arch/tile: provide kernel support for the tilegx USB shim

This change adds support for accessing the USB shim from within the
kernel.  Note that this change by itself does not allow the kernel
to act as a host or as a device; it merely exposes the built-in on-chip
hardware to the kernel.

The <arch/usb_host.h> and <arch/usb_host_def.h> headers are empty at
the moment because the kernel does not require any types or definitions
specific to the tilegx USB shim; the generic USB core code is all we need.
The headers are left in as stubs so that we don't need to modify the
hypervisor header (drv_usb_host_intf.h) from upstream.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

arch/tile/gxio/Kconfig

@@ -21,3 +21,8 @@ config TILE_GXIO_TRIO
 	bool
 	select TILE_GXIO
 	select TILE_GXIO_DMA
+
+# Support direct access to the TILE-Gx USB hardware from kernel space.
+config TILE_GXIO_USB_HOST
+	bool
+	select TILE_GXIO

arch/tile/gxio/Makefile

@@ -6,3 +6,4 @@ obj-$(CONFIG_TILE_GXIO) += iorpc_globals.o kiorpc.o
 obj-$(CONFIG_TILE_GXIO_DMA) += dma_queue.o
 obj-$(CONFIG_TILE_GXIO_MPIPE) += mpipe.o iorpc_mpipe.o iorpc_mpipe_info.o
 obj-$(CONFIG_TILE_GXIO_TRIO) += trio.o iorpc_trio.o
+obj-$(CONFIG_TILE_GXIO_USB_HOST) += usb_host.o iorpc_usb_host.o

arch/tile/gxio/iorpc_usb_host.c

@@ -0,0 +1,99 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/* This file is machine-generated; DO NOT EDIT! */
+#include "gxio/iorpc_usb_host.h"
+
+struct cfg_interrupt_param {
+	union iorpc_interrupt interrupt;
+};
+
+int gxio_usb_host_cfg_interrupt(gxio_usb_host_context_t * context, int inter_x,
+				int inter_y, int inter_ipi, int inter_event)
+{
+	struct cfg_interrupt_param temp;
+	struct cfg_interrupt_param *params = &temp;
+
+	params->interrupt.kernel.x = inter_x;
+	params->interrupt.kernel.y = inter_y;
+	params->interrupt.kernel.ipi = inter_ipi;
+	params->interrupt.kernel.event = inter_event;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params), GXIO_USB_HOST_OP_CFG_INTERRUPT);
+}
+
+EXPORT_SYMBOL(gxio_usb_host_cfg_interrupt);
+
+struct register_client_memory_param {
+	HV_PTE pte;
+	unsigned int flags;
+};
+
+int gxio_usb_host_register_client_memory(gxio_usb_host_context_t * context,
+					 HV_PTE pte, unsigned int flags)
+{
+	struct register_client_memory_param temp;
+	struct register_client_memory_param *params = &temp;
+
+	params->pte = pte;
+	params->flags = flags;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_USB_HOST_OP_REGISTER_CLIENT_MEMORY);
+}
+
+EXPORT_SYMBOL(gxio_usb_host_register_client_memory);
+
+struct get_mmio_base_param {
+	HV_PTE base;
+};
+
+int gxio_usb_host_get_mmio_base(gxio_usb_host_context_t * context, HV_PTE *base)
+{
+	int __result;
+	struct get_mmio_base_param temp;
+	struct get_mmio_base_param *params = &temp;
+
+	__result =
+	    hv_dev_pread(context->fd, 0, (HV_VirtAddr) params, sizeof(*params),
+			 GXIO_USB_HOST_OP_GET_MMIO_BASE);
+	*base = params->base;
+
+	return __result;
+}
+
+EXPORT_SYMBOL(gxio_usb_host_get_mmio_base);
+
+struct check_mmio_offset_param {
+	unsigned long offset;
+	unsigned long size;
+};
+
+int gxio_usb_host_check_mmio_offset(gxio_usb_host_context_t * context,
+				    unsigned long offset, unsigned long size)
+{
+	struct check_mmio_offset_param temp;
+	struct check_mmio_offset_param *params = &temp;
+
+	params->offset = offset;
+	params->size = size;
+
+	return hv_dev_pwrite(context->fd, 0, (HV_VirtAddr) params,
+			     sizeof(*params),
+			     GXIO_USB_HOST_OP_CHECK_MMIO_OFFSET);
+}
+
+EXPORT_SYMBOL(gxio_usb_host_check_mmio_offset);

