/*
* pci-rcar-gen2: internal PCI bus support
*
* Copyright (C) 2013 Renesas Solutions Corp.
* Copyright (C) 2013 Cogent Embedded, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_pci.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/sizes.h>
#include <linux/slab.h>
/* AHB-PCI Bridge PCI communication registers */
#define RCAR_AHBPCI_PCICOM_OFFSET 0x800
#define RCAR_PCIAHB_WIN1_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x00)
#define RCAR_PCIAHB_WIN2_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x04)
#define RCAR_PCIAHB_PREFETCH0 0x0
#define RCAR_PCIAHB_PREFETCH4 0x1
#define RCAR_PCIAHB_PREFETCH8 0x2
#define RCAR_PCIAHB_PREFETCH16 0x3
#define RCAR_AHBPCI_WIN1_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x10)
#define RCAR_AHBPCI_WIN2_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x14)
#define RCAR_AHBPCI_WIN_CTR_MEM (3 << 1)
#define RCAR_AHBPCI_WIN_CTR_CFG (5 << 1)
#define RCAR_AHBPCI_WIN1_HOST (1 << 30)
#define RCAR_AHBPCI_WIN1_DEVICE (1 << 31)
#define RCAR_PCI_INT_ENABLE_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x20)
#define RCAR_PCI_INT_STATUS_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x24)
#define RCAR_PCI_INT_SIGTABORT (1 << 0)
#define RCAR_PCI_INT_SIGRETABORT (1 << 1)
#define RCAR_PCI_INT_REMABORT (1 << 2)
#define RCAR_PCI_INT_PERR (1 << 3)
#define RCAR_PCI_INT_SIGSERR (1 << 4)
#define RCAR_PCI_INT_RESERR (1 << 5)
#define RCAR_PCI_INT_WIN1ERR (1 << 12)
#define RCAR_PCI_INT_WIN2ERR (1 << 13)
#define RCAR_PCI_INT_A (1 << 16)
#define RCAR_PCI_INT_B (1 << 17)
#define RCAR_PCI_INT_PME (1 << 19)
#define RCAR_PCI_INT_ALLERRORS (RCAR_PCI_INT_SIGTABORT | \
RCAR_PCI_INT_SIGRETABORT | \
RCAR_PCI_INT_SIGRETABORT | \
RCAR_PCI_INT_REMABORT | \
RCAR_PCI_INT_PERR | \
RCAR_PCI_INT_SIGSERR | \
RCAR_PCI_INT_RESERR | \
RCAR_PCI_INT_WIN1ERR | \
RCAR_PCI_INT_WIN2ERR)
#define RCAR_AHB_BUS_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x30)
#define RCAR_AHB_BUS_MMODE_HTRANS (1 << 0)
#define RCAR_AHB_BUS_MMODE_BYTE_BURST (1 << 1)
#define RCAR_AHB_BUS_MMODE_WR_INCR (1 << 2)
#define RCAR_AHB_BUS_MMODE_HBUS_REQ (1 << 7)
#define RCAR_AHB_BUS_SMODE_READYCTR (1 << 17)
#define RCAR_AHB_BUS_MODE (RCAR_AHB_BUS_MMODE_HTRANS | \
RCAR_AHB_BUS_MMODE_BYTE_BURST | \
RCAR_AHB_BUS_MMODE_WR_INCR | \
RCAR_AHB_BUS_MMODE_HBUS_REQ | \
RCAR_AHB_BUS_SMODE_READYCTR)
#define RCAR_USBCTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x34)
#define RCAR_USBCTR_USBH_RST (1 << 0)
#define RCAR_USBCTR_PCICLK_MASK (1 << 1)
#define RCAR_USBCTR_PLL_RST (1 << 2)
#define RCAR_USBCTR_DIRPD (1 << 8)
#define RCAR_USBCTR_PCIAHB_WIN2_EN (1 << 9)
#define RCAR_USBCTR_PCIAHB_WIN1_256M (0 << 10)
#define RCAR_USBCTR_PCIAHB_WIN1_512M (1 << 10)
#define RCAR_USBCTR_PCIAHB_WIN1_1G (2 << 10)
#define RCAR_USBCTR_PCIAHB_WIN1_2G (3 << 10)
#define RCAR_USBCTR_PCIAHB_WIN1_MASK (3 << 10)
#define RCAR_PCI_ARBITER_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x40)
#define RCAR_PCI_ARBITER_PCIREQ0 (1 << 0)
#define RCAR_PCI_ARBITER_PCIREQ1 (1 << 1)
#define RCAR_PCI_ARBITER_PCIBP_MODE (1 << 12)
#define RCAR_PCI_UNIT_REV_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x48)
struct rcar_pci_priv {
struct device *dev;
void __iomem *reg;
struct resource io_res;
struct resource mem_res;
struct resource *cfg_res;
unsigned busnr;
int irq;
unsigned long window_size;
};
/* PCI configuration space operations */
static void __iomem *rcar_pci_cfg_base(struct pci_bus *bus, unsigned int devfn,
int where)
{
struct pci_sys_data *sys = bus->sysdata;
struct rcar_pci_priv *priv = sys->private_data;
int slot, val;
if (sys->busnr != bus->number || PCI_FUNC(devfn))
return NULL;
/* Only one EHCI/OHCI device built-in */
slot = PCI_SLOT(devfn);
if (slot > 2)
return NULL;
