PCI: layerscape: Change to use the DWC common link-up check function

The current Layerscape PCIe driver directly uses the physical layer
LTSSM code to check the link-up state, which treats the > L0 states
as link-up. This is not correct, since there is not explicit map
between link-up state and LTSSM. So this patch changes to use the
DWC common link-up check function.

Link: https://lore.kernel.org/r/20211224094000.8513-1-Zhiqiang.Hou@nxp.com
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>

Author: Zhiqiang-Hou

drivers/pci/controller/dwc/pci-layerscape.c

@@ -3,6 +3,7 @@
  * PCIe host controller driver for Freescale Layerscape SoCs
  *
  * Copyright (C) 2014 Freescale Semiconductor.
+ * Copyright 2021 NXP
  *
  * Author: Minghuan Lian <Minghuan.Lian@freescale.com>
  */
@@ -22,33 +23,15 @@
 
 #include "pcie-designware.h"
 
-/* PEX1/2 Misc Ports Status Register */
-#define SCFG_PEXMSCPORTSR(pex_idx)	(0x94 + (pex_idx) * 4)
-#define LTSSM_STATE_SHIFT	20
-#define LTSSM_STATE_MASK	0x3f
-#define LTSSM_PCIE_L0		0x11 /* L0 state */
-
 /* PEX Internal Configuration Registers */
 #define PCIE_STRFMR1		0x71c /* Symbol Timer & Filter Mask Register1 */
 #define PCIE_ABSERR		0x8d0 /* Bridge Slave Error Response Register */
 #define PCIE_ABSERR_SETTING	0x9401 /* Forward error of non-posted request */
 
 #define PCIE_IATU_NUM		6
 
-struct ls_pcie_drvdata {
-	u32 lut_offset;
-	u32 ltssm_shift;
-	u32 lut_dbg;
-	const struct dw_pcie_host_ops *ops;
-	const struct dw_pcie_ops *dw_pcie_ops;
-};
-
 struct ls_pcie {
 	struct dw_pcie *pci;
-	void __iomem *lut;
-	struct regmap *scfg;
-	const struct ls_pcie_drvdata *drvdata;
-	int index;
 };
 
 #define to_ls_pcie(x)	dev_get_drvdata((x)->dev)
@@ -83,38 +66,6 @@ static void ls_pcie_drop_msg_tlp(struct ls_pcie *pcie)
 	iowrite32(val, pci->dbi_base + PCIE_STRFMR1);
 }
 
-static int ls1021_pcie_link_up(struct dw_pcie *pci)
-{
-	u32 state;
-	struct ls_pcie *pcie = to_ls_pcie(pci);
-
-	if (!pcie->scfg)
-		return 0;
-
-	regmap_read(pcie->scfg, SCFG_PEXMSCPORTSR(pcie->index), &state);
-	state = (state >> LTSSM_STATE_SHIFT) & LTSSM_STATE_MASK;
-
-	if (state < LTSSM_PCIE_L0)
-		return 0;
-
-	return 1;
-}
-
-static int ls_pcie_link_up(struct dw_pcie *pci)
-{
-	struct ls_pcie *pcie = to_ls_pcie(pci);
-	u32 state;
-
-	state = (ioread32(pcie->lut + pcie->drvdata->lut_dbg) >>
-		 pcie->drvdata->ltssm_shift) &
-		 LTSSM_STATE_MASK;
-
-	if (state < LTSSM_PCIE_L0)
-		return 0;
-
-	return 1;
-}
-
 /* Forward error response of outbound non-posted requests */
 static void ls_pcie_fix_error_response(struct ls_pcie *pcie)
 {
@@ -139,96 +90,20 @@ static int ls_pcie_host_init(struct pcie_port *pp)
 	return 0;
 }
 
-static int ls1021_pcie_host_init(struct pcie_port *pp)
-{
-	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
-	struct ls_pcie *pcie = to_ls_pcie(pci);
-	struct device *dev = pci->dev;
-	u32 index[2];
-	int ret;
-
-	pcie->scfg = syscon_regmap_lookup_by_phandle(dev->of_node,
-						     "fsl,pcie-scfg");
-	if (IS_ERR(pcie->scfg)) {
-		ret = PTR_ERR(pcie->scfg);
-		dev_err(dev, "No syscfg phandle specified\n");
-		pcie->scfg = NULL;
-		return ret;
-	}
-
-	if (of_property_read_u32_array(dev->of_node,
-				       "fsl,pcie-scfg", index, 2)) {
-		pcie->scfg = NULL;
-		return -EINVAL;
-	}
-	pcie->index = index[1];
-
-	return ls_pcie_host_init(pp);
-}
-
-static const struct dw_pcie_host_ops ls1021_pcie_host_ops = {
-	.host_init = ls1021_pcie_host_init,
-};
-
 static const struct dw_pcie_host_ops ls_pcie_host_ops = {
 	.host_init = ls_pcie_host_init,
 };
 
