5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Frank Li <Frank.Li@xxxxxxx> [ Upstream commit 061cbfab09fb35898f2907d42f936cf9ae271d93 ] Layerscape has PME interrupt, which can be used as linkup notifier. Set CFG_READY bit of PEX_PF0_CONFIG to enable accesses from root complex when linkup detected. Link: https://lore.kernel.org/r/20230515151049.2797105-1-Frank.Li@xxxxxxx Signed-off-by: Xiaowei Bao <xiaowei.bao@xxxxxxx> Signed-off-by: Frank Li <Frank.Li@xxxxxxx> Signed-off-by: Lorenzo Pieralisi <lpieralisi@xxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Stable-dep-of: 17cf8661ee0f ("PCI: layerscape: Add workaround for lost link capabilities during reset") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- .../pci/controller/dwc/pci-layerscape-ep.c | 100 +++++++++++++++++- 1 file changed, 99 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c b/drivers/pci/controller/dwc/pci-layerscape-ep.c index ad99707b3b994..5b27554e071a1 100644 --- a/drivers/pci/controller/dwc/pci-layerscape-ep.c +++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c @@ -18,6 +18,20 @@ #include "pcie-designware.h" +#define PEX_PF0_CONFIG 0xC0014 +#define PEX_PF0_CFG_READY BIT(0) + +/* PEX PFa PCIE PME and message interrupt registers*/ +#define PEX_PF0_PME_MES_DR 0xC0020 +#define PEX_PF0_PME_MES_DR_LUD BIT(7) +#define PEX_PF0_PME_MES_DR_LDD BIT(9) +#define PEX_PF0_PME_MES_DR_HRD BIT(10) + +#define PEX_PF0_PME_MES_IER 0xC0028 +#define PEX_PF0_PME_MES_IER_LUDIE BIT(7) +#define PEX_PF0_PME_MES_IER_LDDIE BIT(9) +#define PEX_PF0_PME_MES_IER_HRDIE BIT(10) + #define to_ls_pcie_ep(x) dev_get_drvdata((x)->dev) struct ls_pcie_ep_drvdata { @@ -30,8 +44,84 @@ struct ls_pcie_ep { struct dw_pcie *pci; struct pci_epc_features *ls_epc; const struct ls_pcie_ep_drvdata *drvdata; + int irq; + bool big_endian; }; +static u32 ls_lut_readl(struct ls_pcie_ep *pcie, u32 offset) +{ + struct dw_pcie *pci = pcie->pci; + + if (pcie->big_endian) + return ioread32be(pci->dbi_base + offset); + else + return ioread32(pci->dbi_base + offset); +} + +static void ls_lut_writel(struct ls_pcie_ep *pcie, u32 offset, u32 value) +{ + struct dw_pcie *pci = pcie->pci; + + if (pcie->big_endian) + iowrite32be(value, pci->dbi_base + offset); + else + iowrite32(value, pci->dbi_base + offset); +} + +static irqreturn_t ls_pcie_ep_event_handler(int irq, void *dev_id) +{ + struct ls_pcie_ep *pcie = dev_id; + struct dw_pcie *pci = pcie->pci; + u32 val, cfg; + + val = ls_lut_readl(pcie, PEX_PF0_PME_MES_DR); + ls_lut_writel(pcie, PEX_PF0_PME_MES_DR, val); + + if (!val) + return IRQ_NONE; + + if (val & PEX_PF0_PME_MES_DR_LUD) { + cfg = ls_lut_readl(pcie, PEX_PF0_CONFIG); + cfg |= PEX_PF0_CFG_READY; + ls_lut_writel(pcie, PEX_PF0_CONFIG, cfg); + dw_pcie_ep_linkup(&pci->ep); + + dev_dbg(pci->dev, "Link up\n"); + } else if (val & PEX_PF0_PME_MES_DR_LDD) { + dev_dbg(pci->dev, "Link down\n"); + } else if (val & PEX_PF0_PME_MES_DR_HRD) { + dev_dbg(pci->dev, "Hot reset\n"); + } + + return IRQ_HANDLED; +} + +static int ls_pcie_ep_interrupt_init(struct ls_pcie_ep *pcie, + struct platform_device *pdev) +{ + u32 val; + int ret; + + pcie->irq = platform_get_irq_byname(pdev, "pme"); + if (pcie->irq < 0) + return pcie->irq; + + ret = devm_request_irq(&pdev->dev, pcie->irq, ls_pcie_ep_event_handler, + IRQF_SHARED, pdev->name, pcie); + if (ret) { + dev_err(&pdev->dev, "Can't register PCIe IRQ\n"); + return ret; + } + + /* Enable interrupts */ + val = ls_lut_readl(pcie, PEX_PF0_PME_MES_IER); + val |= PEX_PF0_PME_MES_IER_LDDIE | PEX_PF0_PME_MES_IER_HRDIE | + PEX_PF0_PME_MES_IER_LUDIE; + ls_lut_writel(pcie, PEX_PF0_PME_MES_IER, val); + + return 0; +} + static const struct pci_epc_features* ls_pcie_ep_get_features(struct dw_pcie_ep *ep) { @@ -124,6 +214,7 @@ static int __init ls_pcie_ep_probe(struct platform_device *pdev) struct ls_pcie_ep *pcie; struct pci_epc_features *ls_epc; struct resource *dbi_base; + int ret; pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL); if (!pcie) @@ -143,6 +234,7 @@ static int __init ls_pcie_ep_probe(struct platform_device *pdev) pci->ops = pcie->drvdata->dw_pcie_ops; ls_epc->bar_fixed_64bit = (1 << BAR_2) | (1 << BAR_4); + ls_epc->linkup_notifier = true; pcie->pci = pci; pcie->ls_epc = ls_epc; @@ -154,9 +246,15 @@ static int __init ls_pcie_ep_probe(struct platform_device *pdev) pci->ep.ops = &ls_pcie_ep_ops; + pcie->big_endian = of_property_read_bool(dev->of_node, "big-endian"); + platform_set_drvdata(pdev, pcie); - return dw_pcie_ep_init(&pci->ep); + ret = dw_pcie_ep_init(&pci->ep); + if (ret) + return ret; + + return ls_pcie_ep_interrupt_init(pcie, pdev); } static struct platform_driver ls_pcie_ep_driver = { -- 2.40.1
