Re: [PATCH v2 1/5] PCI: mediatek: Add a structure to abstract the controller generations

[Honghui Zhang <honghui.zhang@mediatek.com>]

On Thu, 2017-07-27 at 11:19 +0800, Honghui Zhang wrote:
> On Thu, 2017-07-27 at 10:58 +0800, honghui.zhang@mediatek.com wrote:
> > From: Ryder Lee <ryder.lee@mediatek.com>
> > 
> > Introduce a structure "mtk_pcie_soc" to abstract the differences between
> > controller generations, and the .startup() hook is used to encapsulate
> > some SoC-dependent related setting. In doing so, the common code which
> > will be reused by future chips.
> > 
> > In addition, we change the approaches to waiting Gen2 training by using
> > readl_poll_timeout() calls.
> > 
> > Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
> > Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com>
> > ---
> >  drivers/pci/host/pcie-mediatek.c | 81 +++++++++++++++++++++++-----------------
> >  1 file changed, 47 insertions(+), 34 deletions(-)
> > 
> > diff --git a/drivers/pci/host/pcie-mediatek.c b/drivers/pci/host/pcie-mediatek.c
> > index 5a9d858..7f952a4 100644
> > --- a/drivers/pci/host/pcie-mediatek.c
> > +++ b/drivers/pci/host/pcie-mediatek.c
> > @@ -16,6 +16,7 @@
> >  
> 
> Sorry about the disturb, I send the wrong patch for this one.
> I will resend the right version for this last patch.
> 

Sorry, I reply to the wrong patch mail.
I meant to re-send the patch:
[PATCH v2 5/5] dt-bindings: PCI: add support for new generation
controller, not this one.

This one is the right patch.

tahnks.

