Hi
(After some confusion about kernel version, I think I found the
problem, sorry about that).
I used binutils 2.15 and 2.16.1, but did not work.
The code in the ehci-hcd.c looks like this:
----------------------------------------------------------------------------
ehci->periodic_size = DEFAULT_I_TDPS;
if ((retval = ehci_mem_init(ehci, GFP_KERNEL)) < 0)
return retval;
/* controllers may cache some of the periodic schedule ... */
hcc_params = readl(&ehci->caps->hcc_params);
if (HCC_ISOC_CACHE(hcc_params)) // full frame cache
ehci->i_thresh = 8;
else // N microframes cached
ehci->i_thresh = 2 + HCC_ISOC_THRES(hcc_params);
----------------------------------------------------------------------------
The problem is *AFTER* the call to ehci_mem_init, where a read from
ehci->caps->hcc_params is attempted, but caps is NULL.
This can be seen by this assembly code form Insight:
----------------------------------------------------------------------------
0x80350758 jal 0x802a3f40 <memset>
0x8035075c sll a2,a2,0x2
0x80350760 lw v1,0(s0)
0x80350764 lw a2,8(v1)
s0 points to ehci
at offset 0 from ehci is caps
and at offset 8 from caps is hcc_params
----------------------------------------------------------------------------
Where should the caps be initialized?
The only place, where it is set in drivers/usb/ is in
drivers/usb/host/ehci-pci.c:
----------------------------------------------------------------------------
/* called during probe() after chip reset completes */
static int ehci_pci_setup(struct usb_hcd *hcd)
{
struct ehci_hcd *ehci = hcd_to_ehci(hcd);
struct pci_dev *pdev =
to_pci_dev(hcd->self.controller);
u32 temp;
int retval;
ehci->caps = hcd->regs;
----------------------------------------------------------------------------
But the ehci-pci.c is not included in the compilation, because at the
end of ehci-hcd.c we find:
----------------------------------------------------------------------------
#if defined(CONFIG_SOC_AU1X00)
#include "ehci-au1xxx.c"
#elif defined(CONFIG_PCI)
#include "ehci-pci.c"
#else
#error "missing bus glue for ehci-hcd"
#endif
----------------------------------------------------------------------------
What should be done?
I hope this helps.
BR,
Matej
-------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc. Do you grep through log files
for problems? Stop! Download the new AJAX search engine that makes
searching your log files as easy as surfing the web. DOWNLOAD SPLUNK!
http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
