bcma: add SOC bus

This patch adds support for using bcma on a Broadcom SoC as the system
bus. An SoC like the bcm4716 could register this bus and use it to
searches for the bcma cores and register the devices on this bus.

BCMA_HOSTTYPE_NONE was intended for SoCs at first but BCMA_HOSTTYPE_SOC
is a better name.

Acked-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/bcma/Kconfig

@@ -33,6 +33,10 @@ config BCMA_DRIVER_PCI_HOSTMODE
 	help
 	  PCI core hostmode operation (external PCI bus).
 
+config BCMA_HOST_SOC
+	bool
+	depends on BCMA && MIPS
+
 config BCMA_DEBUG
 	bool "BCMA debugging"
 	depends on BCMA

drivers/bcma/Makefile

@@ -3,6 +3,7 @@ bcma-y					+= driver_chipcommon.o driver_chipcommon_pmu.o
 bcma-y					+= driver_pci.o
 bcma-$(CONFIG_BCMA_DRIVER_PCI_HOSTMODE)	+= driver_pci_host.o
 bcma-$(CONFIG_BCMA_HOST_PCI)		+= host_pci.o
+bcma-$(CONFIG_BCMA_HOST_SOC)		+= host_soc.o
 obj-$(CONFIG_BCMA)			+= bcma.o
 
 ccflags-$(CONFIG_BCMA_DEBUG)		:= -DDEBUG

drivers/bcma/core.c

@@ -110,6 +110,8 @@ EXPORT_SYMBOL_GPL(bcma_core_pll_ctl);
 u32 bcma_core_dma_translation(struct bcma_device *core)
 {
 	switch (core->bus->hosttype) {
+	case BCMA_HOSTTYPE_SOC:
+		return 0;
 	case BCMA_HOSTTYPE_PCI:
 		if (bcma_aread32(core, BCMA_IOST) & BCMA_IOST_DMA64)
 			return BCMA_DMA_TRANSLATION_DMA64_CMT;

drivers/bcma/driver_pci.c

@@ -210,7 +210,14 @@ int bcma_core_pci_irq_ctl(struct bcma_drv_pci *pc, struct bcma_device *core,
 {
 	struct pci_dev *pdev = pc->core->bus->host_pci;
 	u32 coremask, tmp;
-	int err;
+	int err = 0;
+
+	if (core->bus->hosttype != BCMA_HOSTTYPE_PCI) {
+		/* This bcma device is not on a PCI host-bus. So the IRQs are
+		 * not routed through the PCI core.
+		 * So we must not enable routing through the PCI core. */
+		goto out;
+	}
 
 	err = pci_read_config_dword(pdev, BCMA_PCI_IRQMASK, &tmp);
 	if (err)

