// SPDX-License-Identifier: GPL-2.0
/*
* PCIe host controller driver for Marvell Armada-8K SoCs
*
* Armada-8K PCIe Glue Layer Source Code
*
* Copyright (C) 2016 Marvell Technology Group Ltd.
*
* Author: Yehuda Yitshak <[email protected]>
* Author: Shadi Ammouri <[email protected]>
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/pci.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/resource.h>
#include <linux/of_pci.h>
#include "pcie-designware.h"
#define ARMADA8K_PCIE_MAX_LANES PCIE_LNK_X4
struct armada8k_pcie {
struct dw_pcie *pci;
struct clk *clk;
struct clk *clk_reg;
struct phy *phy[ARMADA8K_PCIE_MAX_LANES];
unsigned int phy_count;
};
#define PCIE_VENDOR_REGS_OFFSET 0x8000
#define PCIE_GLOBAL_CONTROL_REG (PCIE_VENDOR_REGS_OFFSET + 0x0)
#define PCIE_APP_LTSSM_EN BIT(2)
#define PCIE_DEVICE_TYPE_SHIFT 4
#define PCIE_DEVICE_TYPE_MASK 0xF
#define PCIE_DEVICE_TYPE_RC 0x4 /* Root complex */
#define PCIE_GLOBAL_STATUS_REG (PCIE_VENDOR_REGS_OFFSET + 0x8)
#define PCIE_GLB_STS_RDLH_LINK_UP BIT(1)
#define PCIE_GLB_STS_PHY_LINK_UP BIT(9)
#define PCIE_GLOBAL_INT_CAUSE1_REG (PCIE_VENDOR_REGS_OFFSET + 0x1C)
#define PCIE_GLOBAL_INT_MASK1_REG (PCIE_VENDOR_REGS_OFFSET + 0x20)
#define PCIE_INT_A_ASSERT_MASK BIT(9)
#define PCIE_INT_B_ASSERT_MASK BIT(10)
#define PCIE_INT_C_ASSERT_MASK BIT(11)
#define PCIE_INT_D_ASSERT_MASK BIT(12)
#define PCIE_ARCACHE_TRC_REG (PCIE_VENDOR_REGS_OFFSET + 0x50)
#define PCIE_AWCACHE_TRC_REG (PCIE_VENDOR_REGS_OFFSET + 0x54)
#define PCIE_ARUSER_REG (PCIE_VENDOR_REGS_OFFSET + 0x5C)
#define PCIE_AWUSER_REG (PCIE_VENDOR_REGS_OFFSET + 0x60)
/*
* AR/AW Cache defaults: Normal memory, Write-Back, Read / Write
* allocate
*/
#define ARCACHE_DEFAULT_VALUE 0x3511
#define AWCACHE_DEFAULT_VALUE 0x5311
#define DOMAIN_OUTER_SHAREABLE 0x2
#define AX_USER_DOMAIN_MASK 0x3
#define AX_USER_DOMAIN_SHIFT 4
#define to_armada8k_pcie(x) dev_get_drvdata((x)->dev)
static void armada8k_pcie_disable_phys(struct armada8k_pcie *pcie)
{
int i;
for (i = 0; i < ARMADA8K_PCIE_MAX_LANES; i++) {
phy_power_off(pcie->phy[i]);
phy_exit(pcie->phy[i]);
}
}
static int armada8k_pcie_enable_phys(struct armada8k_pcie *pcie)
{
int ret;
int i;
for (i = 0; i < ARMADA8K_PCIE_MAX_LANES; i++) {
ret = phy_init(pcie->phy[i]);
if (ret)
return ret;
ret = phy_set_mode_ext(pcie->phy[i], PHY_MODE_PCIE,
pcie->phy_count);
if (ret) {
phy_exit(pcie->phy[i]);
return ret;
}
ret = phy_power_on(pcie->phy[i]);
if (ret) {
phy_exit(pcie->phy[i]);
return ret;
}
}
return 0;
}
static int armada8k_pcie_setup_phys(struct armada8k_pcie *pcie)
{
struct dw_pcie *pci = pcie->pci;
struct device *dev = pci->dev;
struct device_node *node = dev->of_node;
int ret = 0;
int i;
for (i = 0; i < ARMADA8K_PCIE_MAX_LANES; i++) {
pcie->phy[i] = devm_of_phy_get_by_index(dev, node, i);
if (IS_ERR(pcie->phy[i])) {
