD_PHY_RST;
> +	writel(val, rcar->base + PCIERSTCTRL1);
> +
> +	ret = readl_poll_timeout(rcar->phy_base + 0x0f8, val, !(val & BIT(18)),
> +				 100, 10000);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = rcar_gen4_pcie_update_phy_firmware(rcar);
> +	if (ret)
> +		return ret;
> +
> +	val = readl(rcar->base + PCIERSTCTRL1);
> +	val |= APP_LTSSM_ENABLE;
> +	writel(val, rcar->base + PCIERSTCTRL1);
> +
> +	return 0;
> +}
> +
>  static void rcar_gen4_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar,
>  					bool enable)
>  {
> @@ -201,6 +350,9 @@ static int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar)
>  	if (ret)
>  		goto err_unprepare;
>  
> +	if (rcar->additional_common_init)
> +		rcar->additional_common_init(rcar);
>
>  	return 0;
>  
>  err_unprepare:
> @@ -242,6 +394,10 @@ static void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar)
>  
>  static int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar)
>  {
> +	rcar->phy_base = devm_platform_ioremap_resource_byname(rcar->pdev, "phy");
> +	if (IS_ERR(rcar->phy_base))
> +		return PTR_ERR(rcar->base);

I don't get it.  This imposes a new requirement (presence of "phy"
resource) on the existing SoCs.  That doesn't sound right.

>  	/* Renesas-specific registers */
>  	rcar->base = devm_platform_ioremap_resource_byname(rcar->pdev, "app");
>  
> @@ -452,6 +608,7 @@ static int rcar_gen4_add_dw_pcie(struct rcar_gen4_pcie *rcar)
>  
>  	rcar->mode = pd->mode;
>  	rcar->start_link_enable = pd->start_link_enable;
> +	rcar->additional_common_init = pd->additional_common_init;
>  
>  	switch (rcar->mode) {
>  	case DW_PCIE_RC_TYPE:
> @@ -521,6 +678,31 @@ static int r8a779f0_pcie_start_link_enable(struct rcar_gen4_pcie *rcar)
>  	return 0;
>  }
>  
> +static int rcar_gen4_pcie_start_link_enable(struct rcar_gen4_pcie *rcar)
> +{
> +	return rcar_gen4_pcie_enable_phy(rcar);
> +}
> +
> +static void rcar_gen4_pcie_additional_common_init(struct rcar_gen4_pcie *rcar)
> +{
> +	struct dw_pcie *dw = &rcar->dw;
> +	u32 val;
> +
> +	/*
> +	 * The SoC manual said the register setting is required. Otherwise,
> +	 * linkup failed.
> +	 */
> +	val = dw_pcie_readl_dbi(dw, PCIE_PORT_LANE_SKEW);
> +	val &= ~PORT_LANE_SKEW_INSERT_MASK;
> +	if (dw->num_lanes < 4)
> +		val |= BIT(6);
> +	dw_pcie_writel_dbi(dw, PCIE_PORT_LANE_SKEW, val);
> +
> +	val = readl(rcar->base + PCIEPWRMNGCTRL);
> +	val |= APP_CLK_REQ_N | APP_CLK_PM_EN;
> +	writel(val, rcar->base + PCIEPWRMNGCTRL);

I don't get this either.  You do this "additional_common_init" part
only for the existing "renesas,rcar-gen4-pcie" and
"renesas,rcar-gen4-pcie-ep", but PCIE_PORT_LANE_SKEW and
PCIEPWRMNGCTRL do not appear in the driver prior to these patches.  I
must be missing something.  Or this is backwards and you meant to do
this for the *new* SoC?

If you need to limit some functionality to existing SoCs and add new
functionality for new SoCs, do those in separate patches if you can.

