USB hangs on AU1100

USB hangs on AU1100

[Rodolfo Giometti]

Hello,

I'm just using USB host support on a AU1100 developing board (DB1100
configuration) and i notice that CPU locks in function
au1xxx_start_hc():

        /* wait for reset complete (read register twice; see au1500 errata) */
        while (au_readl(USB_HOST_CONFIG),
                !(au_readl(USB_HOST_CONFIG) & USBH_ENABLE_RD))
                udelay(1000);

while waiting for USB controller to reset. I checked it out and I
discovered that register USB_HOST_CONFIG is fixed at value 0xe! So the
controller never reset...

Linux is 2.6.12-rc3 from CVS.

Someone knows whats wrong?

Thanks in advance,

Rodolfo Giometti

-- 

GNU/Linux Solutions                  e-mail:    giometti@linux.it
Linux Device Driver                             giometti@enneenne.com
Embedded Systems                     home page: giometti.enneenne.com
UNIX programming                     phone:     +39 349 2432127

Re: USB hangs on AU1100

[Pete Popov]

On Thu, 2005-05-05 at 17:54 +0200, Rodolfo Giometti wrote:
> Hello,
> 
> I'm just using USB host support on a AU1100 developing board (DB1100
> configuration) and i notice that CPU locks in function
> au1xxx_start_hc():
> 
>         /* wait for reset complete (read register twice; see au1500 errata) */
>         while (au_readl(USB_HOST_CONFIG),
>                 !(au_readl(USB_HOST_CONFIG) & USBH_ENABLE_RD))
>                 udelay(1000);
> 
> while waiting for USB controller to reset. I checked it out and I
> discovered that register USB_HOST_CONFIG is fixed at value 0xe! So the
> controller never reset...
> 
> Linux is 2.6.12-rc3 from CVS.
> 
> Someone knows whats wrong?

It sounds like this is a custom Au1100 based board? What boot code are
you running?  I'm guessing the SOC isn't setup correctly or you have a
HW problem.

Pete

Re: USB hangs on AU1100

[Thiemo Seufer]

Pete Popov wrote:
> On Thu, 2005-05-05 at 17:54 +0200, Rodolfo Giometti wrote:
> > Hello,
> > 
> > I'm just using USB host support on a AU1100 developing board (DB1100
> > configuration) and i notice that CPU locks in function
> > au1xxx_start_hc():
> > 
> >         /* wait for reset complete (read register twice; see au1500 errata) */
> >         while (au_readl(USB_HOST_CONFIG),
> >                 !(au_readl(USB_HOST_CONFIG) & USBH_ENABLE_RD))
> >                 udelay(1000);
> > 
> > while waiting for USB controller to reset. I checked it out and I
> > discovered that register USB_HOST_CONFIG is fixed at value 0xe! So the
> > controller never reset...
> > 
> > Linux is 2.6.12-rc3 from CVS.
> > 
> > Someone knows whats wrong?
> 
> It sounds like this is a custom Au1100 based board? What boot code are
> you running?  I'm guessing the SOC isn't setup correctly or you have a
> HW problem.

I wonder if the code works reliable. At least, a comma operator isn't a
sequence point, which means the compiler is free to change the execution
order.


Thiemo

Re: USB hangs on AU1100

[Maciej W. Rozycki]

On Thu, 5 May 2005, Thiemo Seufer wrote:

> > > I'm just using USB host support on a AU1100 developing board (DB1100
> > > configuration) and i notice that CPU locks in function
> > > au1xxx_start_hc():
> > > 
> > >         /* wait for reset complete (read register twice; see au1500 errata) */
> > >         while (au_readl(USB_HOST_CONFIG),
> > >                 !(au_readl(USB_HOST_CONFIG) & USBH_ENABLE_RD))
> > >                 udelay(1000);
> > > 
> > > while waiting for USB controller to reset. I checked it out and I
> > > discovered that register USB_HOST_CONFIG is fixed at value 0xe! So the
> > > controller never reset...
> > > 
> > > Linux is 2.6.12-rc3 from CVS.
> > > 
> > > Someone knows whats wrong?
> > 
> > It sounds like this is a custom Au1100 based board? What boot code are
> > you running?  I'm guessing the SOC isn't setup correctly or you have a
> > HW problem.
> 
> I wonder if the code works reliable. At least, a comma operator isn't a
> sequence point, which means the compiler is free to change the execution
> order.