> thanks.
> >  #include <linux/clk.h>
> >  #include <linux/delay.h>
> > +#include <linux/iopoll.h>
> >  #include <linux/kernel.h>
> >  #include <linux/of_address.h>
> >  #include <linux/of_pci.h>
> > @@ -63,6 +64,18 @@
> >  #define PCIE_FC_CREDIT_MASK	(GENMASK(31, 31) | GENMASK(28, 16))
> >  #define PCIE_FC_CREDIT_VAL(x)	((x) << 16)
> >  
> > +struct mtk_pcie_port;
> > +
> > +/**
> > + * struct mtk_pcie_soc - differentiate between host generations
> > + * @ops: pointer to configuration access functions
> > + * @startup: pointer to controller setting functions
> > + */
> > +struct mtk_pcie_soc {
> > +	struct pci_ops *ops;
> > +	int (*startup)(struct mtk_pcie_port *port);
> > +};
> > +
> >  /**
> >   * struct mtk_pcie_port - PCIe port information
> >   * @base: IO mapped register base
> > @@ -96,6 +109,7 @@ struct mtk_pcie_port {
> >   * @busn: bus range
> >   * @offset: IO / Memory offset
> >   * @ports: pointer to PCIe port information
> > + * @soc: pointer to SoC-dependent operations
> >   */
> >  struct mtk_pcie {
> >  	struct device *dev;
> > @@ -111,13 +125,9 @@ struct mtk_pcie {
> >  		resource_size_t io;
> >  	} offset;
> >  	struct list_head ports;
> > +	const struct mtk_pcie_soc *soc;
> >  };
> >  
> > -static inline bool mtk_pcie_link_up(struct mtk_pcie_port *port)
> > -{
> > -	return !!(readl(port->base + PCIE_LINK_STATUS) & PCIE_PORT_LINKUP);
> > -}
> > -
> >  static void mtk_pcie_subsys_powerdown(struct mtk_pcie *pcie)
> >  {
> >  	struct device *dev = pcie->dev;
> > @@ -171,12 +181,30 @@ static struct pci_ops mtk_pcie_ops = {
> >  	.write = pci_generic_config_write,
> >  };
> >  
> > -static void mtk_pcie_configure_rc(struct mtk_pcie_port *port)
> > +static int mtk_pcie_startup_ports(struct mtk_pcie_port *port)
> >  {
> >  	struct mtk_pcie *pcie = port->pcie;
> >  	u32 func = PCI_FUNC(port->index << 3);
> >  	u32 slot = PCI_SLOT(port->index << 3);
> >  	u32 val;
> > +	int err;
> > +
> > +	/* assert port PERST_N */
> > +	val = readl(pcie->base + PCIE_SYS_CFG);
> > +	val |= PCIE_PORT_PERST(port->index);
> > +	writel(val, pcie->base + PCIE_SYS_CFG);
> > +
> > +	/* de-assert port PERST_N */
> > +	val = readl(pcie->base + PCIE_SYS_CFG);
> > +	val &= ~PCIE_PORT_PERST(port->index);
> > +	writel(val, pcie->base + PCIE_SYS_CFG);
> > +
> > +	/* 100ms timeout value should be enough for Gen1/2 training */
> > +	err = readl_poll_timeout(port->base + PCIE_LINK_STATUS, val,
> > +				 !!(val & PCIE_PORT_LINKUP), 20,
> > +				 100 * USEC_PER_MSEC);
> > +	if (err)
> > +		return -ETIMEDOUT;
> >  
> >  	/* enable interrupt */
> >  	val = readl(pcie->base + PCIE_INT_ENABLE);
> > @@ -209,30 +237,14 @@ static void mtk_pcie_configure_rc(struct mtk_pcie_port *port)
> >  	writel(PCIE_CONF_ADDR(PCIE_FTS_NUM, func, slot, 0),
> >  	       pcie->base + PCIE_CFG_ADDR);
> >  	writel(val, pcie->base + PCIE_CFG_DATA);
> > -}
> >  
> > -static void mtk_pcie_assert_ports(struct mtk_pcie_port *port)
> > -{
> > -	struct mtk_pcie *pcie = port->pcie;
> > -	u32 val;
> > -
> > -	/* assert port PERST_N */
> > -	val = readl(pcie->base + PCIE_SYS_CFG);
> > -	val |= PCIE_PORT_PERST(port->index);
> > -	writel(val, pcie->base + PCIE_SYS_CFG);
> > -
> > -	/* de-assert port PERST_N */
> > -	val = readl(pcie->base + PCIE_SYS_CFG);
> > -	val &= ~PCIE_PORT_PERST(port->index);
> > -	writel(val, pcie->base + PCIE_SYS_CFG);
> > -
> > -	/* PCIe v2.0 need at least 100ms delay to train from Gen1 to Gen2 */
> > -	msleep(100);
> > +	return 0;
> >  }
> >  
> >  static void mtk_pcie_enable_ports(struct mtk_pcie_port *port)
> >  {
> > -	struct device *dev = port->pcie->dev;
> > +	struct mtk_pcie *pcie = port->pcie;
> > +	struct device *dev = pcie->dev;
> >  	int err;
> >  
> >  	err = clk_prepare_enable(port->sys_ck);
> > @@ -250,13 +262,8 @@ static void mtk_pcie_enable_ports(struct mtk_pcie_port *port)
> >  		goto err_phy_on;
> >  	}
> >  
> > -	mtk_pcie_assert_ports(port);
> > -
> > -	/* if link up, then setup root port configuration space */
> > -	if (mtk_pcie_link_up(port)) {
> > -		mtk_pcie_configure_rc(port);
> > +	if (!pcie->soc->startup(port))
> >  		return;
> > -	}
> >  
> >  	dev_info(dev, "Port%d link down\n", port->index);
> >  
> > @@ -480,7 +487,7 @@ static int mtk_pcie_register_host(struct pci_host_bridge *host)
> >  
> >  	host->busnr = pcie->busn.start;
> >  	host->dev.parent = pcie->dev;
> > -	host->ops = &mtk_pcie_ops;
> > +	host->ops = pcie->soc->ops;
> >  	host->map_irq = of_irq_parse_and_map_pci;
> >  	host->swizzle_irq = pci_common_swizzle;
> >  
> > @@ -513,6 +520,7 @@ static int mtk_pcie_probe(struct platform_device *pdev)
> >  	pcie = pci_host_bridge_priv(host);
> >  
> >  	pcie->dev = dev;
> > +	pcie->soc = of_device_get_match_data(dev);
> >  	platform_set_drvdata(pdev, pcie);
> >  	INIT_LIST_HEAD(&pcie->ports);
> >  
> > @@ -537,9 +545,14 @@ static int mtk_pcie_probe(struct platform_device *pdev)
> >  	return err;
> >  }
> >  
> > +static struct mtk_pcie_soc mtk_pcie_soc_v1 = {
> > +	.ops = &mtk_pcie_ops,
> > +	.startup = mtk_pcie_startup_ports,
> > +};
> > +
> >  static const struct of_device_id mtk_pcie_ids[] = {
> > -	{ .compatible = "mediatek,mt7623-pcie"},
> > -	{ .compatible = "mediatek,mt2701-pcie"},
> > +	{ .compatible = "mediatek,mt2701-pcie", .data = &mtk_pcie_soc_v1 },
> > +	{ .compatible = "mediatek,mt7623-pcie", .data = &mtk_pcie_soc_v1 },
> >  	{},
> >  };
> >  
> 
> 
> 
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