Hello,
I'm porting a PCI driver to a RTDM. Until now, I have successfully done most of
the job.
I'm using Xenomai version 2.4.7 and Linux 2.6.27, from the ELinOS 5.0
distribution.
My problem appears with the rtdm_iomap_to_user() function. I want to allow a RT
task to access the PCI memory directly, via mmap. As the RTDM has no mmap()
function, I'm trying to use rtdm_iomap_to_user, but it always gives me the
following error:
I-pipe: Detected illicit call from domain 'Xenomai'
into a service reserved for domain 'Linux' and below.
Pid: 991, comm: demo Not tainted 2.6.27.31-ELinOS-59 #66
[<c013682b>] ipipe_check_context+0x90/0x9a
[<c017ca34>] kmem_cache_alloc+0x23/0xd2
[<c0180038>] ? get_empty_filp+0x51/0xc0
[<c010db8f>] ? mcount+0x1f/0x23
[<c0180038>] get_empty_filp+0x51/0xc0
[<c0186ba9>] __path_lookup_intent_open+0x1e/0x7b
[<c0186c1b>] path_lookup_open+0x15/0x17
[<c01875aa>] do_filp_open+0x82/0x5c8
[<c010db8f>] ? mcount+0x1f/0x23
[<c0187af8>] ? filp_open+0x8/0x1c
[<c0187b07>] filp_open+0x17/0x1c
[<c016383d>] rtdm_do_mmap+0x27/0xb3
[<c01638f8>] rtdm_iomap_to_user+0x2f/0x31
(...)
=======================
I-pipe tracer log (100 points):
+ func 0 ipipe_trace_panic_freeze+0x9
(ipipe_check_context+0x3f)
+ func 0 ipipe_check_context+0x9
(kmem_cache_alloc+0x23)
+ func 0 kmem_cache_alloc+0xe
(get_empty_filp+0x51)
+ func -1 get_empty_filp+0xa
(__path_lookup_intent_open+0x1e)
+ func -2 __path_lookup_intent_open+0xe
(path_lookup_open+0x15)
+ func -2 path_lookup_open+0x8 (do_filp_open+0x82)
+ func -3 do_filp_open+0xe (filp_open+0x17)
+ func -4 filp_open+0x8 (rtdm_do_mmap+0x27)
+ func -4 rtdm_do_mmap+0xe
(rtdm_iomap_to_user+0x2f)
+ func -5 rtdm_iomap_to_user+0xb
(filstrup_rt_ioctl+0x102 [filstrup1_drv])
(...)
filstrup1_drv: rtdm_mmap = b5f02000 (retval 0)
filstrup1_drv: rtdm_mmap = b5f02000 (retval 0)
My code is the following (simplified):
struct xen_mydriver_context *xen_mydriver;
int mydriver_rt_ioctl(struct rtdm_dev_context *context,
rtdm_user_info_t *user_info, unsigned int cmd, void *arg)
{
(...)
my_context = (struct xen_mydriver_context
*)context->dev_private;
switch(cmd)
{
case IOCTL_MMAP:
retval =
rtdm_iomap_to_user(user_info,my_context->location, 300, PROT_READ|PROT_WRITE,
(void**)arg, NULL, NULL);
break;
(...)
}
static int __devinit mydriver_probe(struct pci_dev *dev, const struct
pci_device_id *id)
{
struct rtdm_device *rtdm_dev;
(...)
ret_val = pci_enable_device(dev);
(...)
xen_mydriver->location = pci_resource_start(dev,0); //
Physical address
xen_mydriver->mem_size = pci_resource_len(dev,0);
rtdm_dev = rtdm_malloc(sizeof(struct rtdm_device));
(...)
request_mem_region(xen_mydriver->location,
xen_mydriver->mem_size, rtdm_dev->device_name);
xen_mydriver->base_address = ioremap(xen_mydriver->location,
xen_mydriver->mem_size);
(...)
ret_val = rtdm_dev_register(rtdm_dev);
}
The value of xen_mydriver->location is 0x20000000. The value of
xen_mydriver->base_address is 0xe0a00000.
My driver runs correctly until I call the IOCTL_MMAP ioctl. I can write to the
PCI device directly in the RTDM driver by using the xen_mydriver->base_address
pointer, but can't do it from the RT task.
I have searched the lists, but found no piece of information that could help
me. I've found some clues (pci_alloc_consistent, rt_heap_*, /dev/rtheap, ...),
but it has been impossible for me to solve this problem.
Can anyone help me with this issue? Has anyone got an example of how to use
rtdm_iomap_to_user()?
Thanks in advance,
Asier
_______________________________________________
Xenomai-help mailing list
[email protected]
https://mail.gna.org/listinfo/xenomai-help
