[U-Boot] [PATCH 1/1] igep0020: set OMAP MUX mcspi1_cs2 pin to GPIO 176 mode

[Enric Balletbò i Serra]

Hi Javier,

2012/7/3 Javier Martinez Canillas <javier at dowhile0.org>

> According to the IGEPv2 Rev.C data-sheet the LAN9221i pin 14 (IRQ) is
> connected to the OMAP3730 mcspi1_cs2 pin. Since this omap mux pin acts
> as an IRQ line, it has to be configured as an input GPIO.
>
> IGEPv2 platform code sets the smsc911x_cfg->gpio_irq to GPIO 176 but
> since the mux pin default mode is MODE7 (safe_mode) the driver fails
> when trying to register the IRQ:
>
> [    1.994598] smsc911x: Driver version 2008-10-21
> [    3.704162] irq 272: nobody cared (try booting with the "irqpoll"
> option)
> [    3.711364] [<c001a114>] (unwind_backtrace+0x0/0xf0) from [<c009a0d4>]
> (__report_bad_irq+0x20/0xbc)
> [    3.720916] [<c009a0d4>] (__report_bad_irq+0x20/0xbc) from [<c009a41c>]
> (note_interrupt+0x1d8/0x238)
> [    3.730560] [<c009a41c>] (note_interrupt+0x1d8/0x238) from [<c0098234>]
> (handle_irq_event_percpu+0xc0/0x260)
> [    3.740936] [<c0098234>] (handle_irq_event_percpu+0xc0/0x260) from
> [<c0098410>] (handle_irq_event+0x3c/0x5c)
> [    3.751312] [<c0098410>] (handle_irq_event+0x3c/0x5c) from [<c009abe0>]
> (handle_level_irq+0xac/0x10c)
> [    3.761047] [<c009abe0>] (handle_level_irq+0xac/0x10c) from
> [<c0097a34>] (generic_handle_irq+0x30/0x48)
> [    3.770935] [<c0097a34>] (generic_handle_irq+0x30/0x48) from
> [<c02a6b74>] (gpio_irq_handler+0x180/0x1d4)
> [    3.780944] [<c02a6b74>] (gpio_irq_handler+0x180/0x1d4) from
> [<c0097a34>] (generic_handle_irq+0x30/0x48)
> [    3.790954] [<c0097a34>] (generic_handle_irq+0x30/0x48) from
> [<c0013e18>] (handle_IRQ+0x4c/0xac)
> [    3.800231] [<c0013e18>] (handle_IRQ+0x4c/0xac) from [<c000858c>]
> (omap3_intc_handle_irq+0x60/0x74)
> [    3.809783] [<c000858c>] (omap3_intc_handle_irq+0x60/0x74) from
> [<c04979e4>] (__irq_svc+0x44/0x60)
> [    3.819213] Exception stack(0xee42fde0 to 0xee42fe28)
> [    3.824554] fde0: 00000001 00000001 00000000 00000000 60000013 c06cce14
> c06cce14 00000110
> [    3.833190] fe00: 00000000 c06ccdf4 60000013 ee41d000 fb058064 ee42fe28
> c0089e08 c04976b4
> [    3.841796] fe20: 20000013 ffffffff
> [    3.845489] [<c04979e4>] (__irq_svc+0x44/0x60) from [<c04976b4>]
> (_raw_spin_unlock_irqrestore+0x34/0x44)
> [    3.855499] [<c04976b4>] (_raw_spin_unlock_irqrestore+0x34/0x44) from
> [<c0099744>] (__setup_irq+0x1b8/0x3f0)
> [    3.865875] [<c0099744>] (__setup_irq+0x1b8/0x3f0) from [<c0099a34>]
> (request_threaded_irq+0xb8/0x140)
> [    3.875701] [<c0099a34>] (request_threaded_irq+0xb8/0x140) from
> [<c0487950>] (smsc911x_drv_probe+0x75c/0x11a4)
> [    3.886260] [<c0487950>] (smsc911x_drv_probe+0x75c/0x11a4) from
> [<c02e9bcc>] (platform_drv_probe+0x18/0x1c)
> [    3.896545] [<c02e9bcc>] (platform_drv_probe+0x18/0x1c) from
> [<c02e89b8>] (driver_probe_device+0x90/0x210)
> [    3.906707] [<c02e89b8>] (driver_probe_device+0x90/0x210) from
> [<c02e8bcc>] (__driver_attach+0x94/0x98)
> [    3.916625] [<c02e8bcc>] (__driver_attach+0x94/0x98) from [<c02e7298>]
> (bus_for_each_dev+0x50/0x7c)
> [    3.926177] [<c02e7298>] (bus_for_each_dev+0x50/0x7c) from [<c02e81d4>]
> (bus_add_driver+0x184/0x248)
> [    3.935821] [<c02e81d4>] (bus_add_driver+0x184/0x248) from [<c02e909c>]
> (driver_register+0x78/0x12c)
> [    3.945465] [<c02e909c>] (driver_register+0x78/0x12c) from [<c0008648>]
> (do_one_initcall+0x34/0x178)
> [    3.955108] [<c0008648>] (do_one_initcall+0x34/0x178) from [<c066e8f4>]
> (kernel_init+0xfc/0x1c0)
> [    3.964385] [<c066e8f4>] (kernel_init+0xfc/0x1c0) from [<c00140b0>]
> (kernel_thread_exit+0x0/0x8)
> [    3.973632] handlers:
> [    3.976043] [<c034e2cc>] smsc911x_irqhandler
> [    3.980560] Disabling IRQ #272
>
> Signed-off-by: Javier Martinez Canillas <javier at dowhile0.org>
> ---
>  board/isee/igep0020/igep0020.h |    3 ++-
>  1 files changed, 2 insertions(+), 1 deletions(-)
>
> diff --git a/board/isee/igep0020/igep0020.h
> b/board/isee/igep0020/igep0020.h
> index 3d6e15f..eb1aa30 100644
> --- a/board/isee/igep0020/igep0020.h
> +++ b/board/isee/igep0020/igep0020.h
> @@ -143,5 +143,6 @@ static void setup_net_chip(void);
>         MUX_VAL(CP(SYS_BOOT5),      (IEN  | PTD | DIS | M4)) /* GPIO_7 */\
>         MUX_VAL(CP(SYS_BOOT6),      (IEN  | PTD | DIS | M4)) /* GPIO_8 */\
>         MUX_VAL(CP(SDRC_CKE0),      (IDIS | PTU | EN  | M0)) /* SDRC_CKE0
> */\
> -       MUX_VAL(CP(SDRC_CKE1),      (IDIS | PTU | EN  | M0)) /* SDRC_CKE1
> */
> +       MUX_VAL(CP(SDRC_CKE1),      (IDIS | PTU | EN  | M0)) /* SDRC_CKE1
> */\
> +       MUX_VAL(CP(MCSPI1_CS2),     (IEN  | PTD | DIS | M4)) /*
> GPIO_176-ETH IRQ */
>  #endif
> --
> 1.7.7.6
>
>
I'm not sure if this is the correct place to do this.

This was discussed for a long, the main question is who must set the pin
muxer ?

In my opinion u-boot only should set mux for the pins that it is using and
I think u-boot is not using this IRQ pin for ethernet driver (not sure, I
need to check). At kernel level of course the driver uses this pin. In my
opinion the kernel should guarantees that this pin is muxed correctly, not
u-boot.

Any other opinion ? How this is solved in others boards ?

Cheers,
  Enric