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

Provide kernel support for the tilegx "Transaction I/O" (TRIO) on-chip
hardware.  This hardware implements the PCIe interface for tilegx;
the driver changes to use TRIO for PCIe are in a subsequent commit.

The change is layered on top of the tilegx GXIO IORPC subsystem.

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

1 files changed, 49 insertions, 0 deletions

diff --git a/arch/tile/gxio/trio.c b/arch/tile/gxio/trio.c
new file mode 100644
index 000000000000..69f0b8df3ce3
--- /dev/null
+++ b/arch/tile/gxio/trio.c
@@ -0,0 +1,49 @@
+/*
+ * 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 trio gxio calls.
+ */
+
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/module.h>
+
+#include <gxio/trio.h>
+#include <gxio/iorpc_globals.h>
+#include <gxio/iorpc_trio.h>
+#include <gxio/kiorpc.h>
+
+int gxio_trio_init(gxio_trio_context_t *context, unsigned int trio_index)
+{
+	char file[32];
+	int fd;
+
+	snprintf(file, sizeof(file), "trio/%d/iorpc", trio_index);
+	fd = hv_dev_open((HV_VirtAddr) file, 0);
+	if (fd < 0) {
+		context->fd = -1;
+
+		if (fd >= GXIO_ERR_MIN && fd <= GXIO_ERR_MAX)
+			return fd;
+		else
+			return -ENODEV;
+	}
+
+	context->fd = fd;
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(gxio_trio_init);