// SPDX-License-Identifier: GPL-2.0
/*
* PCIe host controller driver for Freescale Layerscape SoCs
*
* Copyright (C) 2014 Freescale Semiconductor.
* Copyright 2021 NXP
*
* Author: Minghuan Lian <[email protected]>
*/
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/iopoll.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include <linux/of_address.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/resource.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include "../../pci.h"
#include "pcie-designware.h"
/* 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 */
/* PF Message Command Register */
#define LS_PCIE_PF_MCR 0x2c
#define PF_MCR_PTOMR BIT(0)
#define PF_MCR_EXL2S BIT(1)
/* LS1021A PEXn PM Write Control Register */
#define SCFG_PEXPMWRCR(idx) (0x5c + (idx) * 0x64)
#define PMXMTTURNOFF BIT(31)
#define SCFG_PEXSFTRSTCR 0x190
#define PEXSR(idx) BIT(idx)
/* LS1043A PEX PME control register */
#define SCFG_PEXPMECR 0x144
#define PEXPME(idx) BIT(31 - (idx) * 4)
/* LS1043A PEX LUT debug register */
#define LS_PCIE_LDBG 0x7fc
#define LDBG_SR BIT(30)
#define LDBG_WE BIT(31)
#define PCIE_IATU_NUM 6
struct ls_pcie_drvdata {
const u32 pf_lut_off;
const struct dw_pcie_host_ops *ops;
int (*exit_from_l2)(struct dw_pcie_rp *pp);
bool scfg_support;
bool pm_support;
};
struct ls_pcie {
struct dw_pcie *pci;
const struct ls_pcie_drvdata *drvdata;
void __iomem *pf_lut_base;
struct regmap *scfg;
int index;
bool big_endian;
};
#define ls_pcie_pf_lut_readl_addr(addr) ls_pcie_pf_lut_readl(pcie, addr)
#define to_ls_pcie(x) dev_get_drvdata((x)->dev)
static bool ls_pcie_is_bridge(struct ls_pcie *pcie)
{
struct dw_pcie *pci = pcie->pci;
u32 header_type;
header_type = ioread8(pci->dbi_base + PCI_HEADER_TYPE);
header_type &= PCI_HEADER_TYPE_MASK;
return header_type == PCI_HEADER_TYPE_BRIDGE;
}
/* Clear multi-function bit */
static void ls_pcie_clear_multifunction(struct ls_pcie *pcie)
{
struct dw_pcie *pci = pcie->pci;
iowrite8(PCI_HEADER_TYPE_BRIDGE, pci->dbi_base + PCI_HEADER_TYPE);
}
/* Drop MSG TLP except for Vendor MSG */
static void ls_pcie_drop_msg_tlp(struct ls_pcie *pcie)
{
u32 val;
struct dw_pcie *pci = pcie->pci;
val = ioread32(pci->dbi_base + PCIE_STRFMR1);
val &= 0xDFFFFFFF;
iowrite32(val, pci->dbi_base + PCIE_STRFMR1);
}
/* Forward error response of outbound non-posted requests */
static void ls_pcie_fix_error_response(struct ls_pcie *pcie)
{
struct dw_pcie *pci = pcie->pci;
iowrite32(PCIE_ABSERR_SETTING, pci->dbi_base + PCIE_ABSERR);
}
static u32 ls_pcie_pf_lut_readl(struct ls_pcie *pcie, u32 off)
{
if (pcie->big_endian)
return ioread32be(pcie->pf_lut_base + off);
return ioread32(pcie->pf_lut_base + off);
}
static void ls_pcie_pf_lut_writel(struct ls_pcie *pcie, u32 off, u32 val)
{
if (pcie->big_endian)
iowrite32be(val, pcie->pf_lut_base + off);
else
iowrite32(val, pcie->pf_lut_base + off);
}
static void ls_pcie_send_turnoff_msg(struct dw_pcie_rp *pp)
{
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
struct ls_pcie *pcie = to_ls_pcie(pci);
u32 val;
int ret;
val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_PF_MCR);
val |= PF_MCR_PTOMR;
ls_pcie_pf_lut_writel(pcie, LS_PCIE_PF_MCR, val);
ret = readx_poll_timeout(ls_pcie_pf_lut_readl_addr, LS_PCIE_PF_MCR,
val, !(val & PF_MCR_PTOMR),
PCIE_PME_TO_L2_TIMEOUT_US/10,
PCIE_PME_TO_L2_TIMEOUT_US);
if (ret)
dev_err(pcie->pci->dev, "PME_Turn_off timeout\n");
}
static int ls_pcie_exit_from_l2(struct dw_pcie_rp *pp)
{
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
struct ls_pcie *pcie = to_ls_pcie(pci);
u32 val;
int ret;
/*
* Set PF_MCR_EXL2S bit in LS_PCIE_PF_MCR register for the link
* to exit L2 state.