-static const struct dw_pcie_ops dw_ls1021_pcie_ops = {
-	.link_up = ls1021_pcie_link_up,
-};
-
-static const struct dw_pcie_ops dw_ls_pcie_ops = {
-	.link_up = ls_pcie_link_up,
-};
-
-static const struct ls_pcie_drvdata ls1021_drvdata = {
-	.ops = &ls1021_pcie_host_ops,
-	.dw_pcie_ops = &dw_ls1021_pcie_ops,
-};
-
-static const struct ls_pcie_drvdata ls1043_drvdata = {
-	.lut_offset = 0x10000,
-	.ltssm_shift = 24,
-	.lut_dbg = 0x7fc,
-	.ops = &ls_pcie_host_ops,
-	.dw_pcie_ops = &dw_ls_pcie_ops,
-};
-
-static const struct ls_pcie_drvdata ls1046_drvdata = {
-	.lut_offset = 0x80000,
-	.ltssm_shift = 24,
-	.lut_dbg = 0x407fc,
-	.ops = &ls_pcie_host_ops,
-	.dw_pcie_ops = &dw_ls_pcie_ops,
-};
-
-static const struct ls_pcie_drvdata ls2080_drvdata = {
-	.lut_offset = 0x80000,
-	.ltssm_shift = 0,
-	.lut_dbg = 0x7fc,
-	.ops = &ls_pcie_host_ops,
-	.dw_pcie_ops = &dw_ls_pcie_ops,
-};
-
-static const struct ls_pcie_drvdata ls2088_drvdata = {
-	.lut_offset = 0x80000,
-	.ltssm_shift = 0,
-	.lut_dbg = 0x407fc,
-	.ops = &ls_pcie_host_ops,
-	.dw_pcie_ops = &dw_ls_pcie_ops,
-};
-
 static const struct of_device_id ls_pcie_of_match[] = {
-	{ .compatible = "fsl,ls1012a-pcie", .data = &ls1046_drvdata },
-	{ .compatible = "fsl,ls1021a-pcie", .data = &ls1021_drvdata },
-	{ .compatible = "fsl,ls1028a-pcie", .data = &ls2088_drvdata },
-	{ .compatible = "fsl,ls1043a-pcie", .data = &ls1043_drvdata },
-	{ .compatible = "fsl,ls1046a-pcie", .data = &ls1046_drvdata },
-	{ .compatible = "fsl,ls2080a-pcie", .data = &ls2080_drvdata },
-	{ .compatible = "fsl,ls2085a-pcie", .data = &ls2080_drvdata },
-	{ .compatible = "fsl,ls2088a-pcie", .data = &ls2088_drvdata },
-	{ .compatible = "fsl,ls1088a-pcie", .data = &ls2088_drvdata },
+	{ .compatible = "fsl,ls1012a-pcie", },
+	{ .compatible = "fsl,ls1021a-pcie", },
+	{ .compatible = "fsl,ls1028a-pcie", },
+	{ .compatible = "fsl,ls1043a-pcie", },
+	{ .compatible = "fsl,ls1046a-pcie", },
+	{ .compatible = "fsl,ls2080a-pcie", },
+	{ .compatible = "fsl,ls2085a-pcie", },
+	{ .compatible = "fsl,ls2088a-pcie", },
+	{ .compatible = "fsl,ls1088a-pcie", },
 	{ },
 };
 
@@ -247,11 +122,8 @@ static int ls_pcie_probe(struct platform_device *pdev)
 	if (!pci)
 		return -ENOMEM;
 
-	pcie->drvdata = of_device_get_match_data(dev);
-
 	pci->dev = dev;
-	pci->ops = pcie->drvdata->dw_pcie_ops;
-	pci->pp.ops = pcie->drvdata->ops;
+	pci->pp.ops = &ls_pcie_host_ops;
 
 	pcie->pci = pci;
 
@@ -260,8 +132,6 @@ static int 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;
-
 	if (!ls_pcie_is_bridge(pcie))
 		return -ENODEV;