Re: [RFC 2/2] pci: dwc: pci-exynos: add the codes to support the exynos5433

From: Jingoo Han
Date: Fri Dec 22 2017 - 02:50:05 EST


On Thursday, December 21, 2017 9:21 PM, Jaehoon Chung wrote:
> On 12/22/2017 01:12 AM, Jingoo Han wrote:
> > On Thursday, December 21, 2017 7:14 AM, Jaehoon Chung wrote:
> >>
> >> Exynos5433 has the PCIe for WiFi.
> >> Added the codes relevant to PCIe for supporting the exynos5433.
> >> Also changed the binding documentation name to
> >> 'samsung,exynos-pcie.txt'.
> >> (It's not only exynos5440 anymore.)
> >>
> >
> > I have no objection.
> > However, I added some comments about Exynos5440.
> >
> >> Signed-off-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
> >> ---
> >> ...exynos5440-pcie.txt => samsung,exynos-pcie.txt} | 2 +-
> >> drivers/pci/dwc/pci-exynos.c | 183
> > ++++++++++++++++-----
> >> 2 files changed, 144 insertions(+), 41 deletions(-)
> >> rename Documentation/devicetree/bindings/pci/{samsung,exynos5440-
> pcie.txt
> >> => samsung,exynos-pcie.txt} (97%)
> >>
> >> diff --git a/Documentation/devicetree/bindings/pci/samsung,exynos5440-
> >> pcie.txt b/Documentation/devicetree/bindings/pci/samsung,exynos-
> pcie.txt
> >> similarity index 97%
> >> rename from Documentation/devicetree/bindings/pci/samsung,exynos5440-
> >> pcie.txt
> >> rename to Documentation/devicetree/bindings/pci/samsung,exynos-pcie.txt
> >> index 34a11bfbfb60..958dcc150505 100644
> >> --- a/Documentation/devicetree/bindings/pci/samsung,exynos5440-pcie.txt
> >> +++ b/Documentation/devicetree/bindings/pci/samsung,exynos-pcie.txt
> >> @@ -4,7 +4,7 @@ This PCIe host controller is based on the Synopsys
> >> DesignWare PCIe IP
> >> and thus inherits all the common properties defined in designware-
> >> pcie.txt.
> >>
> >> Required properties:
> >> -- compatible: "samsung,exynos5440-pcie"
> >> +- compatible: "samsung,exynos5440-pcie" or "samsung,exynos5433-pcie"
> >> - reg: base addresses and lengths of the PCIe controller,
> >> the PHY controller, additional register for the PHY controller.
> >> (Registers for the PHY controller are DEPRECATED.
> >> diff --git a/drivers/pci/dwc/pci-exynos.c b/drivers/pci/dwc/pci-
> exynos.c
> >> index 5596fdedbb94..8dee2e90347e 100644
> >> --- a/drivers/pci/dwc/pci-exynos.c
> >> +++ b/drivers/pci/dwc/pci-exynos.c
> >> @@ -40,6 +40,8 @@
> >> #define PCIE_IRQ_SPECIAL 0x008
> >> #define PCIE_IRQ_EN_PULSE 0x00c
> >> #define PCIE_IRQ_EN_LEVEL 0x010
> >> +#define PCIE_SW_WAKE 0x018
> >> +#define PCIE_BUS_EN BIT(1)
> >> #define IRQ_MSI_ENABLE BIT(2)
> >> #define PCIE_IRQ_EN_SPECIAL 0x014
> >> #define PCIE_PWR_RESET 0x018
> >> @@ -49,7 +51,8 @@
> >> #define PCIE_NONSTICKY_RESET 0x024
> >> #define PCIE_APP_INIT_RESET 0x028
> >> #define PCIE_APP_LTSSM_ENABLE 0x02c
> >> -#define PCIE_ELBI_RDLH_LINKUP 0x064
> >> +#define PCIE_ELBI_RDLH_LINKUP 0x074
> >
> > The address of this register should be 0x064 for exynos5440.
> > Howe about the following?
> >
> > +#define EXYNOS5440_PCIE_ELBI_RDLH_LINKUP 0x064
> > +#define PCIE_ELBI_RDLH_LINKUP 0x074
> >
> > Or you can add the following.