> +}
> +
>  static struct rcar_gen4_pcie_platdata platdata_r8a779f0_pcie = {
>  	.mode = DW_PCIE_RC_TYPE,
>  	.start_link_enable = r8a779f0_pcie_start_link_enable,
> @@ -533,10 +715,14 @@ static struct rcar_gen4_pcie_platdata platdata_r8a779f0_pcie_ep = {
>  
>  static struct rcar_gen4_pcie_platdata platdata_rcar_gen4_pcie = {
>  	.mode = DW_PCIE_RC_TYPE,
> +	.start_link_enable = rcar_gen4_pcie_start_link_enable,
> +	.additional_common_init = rcar_gen4_pcie_additional_common_init,
>  };
>  
>  static struct rcar_gen4_pcie_platdata platdata_rcar_gen4_pcie_ep = {
>  	.mode = DW_PCIE_EP_TYPE,
> +	.start_link_enable = rcar_gen4_pcie_start_link_enable,
> +	.additional_common_init = rcar_gen4_pcie_additional_common_init,
>  };
>  
>  static const struct of_device_id rcar_gen4_pcie_of_match[] = {
> -- 
> 2.25.1
>
Yoshihiro Shimoda March 27, 2024, 5:32 a.m. UTC | #2
Hi Bjorn,

> From: Bjorn Helgaas, Sent: Wednesday, March 27, 2024 5:49 AM
> 
> The subject line should specify which controller(s) this adds support
> for.

I got it. I'll change the subject.

> On Tue, Mar 26, 2024 at 11:45:39AM +0900, Yoshihiro Shimoda wrote:
> > The PCIe controllers of R-Car V4H (r8a779g0) and one more SoC require
> > different initializing settings than R-Car S4-8 (r8a779f0). So, add
> > specific functions for them as "renesas,rcar-gen4-pcie{-ep}" compatible.
> 
> I can't tell from this what's being added.  This should say something
> like "this driver previously supported r8....  Add support for r8...."
> so it's clear what was existing and what is new.

I got it. I'll modify the description.

> Hmm... the first use of request_firmware() in drivers/pci/.  That
> warrants a mention here as it's a pretty significant change.

I got it. I'll add such a description.

> > Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> > ---
> >  drivers/pci/controller/dwc/pcie-rcar-gen4.c | 188 +++++++++++++++++++-
> >  1 file changed, 187 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> > index a37613dd9ff4..7f3b5e9ca405 100644
> > --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> > +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> > @@ -5,8 +5,10 @@
> >   */
> >
> >  #include <linux/delay.h>
> > +#include <linux/firmware.h>
> >  #include <linux/interrupt.h>
> >  #include <linux/io.h>
> > +#include <linux/iopoll.h>
> >  #include <linux/module.h>
> >  #include <linux/of.h>
> >  #include <linux/pci.h>
> > @@ -20,9 +22,10 @@
> >  /* Renesas-specific */
> >  /* PCIe Mode Setting Register 0 */
> >  #define PCIEMSR0		0x0000
> > -#define BIFUR_MOD_SET_ON	BIT(0)
> > +#define APP_SRIS_MODE		BIT(6)
> >  #define DEVICE_TYPE_EP		0
> >  #define DEVICE_TYPE_RC		BIT(4)
> > +#define BIFUR_MOD_SET_ON	BIT(0)
> >
> >  /* PCIe Interrupt Status 0 */
> >  #define PCIEINTSTS0		0x0084
> > @@ -37,33 +40,179 @@
> >  #define PCIEDMAINTSTSEN		0x0314
> >  #define PCIEDMAINTSTSEN_INIT	GENMASK(15, 0)
> >
> > +/* Port Logic Registers 89 */
> > +#define PRTLGC89		0x0b70
> > +
> > +/* Port Logic Registers 90 */
> > +#define PRTLGC90		0x0b74
> > +
> >  /* PCIe Reset Control Register 1 */
> >  #define PCIERSTCTRL1		0x0014
> >  #define APP_HOLD_PHY_RST	BIT(16)
> >  #define APP_LTSSM_ENABLE	BIT(0)
> >
> > +/* PCIe Power Management Control */
> > +#define PCIEPWRMNGCTRL		0x0070
> > +#define APP_CLK_REQ_N		BIT(11)
> > +#define APP_CLK_PM_EN		BIT(10)
> > +
> >  #define RCAR_NUM_SPEED_CHANGE_RETRIES	10
> >  #define RCAR_MAX_LINK_SPEED		4
> >
> >  #define RCAR_GEN4_PCIE_EP_FUNC_DBI_OFFSET	0x1000
> >  #define RCAR_GEN4_PCIE_EP_FUNC_DBI2_OFFSET	0x800
> >
> > +#define RCAR_GEN4_PCIE_FIRMEARE_NAME		"rcar_gen4_pcie.bin"
> > +#define RCAR_GEN4_PCIE_FIRMEARE_BASE_ADDR	0xc000
> 
> s/FIRMEARE/FIRMWARE/

Oops. I'll fix it.

