[RFC PATCH 04/11] OMAP: Add early device for system control module

[Valentin, Eduardo]

Hello,

On Fri, May 25, 2012 at 2:32 PM, Konstantin Baydarov
<kbaidarov at dev.rtsoft.ru> wrote:
>  Hi , Eduardo.
>
> On 05/25/2012 12:25 PM, Eduardo Valentin wrote:
>> This is a way to add an early device for system control module.
>> the code is also requesting for driver registration and probing.
>> Done at early_initcall because at that time, ioremapping is possible.

OK. Which debug config you have?

In any case, that can be solved by not requesting the resource and
passing the address area by other means.

>>
>> Signed-off-by: Eduardo Valentin <eduardo.valentin at ti.com>
>> ---
>>  arch/arm/mach-omap2/devices.c |   29 +++++++++++++++++++++++++++++
>>  1 files changed, 29 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/arm/mach-omap2/devices.c b/arch/arm/mach-omap2/devices.c
>> index 9332673..58cc5c3 100644
>> --- a/arch/arm/mach-omap2/devices.c
>> +++ b/arch/arm/mach-omap2/devices.c
>> @@ -40,6 +40,35 @@
>>  #define L3_MODULES_MAX_LEN 12
>>  #define L3_MODULES 3
>>
>> +static struct resource control_resources[] = {
>> +     [0] = {
>> +             .start  = 0x4a002000,
>> +             .end    = 0x4a0027ff,
>> +             .flags  = IORESOURCE_MEM,
>> +     },
>> +};
>> +static struct platform_device control_device = {
>> +     .name           = "omap-control-core",
>> +     .id             = 0,
>> +     .resource       = control_resources,
>> +     .num_resources  = ARRAY_SIZE(control_resources),
>> +};
>> +
>> +static struct platform_device *early_devices[] __initdata = {
>> +     &control_device,
>> +};
>> +
>> +static int __init plat_early_device_setup(void)
>> +{
>> +     early_platform_add_devices(early_devices,
>> +                                ARRAY_SIZE(early_devices));
>> +     early_platform_driver_register_all("early_omap_control");
>> +     early_platform_driver_probe("early_omap_control", 1, false);
> I checked out git://gitorious.org/omap-thermal/omap-thermal.git omap_scm_dev.
> Looks like that calling devm_kzalloc() and platform_get_resource() from early_initcall is too early.
> I get following backtrace (probably the backtrace is kernel config dependent):
> ...
> [    0.198455] [<c00193b4>] (unwind_backtrace+0x0/0xe0) from [<c02b2a10>] (do_raw_spin_lock+0x20/0x134)
> [    0.207977] [<c02b2a10>] (do_raw_spin_lock+0x20/0x134) from [<c05df068>] (_raw_spin_lock_irqsave+0x58/0x64)
> [    0.218109] [<c05df068>] (_raw_spin_lock_irqsave+0x58/0x64) from [<c02f03bc>] (devres_add+0x18/0x38)
> [    0.227600] [<c02f03bc>] (devres_add+0x18/0x38) from [<c02f07d0>] (devm_kzalloc+0x50/0x5c)
> [    0.236206] [<c02f07d0>] (devm_kzalloc+0x50/0x5c) from [<c05c73a4>] (omap_control_probe+0x20/0xe4)
> [    0.245544] [<c05c73a4>] (omap_control_probe+0x20/0xe4) from [<c07b3178>] (early_platform_driver_probe+0x1ac/0x23c)
> [    0.256378] [<c07b3178>] (early_platform_driver_probe+0x1ac/0x23c) from [<c0798030>] (plat_early_device_setup+0x2c/0x3c)
> [    0.267700] [<c0798030>] (plat_early_device_setup+0x2c/0x3c) from [<c078f8c4>] (do_one_initcall+0x90/0x164)
> [    0.277801] [<c078f8c4>] (do_one_initcall+0x90/0x164) from [<c078f9ec>] (kernel_init+0x54/0x1a4)
> [    0.286956] [<c078f9ec>] (kernel_init+0x54/0x1a4) from [<c0013818>] (kernel_thread_exit+0x0/0x8)
> [    0.296203] ------------[ cut here ]------------
> [    0.301086] WARNING: at include/linux/kref.h:41 kobject_get+0x24/0x48()
> [    0.308044] [<c00193b4>] (unwind_backtrace+0x0/0xe0) from [<c00394a4>] (warn_slowpath_common+0x48/0x60)
> [    0.317871] [<c00394a4>] (warn_slowpath_common+0x48/0x60) from [<c0039574>] (warn_slowpath_null+0x18/0x1c)
> [    0.327941] [<c0039574>] (warn_slowpath_null+0x18/0x1c) from [<c02a59b4>] (kobject_get+0x24/0x48)
> [    0.337219] [<c02a59b4>] (kobject_get+0x24/0x48) from [<c02eb588>] (get_device+0x14/0x1c)
> [    0.345764] [<c02eb588>] (get_device+0x14/0x1c) from [<c02eb66c>] (device_add+0xc4/0x594)
> [    0.354370] [<c02eb66c>] (device_add+0xc4/0x594) from [<c03eeab4>] (of_platform_device_create_pdata+0x5c/0x7c)
> [    0.364807] [<c03eeab4>] (of_platform_device_create_pdata+0x5c/0x7c) from [<c03eec94>] (of_platform_bus_create+0x1c0/0x258)
> [    0.376403] [<c03eec94>] (of_platform_bus_create+0x1c0/0x258) from [<c03eee4c>] (of_platform_populate+0x5c/0x88)
> [    0.387023] [<c03eee4c>] (of_platform_populate+0x5c/0x88) from [<c07b3178>] (early_platform_driver_probe+0x1ac/0x23c)
> [    0.398101] [<c07b3178>] (early_platform_driver_probe+0x1ac/0x23c) from [<c0798030>] (plat_early_device_setup+0x2c/0x3c)
> [    0.409423] [<c0798030>] (plat_early_device_setup+0x2c/0x3c) from [<c078f8c4>] (do_one_initcall+0x90/0x164)
> [    0.419586] [<c078f8c4>] (do_one_initcall+0x90/0x164) from [<c078f9ec>] (kernel_init+0x54/0x1a4)
> [    0.428771] [<c078f9ec>] (kernel_init+0x54/0x1a4) from [<c0013818>] (kernel_thread_exit+0x0/0x8)
> [    0.437957] ---[ end trace da227214a82491b7 ]--
> ...
>
>  BR,
>    Konstantin Baydarov.
>
>> +
>> +     return 0;
>> +}
>> +early_initcall(plat_early_device_setup);
>> +
>>  static int omap_init_control(void)
>>  {
>>       struct omap_hwmod               *oh;
>



-- 

Eduardo Valentin