[PATCH v1 09/10] PCI: imx6: Add iMX8MM PCIe EP mode
From: Richard Zhu
Date: Tue Jul 19 2022 - 06:01:55 EST
Based on i.MX8MM platforms, add the i.MX8MM PCIe EP mode support.
Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
---
drivers/pci/controller/dwc/pci-imx6.c | 148 +++++++++++++++++++++++---
1 file changed, 134 insertions(+), 14 deletions(-)
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 655240ce60e0..ba4ac258c13d 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -51,6 +51,7 @@ enum imx6_pcie_variants {
IMX7D,
IMX8MQ,
IMX8MM,
+ IMX8MM_EP,
};
#define IMX6_PCIE_FLAG_IMX6_PHY BIT(0)
@@ -59,6 +60,7 @@ enum imx6_pcie_variants {
struct imx6_pcie_drvdata {
enum imx6_pcie_variants variant;
+ enum dw_pcie_device_mode mode;
u32 flags;
int dbi_length;
};
@@ -150,23 +152,27 @@ struct imx6_pcie {
static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
{
WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ &&
- imx6_pcie->drvdata->variant != IMX8MM);
+ imx6_pcie->drvdata->variant != IMX8MM &&
+ imx6_pcie->drvdata->variant != IMX8MM_EP);
return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14;
}
static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie)
{
- unsigned int mask, val;
+ unsigned int mask, val, mode;
+
+ if (imx6_pcie->drvdata->mode == DW_PCIE_EP_TYPE)
+ mode = PCI_EXP_TYPE_ENDPOINT;
+ else
+ mode = PCI_EXP_TYPE_ROOT_PORT;
if (imx6_pcie->drvdata->variant == IMX8MQ &&
imx6_pcie->controller_id == 1) {
mask = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE;
- val = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
- PCI_EXP_TYPE_ROOT_PORT);
+ val = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE, mode);
} else {
mask = IMX6Q_GPR12_DEVICE_TYPE;
- val = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE,
- PCI_EXP_TYPE_ROOT_PORT);
+ val = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE, mode);
}
regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val);
@@ -301,6 +307,7 @@ static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
{
switch (imx6_pcie->drvdata->variant) {
case IMX8MM:
+ case IMX8MM_EP:
/*
* The PHY initialization had been done in the PHY
* driver, break here directly.
@@ -557,6 +564,7 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
case IMX7D:
break;
case IMX8MM:
+ case IMX8MM_EP:
case IMX8MQ:
ret = clk_prepare_enable(imx6_pcie->pcie_aux);
if (ret) {
@@ -601,6 +609,7 @@ static void imx6_pcie_disable_ref_clk(struct imx6_pcie *imx6_pcie)
IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
break;
case IMX8MM:
+ case IMX8MM_EP:
case IMX8MQ:
clk_disable_unprepare(imx6_pcie->pcie_aux);
break;
@@ -669,6 +678,7 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
reset_control_assert(imx6_pcie->pciephy_reset);
fallthrough;
case IMX8MM:
+ case IMX8MM_EP:
reset_control_assert(imx6_pcie->apps_reset);
break;
case IMX6SX:
@@ -744,6 +754,7 @@ static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
break;
case IMX6Q: /* Nothing to do */
case IMX8MM:
+ case IMX8MM_EP:
break;
}
@@ -793,6 +804,7 @@ static void imx6_pcie_ltssm_enable(struct device *dev)
case IMX7D:
case IMX8MQ:
case IMX8MM:
+ case IMX8MM_EP:
reset_control_deassert(imx6_pcie->apps_reset);
break;
}
@@ -812,6 +824,7 @@ static void imx6_pcie_ltssm_disable(struct device *dev)
case IMX7D:
case IMX8MQ:
case IMX8MM:
+ case IMX8MM_EP:
reset_control_assert(imx6_pcie->apps_reset);
break;
}
@@ -992,8 +1005,102 @@ static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
static const struct dw_pcie_ops dw_pcie_ops = {
.start_link = imx6_pcie_start_link,
+ .stop_link = imx6_pcie_stop_link,
};
+static void imx6_pcie_ep_init(struct dw_pcie_ep *ep)
+{
+ enum pci_barno bar;
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ for (bar = BAR_0; bar <= BAR_5; bar++)
+ dw_pcie_ep_reset_bar(pci, bar);
+}
+
