diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/mips/pci/pci-alchemy.c | 536 |
1 files changed, 536 insertions, 0 deletions
diff --git a/arch/mips/pci/pci-alchemy.c b/arch/mips/pci/pci-alchemy.c new file mode 100644 index 000000000..1c722dd0c --- /dev/null +++ b/arch/mips/pci/pci-alchemy.c @@ -0,0 +1,536 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Alchemy PCI host mode support. + * + * Copyright 2001-2003, 2007-2008 MontaVista Software Inc. + * Author: MontaVista Software, Inc. <source@mvista.com> + * + * Support for all devices (greater than 16) added by David Gathright. + */ + +#include <linux/clk.h> +#include <linux/export.h> +#include <linux/types.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/syscore_ops.h> +#include <linux/vmalloc.h> +#include <linux/dma-map-ops.h> /* for dma_default_coherent */ + +#include <asm/mach-au1x00/au1000.h> +#include <asm/tlbmisc.h> + +#ifdef CONFIG_PCI_DEBUG +#define DBG(x...) printk(KERN_DEBUG x) +#else +#define DBG(x...) do {} while (0) +#endif + +#define PCI_ACCESS_READ 0 +#define PCI_ACCESS_WRITE 1 + +struct alchemy_pci_context { + struct pci_controller alchemy_pci_ctrl; /* leave as first member! */ + void __iomem *regs; /* ctrl base */ + /* tools for wired entry for config space access */ + unsigned long last_elo0; + unsigned long last_elo1; + int wired_entry; + struct vm_struct *pci_cfg_vm; + + unsigned long pm[12]; + + int (*board_map_irq)(const struct pci_dev *d, u8 slot, u8 pin); + int (*board_pci_idsel)(unsigned int devsel, int assert); +}; + +/* for syscore_ops. There's only one PCI controller on Alchemy chips, so this + * should suffice for now. + */ +static struct alchemy_pci_context *__alchemy_pci_ctx; + + +/* IO/MEM resources for PCI. Keep the memres in sync with fixup_bigphys_addr + * in arch/mips/alchemy/common/setup.c + */ +static struct resource alchemy_pci_def_memres = { + .start = ALCHEMY_PCI_MEMWIN_START, + .end = ALCHEMY_PCI_MEMWIN_END, + .name = "PCI memory space", + .flags = IORESOURCE_MEM +}; + +static struct resource alchemy_pci_def_iores = { + .start = ALCHEMY_PCI_IOWIN_START, + .end = ALCHEMY_PCI_IOWIN_END, + .name = "PCI IO space", + .flags = IORESOURCE_IO +}; + +static void mod_wired_entry(int entry, unsigned long entrylo0, + unsigned long entrylo1, unsigned long entryhi, + unsigned long pagemask) +{ + unsigned long old_pagemask; + unsigned long old_ctx; + + /* Save old context and create impossible VPN2 value */ + old_ctx = read_c0_entryhi() & MIPS_ENTRYHI_ASID; + old_pagemask = read_c0_pagemask(); + write_c0_index(entry); + write_c0_pagemask(pagemask); + write_c0_entryhi(entryhi); + write_c0_entrylo0(entrylo0); + write_c0_entrylo1(entrylo1); + tlb_write_indexed(); + write_c0_entryhi(old_ctx); + write_c0_pagemask(old_pagemask); +} + +static void alchemy_pci_wired_entry(struct alchemy_pci_context *ctx) +{ + ctx->wired_entry = read_c0_wired(); + add_wired_entry(0, 0, (unsigned long)ctx->pci_cfg_vm->addr, PM_4K); + ctx->last_elo0 = ctx->last_elo1 = ~0; +} + +static int config_access(unsigned char access_type, struct pci_bus *bus, + unsigned int dev_fn, unsigned char where, u32 *data) +{ + struct alchemy_pci_context *ctx = bus->sysdata; + unsigned int device = PCI_SLOT(dev_fn); + unsigned int function = PCI_FUNC(dev_fn); + unsigned long offset, status, cfg_base, flags, entryLo0, entryLo1, r; + int error = PCIBIOS_SUCCESSFUL; + + if (device > 19) { + *data = 0xffffffff; + return -1; + } + + local_irq_save(flags); + r = __raw_readl(ctx->regs + PCI_REG_STATCMD) & 0x0000ffff; + r |= PCI_STATCMD_STATUS(0x2000); + __raw_writel(r, ctx->regs + PCI_REG_STATCMD); + wmb(); + + /* Allow board vendors to implement their own off-chip IDSEL. + * If it doesn't succeed, may as well bail out at this point. + */ + if (ctx->board_pci_idsel(device, 1) == 0) { + *data = 0xffffffff; + local_irq_restore(flags); + return -1; + } + + /* Setup the config window */ + if (bus->number == 0) + cfg_base = (1 << device) << 11; + else + cfg_base = 0x80000000 | (bus->number << 16) | (device << 11); + + /* Setup the lower bits of the 36-bit address */ + offset = (function << 8) | (where & ~0x3); + /* Pick up any address that falls below the page mask */ + offset |= cfg_base & ~PAGE_MASK; + + /* Page boundary */ + cfg_base = cfg_base & PAGE_MASK; + + /* To improve performance, if the current device is the same as + * the last device accessed, we don't touch the TLB. + */ + entryLo0 = (6 << 26) | (cfg_base >> 6) | (2 << 3) | 7; + entryLo1 = (6 << 26) | (cfg_base >> 6) | (0x1000 >> 6) | (2 << 3) | 7; + if ((entryLo0 != ctx->last_elo0) || (entryLo1 != ctx->last_elo1)) { + mod_wired_entry(ctx->wired_entry, entryLo0, entryLo1, + (unsigned long)ctx->pci_cfg_vm->addr, PM_4K); + ctx->last_elo0 = entryLo0; + ctx->last_elo1 = entryLo1; + } + + if (access_type == PCI_ACCESS_WRITE) + __raw_writel(*data, ctx->pci_cfg_vm->addr + offset); + else + *data = __raw_readl(ctx->pci_cfg_vm->addr + offset); + wmb(); + + DBG("alchemy-pci: cfg access %d bus %u dev %u at %x dat %x conf %lx\n", + access_type, bus->number, device, where, *data, offset); + + /* check for errors, master abort */ + status = __raw_readl(ctx->regs + PCI_REG_STATCMD); + if (status & (1 << 29)) { + *data = 0xffffffff; + error = -1; + DBG("alchemy-pci: master abort on cfg access %d bus %d dev %d\n", + access_type, bus->number, device); + } else if ((status >> 28) & 0xf) { + DBG("alchemy-pci: PCI ERR detected: dev %d, status %lx\n", + device, (status >> 28) & 0xf); + + /* clear errors */ + __raw_writel(status & 0xf000ffff, ctx->regs + PCI_REG_STATCMD); + + *data = 0xffffffff; + error = -1; + } + + /* Take away the IDSEL. */ + (void)ctx->board_pci_idsel(device, 0); + + local_irq_restore(flags); + return error; +} + +static int read_config_byte(struct pci_bus *bus, unsigned int devfn, + int where, u8 *val) +{ + u32 data; + int ret = config_access(PCI_ACCESS_READ, bus, devfn, where, &data); + + if (where & 1) + data >>= 8; + if (where & 2) + data >>= 16; + *val = data & 0xff; + return ret; +} + +static int read_config_word(struct pci_bus *bus, unsigned int devfn, + int where, u16 *val) +{ + u32 data; + int ret = config_access(PCI_ACCESS_READ, bus, devfn, where, &data); + + if (where & 2) + data >>= 16; + *val = data & 0xffff; + return ret; +} + +static int read_config_dword(struct pci_bus *bus, unsigned int devfn, + int where, u32 *val) +{ + return config_access(PCI_ACCESS_READ, bus, devfn, where, val); +} + +static int write_config_byte(struct pci_bus *bus, unsigned int devfn, + int where, u8 val) +{ + u32 data = 0; + + if (config_access(PCI_ACCESS_READ, bus, devfn, where, &data)) + return -1; + + data = (data & ~(0xff << ((where & 3) << 3))) | + (val << ((where & 3) << 3)); + + if (config_access(PCI_ACCESS_WRITE, bus, devfn, where, &data)) + return -1; + + return PCIBIOS_SUCCESSFUL; +} + +static int write_config_word(struct pci_bus *bus, unsigned int devfn, + int where, u16 val) +{ + u32 data = 0; + + if (config_access(PCI_ACCESS_READ, bus, devfn, where, &data)) + return -1; + + data = (data & ~(0xffff << ((where & 3) << 3))) | + (val << ((where & 3) << 3)); + + if (config_access(PCI_ACCESS_WRITE, bus, devfn, where, &data)) + return -1; + + return PCIBIOS_SUCCESSFUL; +} + +static int write_config_dword(struct pci_bus *bus, unsigned int devfn, + int where, u32 val) +{ + return config_access(PCI_ACCESS_WRITE, bus, devfn, where, &val); +} + +static int alchemy_pci_read(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 *val) +{ + switch (size) { + case 1: { + u8 _val; + int rc = read_config_byte(bus, devfn, where, &_val); + + *val = _val; + return rc; + } + case 2: { + u16 _val; + int rc = read_config_word(bus, devfn, where, &_val); + + *val = _val; + return rc; + } + default: + return read_config_dword(bus, devfn, where, val); + } +} + +static int alchemy_pci_write(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 val) +{ + switch (size) { + case 1: + return write_config_byte(bus, devfn, where, (u8) val); + case 2: + return write_config_word(bus, devfn, where, (u16) val); + default: + return write_config_dword(bus, devfn, where, val); + } +} + +static struct pci_ops alchemy_pci_ops = { + .read = alchemy_pci_read, + .write = alchemy_pci_write, +}; + +static int alchemy_pci_def_idsel(unsigned int devsel, int assert) +{ + return 1; /* success */ +} + +/* save PCI controller register contents. */ +static int alchemy_pci_suspend(void) +{ + struct alchemy_pci_context *ctx = __alchemy_pci_ctx; + if (!ctx) + return 0; + + ctx->pm[0] = __raw_readl(ctx->regs + PCI_REG_CMEM); + ctx->pm[1] = __raw_readl(ctx->regs + PCI_REG_CONFIG) & 0x0009ffff; + ctx->pm[2] = __raw_readl(ctx->regs + PCI_REG_B2BMASK_CCH); + ctx->pm[3] = __raw_readl(ctx->regs + PCI_REG_B2BBASE0_VID); + ctx->pm[4] = __raw_readl(ctx->regs + PCI_REG_B2BBASE1_SID); + ctx->pm[5] = __raw_readl(ctx->regs + PCI_REG_MWMASK_DEV); + ctx->pm[6] = __raw_readl(ctx->regs + PCI_REG_MWBASE_REV_CCL); + ctx->pm[7] = __raw_readl(ctx->regs + PCI_REG_ID); + ctx->pm[8] = __raw_readl(ctx->regs + PCI_REG_CLASSREV); + ctx->pm[9] = __raw_readl(ctx->regs + PCI_REG_PARAM); + ctx->pm[10] = __raw_readl(ctx->regs + PCI_REG_MBAR); + ctx->pm[11] = __raw_readl(ctx->regs + PCI_REG_TIMEOUT); + + return 0; +} + +static void alchemy_pci_resume(void) +{ + struct alchemy_pci_context *ctx = __alchemy_pci_ctx; + if (!ctx) + return; + + __raw_writel(ctx->pm[0], ctx->regs + PCI_REG_CMEM); + __raw_writel(ctx->pm[2], ctx->regs + PCI_REG_B2BMASK_CCH); + __raw_writel(ctx->pm[3], ctx->regs + PCI_REG_B2BBASE0_VID); + __raw_writel(ctx->pm[4], ctx->regs + PCI_REG_B2BBASE1_SID); + __raw_writel(ctx->pm[5], ctx->regs + PCI_REG_MWMASK_DEV); + __raw_writel(ctx->pm[6], ctx->regs + PCI_REG_MWBASE_REV_CCL); + __raw_writel(ctx->pm[7], ctx->regs + PCI_REG_ID); + __raw_writel(ctx->pm[8], ctx->regs + PCI_REG_CLASSREV); + __raw_writel(ctx->pm[9], ctx->regs + PCI_REG_PARAM); + __raw_writel(ctx->pm[10], ctx->regs + PCI_REG_MBAR); + __raw_writel(ctx->pm[11], ctx->regs + PCI_REG_TIMEOUT); + wmb(); + __raw_writel(ctx->pm[1], ctx->regs + PCI_REG_CONFIG); + wmb(); + + /* YAMON on all db1xxx boards wipes the TLB and writes zero to C0_wired + * on resume, making it necessary to recreate it as soon as possible. + */ + ctx->wired_entry = 8191; /* impossibly high value */ + alchemy_pci_wired_entry(ctx); /* install it */ +} + +static struct syscore_ops alchemy_pci_pmops = { + .suspend = alchemy_pci_suspend, + .resume = alchemy_pci_resume, +}; + +static int alchemy_pci_probe(struct platform_device *pdev) +{ + struct alchemy_pci_platdata *pd = pdev->dev.platform_data; + struct alchemy_pci_context *ctx; + void __iomem *virt_io; + unsigned long val; + struct resource *r; + struct clk *c; + int ret; + + /* need at least PCI IRQ mapping table */ + if (!pd) { + dev_err(&pdev->dev, "need platform data for PCI setup\n"); + ret = -ENODEV; + goto out; + } + + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); + if (!ctx) { + dev_err(&pdev->dev, "no memory for pcictl context\n"); + ret = -ENOMEM; + goto out; + } + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!r) { + dev_err(&pdev->dev, "no pcictl ctrl regs resource\n"); + ret = -ENODEV; + goto out1; + } + + if (!request_mem_region(r->start, resource_size(r), pdev->name)) { + dev_err(&pdev->dev, "cannot claim pci