> >
> > /* Exynos5440 PCIe ELBI registers */
> > #define EXYNOS5440_PCIE_ELBI_RDLH_LINKUP 0x064
>
> Maybe, you're right. Because i didn't have Exynos5440 TRM, it's problem to
> me about updating other SoCs.
> I have checked almost all variants Exynos. They are using the LINKUP
> register as 0x74.
>
> If i can get the exynos5440 TRM, it's much helpful to me. Is it possible?

I don't have Exynos5440 TRM.
Please ask other guys.

Best regards,
Jingoo Han

>
> >
> >> +#define PCIE_ELBI_XMLH_LINKUP BIT(4)
> >> #define PCIE_ELBI_LTSSM_ENABLE 0x1
> >> #define PCIE_ELBI_SLV_AWMISC 0x11c
> >> #define PCIE_ELBI_SLV_ARMISC 0x120
> >> @@ -94,6 +97,10 @@
> >> #define PCIE_PHY_TRSV3_PD_TSV BIT(7)
> >> #define PCIE_PHY_TRSV3_LVCC 0x31c
> >>
> >> +/* DBI register */
> >> +#define PCIE_MISC_CONTROL_1_OFF 0x8BC
> >> +#define DBI_RO_WR_EN BIT(0)
> >> +
> >> struct exynos_pcie_mem_res {
> >> void __iomem *elbi_base; /* DT 0th resource: PCIe CTRL */
> >> void __iomem *phy_base; /* DT 1st resource: PHY CTRL */
> >> @@ -221,6 +228,96 @@ static const struct exynos_pcie_ops
> >> exynos5440_pcie_ops = {
> >> .deinit_clk_resources = exynos5440_pcie_deinit_clk_resources,
> >> };
> >>
> >> +static int exynos5433_pcie_get_mem_resources(struct platform_device
> > *pdev,
> >> + struct exynos_pcie *ep)
> >> +{
> >> + struct dw_pcie *pci = ep->pci;
> >> + struct device *dev = pci->dev;
> >> + struct resource *res;
> >> +
> >> + ep->mem_res = devm_kzalloc(dev, sizeof(*ep->mem_res), GFP_KERNEL);
> >> + if (!ep->mem_res)
> >> + return -ENOMEM;
> >> +
> >> + /* External Local Bus interface(ELBI) Register */
> >> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "elbi");
> >> + ep->mem_res->elbi_base = devm_ioremap_resource(&pdev->dev, res);
> >> + if (IS_ERR(ep->mem_res->elbi_base))
> >> + return PTR_ERR(ep->mem_res->elbi_base);
> >> +
> >> + /* Data Bus Interface(DBI) Register */
> >> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
> >> + pci->dbi_base = devm_ioremap_resource(&pdev->dev, res);
> >> + if (IS_ERR(pci->dbi_base))
> >> + return PTR_ERR(pci->dbi_base);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int exynos5433_pcie_get_clk_resources(struct exynos_pcie *ep)
> >> +{
> >> + struct dw_pcie *pci = ep->pci;
> >> + struct device *dev = pci->dev;
> >> +
> >> + ep->clk_res = devm_kzalloc(dev, sizeof(*ep->clk_res), GFP_KERNEL);
> >> + if (!ep->clk_res)
> >> + return -ENOMEM;
> >> +
> >> + ep->clk_res->clk = devm_clk_get(dev, "pcie");
> >> + if (IS_ERR(ep->clk_res->clk)) {
> >> + dev_err(dev, "Failed to get pcie rc clock\n");
> >> + return PTR_ERR(ep->clk_res->clk);
> >> + }
> >> +
> >> + ep->clk_res->bus_clk = devm_clk_get(dev, "pcie_bus");
> >> + if (IS_ERR(ep->clk_res->bus_clk)) {
> >> + dev_err(dev, "Failed to get pcie bus clock\n");
> >> + return PTR_ERR(ep->clk_res->bus_clk);
> >> + }