*/
val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_PF_MCR);
val |= PF_MCR_EXL2S;
ls_pcie_pf_lut_writel(pcie, LS_PCIE_PF_MCR, val);
/*
* L2 exit timeout of 10ms is not defined in the specifications,
* it was chosen based on empirical observations.
*/
ret = readx_poll_timeout(ls_pcie_pf_lut_readl_addr, LS_PCIE_PF_MCR,
val, !(val & PF_MCR_EXL2S),
1000,
10000);
if (ret)
dev_err(pcie->pci->dev, "L2 exit timeout\n");
return ret;
}
static int ls_pcie_host_init(struct dw_pcie_rp *pp)
{
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
struct ls_pcie *pcie = to_ls_pcie(pci);
ls_pcie_fix_error_response(pcie);
dw_pcie_dbi_ro_wr_en(pci);
ls_pcie_clear_multifunction(pcie);
dw_pcie_dbi_ro_wr_dis(pci);
ls_pcie_drop_msg_tlp(pcie);
return 0;
}
static void scfg_pcie_send_turnoff_msg(struct regmap *scfg, u32 reg, u32 mask)
{
/* Send PME_Turn_Off message */
regmap_write_bits(scfg, reg, mask, mask);
/*
* There is no specific register to check for PME_To_Ack from endpoint.
* So on the safe side, wait for PCIE_PME_TO_L2_TIMEOUT_US.
*/
mdelay(PCIE_PME_TO_L2_TIMEOUT_US/1000);
/*
* Layerscape hardware reference manual recommends clearing the PMXMTTURNOFF bit
* to complete the PME_Turn_Off handshake.
*/
regmap_write_bits(scfg, reg, mask, 0);
}
static void ls1021a_pcie_send_turnoff_msg(struct dw_pcie_rp *pp)
{
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
struct ls_pcie *pcie = to_ls_pcie(pci);
scfg_pcie_send_turnoff_msg(pcie->scfg, SCFG_PEXPMWRCR(pcie->index), PMXMTTURNOFF);
}
static int scfg_pcie_exit_from_l2(struct regmap *scfg, u32 reg, u32 mask)
{
/* Reset the PEX wrapper to bring the link out of L2 */
regmap_write_bits(scfg, reg, mask, mask);
regmap_write_bits(scfg, reg, mask, 0);
return 0;
}
static int ls1021a_pcie_exit_from_l2(struct dw_pcie_rp *pp)
{
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
struct ls_pcie *pcie = to_ls_pcie(pci);
return scfg_pcie_exit_from_l2(pcie->scfg, SCFG_PEXSFTRSTCR, PEXSR(pcie->index));
}
static void ls1043a_pcie_send_turnoff_msg(struct dw_pcie_rp *pp)
{
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
struct ls_pcie *pcie = to_ls_pcie(pci);
scfg_pcie_send_turnoff_msg(pcie->scfg, SCFG_PEXPMECR, PEXPME(pcie->index));
}
static int ls1043a_pcie_exit_from_l2(struct dw_pcie_rp *pp)
{
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
struct ls_pcie *pcie = to_ls_pcie(pci);
u32 val;
/*
* Reset the PEX wrapper to bring the link out of L2.
* LDBG_WE: allows the user to have write access to the PEXDBG[SR] for both setting and
* clearing the soft reset on the PEX module.
* LDBG_SR: When SR is set to 1, the PEX module enters soft reset.