> >  struct rcar_gen4_pcie {
> >  	struct dw_pcie dw;
> >  	void __iomem *base;
> > +	/*
> > +	 * The R-Car Gen4 documents don't describe the PHY registers' name.
> > +	 * But, the initialization procedure describes these offsets. So,
> > +	 * this driver has "phy_base + magical offset number" for it.
> 
> Make up your own #defines for the offsets.  That would be better than
> magic hex offsets below.

I got it. I'll add #defines for it.

> > +	void __iomem *phy_base;
> >  	struct platform_device *pdev;
> >  	enum dw_pcie_device_mode mode;
> >
> >  	int (*start_link_enable)(struct rcar_gen4_pcie *rcar);
> > +	void (*additional_common_init)(struct rcar_gen4_pcie *rcar);
> >  };
> >  #define to_rcar_gen4_pcie(_dw)	container_of(_dw, struct rcar_gen4_pcie, dw)
> >
> >  struct rcar_gen4_pcie_platdata {
> >  	enum dw_pcie_device_mode mode;
> >  	int (*start_link_enable)(struct rcar_gen4_pcie *rcar);
> > +	void (*additional_common_init)(struct rcar_gen4_pcie *rcar);
> >  };
> >
> >  /* Common */
> > +static void rcar_gen4_pcie_phy_reg_update_bits(struct rcar_gen4_pcie *rcar,
> > +					       u32 offset, u32 mask, u32 val)
> > +{
> > +	u32 tmp;
> > +
> > +	tmp = readl(rcar->phy_base + offset);
> > +	tmp &= ~mask;
> > +	tmp |= val;
> > +	writel(tmp, rcar->phy_base + offset);
> > +}
> > +
> > +static int rcar_gen4_pcie_reg_check_bit(struct rcar_gen4_pcie *rcar,
> > +					u32 offset, u32 mask)
> > +{
> > +	struct dw_pcie *dw = &rcar->dw;
> > +
> > +	if (dw_pcie_readl_dbi(dw, offset) & mask)
> > +		return -EAGAIN;
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_gen4_pcie_update_phy_firmware(struct rcar_gen4_pcie *rcar)
> > +{
> > +	const u32 check_addr[] = { 0x00101018, 0x00101118, 0x00101021, 0x00101121};
> > +	struct dw_pcie *dw = &rcar->dw;
> > +	const struct firmware *fw;
> > +	unsigned int i, timeout;
> > +	u32 data;
> > +	int ret;
> > +
> > +	ret = request_firmware(&fw, RCAR_GEN4_PCIE_FIRMEARE_NAME, dw->dev);
> > +	if (ret)
> > +		return ret;
> 
> It looks like a failure here leads to a probe failure, so I think this
> needs a diagnostic message so the user has a hint about what went
> wrong.

I got it. I'll add such a code here.

