RE: [PATCHv3 2/3] ARMv8: layerscape: add the pcie ep function support

[M.h. Lian]

> -----Original Message-----
> From: Bao Xiaowei [mailto:xiaowei.bao@xxxxxxx]
> Sent: Friday, November 10, 2017 10:49 AM
> To: robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; catalin.marinas@xxxxxxx;
> will.deacon@xxxxxxx; bhelgaas@xxxxxxxxxx; shawnguo@xxxxxxxxxx;
> Madalin-cristian Bucur <madalin.bucur@xxxxxxx>; Sumit Garg
> <sumit.garg@xxxxxxx>; Y.b. Lu <yangbo.lu@xxxxxxx>; hongtao.jia@xxxxxxx;
> Andy Tang <andy.tang@xxxxxxx>; Leo Li <leoyang.li@xxxxxxx>;
> kishon@xxxxxx; jingoohan1@xxxxxxxxx; pbrobinson@xxxxxxxxx;
> songxiaowei@xxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-arm-
> kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-
> pci@xxxxxxxxxxxxxxx; linuxppc-dev@xxxxxxxxxxxxxxxx; Z.q. Hou
> <zhiqiang.hou@xxxxxxx>; Mingkai Hu <mingkai.hu@xxxxxxx>; M.h. Lian
> <minghuan.lian@xxxxxxx>
> Cc: Xiaowei Bao <xiaowei.bao@xxxxxxx>
> Subject: [PATCHv3 2/3] ARMv8: layerscape: add the pcie ep function support
> 
> Add the pcie controller ep function support of layerscape base on pcie ep
> framework.
> 
> Signed-off-by: Bao Xiaowei <xiaowei.bao@xxxxxxx>
> ---
>   v2:
>   - fix the ioremap function used but no ioumap issue
>   - optimize the code structure
>   - add code comments
>   v3:
>   - fix the msi outband window request failed issue
> 
>  drivers/pci/dwc/pci-layerscape.c | 124
> +++++++++++++++++++++++++++++++++++++--
>  1 file changed, 118 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/pci/dwc/pci-layerscape.c b/drivers/pci/dwc/pci-layerscape.c
> index 87fa486bee2c..d787375528eb 100644
> --- a/drivers/pci/dwc/pci-layerscape.c
> +++ b/drivers/pci/dwc/pci-layerscape.c
> @@ -34,7 +34,12 @@
>  /* PEX Internal Configuration Registers */
>  #define PCIE_STRFMR1		0x71c /* Symbol Timer & Filter Mask Register1
> */
> 
> +#define PCIE_DBI2_BASE		0x1000	/* DBI2 base address*/
> +#define PCIE_MSI_MSG_DATA_OFF	0x5c	/* MSI Data register address*/
> +#define PCIE_MSI_OB_SIZE	4096
> +#define PCIE_MSI_ADDR_OFFSET	(1024 * 1024)
>  #define PCIE_IATU_NUM		6
> +#define PCIE_EP_ADDR_SPACE_SIZE 0x100000000
> 
>  struct ls_pcie_drvdata {
>  	u32 lut_offset;
> @@ -44,12 +49,20 @@ struct ls_pcie_drvdata {
>  	const struct dw_pcie_ops *dw_pcie_ops;  };
> 
> +struct ls_pcie_ep {
> +	dma_addr_t msi_phys_addr;
> +	void __iomem *msi_virt_addr;
> +	u64 msi_msg_addr;
> +	u16 msi_msg_data;
> +};
> +
>  struct ls_pcie {
>  	struct dw_pcie *pci;
>  	void __iomem *lut;
>  	struct regmap *scfg;
>  	const struct ls_pcie_drvdata *drvdata;
>  	int index;
> +	struct ls_pcie_ep *pcie_ep;
>  };
> 
>  #define to_ls_pcie(x)	dev_get_drvdata((x)->dev)
> @@ -263,6 +276,100 @@ static const struct of_device_id ls_pcie_of_match[] =
> {
>  	{ },
>  };
> 
> +static void ls_pcie_raise_msi_irq(struct ls_pcie_ep *pcie_ep) {
> +	iowrite32(pcie_ep->msi_msg_data, pcie_ep->msi_virt_addr); }
> +
> +static int ls_pcie_raise_irq(struct dw_pcie_ep *ep,
> +		enum pci_epc_irq_type type, u8 interrupt_num) {
> +	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> +	struct ls_pcie *pcie = to_ls_pcie(pci);
> +	struct ls_pcie_ep *pcie_ep = pcie->pcie_ep;
> +	u32 free_win;
> +
> +	/* get the msi message address and msi message data */
