Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8

Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8

[Angelo Butti]

Hi all,
my name is Angelo and I have a problem with some Pericom Serial boards.
This hardware is compatible to 16C550 but is not working good.

Now I can workaround the problem, I understand it but I'm not able to make some
patch for the serial driver inside the linux kernel. So, now I want
try to explain the
problems and if you can adjust the driver also for this device will be
great; or if you can
explain me with some example how I can do it and send to you the patch .....

Anyway, the problem is related to Pericom serial boards, pci-id:
12d8:7952 (2 serials)
12d8:7954 (4 serials)
12d8:7958 (8 serials)

The first problem is related to the kind of the serial ports. This
hardware can be
232-422-4852W-4854W mode, and must be set inside the PCI express
registers at the offset b4h.
For example if you have a 2 serial port 485-2W board, before use it
you must set that
register to 0xFF ( I make this with setpci command and all is ok)

Te second problem, more critical for me, is the bps setting. The board
that I want use have
on board a 14.7456 Mhz, and there are a table inside datasheet with
the configuration example
and the formula to set proper bps settings. The problem is related to
the standard linux driver that use the clock equal to  1.8432 MHz.
So every time that I open the serial, this bps isn't correct. I must
adjust it writing inside the registers (after open) to fix the
problem.
Is possible add this kind of board inside the standard linux driver to
have a good bps setting ?

En example, to set 115200bps:
Standard linux driver: DLL:0x1 DLH:0x0
Pericom formula: DLL:0x8 DLH:0x0

(Ref. PI7C9X7952/4/8 (Datasheet))

Thanks, best regards
Angelo

Re: Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8

[Angelo Butti]

Hi all,
I'm here again to try to solve and add support to Pericom serial devices.

To solve is really simple, but I don't know if I make the correct
procedure. The solution is change the clock value from 1.8432 to
14.7456.
To do this I add a new setup specific for pericom devices, and I add
this 3 devices inside the Master list of serial port.

Now, is possible add this to the standard linux kernel, so also the
Pericom device will be ok ?

Below the patch for the 3.10.11 kernel ....

1311,1333d1310
< static int pci_pericom_setup(struct serial_private *priv,
<  const struct pciserial_board *board,
<  struct uart_8250_port *port, int idx)
< {
< unsigned int bar, offset = board->first_offset, maxnr;
<
< bar = FL_GET_BASE(board->flags);
< if (board->flags & FL_BASE_BARS)
< bar += idx;
< else
< offset += idx * board->uart_offset;
<
< maxnr = (pci_resource_len(priv->dev, bar) - board->first_offset) >>
< (board->reg_shift + 3);
<
< if (board->flags & FL_REGION_SZ_CAP && idx >= maxnr)
< return 1;
<
< port->port.uartclk = 14745600;
<
< return setup_port(priv, port, bar, offset, board->reg_shift);
< }
<
1850,1874d1826
< /*
< * Pericom
< */
< {
< .vendor = 0x12d8,
< .device = 0x7952,
< .subvendor = PCI_ANY_ID,
< .subdevice = PCI_ANY_ID,
< .setup = pci_pericom_setup,
< },
< {
< .vendor = 0x12d8,
< .device = 0x7954,
< .subvendor = PCI_ANY_ID,
< .subdevice = PCI_ANY_ID,
< .setup = pci_pericom_setup,
< },
< {
< .vendor = 0x12d8,
< .device = 0x7958,
< .subvendor = PCI_ANY_ID,
< .subdevice = PCI_ANY_ID,
< .setup = pci_pericom_setup,
< },
<

