From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- arch/arc/kernel/arc_hostlink.c | 55 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 arch/arc/kernel/arc_hostlink.c (limited to 'arch/arc/kernel/arc_hostlink.c') diff --git a/arch/arc/kernel/arc_hostlink.c b/arch/arc/kernel/arc_hostlink.c new file mode 100644 index 000000000..08c5196ef --- /dev/null +++ b/arch/arc/kernel/arc_hostlink.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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) + */ + +#include /* file_operations */ +#include +#include /* VM_IO */ +#include +#include + +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); -- cgit v1.2.3