bcma: add Broadcom specific AMBA bus driver

Broadcom has released cards based on a new AMBA-based bus type. From a
programming point of view, this new bus type differs from AMBA and does
not use AMBA common registers. It also differs enough from SSB. We
decided that a new bus driver is needed to keep the code clean.

In its current form, the driver detects devices present on the bus and
registers them in the system. It allows registering BCMA drivers for
specified bus devices and provides them basic operations. The bus driver
itself includes two important bus managing drivers: ChipCommon core
driver and PCI(c) core driver. They are early used to allow correct
initialization.

Currently code is limited to supporting buses on PCI(e) devices, however
the driver is designed to be used also on other hosts. The host
abstraction layer is implemented and already used for PCI(e).

Support for PCI(e) hosts is working and seems to be stable (access to
80211 core was tested successfully on a few devices). We can still
optimize it by using some fixed windows, but this can be done later
without affecting any external code. Windows are just ranges in MMIO
used for accessing cores on the bus.

Cc: Greg KH <greg@kroah.com>
Cc: Michael Büsch <mb@bu3sch.de>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: George Kashperko <george@znau.edu.ua>
Cc: Arend van Spriel <arend@broadcom.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Botting <andy@andybotting.com>
Cc: linuxdriverproject <devel@linuxdriverproject.org>
Cc: linux-kernel@vger.kernel.org <linux-kernel@vger.kernel.org>
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 247 insertions, 0 deletions