+static int imx6_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
+ enum pci_epc_irq_type type,
+ u16 interrupt_num)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ switch (type) {
+ case PCI_EPC_IRQ_LEGACY:
+ return dw_pcie_ep_raise_legacy_irq(ep, func_no);
+ case PCI_EPC_IRQ_MSI:
+ return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
+ case PCI_EPC_IRQ_MSIX:
+ return dw_pcie_ep_raise_msix_irq(ep, func_no, interrupt_num);
+ default:
+ dev_err(pci->dev, "UNKNOWN IRQ type\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static const struct pci_epc_features imx8m_pcie_epc_features = {
+ .linkup_notifier = false,
+ .msi_capable = true,
+ .msix_capable = false,
+ .reserved_bar = 1 << BAR_1 | 1 << BAR_3,
+ .align = SZ_64K,
+};
+
+static const struct pci_epc_features*
+imx6_pcie_ep_get_features(struct dw_pcie_ep *ep)
+{
+ return &imx8m_pcie_epc_features;
+}
+
+static const struct dw_pcie_ep_ops pcie_ep_ops = {
+ .ep_init = imx6_pcie_ep_init,
+ .raise_irq = imx6_pcie_ep_raise_irq,
+ .get_features = imx6_pcie_ep_get_features,
+};
+
+static int imx6_add_pcie_ep(struct imx6_pcie *imx6_pcie,
+ struct platform_device *pdev)
+{
+ int ret;
+ unsigned int pcie_dbi2_offset;
+ struct dw_pcie_ep *ep;
+ struct resource *res;
+ struct dw_pcie *pci = imx6_pcie->pci;
+ struct pcie_port *pp = &pci->pp;
+ struct device *dev = pci->dev;
+
+ imx6_pcie_host_init(pp);
+ ep = &pci->ep;
+ ep->ops = &pcie_ep_ops;
+
+ switch (imx6_pcie->drvdata->variant) {
+ case IMX8MM_EP:
+ pcie_dbi2_offset = SZ_1M;
+ break;
+ default:
+ pcie_dbi2_offset = SZ_4K;
+ break;
+ }
+ pci->dbi_base2 = pci->dbi_base + pcie_dbi2_offset;
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "addr_space");
+ if (!res)
+ return -EINVAL;
+
+ ep->phys_base = res->start;
+ ep->addr_size = resource_size(res);
+ ep->page_size = SZ_64K;
+
+ ret = dw_pcie_ep_init(ep);
+ if (ret) {
+ dev_err(dev, "failed to initialize endpoint\n");
+ return ret;
+ }
+ /* Start LTSSM. */
+ imx6_pcie_ltssm_enable(dev);
+
+ return 0;
+}
+
#ifdef CONFIG_PM_SLEEP
static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
{
@@ -1181,6 +1288,7 @@ static int imx6_pcie_probe(struct platform_device *pdev)
}
break;
case IMX8MM:
+ case IMX8MM_EP:
imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
if (IS_ERR(imx6_pcie->pcie_aux))
return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
@@ -1269,15 +1377,22 @@ static int imx6_pcie_probe(struct platform_device *pdev)
if (ret)
return ret;
- ret = dw_pcie_host_init(&pci->pp);
- if (ret < 0)
- return ret;
+ if (imx6_pcie->drvdata->mode == DW_PCIE_EP_TYPE) {
+ ret = imx6_add_pcie_ep(imx6_pcie, pdev);
+ if (ret < 0)
+ return ret;
+ } else {
+ ret = dw_pcie_host_init(&pci->pp);
+ if (ret < 0)
+ return ret;
- if (pci_msi_enabled()) {
- u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
- val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
- val |= PCI_MSI_FLAGS_ENABLE;
- dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
+ if (pci_msi_enabled()) {
+ u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
+
+ val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
+ val |= PCI_MSI_FLAGS_ENABLE;
+ dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
+ }
}
return 0;
@@ -1322,6 +1437,10 @@ static const struct imx6_pcie_drvdata drvdata[] = {
.variant = IMX8MM,
.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
},
+ [IMX8MM_EP] = {
+ .variant = IMX8MM_EP,
+ .mode = DW_PCIE_EP_TYPE,
+ },
};
static const struct of_device_id imx6_pcie_of_match[] = {
@@ -1331,6 +1450,7 @@ static const struct of_device_id imx6_pcie_of_match[] = {
{ .compatible = "fsl,imx7d-pcie", .data = &drvdata[IMX7D], },
{ .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], },
{ .compatible = "fsl,imx8mm-pcie", .data = &drvdata[IMX8MM], },
+ { .compatible = "fsl,imx8mm-pcie-ep", .data = &drvdata[IMX8MM_EP], },
{},
};
--
2.25.1