arch/tile/gxio/usb_host.c

@@ -0,0 +1,91 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/*
+ *
+ * Implementation of USB gxio calls.
+ */
+
+#include <linux/io.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+
+#include <gxio/iorpc_globals.h>
+#include <gxio/iorpc_usb_host.h>
+#include <gxio/kiorpc.h>
+#include <gxio/usb_host.h>
+
+int gxio_usb_host_init(gxio_usb_host_context_t * context, int usb_index,
+		       int is_ehci)
+{
+	char file[32];
+	int fd;
+
+	if (is_ehci)
+		snprintf(file, sizeof(file), "usb_host/%d/iorpc/ehci",
+			 usb_index);
+	else
+		snprintf(file, sizeof(file), "usb_host/%d/iorpc/ohci",
+			 usb_index);
+
+	fd = hv_dev_open((HV_VirtAddr) file, 0);
+	if (fd < 0) {
+		if (fd >= GXIO_ERR_MIN && fd <= GXIO_ERR_MAX)
+			return fd;
+		else
+			return -ENODEV;
+	}
+
+	context->fd = fd;
+
+	// Map in the MMIO space.
+	context->mmio_base =
+		(void __force *)iorpc_ioremap(fd, 0, HV_USB_HOST_MMIO_SIZE);
+
+	if (context->mmio_base == NULL) {
+		hv_dev_close(context->fd);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_usb_host_init);
+
+int gxio_usb_host_destroy(gxio_usb_host_context_t * context)
+{
+	iounmap((void __force __iomem *)(context->mmio_base));
+	hv_dev_close(context->fd);
+
+	context->mmio_base = NULL;
+	context->fd = -1;
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_usb_host_destroy);
+
+void *gxio_usb_host_get_reg_start(gxio_usb_host_context_t * context)
+{
+	return context->mmio_base;
+}
+
+EXPORT_SYMBOL_GPL(gxio_usb_host_get_reg_start);
+
+size_t gxio_usb_host_get_reg_len(gxio_usb_host_context_t * context)
+{
+	return HV_USB_HOST_MMIO_SIZE;
+}
+
+EXPORT_SYMBOL_GPL(gxio_usb_host_get_reg_len);

arch/tile/include/arch/usb_host.h

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/* Machine-generated file; do not edit. */
+
+#ifndef __ARCH_USB_HOST_H__
+#define __ARCH_USB_HOST_H__
+
+#include <arch/abi.h>
+#include <arch/usb_host_def.h>
+
+#ifndef __ASSEMBLER__
+#endif /* !defined(__ASSEMBLER__) */
+
+#endif /* !defined(__ARCH_USB_HOST_H__) */

arch/tile/include/arch/usb_host_def.h

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/* Machine-generated file; do not edit. */
+
+#ifndef __ARCH_USB_HOST_DEF_H__
+#define __ARCH_USB_HOST_DEF_H__
+#endif /* !defined(__ARCH_USB_HOST_DEF_H__) */

arch/tile/include/gxio/iorpc_usb_host.h

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/* This file is machine-generated; DO NOT EDIT! */
+#ifndef __GXIO_USB_HOST_LINUX_RPC_H__
+#define __GXIO_USB_HOST_LINUX_RPC_H__
+
+#include <hv/iorpc.h>
+
+#include <hv/drv_usb_host_intf.h>
+#include <asm/page.h>
+#include <gxio/kiorpc.h>
+#include <gxio/usb_host.h>
+#include <linux/string.h>
+#include <linux/module.h>
+#include <asm/pgtable.h>
+
+#define GXIO_USB_HOST_OP_CFG_INTERRUPT IORPC_OPCODE(IORPC_FORMAT_KERNEL_INTERRUPT, 0x1800)
+#define GXIO_USB_HOST_OP_REGISTER_CLIENT_MEMORY IORPC_OPCODE(IORPC_FORMAT_NONE_NOUSER, 0x1801)
+#define GXIO_USB_HOST_OP_GET_MMIO_BASE IORPC_OPCODE(IORPC_FORMAT_NONE_NOUSER, 0x8000)
+#define GXIO_USB_HOST_OP_CHECK_MMIO_OFFSET IORPC_OPCODE(IORPC_FORMAT_NONE_NOUSER, 0x8001)
+
+int gxio_usb_host_cfg_interrupt(gxio_usb_host_context_t * context, int inter_x,
+				int inter_y, int inter_ipi, int inter_event);
+
+int gxio_usb_host_register_client_memory(gxio_usb_host_context_t * context,
+					 HV_PTE pte, unsigned int flags);
+
+int gxio_usb_host_get_mmio_base(gxio_usb_host_context_t * context,
+				HV_PTE *base);
+
+int gxio_usb_host_check_mmio_offset(gxio_usb_host_context_t * context,
+				    unsigned long offset, unsigned long size);
+
+#endif /* !__GXIO_USB_HOST_LINUX_RPC_H__ */

