MIPS: GIO bus support for SGI IP22/28

SGI IP22/IP28 machines have GIO busses for adding graphics and other
extension cards. This patch adds support for GIO driver/device
handling and converts the newport console driver to a GIO driver.

[ralf@linux-mips.org: Fixed build error caused by the modules.h -> export.h
changes.]

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
To: linux-fbdev@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/2886/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 428 insertions, 0 deletions

diff --git a/arch/mips/sgi-ip22/ip22-gio.c b/arch/mips/sgi-ip22/ip22-gio.c
new file mode 100644
index 000000000000..f5ebc092aed5
--- /dev/null
+++ b/arch/mips/sgi-ip22/ip22-gio.c
@@ -0,0 +1,428 @@
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+
+#include <asm/addrspace.h>
+#include <asm/paccess.h>
+#include <asm/gio_device.h>
+#include <asm/sgi/gio.h>
+#include <asm/sgi/hpc3.h>
+#include <asm/sgi/mc.h>
+#include <asm/sgi/ip22.h>
+
+static struct bus_type gio_bus_type;
+
+static struct {
+	const char *name;
+	__u8       id;
+} gio_name_table[] = {
+	{ .name = "SGI Impact", .id = 0x10 },
+	{ .name = "Phobos G160", .id = 0x35 },
+	/* fake IDs */
+	{ .name = "SGI Newport", .id = 0x7e },
+	{ .name = "SGI GR2/GR3", .id = 0x7f },
+};
+
+static struct device gio_bus = {
+	.init_name = "gio",
+};
+
+/**
+ * gio_match_device - Tell if an of_device structure has a matching
+ * gio_match structure
+ * @ids: array of of device match structures to search in
+ * @dev: the of device structure to match against
+ *
+ * Used by a driver to check whether an of_device present in the
+ * system is in its list of supported devices.
+ */
+const struct gio_device_id *gio_match_device(const struct gio_device_id *match,
+		     const struct gio_device *dev)
+{
+	const struct gio_device_id *ids;
+
+	for (ids = match; ids->id != 0xff; ids++)
+		if (ids->id == dev->id.id)
+			return ids;
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(gio_match_device);
+
+struct gio_device *gio_dev_get(struct gio_device *dev)
+{
+	struct device *tmp;
+
+	if (!dev)
+		return NULL;
+	tmp = get_device(&dev->dev);
+	if (tmp)
+		return to_gio_device(tmp);
+	else
+		return NULL;
+}
+EXPORT_SYMBOL_GPL(gio_dev_get);
+
+void gio_dev_put(struct gio_device *dev)
+{
+	if (dev)
+		put_device(&dev->dev);
+}
+EXPORT_SYMBOL_GPL(gio_dev_put);
+
+/**
+ * gio_release_dev - free an gio device structure when all users of it are finished.
+ * @dev: device that's been disconnected
+ *
+ * Will be called only by the device core when all users of this gio device are
+ * done.
+ */
+void gio_release_dev(struct device *dev)
+{
+	struct gio_device *giodev;
+
+	giodev = to_gio_device(dev);
+	kfree(giodev);
+}
+EXPORT_SYMBOL_GPL(gio_release_dev);
+
+int gio_device_register(struct gio_device *giodev)
+{
+	giodev->dev.bus = &gio_bus_type;
+	giodev->dev.parent = &gio_bus;
+	return device_register(&giodev->dev);
+}
+EXPORT_SYMBOL_GPL(gio_device_register);
+
+void gio_device_unregister(struct gio_device *giodev)
+{
+	device_unregister(&giodev->dev);
+}
+EXPORT_SYMBOL_GPL(gio_device_unregister);
+
+static int gio_bus_match(struct device *dev, struct device_driver *drv)
+{
+	struct gio_device *gio_dev = to_gio_device(dev);
+	struct gio_driver *gio_drv = to_gio_driver(drv);
+
+	return gio_match_device(gio_drv->id_table, gio_dev) != NULL;
+}
+
+static int gio_device_probe(struct device *dev)
+{
+	int error = -ENODEV;
+	struct gio_driver *drv;
+	struct gio_device *gio_dev;
+	const struct gio_device_id *match;
+
+	drv = to_gio_driver(dev->driver);
+	gio_dev = to_gio_device(dev);
