[PATCH 2/5] drivers/bus: arm-cci: Add common control interface for ACE ports

[Abhilash Kesavan]

Hi Nicolas,

On Fri, Apr 11, 2014 at 11:54 PM, Nicolas Pitre
<nicolas.pitre at linaro.org> wrote:
> On Fri, 11 Apr 2014, Abhilash Kesavan wrote:
>
>> From: Andrew Bresticker <abrestic at chromium.org>
>>
>> cci_disable_port_by_cpu() can be used to disable an arbitrary
>> ACE port, but there is no C-callable way to enable an ACE port.
>> Change cci_disable_port_by_cpu() to cci_control_port_by_cpu()
>> to allow us to disable and enable a CPU's ACE port.
>>
>> Signed-off-by: Andrew Bresticker <abrestic at chromium.org>
>> Signed-off-by: Abhilash Kesavan <a.kesavan at samsung.com>
>
> As soon as this patch is applied, it'll break compilation for
> arch/arm/mach-vexpress/dcscb.c and arch/arm/mach-vexpress/tc2_pm.c.
>
> I suggest you add a compatibility macro in include/linux/arm-cci.h that
> may look like:
>
> #define cci_disable_port_by_cpu(mpidr) cci_control_port_by_cpu(mpidr, false)
>
> ... or at least update existing callers.

Thanks for the review.
This was an oversight on my part as our internal 3.8 based tree did
not have any users of this.
I will update the patch so that it does not break any existing callers.


Regards,
Abhilash
>
>
>> ---
>>  drivers/bus/arm-cci.c   |   13 +++++++------
>>  include/linux/arm-cci.h |    7 +++++--
>>  2 files changed, 12 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/bus/arm-cci.c b/drivers/bus/arm-cci.c
>> index 5a86da9..5668b40 100644
>> --- a/drivers/bus/arm-cci.c
>> +++ b/drivers/bus/arm-cci.c
>> @@ -763,10 +763,11 @@ static void notrace cci_port_control(unsigned int port, bool enable)
>>  }
>>
>>  /**
>> - * cci_disable_port_by_cpu() - function to disable a CCI port by CPU
>> + * cci_control_port_by_cpu() - function to control a CCI port by CPU
>>   *                          reference
>>   *
>> - * @mpidr: mpidr of the CPU whose CCI port should be disabled
>> + * @mpidr: mpidr of the CPU whose CCI port should be enabled/disabled
>> + * @enable: if true enables the port, if false disables it
>>   *
>>   * Disabling a CCI port for a CPU implies disabling the CCI port
>>   * controlling that CPU cluster. Code disabling CPU CCI ports
>> @@ -777,20 +778,20 @@ static void notrace cci_port_control(unsigned int port, bool enable)
>>   *   0 on success
>>   *   -ENODEV on port look-up failure
>>   */
>> -int notrace cci_disable_port_by_cpu(u64 mpidr)
>> +int notrace cci_control_port_by_cpu(u64 mpidr, bool enable)
>>  {
>>       int cpu;
>>       bool is_valid;
>>       for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
>>               is_valid = cpu_port_is_valid(&cpu_port[cpu]);
>>               if (is_valid && cpu_port_match(&cpu_port[cpu], mpidr)) {
>> -                     cci_port_control(cpu_port[cpu].port, false);
>> +                     cci_port_control(cpu_port[cpu].port, enable);
>>                       return 0;
>>               }
>>       }
>>       return -ENODEV;
>>  }
>> -EXPORT_SYMBOL_GPL(cci_disable_port_by_cpu);
>> +EXPORT_SYMBOL_GPL(cci_control_port_by_cpu);
>>
>>  /**
>>   * cci_enable_port_for_self() - enable a CCI port for calling CPU
>> @@ -936,7 +937,7 @@ int notrace __cci_control_port_by_index(u32 port, bool enable)
>>       /*
>>        * CCI control for ports connected to CPUS is extremely fragile
>>        * and must be made to go through a specific and controlled
>> -      * interface (ie cci_disable_port_by_cpu(); control by general purpose
>> +      * interface (ie cci_control_port_by_cpu(); control by general purpose
>>        * indexing is therefore disabled for ACE ports.
>>        */
>>       if (ports[port].type == ACE_PORT)
>> diff --git a/include/linux/arm-cci.h b/include/linux/arm-cci.h
>> index 79d6edf..c6c3ed0 100644
>> --- a/include/linux/arm-cci.h
>> +++ b/include/linux/arm-cci.h
>> @@ -29,7 +29,7 @@ struct device_node;
>>  #ifdef CONFIG_ARM_CCI
>>  extern bool cci_probed(void);
>>  extern int cci_ace_get_port(struct device_node *dn);
>> -extern int cci_disable_port_by_cpu(u64 mpidr);
>> +extern int cci_control_port_by_cpu(u64 mpidr, bool enable);
>>  extern int __cci_control_port_by_device(struct device_node *dn, bool enable);
>>  extern int __cci_control_port_by_index(u32 port, bool enable);
>>  #else
>> @@ -38,7 +38,10 @@ static inline int cci_ace_get_port(struct device_node *dn)
>>  {
>>       return -ENODEV;
>>  }
>> -static inline int cci_disable_port_by_cpu(u64 mpidr) { return -ENODEV; }
>> +static inline int cci_disable_port_by_cpu(u64 mpidr, bool enable)
>> +{
>> +     return -ENODEV;
>> +}
>>  static inline int __cci_control_port_by_device(struct device_node *dn,
>>                                              bool enable)
>>  {
>> --
>> 1.7.9.5
>>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel