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authorVineet Gupta <vgupta@synopsys.com>2013-01-18 15:12:25 +0530
committerVineet Gupta <vgupta@synopsys.com>2013-02-15 23:16:10 +0530
commitcbe056f76a386708f3807b274322f78269aee0f6 (patch)
treea64ad404b3f912c3885881b32aba3b5559b3333a /arch/arc/kernel
parent8b5850f8ac8d9b809db4588b80b568faca5aaaaf (diff)
downloadvexpress-lsk-cbe056f76a386708f3807b274322f78269aee0f6.tar.gz
ARC: Hostlink Pseudo-Driver for Metaware Debugger
This allows ARC Target to do I/O to host in absence of any peripherals whatsoever, assisted by Metaware Hostlink facility. Further we have a FUSE based filesystem which makes us mount/access host filesystem on target and do fops. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc/kernel')
-rw-r--r--arch/arc/kernel/Makefile1
-rw-r--r--arch/arc/kernel/arc_hostlink.c58
2 files changed, 59 insertions, 0 deletions
diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile
index 6da2b12cf7e..c242ef07ba7 100644
--- a/arch/arc/kernel/Makefile
+++ b/arch/arc/kernel/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_ARC_DW2_UNWIND) += unwind.o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_ARC_MISALIGN_ACCESS) += unaligned.o
obj-$(CONFIG_KGDB) += kgdb.o
+obj-$(CONFIG_ARC_METAWARE_HLINK) += arc_hostlink.o
obj-$(CONFIG_ARC_FPU_SAVE_RESTORE) += fpu.o
CFLAGS_fpu.o += -mdpfp
diff --git a/arch/arc/kernel/arc_hostlink.c b/arch/arc/kernel/arc_hostlink.c
new file mode 100644
index 00000000000..47b2a17cc52
--- /dev/null
+++ b/arch/arc/kernel/arc_hostlink.c
@@ -0,0 +1,58 @@
+/*
+ * arc_hostlink.c: Pseudo-driver for Metaware provided "hostlink" facility
+ *
+ * Allows Linux userland access to host in absence of any peripherals.
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/fs.h> /* file_operations */
+#include <linux/miscdevice.h>
+#include <linux/mm.h> /* VM_IO */
+#include <linux/module.h>
+#include <linux/uaccess.h>
+
+static unsigned char __HOSTLINK__[4 * PAGE_SIZE] __aligned(PAGE_SIZE);
+
+static int arc_hl_mmap(struct file *fp, struct vm_area_struct *vma)
+{
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+ if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+ vma->vm_end - vma->vm_start,
+ vma->vm_page_prot)) {
+ pr_warn("Hostlink buffer mmap ERROR\n");
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+static long arc_hl_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ /* we only support, returning the physical addr to mmap in user space */
+ put_user((unsigned int)__HOSTLINK__, (int __user *)arg);
+ return 0;
+}
+
+static const struct file_operations arc_hl_fops = {
+ .unlocked_ioctl = arc_hl_ioctl,
+ .mmap = arc_hl_mmap,
+};
+
+static struct miscdevice arc_hl_dev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "hostlink",
+ .fops = &arc_hl_fops
+};
+
+static int __init arc_hl_init(void)
+{
+ pr_info("ARC Hostlink driver mmap at 0x%p\n", __HOSTLINK__);
+ return misc_register(&arc_hl_dev);
+}
+module_init(arc_hl_init);