if (PTR_ERR(pcie->phy[i]) != -ENODEV)
return PTR_ERR(pcie->phy[i]);
pcie->phy[i] = NULL;
continue;
}
pcie->phy_count++;
}
/* Old bindings miss the PHY handle, so just warn if there is no PHY */
if (!pcie->phy_count)
dev_warn(dev, "No available PHY\n");
ret = armada8k_pcie_enable_phys(pcie);
if (ret)
dev_err(dev, "Failed to initialize PHY(s) (%d)\n", ret);
return ret;
}
static int armada8k_pcie_link_up(struct dw_pcie *pci)
{
u32 reg;
u32 mask = PCIE_GLB_STS_RDLH_LINK_UP | PCIE_GLB_STS_PHY_LINK_UP;
reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_STATUS_REG);
if ((reg & mask) == mask)
return 1;
dev_dbg(pci->dev, "No link detected (Global-Status: 0x%08x).\n", reg);
return 0;
}
static int armada8k_pcie_start_link(struct dw_pcie *pci)
{
u32 reg;
/* Start LTSSM */
reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_CONTROL_REG);
reg |= PCIE_APP_LTSSM_EN;
dw_pcie_writel_dbi(pci, PCIE_GLOBAL_CONTROL_REG, reg);
return 0;
}
static int armada8k_pcie_host_init(struct dw_pcie_rp *pp)
{
u32 reg;
struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
if (!dw_pcie_link_up(pci)) {
/* Disable LTSSM state machine to enable configuration */
reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_CONTROL_REG);
reg &= ~(PCIE_APP_LTSSM_EN);
dw_pcie_writel_dbi(pci, PCIE_GLOBAL_CONTROL_REG, reg);
}
/* Set the device to root complex mode */
reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_CONTROL_REG);
reg &= ~(PCIE_DEVICE_TYPE_MASK << PCIE_DEVICE_TYPE_SHIFT);
reg |= PCIE_DEVICE_TYPE_RC << PCIE_DEVICE_TYPE_SHIFT;
dw_pcie_writel_dbi(pci, PCIE_GLOBAL_CONTROL_REG, reg);
/* Set the PCIe master AxCache attributes */
dw_pcie_writel_dbi(pci, PCIE_ARCACHE_TRC_REG, ARCACHE_DEFAULT_VALUE);
dw_pcie_writel_dbi(pci, PCIE_AWCACHE_TRC_REG, AWCACHE_DEFAULT_VALUE);
/* Set the PCIe master AxDomain attributes */
reg = dw_pcie_readl_dbi(pci, PCIE_ARUSER_REG);
reg &= ~(AX_USER_DOMAIN_MASK << AX_USER_DOMAIN_SHIFT);
reg |= DOMAIN_OUTER_SHAREABLE << AX_USER_DOMAIN_SHIFT;
dw_pcie_writel_dbi(pci, PCIE_ARUSER_REG, reg);
reg = dw_pcie_readl_dbi(pci, PCIE_AWUSER_REG);
reg &= ~(AX_USER_DOMAIN_MASK << AX_USER_DOMAIN_SHIFT);
reg |= DOMAIN_OUTER_SHAREABLE << AX_USER_DOMAIN_SHIFT;
dw_pcie_writel_dbi(pci, PCIE_AWUSER_REG, reg);
/* Enable INT A-D interrupts */
reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_INT_MASK1_REG);
reg |= PCIE_INT_A_ASSERT_MASK | PCIE_INT_B_ASSERT_MASK |
PCIE_INT_C_ASSERT_MASK | PCIE_INT_D_ASSERT_MASK;
dw_pcie_writel_dbi(pci, PCIE_GLOBAL_INT_MASK1_REG, reg);
return 0;
}
static irqreturn_t armada8k_pcie_irq_handler(int irq, void *arg)
{
struct armada8k_pcie *pcie = arg;
struct dw_pcie *pci = pcie->pci;
u32 val;
/*
* Interrupts are directly handled by the device driver of the
* PCI device. However, they are also latched into the PCIe
* controller, so we simply discard them.