*/
val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_LDBG);
val |= LDBG_WE;
ls_pcie_pf_lut_writel(pcie, LS_PCIE_LDBG, val);
val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_LDBG);
val |= LDBG_SR;
ls_pcie_pf_lut_writel(pcie, LS_PCIE_LDBG, val);
val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_LDBG);
val &= ~LDBG_SR;
ls_pcie_pf_lut_writel(pcie, LS_PCIE_LDBG, val);
val = ls_pcie_pf_lut_readl(pcie, LS_PCIE_LDBG);
val &= ~LDBG_WE;
ls_pcie_pf_lut_writel(pcie, LS_PCIE_LDBG, val);
return 0;
}
static const struct dw_pcie_host_ops ls_pcie_host_ops = {
.init = ls_pcie_host_init,
.pme_turn_off = ls_pcie_send_turnoff_msg,
};
static const struct dw_pcie_host_ops ls1021a_pcie_host_ops = {
.init = ls_pcie_host_init,
.pme_turn_off = ls1021a_pcie_send_turnoff_msg,
};
static const struct ls_pcie_drvdata ls1021a_drvdata = {
.pm_support = true,
.scfg_support = true,
.ops = &ls1021a_pcie_host_ops,
.exit_from_l2 = ls1021a_pcie_exit_from_l2,
};
static const struct dw_pcie_host_ops ls1043a_pcie_host_ops = {
.init = ls_pcie_host_init,
.pme_turn_off = ls1043a_pcie_send_turnoff_msg,
};
static const struct ls_pcie_drvdata ls1043a_drvdata = {
.pf_lut_off = 0x10000,
.pm_support = true,
.scfg_support = true,
.ops = &ls1043a_pcie_host_ops,
.exit_from_l2 = ls1043a_pcie_exit_from_l2,
};
static const struct ls_pcie_drvdata layerscape_drvdata = {
.pf_lut_off = 0xc0000,
.pm_support = true,
.ops = &ls_pcie_host_ops,
.exit_from_l2 = ls_pcie_exit_from_l2,
};
static const struct of_device_id ls_pcie_of_match[] = {
{ .compatible = "fsl,ls1012a-pcie", .data = &layerscape_drvdata },
{ .compatible = "fsl,ls1021a-pcie", .data = &ls1021a_drvdata },
{ .compatible = "fsl,ls1028a-pcie", .data = &layerscape_drvdata },
{ .compatible = "fsl,ls1043a-pcie", .data = &ls1043a_drvdata },
{ .compatible = "fsl,ls1046a-pcie", .data = &layerscape_drvdata },
{ .compatible = "fsl,ls2080a-pcie", .data = &layerscape_drvdata },
{ .compatible = "fsl,ls2085a-pcie", .data = &layerscape_drvdata },
{ .compatible = "fsl,ls2088a-pcie", .data = &layerscape_drvdata },
{ .compatible = "fsl,ls1088a-pcie", .data = &layerscape_drvdata },
{ },
};
static int ls_pcie_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct dw_pcie *pci;
struct ls_pcie *pcie;
struct resource *dbi_base;
u32 index[2];
int ret;
pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
if (!pcie)
return -ENOMEM;
pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
if (!pci)
return -ENOMEM;
pcie->drvdata = of_device_get_match_data(dev);
pci->dev = dev;
pcie->pci = pci;
pci->pp.ops = pcie->drvdata->ops;
dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
pci->dbi_base = devm_pci_remap_cfg_resource(dev, dbi_base);
if (IS_ERR(pci->dbi_base))
return PTR_ERR(pci->dbi_base);
pcie->big_endian = of_property_read_bool(dev->of_node, "big-endian");
pcie->pf_lut_base = pci->dbi_base + pcie->drvdata->pf_lut_off;
if (pcie->drvdata->scfg_support) {
pcie->scfg = syscon_regmap_lookup_by_phandle(dev->of_node, "fsl,pcie-scfg");
if (IS_ERR(pcie->scfg)) {
dev_err(dev, "No syscfg phandle specified\n");
return PTR_ERR(pcie->scfg);
}
ret = of_property_read_u32_array(dev->of_node, "fsl,pcie-scfg", index, 2);
if (ret)
return ret;
pcie->index = index[1];
}
if (!ls_pcie_is_bridge(pcie))
return -ENODEV;
platform_set_drvdata(pdev, pcie);
return dw_pcie_host_init(&pci->pp);
}
static int ls_pcie_suspend_noirq(struct device *dev)
{
struct ls_pcie *pcie = dev_get_drvdata(dev);
if (!pcie->drvdata->pm_support)
return 0;
return dw_pcie_suspend_noirq(pcie->pci);
}
static int ls_pcie_resume_noirq(struct device *dev)
{
struct ls_pcie *pcie = dev_get_drvdata(dev);
int ret;
if (!pcie->drvdata->pm_support)
return 0;
ret = pcie->drvdata->exit_from_l2(&pcie->pci->pp);
if (ret)
return ret;
return dw_pcie_resume_noirq(pcie->pci);
}
static const struct dev_pm_ops ls_pcie_pm_ops = {
NOIRQ_SYSTEM_SLEEP_PM_OPS(ls_pcie_suspend_noirq, ls_pcie_resume_noirq)
};
static struct platform_driver ls_pcie_driver = {
.probe = ls_pcie_probe,
.driver = {
.name = "layerscape-pcie",
.of_match_table = ls_pcie_of_match,
.suppress_bind_attrs = true,
.pm = &ls_pcie_pm_ops,
},
};
builtin_platform_driver(ls_pcie_driver);
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