arch/tile/include/gxio/usb_host.h

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+#ifndef _GXIO_USB_H_
+#define _GXIO_USB_H_
+
+#include "common.h"
+
+#include <hv/drv_usb_host_intf.h>
+#include <hv/iorpc.h>
+
+/*
+ *
+ * An API for manipulating general-purpose I/O pins.
+ */
+
+/*
+ *
+ * The USB shim allows access to the processor's Universal Serial Bus
+ * connections.
+ */
+
+/* A context object used to manage USB hardware resources. */
+typedef struct {
+
+	/* File descriptor for calling up to the hypervisor. */
+	int fd;
+
+	/* The VA at which our MMIO registers are mapped. */
+	char *mmio_base;
+} gxio_usb_host_context_t;
+
+/* Initialize a USB context.
+ *
+ *  A properly initialized context must be obtained before any of the other
+ *  gxio_usb_host routines may be used.
+ *
+ * @param context Pointer to a gxio_usb_host_context_t, which will be
+ *  initialized by this routine, if it succeeds.
+ * @param usb_index Index of the USB shim to use.
+ * @param is_ehci Nonzero to use the EHCI interface; zero to use the OHCI
+ *  intereface.
+ * @return Zero if the context was successfully initialized, else a
+ *  GXIO_ERR_xxx error code.
+ */
+extern int gxio_usb_host_init(gxio_usb_host_context_t * context, int usb_index,
+			      int is_ehci);
+
+/* Destroy a USB context.
+ *
+ *  Once destroyed, a context may not be used with any gxio_usb_host routines
+ *  other than gxio_usb_host_init().  After this routine returns, no further
+ *  interrupts or signals requested on this context will be delivered.  The
+ *  state and configuration of the pins which had been attached to this
+ *  context are unchanged by this operation.
+ *
+ * @param context Pointer to a gxio_usb_host_context_t.
+ * @return Zero if the context was successfully destroyed, else a
+ *  GXIO_ERR_xxx error code.
+ */
+extern int gxio_usb_host_destroy(gxio_usb_host_context_t * context);
+
+/* Retrieve the address of the shim's MMIO registers.
+ *
+ * @param context Pointer to a properly initialized gxio_usb_host_context_t.
+ * @return The address of the shim's MMIO registers.
+ */
+extern void *gxio_usb_host_get_reg_start(gxio_usb_host_context_t * context);
+
+/* Retrieve the length of the shim's MMIO registers.
+ *
+ * @param context Pointer to a properly initialized gxio_usb_host_context_t.
+ * @return The length of the shim's MMIO registers.
+ */
+extern size_t gxio_usb_host_get_reg_len(gxio_usb_host_context_t * context);
+
+#endif /* _GXIO_USB_H_ */

arch/tile/include/hv/drv_usb_host_intf.h

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2012 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+/**
+ * Interface definitions for the USB host driver.
+ */
+
+#ifndef _SYS_HV_DRV_USB_HOST_INTF_H
+#define _SYS_HV_DRV_USB_HOST_INTF_H
+
+#include <arch/usb_host.h>
+
+
+/** Offset for the EHCI register MMIO region. */
+#define HV_USB_HOST_MMIO_OFFSET_EHCI ((uint64_t) USB_HOST_HCCAPBASE_REG)
+
+/** Offset for the OHCI register MMIO region. */
+#define HV_USB_HOST_MMIO_OFFSET_OHCI ((uint64_t) USB_HOST_OHCD_HC_REVISION_REG)
+
+/** Size of the register MMIO region.  This turns out to be the same for
+ *  both EHCI and OHCI. */
+#define HV_USB_HOST_MMIO_SIZE ((uint64_t) 0x1000)
+
+/** The number of service domains supported by the USB host shim. */
+#define HV_USB_HOST_NUM_SVC_DOM 1
+
+
+#endif /* _SYS_HV_DRV_USB_HOST_INTF_H */