*/
val = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_INT_CAUSE1_REG);
dw_pcie_writel_dbi(pci, PCIE_GLOBAL_INT_CAUSE1_REG, val);
return IRQ_HANDLED;
}
static const struct dw_pcie_host_ops armada8k_pcie_host_ops = {
.init = armada8k_pcie_host_init,
};
static int armada8k_add_pcie_port(struct armada8k_pcie *pcie,
struct platform_device *pdev)
{
struct dw_pcie *pci = pcie->pci;
struct dw_pcie_rp *pp = &pci->pp;
struct device *dev = &pdev->dev;
int ret;
pp->ops = &armada8k_pcie_host_ops;
pp->irq = platform_get_irq(pdev, 0);
if (pp->irq < 0)
return pp->irq;
ret = devm_request_irq(dev, pp->irq, armada8k_pcie_irq_handler,
IRQF_SHARED, "armada8k-pcie", pcie);
if (ret) {
dev_err(dev, "failed to request irq %d\n", pp->irq);
return ret;
}
ret = dw_pcie_host_init(pp);
if (ret) {
dev_err(dev, "failed to initialize host: %d\n", ret);
return ret;
}
return 0;
}
static const struct dw_pcie_ops dw_pcie_ops = {
.link_up = armada8k_pcie_link_up,
.start_link = armada8k_pcie_start_link,
};
static int armada8k_pcie_probe(struct platform_device *pdev)
{
struct dw_pcie *pci;
struct armada8k_pcie *pcie;
struct device *dev = &pdev->dev;
struct resource *base;
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;
pci->dev = dev;
pci->ops = &dw_pcie_ops;
pcie->pci = pci;
pcie->clk = devm_clk_get(dev, NULL);
if (IS_ERR(pcie->clk))
return PTR_ERR(pcie->clk);
ret = clk_prepare_enable(pcie->clk);
if (ret)
return ret;
pcie->clk_reg = devm_clk_get(dev, "reg");
if (pcie->clk_reg == ERR_PTR(-EPROBE_DEFER)) {
ret = -EPROBE_DEFER;
goto fail;
}
if (!IS_ERR(pcie->clk_reg)) {
ret = clk_prepare_enable(pcie->clk_reg);
if (ret)
goto fail_clkreg;
}
/* Get the dw-pcie unit configuration/control registers base. */
base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ctrl");
pci->dbi_base = devm_pci_remap_cfg_resource(dev, base);
if (IS_ERR(pci->dbi_base)) {
ret = PTR_ERR(pci->dbi_base);
goto fail_clkreg;
}
ret = armada8k_pcie_setup_phys(pcie);
if (ret)
goto fail_clkreg;
platform_set_drvdata(pdev, pcie);
ret = armada8k_add_pcie_port(pcie, pdev);
if (ret)
goto disable_phy;
return 0;
disable_phy:
armada8k_pcie_disable_phys(pcie);
fail_clkreg:
clk_disable_unprepare(pcie->clk_reg);
fail:
clk_disable_unprepare(pcie->clk);
return ret;
}
static const struct of_device_id armada8k_pcie_of_match[] = {
{ .compatible = "marvell,armada8k-pcie", },
{},
};
static struct platform_driver armada8k_pcie_driver = {
.probe = armada8k_pcie_probe,
.driver = {
.name = "armada8k-pcie",
.of_match_table = armada8k_pcie_of_match,
.suppress_bind_attrs = true,
},
};
builtin_platform_driver(armada8k_pcie_driver);
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