// SPDX-License-Identifier: GPL-2.0
/*
* PCIe host controller driver for Freescale i.MX6 SoCs
*
* Copyright (C) 2013 Kosagi
* http://www.kosagi.com
*
* Author: Sean Cross <xobs@kosagi.com>
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
#include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
#include <linux/module.h>
#include <linux/of_gpio.h>
#include <linux/of_device.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/resource.h>
#include <linux/signal.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/reset.h>
#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include "pcie-designware.h"
#define to_imx6_pcie(x) dev_get_drvdata((x)->dev)
enum imx6_pcie_variants {
IMX6Q,
IMX6SX,
IMX6QP,
IMX7D,
};
struct imx6_pcie {
struct dw_pcie *pci;
int reset_gpio;
bool gpio_active_high;
struct clk *pcie_bus;
struct clk *pcie_phy;
struct clk *pcie_inbound_axi;
struct clk *pcie;
struct regmap *iomuxc_gpr;
struct reset_control *pciephy_reset;
struct reset_control *apps_reset;
struct reset_control *turnoff_reset;
enum imx6_pcie_variants variant;
u32 tx_deemph_gen1;
u32 tx_deemph_gen2_3p5db;
u32 tx_deemph_gen2_6db;
u32 tx_swing_full;
u32 tx_swing_low;
int link_gen;
struct regulator *vpcie;
/* power domain for pcie */
struct device *pd_pcie;
/* power domain for pcie phy */
struct device *pd_pcie_phy;
};
/* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
#define PHY_PLL_LOCK_WAIT_MAX_RETRIES 2000
#define PHY_PLL_LOCK_WAIT_USLEEP_MIN 50
#define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200
/* PCIe Root Complex registers (memory-mapped) */
#define PCIE_RC_IMX6_MSI_CAP 0x50
#define PCIE_RC_LCR 0x7c
#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1 0x1
#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2 0x2
#define PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK 0xf
#define PCIE_RC_LCSR 0x80
/* PCIe Port Logic registers (memory-mapped) */
#define PL_OFFSET 0x700
#define PCIE_PL_PFLR (PL_OFFSET + 0x08)
#define PCIE_PL_PFLR_LINK_STATE_MASK (0x3f << 16)
#define PCIE_PL_PFLR_FORCE_LINK (1 << 15)
#define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
#define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
#define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
#define PCIE_PHY_CTRL_DATA_LOC 0
#define PCIE_PHY_CTRL_CAP_ADR_LOC 16
#define PCIE_PHY_CTRL_CAP_DAT_LOC 17
#define PCIE_PHY_CTRL_WR_LOC 18
#define PCIE_PHY_CTRL_RD_LOC 19
#define PCIE_PHY_STAT (PL_OFFSET + 0x110)
#define PCIE_PHY_STAT_ACK_LOC 16
#define PCIE_LINK_WIDTH_SPEED_CONTROL 0x80C
#define PORT_LOGIC_SPEED_CHANGE (0x1 << 17)
/* PHY registers (not memory-mapped) */
#define PCIE_PHY_ATEOVRD 0x10
#define PCIE_PHY_ATEOVRD_EN (0x1 << 2)
#define PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT 0
#define PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK 0x1
#define PCIE_PHY_MPLL_OVRD_IN_LO 0x11
#define PCIE_PHY_MPLL_MULTIPLIER_SHIFT 2
#define PCIE_PHY_MPLL_MULTIPLIER_MASK 0x7f
#define PCIE_PHY_MPLL_MULTIPLIER_OVRD (0x1 << 9)
#define PCIE_PHY_RX_ASIC_OUT 0x100D
#define PCIE_PHY_RX_ASIC_OUT_VALID (1 << 0)
#define PHY_RX_OVRD_IN_LO 0x1005
#define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5)
#define PHY_RX_OVRD_IN_LO_RX_PLL_EN (1 << 3)
static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, int exp_val)
{
struct dw_pcie *pci = imx6_pcie->pci;
u32 val;
u32 max_iterations = 10;
u32 wait_counter = 0;
do {
val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT);
val = (val >> PCIE_PHY_STAT_ACK_LOC) & 0x1;
wait_counter++;
if (val == exp_val)
return 0;
udelay(1);
} while (wait_counter < max_iterations);
return -ETIMEDOUT;
}
static int pcie_phy_wait_ack(struct imx6_pcie *imx6_pcie, int addr)
{
struct dw_pcie *pci = imx6_pcie->pci;
u32 val;
int ret;
val = addr << PCIE_PHY_CTRL_DATA_LOC;
dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
val |= (0x1 << PCIE_PHY_CTRL_CAP_ADR_LOC);
dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
ret = pcie_phy_poll_ack(imx6_pcie, 1);
if (ret)
return ret;
val = addr << PCIE_PHY_CTRL_DATA_LOC;
dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
return pcie_phy_poll_ack(imx6_pcie, 0);
}
/* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int