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static void exynos5433_pcie_deinit_clk_resources(struct exynos_pcie
> *ep)
> >> +{
> >> + clk_disable_unprepare(ep->clk_res->bus_clk);
> >> + clk_disable_unprepare(ep->clk_res->clk);
> >> +}
> >> +
> >> +
> >> +static int exynos5433_pcie_init_clk_resources(struct exynos_pcie *ep)
> >> +{
> >> + struct dw_pcie *pci = ep->pci;
> >> + struct device *dev = pci->dev;
> >> + int ret;
> >> +
> >> + ret = clk_prepare_enable(ep->clk_res->clk);
> >> + if (ret) {
> >> + dev_err(dev, "cannot enable pcie rc clock");
> >> + return ret;
> >> + }
> >> +
> >> + ret = clk_prepare_enable(ep->clk_res->bus_clk);
> >> + if (ret) {
> >> + dev_err(dev, "cannot enable pcie bus clock");
> >> + goto err_bus_clk;
> >> + }
> >> +
> >> + return 0;
> >> +
> >> +err_bus_clk:
> >> + clk_disable_unprepare(ep->clk_res->clk);
> >> +
> >> + return ret;
> >> +}
> >> +
> >> +static const struct exynos_pcie_ops exynos5433_pcie_ops = {
> >> + .get_mem_resources = exynos5433_pcie_get_mem_resources,
> >> + .get_clk_resources = exynos5433_pcie_get_clk_resources,
> >> + .init_clk_resources = exynos5433_pcie_init_clk_resources,
> >> + .deinit_clk_resources = exynos5433_pcie_deinit_clk_resources,
> >> +};
> >> +
> >> static void exynos_pcie_writel(void __iomem *base, u32 val, u32 reg)
> >> {
> >> writel(val, base + reg);
> >> @@ -279,7 +376,9 @@ static void exynos_pcie_deassert_core_reset(struct
> >> exynos_pcie *ep)
> >> exynos_pcie_writel(ep->mem_res->elbi_base, 1, PCIE_NONSTICKY_RESET);
> >> exynos_pcie_writel(ep->mem_res->elbi_base, 1, PCIE_APP_INIT_RESET);
> >> exynos_pcie_writel(ep->mem_res->elbi_base, 0, PCIE_APP_INIT_RESET);
> >> - exynos_pcie_writel(ep->mem_res->block_base, 1, PCIE_PHY_MAC_RESET);
> >> + if (ep->mem_res->block_base)
> >> + exynos_pcie_writel(ep->mem_res->block_base, 1,
> >> + PCIE_PHY_MAC_RESET);
> >
> > Good.
> >
> >> }
> >>
> >> static void exynos_pcie_assert_phy_reset(struct exynos_pcie *ep)
> >> @@ -413,9 +512,6 @@ static int exynos_pcie_establish_link(struct
> >> exynos_pcie *ep)
> >> if (ep->using_phy) {
> >> phy_reset(ep->phy);
> >>
> >> - exynos_pcie_writel(ep->mem_res->elbi_base, 1,
> >> - PCIE_PWR_RESET);
> >> -
> >> phy_power_on(ep->phy);
> >> phy_init(ep->phy);
> >> } else {
> >> @@ -430,14 +526,16 @@ static int exynos_pcie_establish_link(struct
> >> exynos_pcie *ep)
> >> udelay(500);
> >> exynos_pcie_writel(ep->mem_res->block_base, 0,
> >> PCIE_PHY_COMMON_RESET);
> >> + exynos_pcie_deassert_core_reset(ep);
> >> }
> >>
> >> - /* pulse for common reset */
> >> - exynos_pcie_writel(ep->mem_res->block_base, 1,
> >> PCIE_PHY_COMMON_RESET);
> >> - udelay(500);
> >> - exynos_pcie_writel(ep->mem_res->block_base, 0,
> >> PCIE_PHY_COMMON_RESET);
> >
> > These codes are also necessary for Exyno5440.
> > How about moving these codes instead of removing them?
