diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/pci/controller/pci-rcar-gen2.c | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/drivers/pci/controller/pci-rcar-gen2.c b/drivers/pci/controller/pci-rcar-gen2.c new file mode 100644 index 000000000..afde4aa8f --- /dev/null +++ b/drivers/pci/controller/pci-rcar-gen2.c @@ -0,0 +1,342 @@ +// 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); |