 Good point -- even though the code is valid C, it's complete rubbish.  
I'd suggest rewriting it to get something readable first.

  Maciej

Re: USB hangs on AU1100

[Ulrich Teichert]

Hi,

[del]
>I wonder if the code works reliable. At least, a comma operator isn't a
>sequence point, which means the compiler is free to change the execution
>order.

Not accordingly to the C standard, which notes strict left-to-right
execution without reordering for the comma operator.

HTH,
Uli
-- 
Dipl. Inf. Ulrich Teichert|e-mail: Ulrich.Teichert@gmx.de
Stormweg 24               |listening to: Suicide Drive (The Deep Eynde)
24539 Neumuenster, Germany|Public Pervert (Interpol) Cauchemar (Opération S)

Re: USB hangs on AU1100

[Ulrich Teichert]

Hi,

[del]
>I wonder if the code works reliable. At least, a comma operator isn't a
>sequence point, which means the compiler is free to change the execution
>order.

Not accordingly to the C standard, which notes strict left-to-right
execution without reordering for the comma operator.

HTH,
Uli
-- 
Dipl. Inf. Ulrich Teichert|e-mail: Ulrich.Teichert@gmx.de
Stormweg 24               |listening to: Suicide Drive (The Deep Eynde)
24539 Neumuenster, Germany|Public Pervert (Interpol) Cauchemar (Opération S)

Re: USB hangs on AU1100

[Pete Popov]

On Thu, 2005-05-05 at 18:51 +0100, Maciej W. Rozycki wrote:
> On Thu, 5 May 2005, Thiemo Seufer wrote:
> 
> > > > I'm just using USB host support on a AU1100 developing board (DB1100
> > > > configuration) and i notice that CPU locks in function
> > > > au1xxx_start_hc():
> > > > 
> > > >         /* wait for reset complete (read register twice; see au1500 errata) */
> > > >         while (au_readl(USB_HOST_CONFIG),
> > > >                 !(au_readl(USB_HOST_CONFIG) & USBH_ENABLE_RD))
> > > >                 udelay(1000);
> > > > 
> > > > while waiting for USB controller to reset. I checked it out and I
> > > > discovered that register USB_HOST_CONFIG is fixed at value 0xe! So the
> > > > controller never reset...
> > > > 
> > > > Linux is 2.6.12-rc3 from CVS.
> > > > 
> > > > Someone knows whats wrong?
> > > 
> > > It sounds like this is a custom Au1100 based board? What 
> oot code are
> > > you running?  I'm guessing the SOC isn't setup correctly or you have a
> > > HW problem.
> > 
> > I wonder if the code works reliable. At least, a comma operator isn't a
> > sequence point, which means the compiler is free to change the execution
> > order.
> 
>  Good point -- even though the code is valid C, it's complete rubbish.  
> I'd suggest rewriting it to get something readable first.

Interesting. I hadn't looked at this chunk of code before.

Pete

Re: USB hangs on AU1100

[Thiemo Seufer]

Ulrich Teichert wrote:
> Hi,
> 
> [del]
> >I wonder if the code works reliable. At least, a comma operator isn't a
> >sequence point, which means the compiler is free to change the execution
> >order.
> 
> Not accordingly to the C standard, which notes strict left-to-right
> execution without reordering for the comma operator.

You are right, apparently I remembered incorrectly.


Thiemo

Re: USB hangs on AU1100

[Rodolfo Giometti]

[-- Attachment #1: Type: text/plain, Size: 748 bytes --]

On Thu, May 05, 2005 at 09:42:41AM -0700, Pete Popov wrote:
> It sounds like this is a custom Au1100 based board? What boot code are

Yes, but is very close to the DB1100.

> you running?  I'm guessing the SOC isn't setup correctly or you have a
> HW problem.

I selected the code for the DB1100... I'm very puzzled about this
problem!

However let me suggest you this little patch in order to advice the
user about this problem and to avoid system locks.