> > +	for (i = 0; i < (fw->size / 2); i++) {
> > +		data = fw->data[i * 2] | fw->data[(i * 2) + 1] << 8;
> > +		timeout = 100;
> > +retry_data:
> > +		dw_pcie_writel_dbi(dw, PRTLGC89, RCAR_GEN4_PCIE_FIRMEARE_BASE_ADDR + i);
> > +		dw_pcie_writel_dbi(dw, PRTLGC90, data);
> > +		if (rcar_gen4_pcie_reg_check_bit(rcar, PRTLGC89, BIT(30)) < 0) {
> > +			if (!(--timeout)) {
> > +				ret = -ETIMEDOUT;
> > +				goto exit;
> > +			}
> > +			usleep_range(100, 200);
> > +			goto retry_data;
> > +		}
> > +	}
> > +
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(17), BIT(17));
> > +
> > +	for (i = 0; i < ARRAY_SIZE(check_addr); i++) {
> > +		timeout = 100;
> > +retry_check:
> > +		dw_pcie_writel_dbi(dw, PRTLGC89, check_addr[i]);
> > +		ret = rcar_gen4_pcie_reg_check_bit(rcar, PRTLGC89, BIT(30));
> > +		ret |= rcar_gen4_pcie_reg_check_bit(rcar, PRTLGC90, BIT(0));
> > +		if (ret < 0) {
> > +			if (!(--timeout)) {
> > +				ret = -ETIMEDOUT;
> > +				goto exit;
> > +			}
> > +			usleep_range(100, 200);
> > +			goto retry_check;
> > +		}
> > +	}
> > +
> > +	ret = 0;
> > +exit:
> > +	release_firmware(fw);
> > +
> > +	return ret;
> > +}
> > +
> > +static int rcar_gen4_pcie_enable_phy(struct rcar_gen4_pcie *rcar)
> > +{
> > +	struct dw_pcie *dw = &rcar->dw;
> > +	u32 val;
> > +	int ret;
> > +
> > +	val = dw_pcie_readl_dbi(dw, PCIE_PORT_FORCE);
> > +	val |= PORT_FORCE_DO_DESKEW_FOR_SRIS;
> > +	dw_pcie_writel_dbi(dw, PCIE_PORT_FORCE, val);
> > +
> > +	val = readl(rcar->base + PCIEMSR0);
> > +	val |= APP_SRIS_MODE;
> > +	writel(val, rcar->base + PCIEMSR0);
> > +
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(28), 0);
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(20), 0);
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(12), 0);
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(4), 0);
> > +
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(23, 22), BIT(22));
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(18, 16), GENMASK(17, 16));
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(7, 6), BIT(6));
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(2, 0), GENMASK(11, 0));
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x1d4, GENMASK(16, 15), GENMASK(16, 15));
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x514, BIT(26), BIT(26));
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(16), 0);
> > +	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(19), BIT(19));
> > +
> > +	val = readl(rcar->base + PCIERSTCTRL1);
> > +	val &= ~APP_HOLD_PHY_RST;
> > +	writel(val, rcar->base + PCIERSTCTRL1);
> > +
> > +	ret = readl_poll_timeout(rcar->phy_base + 0x0f8, val, !(val & BIT(18)),
> > +				 100, 10000);
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	ret = rcar_gen4_pcie_update_phy_firmware(rcar);
> > +	if (ret)
> > +		return ret;
> > +
> > +	val = readl(rcar->base + PCIERSTCTRL1);
> > +	val |= APP_LTSSM_ENABLE;
> > +	writel(val, rcar->base + PCIERSTCTRL1);
> > +
> > +	return 0;
> > +}
> > +
> >  static void rcar_gen4_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar,
> >  					bool enable)
> >  {
> > @@ -201,6 +350,9 @@ static int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar)
> >  	if (ret)
> >  		goto err_unprepare;
> >
> > +	if (rcar->additional_common_init)
> > +		rcar->additional_common_init(rcar);
> >
> >  	return 0;
> >
> >  err_unprepare:
> > @@ -242,6 +394,10 @@ static void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar)
> >
> >  static int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar)
> >  {
> > +	rcar->phy_base = devm_platform_ioremap_resource_byname(rcar->pdev, "phy");
> > +	if (IS_ERR(rcar->phy_base))
> > +		return PTR_ERR(rcar->base);
> 
> I don't get it.  This imposes a new requirement (presence of "phy"
> resource) on the existing SoCs.  That doesn't sound right.

According to the dt-binding doc, the existing SoCs are also required for the "phy".
That's why I didn't add any condition to simplify the code.

> >  	/* Renesas-specific registers */
> >  	rcar->base = devm_platform_ioremap_resource_byname(rcar->pdev, "app");
> >
> > @@ -452,6 +608,7 @@ static int rcar_gen4_add_dw_pcie(struct rcar_gen4_pcie *rcar)
> >
> >  	rcar->mode = pd->mode;
> >  	rcar->start_link_enable = pd->start_link_enable;
> > +	rcar->additional_common_init = pd->additional_common_init;
> >
> >  	switch (rcar->mode) {
> >  	case DW_PCIE_RC_TYPE:
> > @@ -521,6 +678,31 @@ static int r8a779f0_pcie_start_link_enable(struct rcar_gen4_pcie *rcar)
> >  	return 0;
> >  }
> >
> > +static int rcar_gen4_pcie_start_link_enable(struct rcar_gen4_pcie *rcar)
> > +{
> > +	return rcar_gen4_pcie_enable_phy(rcar);
> > +}
> > +
> > +static void rcar_gen4_pcie_additional_common_init(struct rcar_gen4_pcie *rcar)
> > +{
> > +	struct dw_pcie *dw = &rcar->dw;
> > +	u32 val;
> > +
> > +	/*
> > +	 * The SoC manual said the register setting is required. Otherwise,
> > +	 * linkup failed.
> > +	 */
> > +	val = dw_pcie_readl_dbi(dw, PCIE_PORT_LANE_SKEW);
> > +	val &= ~PORT_LANE_SKEW_INSERT_MASK;
> > +	if (dw->num_lanes < 4)
> > +		val |= BIT(6);
> > +	dw_pcie_writel_dbi(dw, PCIE_PORT_LANE_SKEW, val);
> > +
> > +	val = readl(rcar->base + PCIEPWRMNGCTRL);
> > +	val |= APP_CLK_REQ_N | APP_CLK_PM_EN;
> > +	writel(val, rcar->base + PCIEPWRMNGCTRL);
> 
> I don't get this either.  You do this "additional_common_init" part
> only for the existing "renesas,rcar-gen4-pcie" and
> "renesas,rcar-gen4-pcie-ep", but PCIE_PORT_LANE_SKEW and
> PCIEPWRMNGCTRL do not appear in the driver prior to these patches.  I
> must be missing something.  Or this is backwards and you meant to do
> this for the *new* SoC?