> >
> > @@ -430,14 +526,16 @@ static int exynos_pcie_establish_link(struct
> > exynos_pcie *ep)
> > udelay(500);
> > exynos_pcie_writel(ep->mem_res->block_base, 0,
> > PCIE_PHY_COMMON_RESET);
> > + /* pulse for common reset */
> > + exynos_pcie_writel(ep->mem_res->block_base, 1,
> > + PCIE_PHY_COMMON_RESET);
> > + udelay(500);
> > + exynos_pcie_writel(ep->mem_res->block_base, 0,
> > + PCIE_PHY_COMMON_RESET);
> > + exynos_pcie_deassert_core_reset(ep);
> > }
> >
> >
> >> + /*
> >> + * Enable DBI_RO_WR_EN bit.
> >> + * - When set to 1, some RO and HWinit bits are wriatble from
> >> + * the local application through the DBI.
> >> + */
> >> + dw_pcie_writel_dbi(pci, PCIE_MISC_CONTROL_1_OFF, DBI_RO_WR_EN);
> >>
> >> - exynos_pcie_deassert_core_reset(ep);
> >> dw_pcie_setup_rc(pp);
> >> exynos_pcie_assert_reset(ep);
> >>
> >> @@ -472,16 +570,6 @@ static void exynos_pcie_clear_irq_pulse(struct
> >> exynos_pcie *ep)
> >> exynos_pcie_writel(ep->mem_res->elbi_base, val, PCIE_IRQ_PULSE);
> >> }
> >>
> >> -static void exynos_pcie_enable_irq_pulse(struct exynos_pcie *ep)
> >> -{
> >> - u32 val;
> >> -
> >> - /* enable INTX interrupt */
> >> - val = IRQ_INTA_ASSERT | IRQ_INTB_ASSERT |
> >> - IRQ_INTC_ASSERT | IRQ_INTD_ASSERT;
> >> - exynos_pcie_writel(ep->mem_res->elbi_base, val, PCIE_IRQ_EN_PULSE);
> >> -}
> >> -
> >> static irqreturn_t exynos_pcie_irq_handler(int irq, void *arg)
> >> {
> >> struct exynos_pcie *ep = arg;
> >> @@ -513,9 +601,16 @@ static void exynos_pcie_msi_init(struct
> exynos_pcie
> >> *ep)
> >> exynos_pcie_writel(ep->mem_res->elbi_base, val, PCIE_IRQ_EN_LEVEL);
> >> }
> >>
> >> -static void exynos_pcie_enable_interrupts(struct exynos_pcie *ep)
> >> +static void exynos_pcie_enable_irq_pulse(struct exynos_pcie *ep)
> >> {
> >> - exynos_pcie_enable_irq_pulse(ep);
> >> + u32 val;
> >> +
> >> + val = IRQ_INTA_ASSERT | IRQ_INTB_ASSERT |
> >> + IRQ_INTC_ASSERT | IRQ_INTD_ASSERT;
> >> + exynos_pcie_writel(ep->mem_res->elbi_base, val, PCIE_IRQ_EN_PULSE);
> >> +
> >> + exynos_pcie_writel(ep->mem_res->elbi_base, 0, PCIE_IRQ_EN_LEVEL);
> >> + exynos_pcie_writel(ep->mem_res->elbi_base, 0, PCIE_IRQ_EN_SPECIAL);
> >
> > Good.
> >
> >>
> >> if (IS_ENABLED(CONFIG_PCI_MSI))
> >> exynos_pcie_msi_init(ep);
> >> @@ -575,10 +670,8 @@ static int exynos_pcie_link_up(struct dw_pcie *pci)
> >> u32 val;
> >>
> >> val = exynos_pcie_readl(ep->mem_res->elbi_base,
> >> PCIE_ELBI_RDLH_LINKUP);
> >> - if (val == PCIE_ELBI_LTSSM_ENABLE)
> >> - return 1;
> >
> > Exynos5440 uses 'PCIE_ELBI_LTSSM_ENABLE'.
> > Can you keep this code for Exyno5440?
>
> It's possible to keep, but if it has to keep, then it needs to distinguish
> between exynos5440 and other exynos.
> Although I already mentioned, i needs to get Exynos5440 TRM. :)
>
> Best Regards,
> Jaehoon Chung
>
> >
> > This register can be added as below.