+
+	if (!drv->probe)
+		return error;
+
+	gio_dev_get(gio_dev);
+
+	match = gio_match_device(drv->id_table, gio_dev);
+	if (match)
+		error = drv->probe(gio_dev, match);
+	if (error)
+		gio_dev_put(gio_dev);
+
+	return error;
+}
+
+static int gio_device_remove(struct device *dev)
+{
+	struct gio_device *gio_dev = to_gio_device(dev);
+	struct gio_driver *drv = to_gio_driver(dev->driver);
+
+	if (dev->driver && drv->remove)
+		drv->remove(gio_dev);
+	return 0;
+}
+
+static int gio_device_suspend(struct device *dev, pm_message_t state)
+{
+	struct gio_device *gio_dev = to_gio_device(dev);
+	struct gio_driver *drv = to_gio_driver(dev->driver);
+	int error = 0;
+
+	if (dev->driver && drv->suspend)
+		error = drv->suspend(gio_dev, state);
+	return error;
+}
+
+static int gio_device_resume(struct device *dev)
+{
+	struct gio_device *gio_dev = to_gio_device(dev);
+	struct gio_driver *drv = to_gio_driver(dev->driver);
+	int error = 0;
+
+	if (dev->driver && drv->resume)
+		error = drv->resume(gio_dev);
+	return error;
+}
+
+static void gio_device_shutdown(struct device *dev)
+{
+	struct gio_device *gio_dev = to_gio_device(dev);
+	struct gio_driver *drv = to_gio_driver(dev->driver);
+
+	if (dev->driver && drv->shutdown)
+		drv->shutdown(gio_dev);
+}
+
+static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct gio_device *gio_dev = to_gio_device(dev);
+	int len = snprintf(buf, PAGE_SIZE, "gio:%x\n", gio_dev->id.id);
+
+	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
+}
+
+static ssize_t name_show(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	struct gio_device *giodev;
+
+	giodev = to_gio_device(dev);
+	return sprintf(buf, "%s", giodev->name);
+}
+
+static ssize_t id_show(struct device *dev,
+		       struct device_attribute *attr, char *buf)
+{
+	struct gio_device *giodev;
+
+	giodev = to_gio_device(dev);
+	return sprintf(buf, "%x", giodev->id.id);
+}
+
+static struct device_attribute gio_dev_attrs[] = {
+	__ATTR_RO(modalias),
+	__ATTR_RO(name),
+	__ATTR_RO(id),
+	__ATTR_NULL,
+};
+
+static int gio_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct gio_device *gio_dev = to_gio_device(dev);
+
+	add_uevent_var(env, "MODALIAS=gio:%x", gio_dev->id.id);
+	return 0;
+}
+
+int gio_register_driver(struct gio_driver *drv)
+{
+	/* initialize common driver fields */
+	if (!drv->driver.name)
+		drv->driver.name = drv->name;
+	if (!drv->driver.owner)
+		drv->driver.owner = drv->owner;
+	drv->driver.bus = &gio_bus_type;
+
+	/* register with core */
+	return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(gio_register_driver);
+
+void gio_unregister_driver(struct gio_driver *drv)
+{
+	driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(gio_unregister_driver);
+
+void gio_set_master(struct gio_device *dev)
+{
+	u32 tmp = sgimc->giopar;
+
+	switch (dev->slotno) {
+	case 0:
+		tmp |= SGIMC_GIOPAR_MASTERGFX;
+		break;
+	case 1:
+		tmp |= SGIMC_GIOPAR_MASTEREXP0;
+		break;
+	case 2:
+		tmp |= SGIMC_GIOPAR_MASTEREXP1;
+		break;
+	}
+	sgimc->giopar = tmp;
+}
+EXPORT_SYMBOL_GPL(gio_set_master);
+
+void ip22_gio_set_64bit(int slotno)
+{
+	u32 tmp = sgimc->giopar;
+
+	switch (slotno) {
+	case 0:
+		tmp |= SGIMC_GIOPAR_GFX64;
+		break;
+	case 1:
+		tmp |= SGIMC_GIOPAR_EXP064;
+		break;
+	case 2:
+		tmp |= SGIMC_GIOPAR_EXP164;
+		break;
+	}
+	sgimc->giopar = tmp;
+}
+
+static int ip22_gio_id(unsigned long addr, u32 *res)
+{
+	u8 tmp8;
+	u8 tmp16;
+	u32 tmp32;
+	u8 *ptr8;
+	u16 *ptr16;
+	u32 *ptr32;
+
+	ptr32 = (void *)CKSEG1ADDR(addr);
+	if (!get_dbe(tmp32, ptr32)) {
+		/*
+		 * We got no DBE, but this doesn't mean anything.
+		 * If GIO is pipelined (which can't be disabled
+		 * for GFX slot) we don't get a DBE, but we see
+		 * the transfer size as data. So we do an 8bit
+		 * and a 16bit access and check whether the common
+		 * data matches
+		 */
+		ptr8 = (void *)CKSEG1ADDR(addr + 3);
+		get_dbe(tmp8, ptr8);
+		ptr16 = (void *)CKSEG1ADDR(addr + 2);
+		get_dbe(tmp16, ptr16);
+		if (tmp8 == (tmp16 & 0xff) &&
+		    tmp8 == (tmp32 & 0xff) &&
+		    tmp16 == (tmp32 & 0xffff)) {
+			*res = tmp32;
+			return 1;
+		}
+	}
+	return 0; /* nothing here */
+}
+
+#define HQ2_MYSTERY_OFFS       0x6A07C
+#define NEWPORT_USTATUS_OFFS   0xF133C
+
+static int ip22_is_gr2(unsigned long addr)
+{
+	u32 tmp;
+	u32 *ptr;
+
+	/* HQ2 only allows 32bit accesses */
+	ptr = (void *)CKSEG1ADDR(addr + HQ2_MYSTERY_OFFS);
+	if (!get_dbe(tmp, ptr)) {
+		if (tmp == 0xdeadbeef)
+			return 1;
+	}
+	return 0;
+}
+
+
+static void ip22_check_gio(int slotno, unsigned long addr)
+{
+	const char *name = "Unknown";
+	struct gio_device *gio_dev;
+	u32 tmp;
+	__u8 id;
+	int i;
+
+	/* first look for GR2/GR3 by checking mystery register */
+	if (ip22_is_gr2(addr))
+		tmp = 0x7f;
+	else {
+		if (!ip22_gio_id(addr, &tmp)) {
+			/*
+			 * no GIO signature at start address of slot, but
+			 * Newport doesn't have one, so let's check usea
+			 * status register
+			 */
+			if (ip22_gio_id(addr + NEWPORT_USTATUS_OFFS, &tmp))
+				tmp = 0x7e;
+			else
+				tmp = 0;
+		}
+	}
+	if (tmp) {
+		id = GIO_ID(tmp);
+		if (tmp & GIO_32BIT_ID) {
+			if (tmp & GIO_64BIT_IFACE)
+				ip22_gio_set_64bit(slotno);
+		}
+		for (i = 0; i < ARRAY_SIZE(gio_name_table); i++) {
+			if (id == gio_name_table[i].id) {
+				name = gio_name_table[i].name;
+				break;
+			}
+		}
+		printk(KERN_INFO "GIO: slot %d : %s (id %x)\n",
+		       slotno, name, id);
+		gio_dev = kzalloc(sizeof *gio_dev, GFP_KERNEL);
+		gio_dev->name = name;
+		gio_dev->slotno = slotno;
+		gio_dev->id.id = id;
+		gio_dev->resource.start = addr;
+		gio_dev->resource.end = addr + 0x3fffff;
+		gio_dev->resource.flags = IORESOURCE_MEM;
+		dev_set_name(&gio_dev->dev, "%d", slotno);
+		gio_device_register(gio_dev);
+	} else
+		printk(KERN_INFO "GIO: slot %d : Empty\n", slotno);
+}
+
+static struct bus_type gio_bus_type = {
+	.name      = "gio",
+	.dev_attrs = gio_dev_attrs,
+	.match     = gio_bus_match,
+	.probe     = gio_device_probe,
+	.remove    = gio_device_remove,
+	.suspend   = gio_device_suspend,
+	.resume    = gio_device_resume,
+	.shutdown  = gio_device_shutdown,
+	.uevent    = gio_device_uevent,
+};
+
+static struct resource gio_bus_resource = {
+	.start = GIO_SLOT_GFX_BASE,
+	.end   = GIO_SLOT_GFX_BASE + 0x9fffff,
+	.name  = "GIO Bus",
+	.flags = IORESOURCE_MEM,
+};
+
+int __init ip22_gio_init(void)
+{
+	unsigned int pbdma __maybe_unused;
+	int ret;
+
+	ret = device_register(&gio_bus);
+	if (ret)
+		return ret;
+
+	ret = bus_register(&gio_bus_type);
+	if (!ret) {
+		request_resource(&iomem_resource, &gio_bus_resource);
+		printk(KERN_INFO "GIO: Probing bus...\n");
+
+		if (ip22_is_fullhouse() ||
+		    !get_dbe(pbdma, (unsigned int *)&hpc3c1->pbdma[1])) {
+			/* Indigo2 and ChallengeS */
+			ip22_check_gio(0, GIO_SLOT_GFX_BASE);
+			ip22_check_gio(1, GIO_SLOT_EXP0_BASE);
+		} else {
+			/* Indy */
+			ip22_check_gio(0, GIO_SLOT_GFX_BASE);
+			ip22_check_gio(1, GIO_SLOT_EXP0_BASE);
+			ip22_check_gio(2, GIO_SLOT_EXP1_BASE);
+		}
+	} else
+		device_unregister(&gio_bus);
+
+	return ret;
+}
+
+subsys_initcall(ip22_gio_init);