I'm sorry for the confusion. This is for the new SoC.

I should have explained before though, existing support SoC is:
- r8a779f0 as "renesas,rcar-gen4-pcie" and "renesas,rcar-gen4-pcie-ep".

After we applied the patch series:

- r8a779f0 as "renesas,r8a779f0-pcie" and "renesas,r8a779f0-pcie-ep".
- r8a779g0 as "renesas,rcar-gen4-pcie" and "renesas,rcar-gen4--pcie-ep".

Also, I have a plan to add r8a779h0 support in the future:

- r8a779f0 as "renesas,r8a779f0-pcie" and "renesas,r8a779f0-pcie-ep".
- r8a779g0 as "renesas,rcar-gen4-pcie" and "renesas,rcar-gen4--pcie-ep".
- r8a779h0 as "renesas,rcar-gen4-pcie" and "renesas,rcar-gen4--pcie-ep".

And r8a779[gh]0 need this additional_common_init.

> If you need to limit some functionality to existing SoCs and add new
> functionality for new SoCs, do those in separate patches if you can.

I got it. I'll make such a patch if I can.

Best regards,
Yoshihiro Shimoda

> > +}
> > +
> >  static struct rcar_gen4_pcie_platdata platdata_r8a779f0_pcie = {
> >  	.mode = DW_PCIE_RC_TYPE,
> >  	.start_link_enable = r8a779f0_pcie_start_link_enable,
> > @@ -533,10 +715,14 @@ static struct rcar_gen4_pcie_platdata platdata_r8a779f0_pcie_ep = {
> >
> >  static struct rcar_gen4_pcie_platdata platdata_rcar_gen4_pcie = {
> >  	.mode = DW_PCIE_RC_TYPE,
> > +	.start_link_enable = rcar_gen4_pcie_start_link_enable,
> > +	.additional_common_init = rcar_gen4_pcie_additional_common_init,
> >  };
> >
> >  static struct rcar_gen4_pcie_platdata platdata_rcar_gen4_pcie_ep = {
> >  	.mode = DW_PCIE_EP_TYPE,
> > +	.start_link_enable = rcar_gen4_pcie_start_link_enable,
> > +	.additional_common_init = rcar_gen4_pcie_additional_common_init,
> >  };
> >
> >  static const struct of_device_id rcar_gen4_pcie_of_match[] = {
> > --
> > 2.25.1
> >
Bjorn Helgaas March 27, 2024, 6:14 p.m. UTC | #3
On Wed, Mar 27, 2024 at 05:32:57AM +0000, Yoshihiro Shimoda wrote:
> > From: Bjorn Helgaas, Sent: Wednesday, March 27, 2024 5:49 AM

> > >  static int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar)
> > >  {
> > > +	rcar->phy_base = devm_platform_ioremap_resource_byname(rcar->pdev, "phy");
> > > +	if (IS_ERR(rcar->phy_base))
> > > +		return PTR_ERR(rcar->base);
> > 
> > I don't get it.  This imposes a new requirement (presence of "phy"
> > resource) on the existing SoCs.  That doesn't sound right.
> 
> According to the dt-binding doc, the existing SoCs are also required
> for the "phy".  That's why I didn't add any condition to simplify
> the code.