Regards,
Angelo

2013/6/26 Angelo Butti <buttiangelo@alice.it>:
> Hi all,
> my name is Angelo and I have a problem with some Pericom Serial boards.
> This hardware is compatible to 16C550 but is not working good.
>
> Now I can workaround the problem, I understand it but I'm not able to make some
> patch for the serial driver inside the linux kernel. So, now I want
> try to explain the
> problems and if you can adjust the driver also for this device will be
> great; or if you can
> explain me with some example how I can do it and send to you the patch .....
>
> Anyway, the problem is related to Pericom serial boards, pci-id:
> 12d8:7952 (2 serials)
> 12d8:7954 (4 serials)
> 12d8:7958 (8 serials)
>
> The first problem is related to the kind of the serial ports. This
> hardware can be
> 232-422-4852W-4854W mode, and must be set inside the PCI express
> registers at the offset b4h.
> For example if you have a 2 serial port 485-2W board, before use it
> you must set that
> register to 0xFF ( I make this with setpci command and all is ok)
>
> Te second problem, more critical for me, is the bps setting. The board
> that I want use have
> on board a 14.7456 Mhz, and there are a table inside datasheet with
> the configuration example
> and the formula to set proper bps settings. The problem is related to
> the standard linux driver that use the clock equal to  1.8432 MHz.
> So every time that I open the serial, this bps isn't correct. I must
> adjust it writing inside the registers (after open) to fix the
> problem.
> Is possible add this kind of board inside the standard linux driver to
> have a good bps setting ?
>
> En example, to set 115200bps:
> Standard linux driver: DLL:0x1 DLH:0x0
> Pericom formula: DLL:0x8 DLH:0x0
>
> (Ref. PI7C9X7952/4/8 (Datasheet))
>
> Thanks, best regards
> Angelo

Re: Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8

[Greg KH]

On Tue, Oct 15, 2013 at 03:48:55PM +0200, Angelo Butti wrote:
> Hi all,
> I'm here again to try to solve and add support to Pericom serial devices.
> 
> To solve is really simple, but I don't know if I make the correct
> procedure. The solution is change the clock value from 1.8432 to
> 14.7456.
> To do this I add a new setup specific for pericom devices, and I add
> this 3 devices inside the Master list of serial port.
> 
> Now, is possible add this to the standard linux kernel, so also the
> Pericom device will be ok ?
> 
> Below the patch for the 3.10.11 kernel ....

Can you generate the patch with 'diff -u' so that it is in a format that
I can apply it to the kernel tree?  Specifics on how to create the
patch, and what you need to include in it is in the
Documentation/SubmittingPatches file.

If you have any problems or questions after reading that file, please
let us know.

thanks,

greg k-h

Re: Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8

[Angelo Butti]

I'm really sorry for my mistake.
Also, maybe that there is a simple way to change the clock without
rewrite the standard serial setup procedure, but I cannot find it ....
Below the correct one:

--- linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c.orig
2013-09-16 20:13:52.918548000 +0300
+++ linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c
2013-10-15 16:20:18.566685996 +0300
@@ -1308,6 +1308,29 @@ static int pci_default_setup(struct seri
  return setup_port(priv, port, bar, offset, board->reg_shift);
 }

+static int pci_pericom_setup(struct serial_private *priv,
+  const struct pciserial_board *board,
+  struct uart_8250_port *port, int idx)
+{
+ unsigned int bar, offset = board->first_offset, maxnr;
+
+ bar = FL_GET_BASE(board->flags);
+ if (board->flags & FL_BASE_BARS)
+ bar += idx;
+ else
+ offset += idx * board->uart_offset;
+
+ maxnr = (pci_resource_len(priv->dev, bar) - board->first_offset) >>
+ (board->reg_shift + 3);
+
+ if (board->flags & FL_REGION_SZ_CAP && idx >= maxnr)
+ return 1;
+
+ port->port.uartclk = 14745600;
+
+ return setup_port(priv, port, bar, offset, board->reg_shift);
+}
+
 static int
 ce4100_serial_setup(struct serial_private *priv,
   const struct pciserial_board *board,
@@ -1825,6 +1848,31 @@ static struct pci_serial_quirk pci_seria
  .exit = pci_plx9050_exit,
  },
  /*
+ * Pericom
+ */
+ {
+ .vendor = 0x12d8,
+ .device = 0x7952,
+ .subvendor = PCI_ANY_ID,
+ .subdevice = PCI_ANY_ID,
+ .setup = pci_pericom_setup,
+ },
+ {
+ .vendor = 0x12d8,
+ .device = 0x7954,
+ .subvendor = PCI_ANY_ID,
+ .subdevice = PCI_ANY_ID,
+ .setup = pci_pericom_setup,
+ },
+ {
+ .vendor = 0x12d8,
+ .device = 0x7958,
+ .subvendor = PCI_ANY_ID,
+ .subdevice = PCI_ANY_ID,
+ .setup = pci_pericom_setup,
+ },
+
+ /*
  * PLX
  */
  {

