diff mbox

tty: serial: omap: increase max consoles to 10

Message ID 1413908616-843-1-git-send-email-nm@ti.com
State New
Headers show

Commit Message

Nishanth Menon Oct. 21, 2014, 4:23 p.m. UTC
Increase the maximum number of consoles possible to 10 since DRA7 now
has the maximum number of consoles possible. without doing this, for
example, enabling DRA7 UART10 results in internal data structures and
console cannot match up and we endup with a crash as follows:

[    1.903503] omap_uart 48424000.serial: [UART-1]: failure [serial_omap_probe]: -22
[    1.911437] omap_uart: probe of 48424000.serial failed with error -22
[    1.920379] Unable to handle kernel NULL pointer dereference at virtual address 00000004
[    1.928894] pgd = c0004000
[    1.931732] [00000004] *pgd=00000000
[    1.935485] Internal error: Oops: 5 [#1] SMP ARM
[    1.940338] Modules linked in:
[    1.943542] CPU: 1 PID: 12 Comm: kworker/1:0 Tainted: G        W      3.18.0-rc1-00001-g8821bc4-dirty #6
[    1.953521] task: ed8a2d00 ti: ed8a4000 task.ti: ed8a4000
[    1.959197] PC is at process_one_work+0x38/0x4a4
[    1.964050] LR is at 0x0
[    1.966705] pc : [<c00548e0>]    lr : [<00000000>]    psr: 40000093
[    1.966705] sp : ed8a5ea8  ip : ed8a5ec8  fp : eeb9abc0
[    1.978759] r10: ed8a4000  r9 : 00000008  r8 : ed842458
[    1.984252] r7 : 00000000  r6 : eeb9abc0  r5 : ed842440  r4 : edbf26a8
[    1.991119] r3 : 00000000  r2 : 00000000  r1 : 00000000  r0 : 00000000
[    1.997985] Flags: nZcv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
[    2.005767] Control: 10c5387d  Table: 8000406a  DAC: 00000015
[    2.011810] Process kworker/1:0 (pid: 12, stack limit = 0xed8a4248)
[    2.018371] Stack: (0xed8a5ea8 to 0xed8a6000)
[    2.022949] 5ea0:                   00000001 00000000 60000093 c008346c 00000001 ed8a5ec8
[    2.031555] 5ec0: c0054de4 eeb9abc0 ed8a4000 ed842458 00000008 ed8a4000 eeb9abc0 ed842440
[    2.040161] 5ee0: eeb9abc0 eeb9abf0 ed8a4000 ed842458 00000008 ed8a4000 eeb9abc0 c0054ec4
[    2.048767] 5f00: ed8a4000 eeb9ac4c a0000053 00000000 ed845bc0 ed842440 c0054d80 00000000
[    2.057342] 5f20: 00000000 00000000 00000000 c005999c 00000001 00000000 c05eaa64 ed842440
[    2.065948] 5f40: 00000000 00000000 dead4ead ffffffff ffffffff c097c680 00000000 00000000
[    2.074554] 5f60: c078acd4 ed8a5f64 ed8a5f64 00000000 00000000 dead4ead ffffffff ffffffff
[    2.083160] 5f80: c097c680 00000000 00000000 c078acd4 ed8a5f90 ed8a5f90 600000d3 ed845bc0
[    2.091766] 5fa0: c00598d4 00000000 00000000 c000e668 00000000 00000000 00000000 00000000
[    2.100341] 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    2.108947] 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 90005148 11010482
[    2.117553] [<c00548e0>] (process_one_work) from [<c0054ec4>] (worker_thread+0x144/0x498)
[    2.126159] [<c0054ec4>] (worker_thread) from [<c005999c>] (kthread+0xc8/0xe4)
[    2.133758] [<c005999c>] (kthread) from [<c000e668>] (ret_from_fork+0x14/0x2c)
[    2.141357] Code: e1a04001 e1a05000 e893000f e31e0004 (e5978004)
[    2.147766] ---[ end trace 5798e2803311b69f ]---
<snip>

The final solution is to transition off to use 8250 driver and no
dependency on console structures and move away from omap-serial driver,
hence no major cleanups are done for this driver.

Signed-off-by: Nishanth Menon <nm@ti.com>
---

Ref: eventual 8250 driver to transition to: http://marc.info/?l=linux-kernel&m=141201409108078&w=2

 drivers/tty/serial/omap-serial.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Sebastian Andrzej Siewior Oct. 22, 2014, 8:03 a.m. UTC | #1
On 10/21/2014 06:23 PM, Nishanth Menon wrote:
> 
> The final solution is to transition off to use 8250 driver and no
> dependency on console structures and move away from omap-serial driver,
> hence no major cleanups are done for this driver.

So the shiny new driver works for you, is this what you are saying?

> diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
> index 18c30ca..4f9cbb6 100644
> --- a/drivers/tty/serial/omap-serial.c
> +++ b/drivers/tty/serial/omap-serial.c
> @@ -46,7 +46,7 @@
>  
>  #include <dt-bindings/gpio/gpio.h>
>  
> -#define OMAP_MAX_HSUART_PORTS	6
> +#define OMAP_MAX_HSUART_PORTS	10
>  
>  #define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))

Please also add a check in the probe code that "up->port.line" does not
exceed OMAP_MAX_HSUART_PORTS again. So we leave the probe function with
an error code instead.

Sebastian
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Nishanth Menon Oct. 22, 2014, 12:24 p.m. UTC | #2
On 10:03-20141022, Sebastian Andrzej Siewior wrote:
> On 10/21/2014 06:23 PM, Nishanth Menon wrote:
> > 
> > The final solution is to transition off to use 8250 driver and no
> > dependency on console structures and move away from omap-serial driver,
> > hence no major cleanups are done for this driver.
> 
> So the shiny new driver works for you, is this what you are saying?

We have to complete our transition over to the new driver to see if we
have any behavior change. We will eventually get there.

> 
> > diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
> > index 18c30ca..4f9cbb6 100644
> > --- a/drivers/tty/serial/omap-serial.c
> > +++ b/drivers/tty/serial/omap-serial.c
> > @@ -46,7 +46,7 @@
> >  
> >  #include <dt-bindings/gpio/gpio.h>
> >  
> > -#define OMAP_MAX_HSUART_PORTS	6
> > +#define OMAP_MAX_HSUART_PORTS	10
> >  
> >  #define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
> 
> Please also add a check in the probe code that "up->port.line" does not
> exceed OMAP_MAX_HSUART_PORTS again. So we leave the probe function with
> an error code instead.

Thanks. yeah - that is a pretty good idea. Will do the same for v2.
diff mbox

Patch

diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 18c30ca..4f9cbb6 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -46,7 +46,7 @@ 
 
 #include <dt-bindings/gpio/gpio.h>
 
-#define OMAP_MAX_HSUART_PORTS	6
+#define OMAP_MAX_HSUART_PORTS	10
 
 #define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))