Ciao,

Rodolfo

-- 

GNU/Linux Solutions                  e-mail:    giometti@linux.it
Linux Device Driver                             giometti@enneenne.com
Embedded Systems                     home page: giometti.enneenne.com
UNIX programming                     phone:     +39 349 2432127

[-- Attachment #2: patch --]
[-- Type: text/plain, Size: 1564 bytes --]

Index: ohci-au1xxx.c
===================================================================
RCS file: /home/cvs/linux/drivers/usb/host/ohci-au1xxx.c,v
retrieving revision 1.5
diff -u -r1.5 ohci-au1xxx.c
--- ohci-au1xxx.c	3 Apr 2005 20:39:19 -0000	1.5
+++ ohci-au1xxx.c	6 May 2005 09:14:35 -0000
@@ -38,8 +38,10 @@
 
 /*-------------------------------------------------------------------------*/
 
-static void au1xxx_start_hc(struct platform_device *dev)
+static int au1xxx_start_hc(struct platform_device *dev)
 {
+	int count = 3000;
+
 	printk(KERN_DEBUG __FILE__
 		": starting Au1xxx OHCI USB Controller\n");
 
@@ -51,11 +53,19 @@
 
 	/* wait for reset complete (read register twice; see au1500 errata) */
 	while (au_readl(USB_HOST_CONFIG),
-		!(au_readl(USB_HOST_CONFIG) & USBH_ENABLE_RD)) 
+		!(au_readl(USB_HOST_CONFIG) & USBH_ENABLE_RD)) {
 		udelay(1000);
+		if (--count == 0) {
+			printk(KERN_ERR __FILE__
+			": unable to reset USB host\n");
+			return -EBUSY;
+		}
+	}
 
 	printk(KERN_DEBUG __FILE__
 	": Clock to USB host has been enabled \n");
+
+	return 0;
 }
 
 static void au1xxx_stop_hc(struct platform_device *dev)
@@ -113,7 +123,11 @@
 		goto err2;
 	}
 
-	au1xxx_start_hc(dev);
+	retval = au1xxx_start_hc(dev);
+	if (retval < 0) {
+		pr_debug("au1xxx start failed");
+		goto err3;
+	}
 	ohci_hcd_init(hcd_to_ohci(hcd));
 
 	retval = usb_add_hcd(hcd, dev->resource[1].start, SA_INTERRUPT);
@@ -121,6 +135,7 @@
 		return retval;
 
 	au1xxx_stop_hc(dev);
+ err3:
 	iounmap(hcd->regs);
  err2:
 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);

Re: USB hangs on AU1100

[Rodolfo Giometti]

[-- Attachment #1: Type: text/plain, Size: 2340 bytes --]

On Thu, May 05, 2005 at 09:42:41AM -0700, Pete Popov wrote:
> It sounds like this is a custom Au1100 based board? What boot code are
> you running?  I'm guessing the SOC isn't setup correctly or you have a
> HW problem.

Yes, you was right, I missing to setup USB clock... I just added this
code to the board init function (board_setup() function) and now USB
works:

    #if defined(CONFIG_USB_OHCI_HCD) || defined(CONFIG_AU1X00_USB_DEVICE)
	    /* zero and disable FREQ2 */
	    sys_freqctrl = au_readl(SYS_FREQCTRL0);
	    sys_freqctrl &= ~0xFFF00000;
	    au_writel(sys_freqctrl, SYS_FREQCTRL0);
    
	    /* zero and disable USBH/USBD/IrDA clock */
	    sys_clksrc = au_readl(SYS_CLKSRC);
	    sys_clksrc &= ~0x0000001F;
	    au_writel(sys_clksrc, SYS_CLKSRC);
    
	    sys_freqctrl = au_readl(SYS_FREQCTRL0);
	    sys_freqctrl &= ~0xFFF00000;
    
	    sys_clksrc = au_readl(SYS_CLKSRC);
	    sys_clksrc &= ~0x0000001F;
    
	    /* FREQ2 = aux/2 = 48 MHz */
	    sys_freqctrl |= ((0<<22) | (1<<21) | (1<<20));
	    au_writel(sys_freqctrl, SYS_FREQCTRL0);
    
	    /* Route 48MHz FREQ2 into USBH/USBD/IrDA */
	    sys_clksrc |= ((4<<2) | (0<<1) | 0 );
	    au_writel(sys_clksrc, SYS_CLKSRC);
    
	    /* setup the static bus controller */
	    au_writel(0x00000002, MEM_STCFG3);  /* type = PCMCIA */
	    au_writel(0x280E3D07, MEM_STTIME3); /* 250ns cycle time */
	    au_writel(0x10000000, MEM_STADDR3); /* any PCMCIA select */
    
	    /* Get USB Functionality pin state (device vs host drive pins) */
	    pin_func = au_readl(SYS_PINFUNC) & (u32)(~0x8000);
    #ifndef CONFIG_AU1X00_USB_DEVICE
	    /* 2nd USB port is USB host */
	    pin_func |= 0x8000;
    #endif
	    au_writel(pin_func, SYS_PINFUNC);
    #endif /* defined (CONFIG_USB_OHCI_HCD) || defined (CONFIG_AU1X00_USB_DEVICE) */

But don't you think is better to put this code into USB driver (file
ohci-au1xxx.c) during probing stage? In this manner each platforms may
don't worry about clock initialization...