regs\n"); + ret = -ENODEV; + goto out1; + } + + c = clk_get(&pdev->dev, "pci_clko"); + if (IS_ERR(c)) { + dev_err(&pdev->dev, "unable to find PCI clock\n"); + ret = PTR_ERR(c); + goto out2; + } + + ret = clk_prepare_enable(c); + if (ret) { + dev_err(&pdev->dev, "cannot enable PCI clock\n"); + goto out6; + } + + ctx->regs = ioremap(r->start, resource_size(r)); + if (!ctx->regs) { + dev_err(&pdev->dev, "cannot map pci regs\n"); + ret = -ENODEV; + goto out5; + } + + /* map parts of the PCI IO area */ + /* REVISIT: if this changes with a newer variant (doubt it) make this + * a platform resource. + */ + virt_io = ioremap(AU1500_PCI_IO_PHYS_ADDR, 0x00100000); + if (!virt_io) { + dev_err(&pdev->dev, "cannot remap pci io space\n"); + ret = -ENODEV; + goto out3; + } + ctx->alchemy_pci_ctrl.io_map_base = (unsigned long)virt_io; + + /* Au1500 revisions older than AD have borked coherent PCI */ + if (alchemy_get_cputype() == ALCHEMY_CPU_AU1500 && + read_c0_prid() < 0x01030202 && !dma_default_coherent) { + val = __raw_readl(ctx->regs + PCI_REG_CONFIG); + val |= PCI_CONFIG_NC; + __raw_writel(val, ctx->regs + PCI_REG_CONFIG); + wmb(); + dev_info(&pdev->dev, "non-coherent PCI on Au1500 AA/AB/AC\n"); + } + + if (pd->board_map_irq) + ctx->board_map_irq = pd->board_map_irq; + + if (pd->board_pci_idsel) + ctx->board_pci_idsel = pd->board_pci_idsel; + else + ctx->board_pci_idsel = alchemy_pci_def_idsel; + + /* fill in relevant pci_controller members */ + ctx->alchemy_pci_ctrl.pci_ops = &alchemy_pci_ops; + ctx->alchemy_pci_ctrl.mem_resource = &alchemy_pci_def_memres; + ctx->alchemy_pci_ctrl.io_resource = &alchemy_pci_def_iores; + + /* we can't ioremap the entire pci config space because it's too large, + * nor can we dynamically ioremap it because some drivers use the + * PCI config routines from within atomic contex and that becomes a + * problem in get_vm_area(). Instead we use one wired TLB entry to + * handle all config accesses for all busses. + */ + ctx->pci_cfg_vm = get_vm_area(0x2000, VM_IOREMAP); + if (!ctx->pci_cfg_vm) { + dev_err(&pdev->dev, "unable to get vm area\n"); + ret = -ENOMEM; + goto out4; + } + ctx->wired_entry = 8191; /* impossibly high value */ + alchemy_pci_wired_entry(ctx); /* install it */ + + set_io_port_base((unsigned long)ctx->alchemy_pci_ctrl.io_map_base); + + /* board may want to modify bits in the config register, do it now */ + val = __raw_readl(ctx->regs + PCI_REG_CONFIG); + val &= ~pd->pci_cfg_clr; + val |= pd->pci_cfg_set; + val &= ~PCI_CONFIG_PD; /* clear disable bit */ + __raw_writel(val, ctx->regs + PCI_REG_CONFIG); + wmb(); + + __alchemy_pci_ctx = ctx; + platform_set_drvdata(pdev, ctx); + register_syscore_ops(&alchemy_pci_pmops); + register_pci_controller(&ctx->alchemy_pci_ctrl); + + dev_info(&pdev->dev, "PCI controller at %ld MHz\n", + clk_get_rate(c) / 1000000); + + return 0; + +out4: + iounmap(virt_io); +out3: + iounmap(ctx->regs); +out5: + clk_disable_unprepare(c); +out6: + clk_put(c); +out2: + release_mem_region(r->start, resource_size(r)); +out1: + kfree(ctx); +out: + return ret; +} + +static struct platform_driver alchemy_pcictl_driver = { + .probe = alchemy_pci_probe, + .driver = { + .name = "alchemy-pci", + }, +}; + +static int __init alchemy_pci_init(void) +{ + /* Au1500/Au1550 have PCI */ + switch (alchemy_get_cputype()) { + case ALCHEMY_CPU_AU1500: + case ALCHEMY_CPU_AU1550: + return platform_driver_register(&alchemy_pcictl_driver); + } + return 0; +} +arch_initcall(alchemy_pci_init); + + +int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) +{ + struct alchemy_pci_context *ctx = dev->sysdata; + if (ctx && ctx->board_map_irq) + return ctx->board_map_irq(dev, slot, pin); + return -1; +} + +int pcibios_plat_dev_init(struct pci_dev *dev) +{ + return 0; +} |