drivers/bcma/host_soc.c

@@ -0,0 +1,183 @@
+/*
+ * Broadcom specific AMBA
+ * System on Chip (SoC) Host
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include "bcma_private.h"
+#include "scan.h"
+#include <linux/bcma/bcma.h>
+#include <linux/bcma/bcma_soc.h>
+
+static u8 bcma_host_soc_read8(struct bcma_device *core, u16 offset)
+{
+	return readb(core->io_addr + offset);
+}
+
+static u16 bcma_host_soc_read16(struct bcma_device *core, u16 offset)
+{
+	return readw(core->io_addr + offset);
+}
+
+static u32 bcma_host_soc_read32(struct bcma_device *core, u16 offset)
+{
+	return readl(core->io_addr + offset);
+}
+
+static void bcma_host_soc_write8(struct bcma_device *core, u16 offset,
+				 u8 value)
+{
+	writeb(value, core->io_addr + offset);
+}
+
+static void bcma_host_soc_write16(struct bcma_device *core, u16 offset,
+				 u16 value)
+{
+	writew(value, core->io_addr + offset);
+}
+
+static void bcma_host_soc_write32(struct bcma_device *core, u16 offset,
+				 u32 value)
+{
+	writel(value, core->io_addr + offset);
+}
+
+#ifdef CONFIG_BCMA_BLOCKIO
+static void bcma_host_soc_block_read(struct bcma_device *core, void *buffer,
+				     size_t count, u16 offset, u8 reg_width)
+{
+	void __iomem *addr = core->io_addr + offset;
+
+	switch (reg_width) {
+	case sizeof(u8): {
+		u8 *buf = buffer;
+
+		while (count) {
+			*buf = __raw_readb(addr);
+			buf++;
+			count--;
+		}
+		break;
+	}
+	case sizeof(u16): {
+		__le16 *buf = buffer;
+
+		WARN_ON(count & 1);
+		while (count) {
+			*buf = (__force __le16)__raw_readw(addr);
+			buf++;
+			count -= 2;
+		}
+		break;
+	}
+	case sizeof(u32): {
+		__le32 *buf = buffer;
+
+		WARN_ON(count & 3);
+		while (count) {
+			*buf = (__force __le32)__raw_readl(addr);
+			buf++;
+			count -= 4;
+		}
+		break;
+	}
+	default:
+		WARN_ON(1);
+	}
+}
+
+static void bcma_host_soc_block_write(struct bcma_device *core,
+				      const void *buffer,
+				      size_t count, u16 offset, u8 reg_width)
+{
+	void __iomem *addr = core->io_addr + offset;
+
+	switch (reg_width) {
+	case sizeof(u8): {
+		const u8 *buf = buffer;
+
+		while (count) {
+			__raw_writeb(*buf, addr);
+			buf++;
+			count--;
+		}
+		break;
+	}
+	case sizeof(u16): {
+		const __le16 *buf = buffer;
+
+		WARN_ON(count & 1);
+		while (count) {
+			__raw_writew((__force u16)(*buf), addr);
+			buf++;
+			count -= 2;
+		}
+		break;
+	}
+	case sizeof(u32): {
+		const __le32 *buf = buffer;
+
+		WARN_ON(count & 3);
+		while (count) {
+			__raw_writel((__force u32)(*buf), addr);
+			buf++;
+			count -= 4;
+		}
+		break;
+	}
+	default:
+		WARN_ON(1);
+	}
+}
+#endif /* CONFIG_BCMA_BLOCKIO */
+
+static u32 bcma_host_soc_aread32(struct bcma_device *core, u16 offset)
+{
+	return readl(core->io_wrap + offset);
+}
+
+static void bcma_host_soc_awrite32(struct bcma_device *core, u16 offset,
+				  u32 value)
+{
+	writel(value, core->io_wrap + offset);
+}
+
+const struct bcma_host_ops bcma_host_soc_ops = {
+	.read8		= bcma_host_soc_read8,
+	.read16		= bcma_host_soc_read16,
+	.read32		= bcma_host_soc_read32,
+	.write8		= bcma_host_soc_write8,
+	.write16	= bcma_host_soc_write16,
+	.write32	= bcma_host_soc_write32,
+#ifdef CONFIG_BCMA_BLOCKIO
+	.block_read	= bcma_host_soc_block_read,
+	.block_write	= bcma_host_soc_block_write,
+#endif
+	.aread32	= bcma_host_soc_aread32,
+	.awrite32	= bcma_host_soc_awrite32,
+};
+
+int __init bcma_host_soc_register(struct bcma_soc *soc)
+{
+	struct bcma_bus *bus = &soc->bus;
+	int err;
+
+	/* iomap only first core. We have to read some register on this core
+	 * to scan the bus.
+	 */
+	bus->mmio = ioremap_nocache(BCMA_ADDR_BASE, BCMA_CORE_SIZE * 1);
+	if (!bus->mmio)
+		return -ENOMEM;
+
+	/* Host specific */
+	bus->hosttype = BCMA_HOSTTYPE_SOC;
+	bus->ops = &bcma_host_soc_ops;
+
+	/* Register */
+	err = bcma_bus_early_register(bus, &soc->core_cc, &soc->core_mips);
+	if (err)
+		iounmap(bus->mmio);
+
+	return err;
+}

drivers/bcma/main.c

@@ -66,6 +66,10 @@ static struct bcma_device *bcma_find_core(struct bcma_bus *bus, u16 coreid)
 static void bcma_release_core_dev(struct device *dev)
 {
 	struct bcma_device *core = container_of(dev, struct bcma_device, dev);
+	if (core->io_addr)
+		iounmap(core->io_addr);
+	if (core->io_wrap)
+		iounmap(core->io_wrap);
 	kfree(core);
 }
 