> +	pcie_ep->msi_msg_addr = ioread32(pci->dbi_base +
> MSI_MESSAGE_ADDR_L32) |
> +		(((u64)ioread32(pci->dbi_base + MSI_MESSAGE_ADDR_U32)) <<
> 32);
> +	pcie_ep->msi_msg_data = ioread16(pci->dbi_base +
> +PCIE_MSI_MSG_DATA_OFF);
> +
> +	/* request and config the outband window for msi */
> +	free_win = find_first_zero_bit(&ep->ob_window_map,
> +					sizeof(ep->ob_window_map));
> +	if (free_win >= ep->num_ob_windows) {
> +		dev_err(pci->dev, "no free outbound window\n");
> +		return -ENOMEM;
> +	}
> +
> +	dw_pcie_prog_outbound_atu(pci, free_win, PCIE_ATU_TYPE_MEM,
> +					pcie_ep->msi_phys_addr,
> +					pcie_ep->msi_msg_addr,
> +					PCIE_MSI_OB_SIZE);
> +
> +	set_bit(free_win, &ep->ob_window_map);
> +
> +	/* generate the msi interrupt */
> +	ls_pcie_raise_msi_irq(pcie_ep);
> +
> +	/* release the outband window of msi */
> +	dw_pcie_disable_atu(pci, free_win, DW_PCIE_REGION_OUTBOUND);
> +	clear_bit(free_win, &ep->ob_window_map);
> +
> +	return 0;
> +}
> +
> +static struct dw_pcie_ep_ops pcie_ep_ops = {
> +	.raise_irq = ls_pcie_raise_irq,
> +};
> +
> +static int __init ls_add_pcie_ep(struct ls_pcie *pcie,
> +					struct platform_device *pdev)
> +{
> +	struct dw_pcie *pci = pcie->pci;
> +	struct device *dev = pci->dev;
> +	struct dw_pcie_ep *ep;
> +	struct ls_pcie_ep *pcie_ep;
> +	struct resource *cfg_res;
> +	int ret;
> +
> +	ep = &pci->ep;
> +	ep->ops = &pcie_ep_ops;
> +
> +	pcie_ep = devm_kzalloc(dev, sizeof(*pcie_ep), GFP_KERNEL);
> +	if (!pcie_ep)
> +		return -ENOMEM;
> +
> +	pcie->pcie_ep = pcie_ep;
> +
> +	cfg_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> "config");
> +	if (cfg_res) {
> +		ep->phys_base = cfg_res->start;
> +		ep->addr_size = PCIE_EP_ADDR_SPACE_SIZE;
> +	} else {
> +		dev_err(dev, "missing *config* space\n");
> +		return -ENODEV;
> +	}
> +
> +	pcie_ep->msi_phys_addr = ep->phys_base + PCIE_MSI_ADDR_OFFSET;
> +
> +	pcie_ep->msi_virt_addr = ioremap(pcie_ep->msi_phys_addr,
> +						PCIE_MSI_OB_SIZE);
> +	if (!pcie_ep->msi_virt_addr) {
> +		dev_err(dev, "failed to map MSI outbound region\n");
> +		return -ENOMEM;
> +	}
> +
> +	ret = dw_pcie_ep_init(ep);
> +	if (ret) {
> +		dev_err(dev, "failed to initialize endpoint\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +
[Minghuan Lian] Remove unnecessary blank line.
> +}
> +
>  static int __init ls_add_pcie_port(struct ls_pcie *pcie)  {
>  	struct dw_pcie *pci = pcie->pci;
> @@ -309,16 +416,21 @@ static int __init ls_pcie_probe(struct platform_device
> *pdev)
>  	if (IS_ERR(pci->dbi_base))
>  		return PTR_ERR(pci->dbi_base);
> 
> -	pcie->lut = pci->dbi_base + pcie->drvdata->lut_offset;
> +	pci->dbi_base2 = pci->dbi_base + PCIE_DBI2_BASE;
> 
> -	if (!ls_pcie_is_bridge(pcie))
> -		return -ENODEV;
> +	pcie->lut = pci->dbi_base + pcie->drvdata->lut_offset;
> 
>  	platform_set_drvdata(pdev, pcie);
> 
> -	ret = ls_add_pcie_port(pcie);
> -	if (ret < 0)
> -		return ret;
> +	if (!ls_pcie_is_bridge(pcie)) {
> +		ret = ls_add_pcie_ep(pcie, pdev);
> +		if (ret < 0)
> +			return ret;
> +	} else {
> +		ret = ls_add_pcie_port(pcie);
> +		if (ret < 0)
> +			return ret;
> +	}
> 
>  	return 0;
We can clean code like this:
if (!ls_pcie_is_bridge(pcie)) 
	ret = ls_add_pcie_ep(pcie, pdev);
 else 
	ret = ls_add_pcie_port(pcie);

return ret;

>  }
> --
> 2.14.1