2013/10/15 Greg KH <gregkh@linuxfoundation.org>:
> On Tue, Oct 15, 2013 at 03:48:55PM +0200, Angelo Butti wrote:
>> Hi all,
>> I'm here again to try to solve and add support to Pericom serial devices.
>>
>> To solve is really simple, but I don't know if I make the correct
>> procedure. The solution is change the clock value from 1.8432 to
>> 14.7456.
>> To do this I add a new setup specific for pericom devices, and I add
>> this 3 devices inside the Master list of serial port.
>>
>> Now, is possible add this to the standard linux kernel, so also the
>> Pericom device will be ok ?
>>
>> Below the patch for the 3.10.11 kernel ....
>
> Can you generate the patch with 'diff -u' so that it is in a format that
> I can apply it to the kernel tree?  Specifics on how to create the
> patch, and what you need to include in it is in the
> Documentation/SubmittingPatches file.
>
> If you have any problems or questions after reading that file, please
> let us know.
>
> thanks,
>
> greg k-h

Re: Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8

[Greg KH]

On Tue, Oct 15, 2013 at 07:20:18PM +0200, Angelo Butti wrote:
> I'm really sorry for my mistake.

No worries, but your email client turned all tabs into spaces, and made
the patch imposible to apply :(

> Also, maybe that there is a simple way to change the clock without
> rewrite the standard serial setup procedure, but I cannot find it ....
> Below the correct one:
> 
> --- linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c.orig
> 2013-09-16 20:13:52.918548000 +0300
> +++ linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c
> 2013-10-15 16:20:18.566685996 +0300
> @@ -1308,6 +1308,29 @@ static int pci_default_setup(struct seri
>   return setup_port(priv, port, bar, offset, board->reg_shift);
>  }
> 
> +static int pci_pericom_setup(struct serial_private *priv,
> +  const struct pciserial_board *board,
> +  struct uart_8250_port *port, int idx)

See?

Also, we need a "Signed-off-by:" line as per the instructions in the
Documentation/SubmittingPatches file (take a look at it for what that
means.)

Care to try again?

thanks,

greg k-h

Re: Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8

[Angelo Butti]

On 10/15/2013 08:28 PM, Greg KH wrote:
> On Tue, Oct 15, 2013 at 07:20:18PM +0200, Angelo Butti wrote:
>> I'm really sorry for my mistake.
>
> No worries, but your email client turned all tabs into spaces, and made
> the patch imposible to apply :(
>
>> Also, maybe that there is a simple way to change the clock without
>> rewrite the standard serial setup procedure, but I cannot find it ....
>> Below the correct one:
>>
>> --- linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c.orig
>> 2013-09-16 20:13:52.918548000 +0300
>> +++ linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c
>> 2013-10-15 16:20:18.566685996 +0300
>> @@ -1308,6 +1308,29 @@ static int pci_default_setup(struct seri
>>    return setup_port(priv, port, bar, offset, board->reg_shift);
>>   }
>>
>> +static int pci_pericom_setup(struct serial_private *priv,
>> +  const struct pciserial_board *board,
>> +  struct uart_8250_port *port, int idx)
>
> See?
>
> Also, we need a "Signed-off-by:" line as per the instructions in the
> Documentation/SubmittingPatches file (take a look at it for what that
> means.)
>
> Care to try again?
>
> thanks,
>
> greg k-h
>

Ok, I change the email client .... I hope ....

Signed-off-by: Angelo Butti <buttiangelo@gmail.com>

Regards,
Angelo


--- linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c.orig 
2013-09-16 20:13:52.918548000 +0300
+++ linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c 
2013-10-15 16:20:18.566685996 +0300
@@ -1308,6 +1308,29 @@ static int pci_default_setup(struct seri
  	return setup_port(priv, port, bar, offset, board->reg_shift);
  }

+static int pci_pericom_setup(struct serial_private *priv,
+		  const struct pciserial_board *board,
+		  struct uart_8250_port *port, int idx)
+{
+	unsigned int bar, offset = board->first_offset, maxnr;
+
+	bar = FL_GET_BASE(board->flags);
+	if (board->flags & FL_BASE_BARS)
+		bar += idx;
+	else
+		offset += idx * board->uart_offset;
+
+	maxnr = (pci_resource_len(priv->dev, bar) - board->first_offset) >>
+		(board->reg_shift + 3);
+
+	if (board->flags & FL_REGION_SZ_CAP && idx >= maxnr)
+		return 1;
+
+	port->port.uartclk = 14745600;
+
+	return setup_port(priv, port, bar, offset, board->reg_shift);
+}
+
  static int
  ce4100_serial_setup(struct serial_private *priv,
  		  const struct pciserial_board *board,
@@ -1825,6 +1848,31 @@ static struct pci_serial_quirk pci_seria
  		.exit		= pci_plx9050_exit,
  	},
  	/*
+	 * Pericom
+	 */
+	{
+		.vendor		= 0x12d8,
+		.device		= 0x7952,
+		.subvendor	= PCI_ANY_ID,
+		.subdevice	= PCI_ANY_ID,
+		.setup		= pci_pericom_setup,
+	},		
+	{
+		.vendor		= 0x12d8,
+		.device		= 0x7954,
+		.subvendor	= PCI_ANY_ID,
+		.subdevice	= PCI_ANY_ID,
+		.setup		= pci_pericom_setup,
+	},		
+	{
+		.vendor		= 0x12d8,
+		.device		= 0x7958,
+		.subvendor	= PCI_ANY_ID,
+		.subdevice	= PCI_ANY_ID,
+		.setup		= pci_pericom_setup,
+	},		
+
+	/*
  	 * PLX
  	 */
  	{

Re: Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8

[Greg KH]

On Tue, Oct 15, 2013 at 10:41:10PM +0300, Angelo Butti wrote:
> On 10/15/2013 08:28 PM, Greg KH wrote:
> > On Tue, Oct 15, 2013 at 07:20:18PM +0200, Angelo Butti wrote:
> >> I'm really sorry for my mistake.
> >
> > No worries, but your email client turned all tabs into spaces, and made
> > the patch imposible to apply :(
> >
> >> Also, maybe that there is a simple way to change the clock without
> >> rewrite the standard serial setup procedure, but I cannot find it ....
> >> Below the correct one:
> >>
> >> --- linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c.orig
> >> 2013-09-16 20:13:52.918548000 +0300
> >> +++ linux-3.10.11-200.fc19.i686/drivers/tty/serial/8250/8250_pci.c
> >> 2013-10-15 16:20:18.566685996 +0300
> >> @@ -1308,6 +1308,29 @@ static int pci_default_setup(struct seri
> >>    return setup_port(priv, port, bar, offset, board->reg_shift);
> >>   }
> >>
> >> +static int pci_pericom_setup(struct serial_private *priv,
> >> +  const struct pciserial_board *board,
> >> +  struct uart_8250_port *port, int idx)
> >
> > See?
> >
> > Also, we need a "Signed-off-by:" line as per the instructions in the
> > Documentation/SubmittingPatches file (take a look at it for what that
> > means.)
> >
> > Care to try again?
> >
> > thanks,
> >
> > greg k-h
> >
> 
> Ok, I change the email client .... I hope ....

The patch was a bit whitespace dammaged, but I fixed it up by hand and
applied it.

thanks,

greg k-h