@@ -93,7 +97,10 @@ static int bcma_register_cores(struct bcma_bus *bus)
 			core->dma_dev = &bus->host_pci->dev;
 			core->irq = bus->host_pci->irq;
 			break;
-		case BCMA_HOSTTYPE_NONE:
+		case BCMA_HOSTTYPE_SOC:
+			core->dev.dma_mask = &core->dev.coherent_dma_mask;
+			core->dma_dev = &core->dev;
+			break;
 		case BCMA_HOSTTYPE_SDIO:
 			break;
 		}

drivers/bcma/scan.c

@@ -337,6 +337,16 @@ static int bcma_get_next_core(struct bcma_bus *bus, u32 __iomem **eromptr,
 			}
 		}
 	}
+	if (bus->hosttype == BCMA_HOSTTYPE_SOC) {
+		core->io_addr = ioremap_nocache(core->addr, BCMA_CORE_SIZE);
+		if (!core->io_addr)
+			return -ENOMEM;
+		core->io_wrap = ioremap_nocache(core->wrap, BCMA_CORE_SIZE);
+		if (!core->io_wrap) {
+			iounmap(core->io_addr);
+			return -ENOMEM;
+		}
+	}
 	return 0;
 }
 
@@ -369,7 +379,14 @@ int bcma_bus_scan(struct bcma_bus *bus)
 	bcma_init_bus(bus);
 
 	erombase = bcma_scan_read32(bus, 0, BCMA_CC_EROM);
-	eromptr = bus->mmio;
+	if (bus->hosttype == BCMA_HOSTTYPE_SOC) {
+		eromptr = ioremap_nocache(erombase, BCMA_CORE_SIZE);
+		if (!eromptr)
+			return -ENOMEM;
+	} else {
+		eromptr = bus->mmio;
+	}
+
 	eromend = eromptr + BCMA_CORE_SIZE / sizeof(u32);
 
 	bcma_scan_switch_core(bus, erombase);
@@ -404,6 +421,9 @@ int bcma_bus_scan(struct bcma_bus *bus)
 		list_add(&core->list, &bus->cores);
 	}
 
+	if (bus->hosttype == BCMA_HOSTTYPE_SOC)
+		iounmap(eromptr);
+
 	return 0;
 }
 
@@ -414,10 +434,18 @@ int __init bcma_bus_scan_early(struct bcma_bus *bus,
 	u32 erombase;
 	u32 __iomem *eromptr, *eromend;
 
-	int err, core_num = 0;
+	int err = -ENODEV;
+	int core_num = 0;
 
 	erombase = bcma_scan_read32(bus, 0, BCMA_CC_EROM);
-	eromptr = bus->mmio;
+	if (bus->hosttype == BCMA_HOSTTYPE_SOC) {
+		eromptr = ioremap_nocache(erombase, BCMA_CORE_SIZE);
+		if (!eromptr)
+			return -ENOMEM;
+	} else {
+		eromptr = bus->mmio;
+	}
+
 	eromend = eromptr + BCMA_CORE_SIZE / sizeof(u32);
 
 	bcma_scan_switch_core(bus, erombase);
@@ -447,8 +475,12 @@ int __init bcma_bus_scan_early(struct bcma_bus *bus,
 			core->id.class);
 
 		list_add(&core->list, &bus->cores);
-		return 0;
+		err = 0;
+		break;
 	}
 
-	return -ENODEV;
+	if (bus->hosttype == BCMA_HOSTTYPE_SOC)
+		iounmap(eromptr);
+
+	return err;
 }

include/linux/bcma/bcma.h

@@ -14,9 +14,9 @@ struct bcma_device;
 struct bcma_bus;
 
 enum bcma_hosttype {
-	BCMA_HOSTTYPE_NONE,
 	BCMA_HOSTTYPE_PCI,
 	BCMA_HOSTTYPE_SDIO,
+	BCMA_HOSTTYPE_SOC,
 };
 
 struct bcma_chipinfo {
@@ -138,6 +138,9 @@ struct bcma_device {
 	u32 addr;
 	u32 wrap;
 
+	void __iomem *io_addr;
+	void __iomem *io_wrap;
+
 	void *drvdata;
 	struct list_head list;
 };

include/linux/bcma/bcma_soc.h

@@ -0,0 +1,16 @@
+#ifndef LINUX_BCMA_SOC_H_
+#define LINUX_BCMA_SOC_H_
+
+#include <linux/bcma/bcma.h>
+
+struct bcma_soc {
+	struct bcma_bus bus;
+	struct bcma_device core_cc;
+	struct bcma_device core_mips;
+};
+
+int __init bcma_host_soc_register(struct bcma_soc *soc);
+
+int bcma_bus_register(struct bcma_bus *bus);
+
+#endif /* LINUX_BCMA_SOC_H_ */