* RE: Is it any serial8250 platform driver available?
@ 2010-10-25 15:37 ` Ardelean, Andrei
0 siblings, 0 replies; 7+ messages in thread
From: Ardelean, Andrei @ 2010-10-25 15:37 UTC (permalink / raw)
To: David Daney; +Cc: linux-mips
Hi David,
I studied this driver and few other examples and I have one question
regarding the driver configuration:
Which field must be initialized in the plat_serial8250_port structure:
unsigned long iobase; /* io base address */
void __iomem *membase; /* ioremap cookie or NULL */
resource_size_t mapbase; /* resource base */
Some drivers init only one of them, other two fields.
My UART is located at 0x1bf01000, can I put this value in all those
fields?
Thanks,
Andrei
-----Original Message-----
From: David Daney [mailto:ddaney@caviumnetworks.com]
Sent: Friday, October 22, 2010 3:31 PM
To: Ardelean, Andrei
Cc: linux-mips@linux-mips.org
Subject: Re: Is it any serial8250 platform driver available?
On 10/22/2010 12:23 PM, Ardelean, Andrei wrote:
> Hi,
>
> I am porting MIPS Linux from MALTA to a new board. I ported early
> console code from malta_console.c and I am looking now to use a
> interrupt driven driver for TTY. My UART is compatible with 8250 (1
UART
> port only) but the UART registers are directly mapped in CPU memory
map.
> There is no PCI bus. My problem is that the driver implemented in
8250.c
> is very complex and it seems to be hardcode for ISA bus, is it any
> simple platform UART driver available to be directly mapped in the CPU
> space? Can you give me some advice what would be a good approach for
my
> case?
>
Many chips have 8250 compatible ports and use 8250.c.
See arch/mips/cavium-octeon/serial.c
David Daeny
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: Is it any serial8250 platform driver available?
2010-10-25 15:37 ` Ardelean, Andrei
(?)
@ 2010-10-25 14:53 ` Sergei Shtylyov
-1 siblings, 0 replies; 7+ messages in thread
From: Sergei Shtylyov @ 2010-10-25 14:53 UTC (permalink / raw)
To: Ardelean, Andrei; +Cc: David Daney, linux-mips
Hello.
[Resending to the list as I've only replied to Andrei -- due to stupid keyboard
layout switcher in OpenSUSE preventing Ctrl-Shift-R in Thunderbird from
working... :-/]
On 25-10-2010 19:37, Ardelean, Andrei wrote:
> Hi David,
> I studied this driver and few other examples and I have one question
> regarding the driver configuration:
> Which field must be initialized in the plat_serial8250_port structure:
> unsigned long iobase; /* io base address */
> void __iomem *membase; /* ioremap cookie or NULL */
> resource_size_t mapbase; /* resource base */
> Some drivers init only one of them, other two fields.
Of course, .iobase is for I/O port mapped UARTs (think PC), .mapbase and
.membase are for the memory mapped UARTs (like your case).
> My UART is located at 0x1bf01000, can I put this value in all those
> fields?
You only need to put that into ,mapbase.
> Thanks,
> Andrei
WBR, Sergei
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: Is it any serial8250 platform driver available?
2010-10-25 15:37 ` Ardelean, Andrei
(?)
(?)
@ 2010-10-25 16:43 ` David Daney
-1 siblings, 0 replies; 7+ messages in thread
From: David Daney @ 2010-10-25 16:43 UTC (permalink / raw)
To: Ardelean, Andrei; +Cc: linux-mips
On 10/25/2010 08:37 AM, Ardelean, Andrei wrote:
> Hi David,
>
> I studied this driver and few other examples and I have one question
> regarding the driver configuration:
> Which field must be initialized in the plat_serial8250_port structure:
> unsigned long iobase; /* io base address */
> void __iomem *membase; /* ioremap cookie or NULL */
> resource_size_t mapbase; /* resource base */
> Some drivers init only one of them, other two fields.
>
> My UART is located at 0x1bf01000, can I put this value in all those
> fields?
>
As with many things in life, it depends.
In this case it depends on the flags you pass as well as any serial_in()
and serial_out() functions you may have. It is fortunate you have the
source code available, you can use it to see how the different options
affect things.
David Daney
> Thanks,
> Andrei
>
>
> -----Original Message-----
> From: David Daney [mailto:ddaney@caviumnetworks.com]
> Sent: Friday, October 22, 2010 3:31 PM
> To: Ardelean, Andrei
> Cc: linux-mips@linux-mips.org
> Subject: Re: Is it any serial8250 platform driver available?
>
> On 10/22/2010 12:23 PM, Ardelean, Andrei wrote:
>> Hi,
>>
>> I am porting MIPS Linux from MALTA to a new board. I ported early
>> console code from malta_console.c and I am looking now to use a
>> interrupt driven driver for TTY. My UART is compatible with 8250 (1
> UART
>> port only) but the UART registers are directly mapped in CPU memory
> map.
>> There is no PCI bus. My problem is that the driver implemented in
> 8250.c
>> is very complex and it seems to be hardcode for ISA bus, is it any
>> simple platform UART driver available to be directly mapped in the CPU
>> space? Can you give me some advice what would be a good approach for
> my
>> case?
>>
>
> Many chips have 8250 compatible ports and use 8250.c.
>
> See arch/mips/cavium-octeon/serial.c
>
> David Daeny
>
^ permalink raw reply [flat|nested] 7+ messages in thread