Ciao,

Rodolfo

-- 

GNU/Linux Solutions                  e-mail:    giometti@linux.it
Linux Device Driver                             giometti@enneenne.com
Embedded Systems                     home page: giometti.enneenne.com
UNIX programming                     phone:     +39 349 2432127

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Re: USB hangs on AU1100

[Dan Malek]

On May 6, 2005, at 10:27 AM, Rodolfo Giometti wrote:

> Yes, you was right, I missing to setup USB clock...

The other thing you have to always remember when comparing
operation to "... a board just like the Db1xxx ... " is that yamon does
lots and lots of set up for the board that Linux assumes will be
done.  We've discussed this in the past, I just wanted to mention
it again so it isn't forgotten. ;-)

Thanks.


	-- Dan

Re: USB hangs on AU1100

[Pete Popov]

On Fri, 2005-05-06 at 16:27 +0200, Rodolfo Giometti wrote:
> On Thu, May 05, 2005 at 09:42:41AM -0700, Pete Popov wrote:
> > It sounds like this is a custom Au1100 based board? What boot code are
> > you running?  I'm guessing the SOC isn't setup correctly or you have a
> > HW problem.
> 
> Yes, you was right, I missing to setup USB clock... I just added this
> code to the board init function (board_setup() function) and now USB
> works:
> 
>     #if defined(CONFIG_USB_OHCI_HCD) || defined(CONFIG_AU1X00_USB_DEVICE)
> 	    /* zero and disable FREQ2 */
> 	    sys_freqctrl = au_readl(SYS_FREQCTRL0);
> 	    sys_freqctrl &= ~0xFFF00000;
> 	    au_writel(sys_freqctrl, SYS_FREQCTRL0);
>     
> 	    /* zero and disable USBH/USBD/IrDA clock */
> 	    sys_clksrc = au_readl(SYS_CLKSRC);
> 	    sys_clksrc &= ~0x0000001F;
> 	    au_writel(sys_clksrc, SYS_CLKSRC);
>     
> 	    sys_freqctrl = au_readl(SYS_FREQCTRL0);
> 	    sys_freqctrl &= ~0xFFF00000;
>     
> 	    sys_clksrc = au_readl(SYS_CLKSRC);
> 	    sys_clksrc &= ~0x0000001F;
>     
> 	    /* FREQ2 = aux/2 = 48 MHz */
> 	    sys_freqctrl |= ((0<<22) | (1<<21) | (1<<20));
> 	    au_writel(sys_freqctrl, SYS_FREQCTRL0);
>     
> 	    /* Route 48MHz FREQ2 into USBH/USBD/IrDA */
> 	    sys_clksrc |= ((4<<2) | (0<<1) | 0 );
> 	    au_writel(sys_clksrc, SYS_CLKSRC);
>     
> 	    /* setup the static bus controller */
> 	    au_writel(0x00000002, MEM_STCFG3);  /* type = PCMCIA */
> 	    au_writel(0x280E3D07, MEM_STTIME3); /* 250ns cycle time */
> 	    au_writel(0x10000000, MEM_STADDR3); /* any PCMCIA select */
>     
> 	    /* Get USB Functionality pin state (device vs host drive pins) */
> 	    pin_func = au_readl(SYS_PINFUNC) & (u32)(~0x8000);
>     #ifndef CONFIG_AU1X00_USB_DEVICE
> 	    /* 2nd USB port is USB host */
> 	    pin_func |= 0x8000;
>     #endif
> 	    au_writel(pin_func, SYS_PINFUNC);
>     #endif /* defined (CONFIG_USB_OHCI_HCD) || defined (CONFIG_AU1X00_USB_DEVICE) */
> 
> But don't you think is better to put this code into USB driver (file
> ohci-au1xxx.c) during probing stage? In this manner each platforms may
> don't worry about clock initialization...

Seems too board specific since the clocks can be routed differently on
each board. 

Pete