Is there anything that enforces that?  Is it possible that DTs exist
in the field without it?  We don't want to break any existing setup.
Yoshihiro Shimoda March 29, 2024, 2:24 a.m. UTC | #4
Hi Bjorn,

> From: Bjorn Helgaas, Sent: Thursday, March 28, 2024 3:15 AM
> 
> On Wed, Mar 27, 2024 at 05:32:57AM +0000, Yoshihiro Shimoda wrote:
> > > From: Bjorn Helgaas, Sent: Wednesday, March 27, 2024 5:49 AM
> 
> > > >  static int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar)
> > > >  {
> > > > +	rcar->phy_base = devm_platform_ioremap_resource_byname(rcar->pdev, "phy");
> > > > +	if (IS_ERR(rcar->phy_base))
> > > > +		return PTR_ERR(rcar->base);
> > >
> > > I don't get it.  This imposes a new requirement (presence of "phy"
> > > resource) on the existing SoCs.  That doesn't sound right.
> >
> > According to the dt-binding doc, the existing SoCs are also required
> > for the "phy".  That's why I didn't add any condition to simplify
> > the code.
> 
> Is there anything that enforces that?  Is it possible that DTs exist
> in the field without it?  We don't want to break any existing setup.

Using make dtbs_check can detect an error if the "phy" doesn't exist like below:

/home/shimoda/development/linux/linux/arch/arm64/boot/dts/renesas/r8a779f0-spider.dtb: pcie@e65d0000: reg-names:5: 'phy' was expected
        from schema $id: http://devicetree.org/schemas/pci/rcar-gen4-pci-host.yaml#

So, I believe that this can enforce that in review process at least.
Now arch/arm64/boot/dts/renesas/r8a779f0.dtsi has the pcie compatible,
and all pcie nodes in the dtsi have "phy". So, this patch will not break any existing setup.

Best regards,
Yoshihiro Shimoda
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index a37613dd9ff4..7f3b5e9ca405 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -5,8 +5,10 @@ 
  */
 
 #include <linux/delay.h>
+#include <linux/firmware.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/pci.h>
@@ -20,9 +22,10 @@ 
 /* Renesas-specific */
 /* PCIe Mode Setting Register 0 */
 #define PCIEMSR0		0x0000
-#define BIFUR_MOD_SET_ON	BIT(0)
+#define APP_SRIS_MODE		BIT(6)
 #define DEVICE_TYPE_EP		0
 #define DEVICE_TYPE_RC		BIT(4)
+#define BIFUR_MOD_SET_ON	BIT(0)
 
 /* PCIe Interrupt Status 0 */
 #define PCIEINTSTS0		0x0084
@@ -37,33 +40,179 @@ 
 #define PCIEDMAINTSTSEN		0x0314
 #define PCIEDMAINTSTSEN_INIT	GENMASK(15, 0)
 
+/* Port Logic Registers 89 */
+#define PRTLGC89		0x0b70
+
+/* Port Logic Registers 90 */
+#define PRTLGC90		0x0b74
+
 /* PCIe Reset Control Register 1 */
 #define PCIERSTCTRL1		0x0014
 #define APP_HOLD_PHY_RST	BIT(16)
 #define APP_LTSSM_ENABLE	BIT(0)
 
+/* PCIe Power Management Control */
+#define PCIEPWRMNGCTRL		0x0070
+#define APP_CLK_REQ_N		BIT(11)
+#define APP_CLK_PM_EN		BIT(10)
+
 #define RCAR_NUM_SPEED_CHANGE_RETRIES	10
 #define RCAR_MAX_LINK_SPEED		4
 
 #define RCAR_GEN4_PCIE_EP_FUNC_DBI_OFFSET	0x1000
 #define RCAR_GEN4_PCIE_EP_FUNC_DBI2_OFFSET	0x800
 
+#define RCAR_GEN4_PCIE_FIRMEARE_NAME		"rcar_gen4_pcie.bin"
+#define RCAR_GEN4_PCIE_FIRMEARE_BASE_ADDR	0xc000
+
 struct rcar_gen4_pcie {
 	struct dw_pcie dw;
 	void __iomem *base;
+	/*
+	 * The R-Car Gen4 documents don't describe the PHY registers' name.
+	 * But, the initialization procedure describes these offsets. So,
+	 * this driver has "phy_base + magical offset number" for it.
+	 */
+	void __iomem *phy_base;
 	struct platform_device *pdev;
 	enum dw_pcie_device_mode mode;
 
 	int (*start_link_enable)(struct rcar_gen4_pcie *rcar);
+	void (*additional_common_init)(struct rcar_gen4_pcie *rcar);
 };
 #define to_rcar_gen4_pcie(_dw)	container_of(_dw, struct rcar_gen4_pcie, dw)
 
 struct rcar_gen4_pcie_platdata {
 	enum dw_pcie_device_mode mode;
 	int (*start_link_enable)(struct rcar_gen4_pcie *rcar);
+	void (*additional_common_init)(struct rcar_gen4_pcie *rcar);
 };
 
