linux/drivers/pci/controller/pci-rcar-gen2.c
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00

343 lines
9.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* pci-rcar-gen2: internal PCI bus support
*
* Copyright (C) 2013 Renesas Solutions Corp.
* Copyright (C) 2013 Cogent Embedded, Inc.
*
* Author: Valentine Barshak <valentine.barshak@cogentembedded.com>
*/
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of_address.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>
#include "../pci.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_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 mem_res;
struct resource *cfg_res;
int irq;
};
/* PCI configuration space operations */
static void __iomem *rcar_pci_cfg_base(struct pci_bus *bus, unsigned int devfn,
int where)
{
struct rcar_pci_priv *priv = bus->sysdata;
int slot, val;
if (!pci_is_root_bus(bus) || 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;
}
#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;
struct device *dev = priv->dev;
u32 status = ioread32(priv->reg + RCAR_PCI_INT_STATUS_REG);
if (status & RCAR_PCI_INT_ALLERRORS) {
dev_err(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)
{
struct device *dev = priv->dev;
int ret;
u32 val;
ret = devm_request_irq(dev, priv->irq, rcar_pci_err_irq,
IRQF_SHARED, "error irq", priv);
if (ret) {
dev_err(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 void rcar_pci_setup(struct rcar_pci_priv *priv)
{
struct pci_host_bridge *bridge = pci_host_bridge_from_priv(priv);
struct device *dev = priv->dev;
void __iomem *reg = priv->reg;
struct resource_entry *entry;
unsigned long window_size;
unsigned long window_addr;
unsigned long window_pci;
u32 val;
entry = resource_list_first_type(&bridge->dma_ranges, IORESOURCE_MEM);
if (!entry) {
window_addr = 0x40000000;
window_pci = 0x40000000;
window_size = SZ_1G;
} else {
window_addr = entry->res->start;
window_pci = entry->res->start - entry->offset;
window_size = resource_size(entry->res);
}
pm_runtime_enable(dev);
pm_runtime_get_sync(dev);
val = ioread32(reg + RCAR_PCI_UNIT_REV_REG);
dev_info(dev, "PCI: revision %x\n", 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 (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",
window_size);
window_size = SZ_256M;
fallthrough;
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 |
RCAR_PCI_ARBITER_PCIBP_MODE;
iowrite32(val, reg + RCAR_PCI_ARBITER_CTR_REG);
/* PCI-AHB mapping */
iowrite32(window_addr | RCAR_PCIAHB_PREFETCH16,
reg + RCAR_PCIAHB_WIN1_CTR_REG);
/* AHB-PCI mapping: OHCI/EHCI registers */
val = priv->mem_res.start | RCAR_AHBPCI_WIN_CTR_MEM;
iowrite32(val, reg + RCAR_AHBPCI_WIN2_CTR_REG);
/* Enable AHB-PCI bridge PCI configuration access */
iowrite32(RCAR_AHBPCI_WIN1_HOST | RCAR_AHBPCI_WIN_CTR_CFG,
reg + RCAR_AHBPCI_WIN1_CTR_REG);
/* Set PCI-AHB Window1 address */
iowrite32(window_pci | PCI_BASE_ADDRESS_MEM_PREFETCH,
reg + PCI_BASE_ADDRESS_1);
/* Set AHB-PCI bridge PCI communication area address */
val = priv->cfg_res->start + RCAR_AHBPCI_PCICOM_OFFSET;
iowrite32(val, reg + PCI_BASE_ADDRESS_0);
val = ioread32(reg + PCI_COMMAND);
val |= PCI_COMMAND_SERR | PCI_COMMAND_PARITY |
PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
iowrite32(val, reg + PCI_COMMAND);
/* Enable PCI interrupts */
iowrite32(RCAR_PCI_INT_A | RCAR_PCI_INT_B | RCAR_PCI_INT_PME,
reg + RCAR_PCI_INT_ENABLE_REG);
rcar_pci_setup_errirq(priv);
}
static struct pci_ops rcar_pci_ops = {
.map_bus = rcar_pci_cfg_base,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
};
static int rcar_pci_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *cfg_res, *mem_res;
struct rcar_pci_priv *priv;
struct pci_host_bridge *bridge;
void __iomem *reg;
bridge = devm_pci_alloc_host_bridge(dev, sizeof(*priv));
if (!bridge)
return -ENOMEM;
priv = pci_host_bridge_priv(bridge);
bridge->sysdata = priv;
cfg_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
reg = devm_ioremap_resource(dev, cfg_res);
if (IS_ERR(reg))
return PTR_ERR(reg);
mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (!mem_res || !mem_res->start)
return -ENODEV;
if (mem_res->start & 0xFFFF)
return -EINVAL;
priv->mem_res = *mem_res;
priv->cfg_res = cfg_res;
priv->irq = platform_get_irq(pdev, 0);
priv->reg = reg;
priv->dev = dev;
if (priv->irq < 0) {
dev_err(dev, "no valid irq found\n");
return priv->irq;
}
bridge->ops = &rcar_pci_ops;
pci_add_flags(PCI_REASSIGN_ALL_BUS);
rcar_pci_setup(priv);
return pci_host_probe(bridge);
}
static const struct of_device_id rcar_pci_of_match[] = {
{ .compatible = "renesas,pci-r8a7790", },
{ .compatible = "renesas,pci-r8a7791", },
{ .compatible = "renesas,pci-r8a7794", },
{ .compatible = "renesas,pci-rcar-gen2", },
{ },
};
static struct platform_driver rcar_pci_driver = {
.driver = {
.name = "pci-rcar-gen2",
.suppress_bind_attrs = true,
.of_match_table = rcar_pci_of_match,
},
.probe = rcar_pci_probe,
};
builtin_platform_driver(rcar_pci_driver);