/* bridge logic only has registers to 0x40 */
if (slot == 0x0 && where >= 0x40)
return NULL;
val = slot ? RCAR_AHBPCI_WIN1_DEVICE | RCAR_AHBPCI_WIN_CTR_CFG :
RCAR_AHBPCI_WIN1_HOST | RCAR_AHBPCI_WIN_CTR_CFG;
iowrite32(val, priv->reg + RCAR_AHBPCI_WIN1_CTR_REG);
return priv->reg + (slot >> 1) * 0x100 + where;
}
static int rcar_pci_read_config(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 *val)
{
void __iomem *reg = rcar_pci_cfg_base(bus, devfn, where);
if (!reg)
return PCIBIOS_DEVICE_NOT_FOUND;
switch (size) {
case 1:
*val = ioread8(reg);
break;
case 2:
*val = ioread16(reg);
break;
default:
*val = ioread32(reg);
break;
}
return PCIBIOS_SUCCESSFUL;
}
static int rcar_pci_write_config(struct pci_bus *bus, unsigned int devfn,
int where, int size, u32 val)
{
void __iomem *reg = rcar_pci_cfg_base(bus, devfn, where);
if (!reg)
return PCIBIOS_DEVICE_NOT_FOUND;
switch (size) {
case 1:
iowrite8(val, reg);
break;
case 2:
iowrite16(val, reg);
break;
default:
iowrite32(val, reg);
break;
}
return PCIBIOS_SUCCESSFUL;
}
/* PCI interrupt mapping */
static int rcar_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
{
struct pci_sys_data *sys = dev->bus->sysdata;
struct rcar_pci_priv *priv = sys->private_data;
int irq;
irq = of_irq_parse_and_map_pci(dev, slot, pin);
if (!irq)
irq = priv->irq;
return irq;
}
#ifdef CONFIG_PCI_DEBUG
/* if debug enabled, then attach an error handler irq to the bridge */
static irqreturn_t rcar_pci_err_irq(int irq, void *pw)
{
struct rcar_pci_priv *priv = pw;
u32 status = ioread32(priv->reg + RCAR_PCI_INT_STATUS_REG);
if (status & RCAR_PCI_INT_ALLERRORS) {
dev_err(priv->dev, "error irq: status %08x\n", status);
/* clear the error(s) */
iowrite32(status & RCAR_PCI_INT_ALLERRORS,
priv->reg + RCAR_PCI_INT_STATUS_REG);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static void rcar_pci_setup_errirq(struct rcar_pci_priv *priv)
{
int ret;
u32 val;
ret = devm_request_irq(priv->dev, priv->irq, rcar_pci_err_irq,
IRQF_SHARED, "error irq", priv);
if (ret) {
dev_err(priv->dev, "cannot claim IRQ for error handling\n");
return;
}
val = ioread32(priv->reg + RCAR_PCI_INT_ENABLE_REG);
val |= RCAR_PCI_INT_ALLERRORS;
iowrite32(val, priv->reg + RCAR_PCI_INT_ENABLE_REG);
}
#else
static inline void rcar_pci_setup_errirq(struct rcar_pci_priv *priv) { }
#endif
/* PCI host controller setup */
static int rcar_pci_setup(int nr, struct pci_sys_data *sys)
{
struct rcar_pci_priv *priv = sys->private_data;
void __iomem *reg = priv->reg;
u32 val;
pm_runtime_enable(priv->dev);
pm_runtime_get_sync(priv->dev);
val = ioread32(reg + RCAR_PCI_UNIT_REV_REG);
dev_info(priv->dev, "PCI: bus%u revision %x\n", sys->busnr, val);
/* Disable Direct Power Down State and assert reset */
val = ioread32(reg + RCAR_USBCTR_REG) & ~RCAR_USBCTR_DIRPD;
val |= RCAR_USBCTR_USBH_RST | RCAR_USBCTR_PLL_RST;
iowrite32(val, reg + RCAR_USBCTR_REG);
udelay(4);
/* De-assert reset and reset PCIAHB window1 size */
val &= ~(RCAR_USBCTR_PCIAHB_WIN1_MASK | RCAR_USBCTR_PCICLK_MASK |
RCAR_USBCTR_USBH_RST | RCAR_USBCTR_PLL_RST);
/* Setup PCIAHB window1 size */
switch (priv->window_size) {
case SZ_2G:
val |= RCAR_USBCTR_PCIAHB_WIN1_2G;
break;
case SZ_1G:
val |= RCAR_USBCTR_PCIAHB_WIN1_1G;
break;
case SZ_512M:
val |= RCAR_USBCTR_PCIAHB_WIN1_512M;
break;
default:
pr_warn("unknown window size %ld - defaulting to 256M\n",
priv->window_size);
priv->window_size = SZ_256M;
/* fall-through */
case SZ_256M:
val |= RCAR_USBCTR_PCIAHB_WIN1_256M;
break;
}
iowrite32(val, reg + RCAR_USBCTR_REG);
/* Configure AHB master and slave modes */
iowrite32(RCAR_AHB_BUS_MODE, reg + RCAR_AHB_BUS_CTR_REG);
/* Configure PCI arbiter */
val = ioread32(reg + RCAR_PCI_ARBITER_CTR_REG);
val |= RCAR_PCI_ARBITER_PCIREQ0 | RCAR_PCI_ARBITER_PCIREQ1 |
RC