 /* Common */
+static void rcar_gen4_pcie_phy_reg_update_bits(struct rcar_gen4_pcie *rcar,
+					       u32 offset, u32 mask, u32 val)
+{
+	u32 tmp;
+
+	tmp = readl(rcar->phy_base + offset);
+	tmp &= ~mask;
+	tmp |= val;
+	writel(tmp, rcar->phy_base + offset);
+}
+
+static int rcar_gen4_pcie_reg_check_bit(struct rcar_gen4_pcie *rcar,
+					u32 offset, u32 mask)
+{
+	struct dw_pcie *dw = &rcar->dw;
+
+	if (dw_pcie_readl_dbi(dw, offset) & mask)
+		return -EAGAIN;
+
+	return 0;
+}
+
+static int rcar_gen4_pcie_update_phy_firmware(struct rcar_gen4_pcie *rcar)
+{
+	const u32 check_addr[] = { 0x00101018, 0x00101118, 0x00101021, 0x00101121};
+	struct dw_pcie *dw = &rcar->dw;
+	const struct firmware *fw;
+	unsigned int i, timeout;
+	u32 data;
+	int ret;
+
+	ret = request_firmware(&fw, RCAR_GEN4_PCIE_FIRMEARE_NAME, dw->dev);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < (fw->size / 2); i++) {
+		data = fw->data[i * 2] | fw->data[(i * 2) + 1] << 8;
+		timeout = 100;
+retry_data:
+		dw_pcie_writel_dbi(dw, PRTLGC89, RCAR_GEN4_PCIE_FIRMEARE_BASE_ADDR + i);
+		dw_pcie_writel_dbi(dw, PRTLGC90, data);
+		if (rcar_gen4_pcie_reg_check_bit(rcar, PRTLGC89, BIT(30)) < 0) {
+			if (!(--timeout)) {
+				ret = -ETIMEDOUT;
+				goto exit;
+			}
+			usleep_range(100, 200);
+			goto retry_data;
+		}
+	}
+
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(17), BIT(17));
+
+	for (i = 0; i < ARRAY_SIZE(check_addr); i++) {
+		timeout = 100;
+retry_check:
+		dw_pcie_writel_dbi(dw, PRTLGC89, check_addr[i]);
+		ret = rcar_gen4_pcie_reg_check_bit(rcar, PRTLGC89, BIT(30));
+		ret |= rcar_gen4_pcie_reg_check_bit(rcar, PRTLGC90, BIT(0));
+		if (ret < 0) {
+			if (!(--timeout)) {
+				ret = -ETIMEDOUT;
+				goto exit;
+			}
+			usleep_range(100, 200);
+			goto retry_check;
+		}
+	}
+
+	ret = 0;
+exit:
+	release_firmware(fw);
+
+	return ret;
+}
+
+static int rcar_gen4_pcie_enable_phy(struct rcar_gen4_pcie *rcar)
+{
+	struct dw_pcie *dw = &rcar->dw;
+	u32 val;
+	int ret;
+
+	val = dw_pcie_readl_dbi(dw, PCIE_PORT_FORCE);
+	val |= PORT_FORCE_DO_DESKEW_FOR_SRIS;
+	dw_pcie_writel_dbi(dw, PCIE_PORT_FORCE, val);
+
+	val = readl(rcar->base + PCIEMSR0);
+	val |= APP_SRIS_MODE;
+	writel(val, rcar->base + PCIEMSR0);
+
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(28), 0);
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(20), 0);
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(12), 0);
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x700, BIT(4), 0);
+
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(23, 22), BIT(22));
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(18, 16), GENMASK(17, 16));
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(7, 6), BIT(6));
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x148, GENMASK(2, 0), GENMASK(11, 0));
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x1d4, GENMASK(16, 15), GENMASK(16, 15));
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x514, BIT(26), BIT(26));
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(16), 0);
+	rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(19), BIT(19));
+
+	val = readl(rcar->base + PCIERSTCTRL1);
+	val &= ~APP_HOLD_PHY_RST;
+	writel(val, rcar->base + PCIERSTCTRL1);
+
+	ret = readl_poll_timeout(rcar->phy_base + 0x0f8, val, !(val & BIT(18)),
+				 100, 10000);
+	if (ret < 0)
+		return ret;
+
+	ret = rcar_gen4_pcie_update_phy_firmware(rcar);
+	if (ret)
+		return ret;
+
+	val = readl(rcar->base + PCIERSTCTRL1);
+	val |= APP_LTSSM_ENABLE;
+	writel(val, rcar->base + PCIERSTCTRL1);
+
+	return 0;
+}
+
 static void rcar_gen4_pcie_ltssm_enable(struct rcar_gen4_pcie *rcar,
 					bool enable)
 {
@@ -201,6 +350,9 @@  static int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar)
 	if (ret)
 		goto err_unprepare;
 