diff --git a/drivers/bcma/main.c b/drivers/bcma/main.c
new file mode 100644
index 0000000..be52344
--- /dev/null
+++ b/drivers/bcma/main.c
@@ -0,0 +1,247 @@
+/*
+ * Broadcom specific AMBA
+ * Bus subsystem
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include "bcma_private.h"
+#include <linux/bcma/bcma.h>
+
+MODULE_DESCRIPTION("Broadcom's specific AMBA driver");
+MODULE_LICENSE("GPL");
+
+static int bcma_bus_match(struct device *dev, struct device_driver *drv);
+static int bcma_device_probe(struct device *dev);
+static int bcma_device_remove(struct device *dev);
+
+static ssize_t manuf_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
+	return sprintf(buf, "0x%03X\n", core->id.manuf);
+}
+static ssize_t id_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
+	return sprintf(buf, "0x%03X\n", core->id.id);
+}
+static ssize_t rev_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
+	return sprintf(buf, "0x%02X\n", core->id.rev);
+}
+static ssize_t class_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
+	return sprintf(buf, "0x%X\n", core->id.class);
+}
+static struct device_attribute bcma_device_attrs[] = {
+	__ATTR_RO(manuf),
+	__ATTR_RO(id),
+	__ATTR_RO(rev),
+	__ATTR_RO(class),
+	__ATTR_NULL,
+};
+
+static struct bus_type bcma_bus_type = {
+	.name		= "bcma",
+	.match		= bcma_bus_match,
+	.probe		= bcma_device_probe,
+	.remove		= bcma_device_remove,
+	.dev_attrs	= bcma_device_attrs,
+};
+
+static struct bcma_device *bcma_find_core(struct bcma_bus *bus, u16 coreid)
+{
+	struct bcma_device *core;
+
+	list_for_each_entry(core, &bus->cores, list) {
+		if (core->id.id == coreid)
+			return core;
+	}
+	return NULL;
+}
+
+static void bcma_release_core_dev(struct device *dev)
+{
+	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
+	kfree(core);
+}
+
+static int bcma_register_cores(struct bcma_bus *bus)
+{
+	struct bcma_device *core;
+	int err, dev_id = 0;
+
+	list_for_each_entry(core, &bus->cores, list) {
+		/* We support that cores ourself */
+		switch (core->id.id) {
+		case BCMA_CORE_CHIPCOMMON:
+		case BCMA_CORE_PCI:
+		case BCMA_CORE_PCIE:
+			continue;
+		}
+
+		core->dev.release = bcma_release_core_dev;
+		core->dev.bus = &bcma_bus_type;
+		dev_set_name(&core->dev, "bcma%d:%d", 0/*bus->num*/, dev_id);
+
+		switch (bus->hosttype) {
+		case BCMA_HOSTTYPE_PCI:
+			core->dev.parent = &bus->host_pci->dev;
+			break;
+		case BCMA_HOSTTYPE_NONE:
+		case BCMA_HOSTTYPE_SDIO:
+			break;
+		}
+
+		err = device_register(&core->dev);
+		if (err) {
+			pr_err("Could not register dev for core 0x%03X\n",
+			       core->id.id);
+			continue;
+		}
+		core->dev_registered = true;
+		dev_id++;
+	}
+
+	return 0;
+}
+
+static void bcma_unregister_cores(struct bcma_bus *bus)
+{
+	struct bcma_device *core;
+
+	list_for_each_entry(core, &bus->cores, list) {
+		if (core->dev_registered)
+			device_unregister(&core->dev);
+	}
+}
+
+int bcma_bus_register(struct bcma_bus *bus)
+{
+	int err;
+	struct bcma_device *core;
+
+	/* Scan for devices (cores) */
+	err = bcma_bus_scan(bus);
+	if (err) {
+		pr_err("Failed to scan: %d\n", err);
+		return -1;
+	}
+
+	/* Init CC core */
+	core = bcma_find_core(bus, BCMA_CORE_CHIPCOMMON);
+	if (core) {
+		bus->drv_cc.core = core;
+		bcma_core_chipcommon_init(&bus->drv_cc);
+	}
+
+	/* Init PCIE core */
+	core = bcma_find_core(bus, BCMA_CORE_PCIE);
+	if (core) {
+		bus->drv_pci.core = core;
+		bcma_core_pci_init(&bus->drv_pci);
+	}
+
+	/* Register found cores */
+	bcma_register_cores(bus);
+
+	pr_info("Bus registered\n");
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(bcma_bus_register);
+
+void bcma_bus_unregister(struct bcma_bus *bus)
+{
+	bcma_unregister_cores(bus);
+}
+EXPORT_SYMBOL_GPL(bcma_bus_unregister);
+
+int __bcma_driver_register(struct bcma_driver *drv, struct module *owner)
+{
+	drv->drv.name = drv->name;
+	drv->drv.bus = &bcma_bus_type;
+	drv->drv.owner = owner;
+
+	return driver_register(&drv->drv);
+}
+EXPORT_SYMBOL_GPL(__bcma_driver_register);
+
+void bcma_driver_unregister(struct bcma_driver *drv)
+{
+	driver_unregister(&drv->drv);
+}
+EXPORT_SYMBOL_GPL(bcma_driver_unregister);
+
+static int bcma_bus_match(struct device *dev, struct device_driver *drv)
+{
+	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
+	struct bcma_driver *adrv = container_of(drv, struct bcma_driver, drv);
+	const struct bcma_device_id *cid = &core->id;
+	const struct bcma_device_id *did;
+
+	for (did = adrv->id_table; did->manuf || did->id || did->rev; did++) {
+	    if ((did->manuf == cid->manuf || did->manuf == BCMA_ANY_MANUF) &&
+		(did->id == cid->id || did->id == BCMA_ANY_ID) &&
+		(did->rev == cid->rev || did->rev == BCMA_ANY_REV) &&
+		(did->class == cid->class || did->class == BCMA_ANY_CLASS))
+			return 1;
+	}
+	return 0;
+}
+
+static int bcma_device_probe(struct device *dev)
+{
+	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
+	struct bcma_driver *adrv = container_of(dev->driver, struct bcma_driver,
+					       drv);
+	int err = 0;
+
+	if (adrv->probe)
+		err = adrv->probe(core);
+
+	return err;
+}
+
+static int bcma_device_remove(struct device *dev)
+{
+	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
+	struct bcma_driver *adrv = container_of(dev->driver, struct bcma_driver,
+					       drv);
+
+	if (adrv->remove)
+		adrv->remove(core);
+
+	return 0;
+}
+
+static int __init bcma_modinit(void)
+{
+	int err;
+
+	err = bus_register(&bcma_bus_type);
+	if (err)
+		return err;
+
+#ifdef CONFIG_BCMA_HOST_PCI
+	err = bcma_host_pci_init();
+	if (err) {
+		pr_err("PCI host initialization failed\n");
+		err = 0;
+	}
+#endif
+
+	return err;
+}
+fs_initcall(bcma_modinit);
+
+static void __exit bcma_modexit(void)
+{
+#ifdef CONFIG_BCMA_HOST_PCI
+	bcma_host_pci_exit();
+#endif
+	bus_unregister(&bcma_bus_type);
+}
+module_exit(bcma_modexit)