> >
> > /* Exynos5440 PCIe ELBI registers */
> > #define EXYNOS5440_PCIE_ELBI_RDLH_LINKUP 0x064
> > #define EXYNOS5440_PCIE_ELBI_LTSSM_ENABLE BIT(0)
> >
> > Best regards,
> > Jingoo Han
> >
> >>
> >> - return 0;
> >> + return (val & PCIE_ELBI_XMLH_LINKUP);
> >> }
> >>
> >> static int exynos_pcie_host_init(struct pcie_port *pp)
> >> @@ -587,7 +680,7 @@ static int exynos_pcie_host_init(struct pcie_port
> *pp)
> >> struct exynos_pcie *ep = to_exynos_pcie(pci);
> >>
> >> exynos_pcie_establish_link(ep);
> >> - exynos_pcie_enable_interrupts(ep);
> >> + exynos_pcie_enable_irq_pulse(ep);
> >>
> >> return 0;
> >> }
> >> @@ -608,8 +701,11 @@ static int __init exynos_add_pcie_port(struct
> >> exynos_pcie *ep,
> >>
> >> pp->irq = platform_get_irq(pdev, 1);
> >> if (pp->irq < 0) {
> >> - dev_err(dev, "failed to get irq\n");
> >> - return pp->irq;
> >> + pp->irq = platform_get_irq_byname(pdev, "intr");
> >> + if (pp->irq < 0) {
> >> + dev_err(dev, "failed to get irq\n");
> >> + return pp->irq;
> >> + }
> >> }
> >> ret = devm_request_irq(dev, pp->irq, exynos_pcie_irq_handler,
> >> IRQF_SHARED, "exynos-pcie", ep);
> >> @@ -678,13 +774,23 @@ static int __init exynos_pcie_probe(struct
> >> platform_device *pdev)
> >>
> >> ep->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0);
> >>
> >> - /* Assume that controller doesn't use the PHY framework */
> >> - ep->using_phy = false;
> >> + /*
> >> + * In case of Exynos5440,
> >> + * Assume that controller doesn't use the PHY frameork.
> >> + * Other SoCs might be used the PHY framework.
> >> + */
> >> +
> >> + if (of_device_is_compatible(np, "samsung,exynos5440-pcie"))
> >> + ep->using_phy = false;
> >>
> >> - ep->phy = devm_of_phy_get(dev, np, NULL);
> >> + ep->phy = devm_of_phy_get(dev, np, "pcie-phy");
> >> if (IS_ERR(ep->phy)) {
> >> if (PTR_ERR(ep->phy) == -EPROBE_DEFER)
> >> return PTR_ERR(ep->phy);
> >> + if (!of_device_is_compatible(np, "samsung,exynos5440-pcie"))
> >> {
> >> + dev_err(dev, "Can't find the pcie-phy\n");
> >> + return PTR_ERR(ep->phy);
> >> + }
> >> dev_warn(dev, "Use the 'phy' property. Current DT of pci-
> >> exynos was deprecated!!\n");
> >> } else
> >> ep->using_phy = true;
> >> @@ -734,23 +840,20 @@ static int __exit exynos_pcie_remove(struct
> >> platform_device *pdev)
> >> static const struct of_device_id exynos_pcie_of_match[] = {
> >> {
> >> .compatible = "samsung,exynos5440-pcie",
> >> - .data = &exynos5440_pcie_ops
> >> + .data = &exynos5440_pcie_ops,
> >> + }, {
> >> + .compatible = "samsung,exynos5433-pcie",
> >> + .data = &exynos5433_pcie_ops,
> >> },
> >> {},
> >> };
> >>
> >> static struct platform_driver exynos_pcie_driver = {
> >> + .probe = exynos_pcie_probe,
> >> .remove = __exit_p(exynos_pcie_remove),
> >> .driver = {
> >> .name = "exynos-pcie",
> >> .of_match_table = exynos_pcie_of_match,
> >> },
> >> };
> >> -
> >> -/* Exynos PCIe driver does not allow module unload */
> >> -
> >> -static int __init exynos_pcie_init(void)
> >> -{
> >> - return platform_driver_probe(&exynos_pcie_driver,
> >> exynos_pcie_probe);
> >> -}
> >> -subsys_initcall(exynos_pcie_init);
> >> +builtin_platform_driver(exynos_pcie_driver);
> >> --
> >> 2.15.1
> >
> >
> >
> >
> >