MIPS: Alchemy: Redo PCI as platform driver

- Rewrite Alchemy PCI support as a platform driver.
- Fixup boards which have PCI.

Run-tested on DB1500 and DB1550.

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
To: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/2706/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

 delete mode 100644 arch/mips/alchemy/common/pci.c
 delete mode 100644 arch/mips/pci/fixup-au1000.c
 delete mode 100644 arch/mips/pci/ops-au1000.c
 create mode 100644 arch/mips/pci/pci-alchemy.c

1 files changed, 516 insertions, 0 deletions

diff --git a/arch/mips/pci/pci-alchemy.c b/arch/mips/pci/pci-alchemy.c
new file mode 100644
index 000000000000..4ee57104e47b
--- /dev/null
+++ b/arch/mips/pci/pci-alchemy.c
@@ -0,0 +1,516 @@
+/*
+ * 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/types.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/vmalloc.h>
+
+#include <asm/mach-au1x00/au1000.h>
+
+#ifdef CONFIG_DEBUG_PCI
+#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);
+};
+
+/* 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() & 0xff;
+	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;
+	}
+
+	/* YAMON on all db1xxx boards wipes the TLB and writes zero to C0_wired
+	 * on resume, clearing our wired entry.  Unfortunately the ->resume()
+	 * callback is called way way way too late (and ->suspend() too early)
+	 * to have them destroy and recreate it.  Instead just test if c0_wired
+	 * is now lower than the index we retrieved before suspending and then
+	 * recreate the entry if necessary.  Of course this is totally bonkers
+	 * and breaks as soon as someone else adds another wired entry somewhere
+	 * else.  Anyone have any ideas how to handle this better?
+	 */
+	if (unlikely(read_c0_wired() < ctx->wired_entry))
+		alchemy_pci_wired_entry(ctx);
+
+	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",
+		    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 */
+}
+
+static int __devinit 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;
+	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;
+	}
+
+	ctx->regs = ioremap_nocache(r->start, resource_size(r));
+	if (!ctx->regs) {
+		dev_err(&pdev->dev, "cannot map pci regs\n");
+		ret = -ENODEV;
+		goto out2;
+	}
+
+	/* 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;
+
+#ifdef CONFIG_DMA_NONCOHERENT
+	/* Au1500 revisions older than AD have borked coherent PCI */
+	if ((alchemy_get_cputype() == ALCHEMY_CPU_AU1500) &&
+	    (read_c0_prid() < 0x01030202)) {
+		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");
+	}
+#endif
+
+	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 = 8192;	/* impossibly high value */
+
+	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();
+
+	platform_set_drvdata(pdev, ctx);
+	register_pci_controller(&ctx->alchemy_pci_ctrl);
+
+	return 0;
+
+out4:
+	iounmap(virt_io);
+out3:
+	iounmap(ctx->regs);
+out2:
+	release_mem_region(r->start, resource_size(r));
+out1:
+	kfree(ctx);
+out:
+	return ret;
+}
+
+
+#ifdef CONFIG_PM
+/* save PCI controller register contents. */
+static int alchemy_pci_suspend(struct device *dev)
+{
+	struct alchemy_pci_context *ctx = dev_get_drvdata(dev);
+
+	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 int alchemy_pci_resume(struct device *dev)
+{
+	struct alchemy_pci_context *ctx = dev_get_drvdata(dev);
+
+	__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();
+
+	return 0;
+}
+
+static const struct dev_pm_ops alchemy_pci_pmops = {
+	.suspend	= alchemy_pci_suspend,
+	.resume		= alchemy_pci_resume,
+};
+
+#define ALCHEMY_PCICTL_PM	(&alchemy_pci_pmops)
+
+#else
+#define ALCHEMY_PCICTL_PM	NULL
+#endif
+
+static struct platform_driver alchemy_pcictl_driver = {
+	.probe		= alchemy_pci_probe,
+	.driver	= {
+		.name	= "alchemy-pci",
+		.owner	= THIS_MODULE,
+		.pm	= ALCHEMY_PCICTL_PM,
+	},
+};
+
+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 __init 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;
+}