+	if (rcar->additional_common_init)
+		rcar->additional_common_init(rcar);
+
 	return 0;
 
 err_unprepare:
@@ -242,6 +394,10 @@  static void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar)
 
 static int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar)
 {
+	rcar->phy_base = devm_platform_ioremap_resource_byname(rcar->pdev, "phy");
+	if (IS_ERR(rcar->phy_base))
+		return PTR_ERR(rcar->base);
+
 	/* Renesas-specific registers */
 	rcar->base = devm_platform_ioremap_resource_byname(rcar->pdev, "app");
 
@@ -452,6 +608,7 @@  static int rcar_gen4_add_dw_pcie(struct rcar_gen4_pcie *rcar)
 
 	rcar->mode = pd->mode;
 	rcar->start_link_enable = pd->start_link_enable;
+	rcar->additional_common_init = pd->additional_common_init;
 
 	switch (rcar->mode) {
 	case DW_PCIE_RC_TYPE:
@@ -521,6 +678,31 @@  static int r8a779f0_pcie_start_link_enable(struct rcar_gen4_pcie *rcar)
 	return 0;
 }
 
+static int rcar_gen4_pcie_start_link_enable(struct rcar_gen4_pcie *rcar)
+{
+	return rcar_gen4_pcie_enable_phy(rcar);
+}
+
+static void rcar_gen4_pcie_additional_common_init(struct rcar_gen4_pcie *rcar)
+{
+	struct dw_pcie *dw = &rcar->dw;
+	u32 val;
+
+	/*
+	 * The SoC manual said the register setting is required. Otherwise,
+	 * linkup failed.
+	 */
+	val = dw_pcie_readl_dbi(dw, PCIE_PORT_LANE_SKEW);
+	val &= ~PORT_LANE_SKEW_INSERT_MASK;
+	if (dw->num_lanes < 4)
+		val |= BIT(6);
+	dw_pcie_writel_dbi(dw, PCIE_PORT_LANE_SKEW, val);
+
+	val = readl(rcar->base + PCIEPWRMNGCTRL);
+	val |= APP_CLK_REQ_N | APP_CLK_PM_EN;
+	writel(val, rcar->base + PCIEPWRMNGCTRL);
+}
+
 static struct rcar_gen4_pcie_platdata platdata_r8a779f0_pcie = {
 	.mode = DW_PCIE_RC_TYPE,
 	.start_link_enable = r8a779f0_pcie_start_link_enable,
@@ -533,10 +715,14 @@  static struct rcar_gen4_pcie_platdata platdata_r8a779f0_pcie_ep = {
 
 static struct rcar_gen4_pcie_platdata platdata_rcar_gen4_pcie = {
 	.mode = DW_PCIE_RC_TYPE,
+	.start_link_enable = rcar_gen4_pcie_start_link_enable,
+	.additional_common_init = rcar_gen4_pcie_additional_common_init,
 };
 
 static struct rcar_gen4_pcie_platdata platdata_rcar_gen4_pcie_ep = {
 	.mode = DW_PCIE_EP_TYPE,
+	.start_link_enable = rcar_gen4_pcie_start_link_enable,
+	.additional_common_init = rcar_gen4_pcie_additional_common_init,
 };
 
 static const struct of_device_id rcar_gen4_pcie_of_match[] = {