Re: [PATCH v3] hwmon: xgene: Support hwmon v2

[Hoan Tran]

Hi Guenter,

On Fri, Oct 13, 2017 at 9:28 PM, Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> On 10/13/2017 04:10 PM, Hoan Tran wrote:
>>
>> This patch supports xgene-hwmon v2 which uses the non-cachable memory
>> as the PCC shared memory.
>>
>> Signed-off-by: Hoan Tran <hotran@xxxxxxx>
>> ---
>> v3
>>   - Use local version variable
>>   - Use inline calls instead of the private map function
>>
>> v2
>>   - Map PCC shared mem by ioremap() in case hwmon is v2
>>
>>   drivers/hwmon/xgene-hwmon.c | 40
>> +++++++++++++++++++++++++++++++---------
>>   1 file changed, 31 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/hwmon/xgene-hwmon.c b/drivers/hwmon/xgene-hwmon.c
>> index 9c0dbb8..6b6c732 100644
>> --- a/drivers/hwmon/xgene-hwmon.c
>> +++ b/drivers/hwmon/xgene-hwmon.c
>> @@ -91,6 +91,11 @@
>>   #define to_xgene_hwmon_dev(cl)                \
>>         container_of(cl, struct xgene_hwmon_dev, mbox_client)
>>   +enum xgene_hwmon_version {
>> +       XGENE_HWMON_V1 = 0,
>> +       XGENE_HWMON_V2 = 1,
>> +};
>> +
>>   struct slimpro_resp_msg {
>>         u32 msg;
>>         u32 param1;
>> @@ -609,6 +614,15 @@ static void xgene_hwmon_tx_done(struct mbox_client
>> *cl, void *msg, int ret)
>>         }
>>   }
>>   +#ifdef CONFIG_ACPI
>> +static const struct acpi_device_id xgene_hwmon_acpi_match[] = {
>> +       {"APMC0D29", XGENE_HWMON_V1},
>> +       {"APMC0D8A", XGENE_HWMON_V2},
>> +       {},
>> +};
>> +MODULE_DEVICE_TABLE(acpi, xgene_hwmon_acpi_match);
>> +#endif
>> +
>>   static int xgene_hwmon_probe(struct platform_device *pdev)
>>   {
>>         struct xgene_hwmon_dev *ctx;
>> @@ -650,6 +664,16 @@ static int xgene_hwmon_probe(struct platform_device
>> *pdev)
>>                 }
>>         } else {
>>                 struct acpi_pcct_hw_reduced *cppc_ss;
>> +               const struct acpi_device_id *acpi_id;
>> +               int version;
>> +
>> +#ifdef CONFIG_ACPI
>> +               acpi_id = acpi_match_device(xgene_hwmon_acpi_match,
>> &pdev->dev);
>> +               if (!acpi_id)
>> +                       return -EINVAL;
>> +
>> +               version = (int)acpi_id->driver_data;
>> +#endif
>>
>
> This leaves "version" uninitialized if CONFIG_ACPI is not defined.

If CONFIG_ACPI is not defined, "acpi_disabled" is true. So this piece
of code is not executed

Thanks
Hoan

>
> Guenter
>
>
>>                 if (device_property_read_u32(&pdev->dev, "pcc-channel",
>>                                              &ctx->mbox_idx)) {
>> @@ -690,7 +714,13 @@ static int xgene_hwmon_probe(struct platform_device
>> *pdev)
>>                  */
>>                 ctx->comm_base_addr = cppc_ss->base_address;
>>                 if (ctx->comm_base_addr) {
>> -                       ctx->pcc_comm_addr = memremap(ctx->comm_base_addr,
>> +                       if (version == XGENE_HWMON_V2)
>> +                               ctx->pcc_comm_addr = (void __force
>> *)ioremap(
>> +
>> ctx->comm_base_addr,
>> +                                                       cppc_ss->length);
>> +                       else
>> +                               ctx->pcc_comm_addr = memremap(
>> +
>> ctx->comm_base_addr,
>>                                                         cppc_ss->length,
>>                                                         MEMREMAP_WB);
>>                 } else {
>> @@ -758,14 +788,6 @@ static int xgene_hwmon_remove(struct platform_device
>> *pdev)
>>         return 0;
>>   }
>>   -#ifdef CONFIG_ACPI
>> -static const struct acpi_device_id xgene_hwmon_acpi_match[] = {
>> -       {"APMC0D29", 0},
>> -       {},
>> -};
>> -MODULE_DEVICE_TABLE(acpi, xgene_hwmon_acpi_match);
>> -#endif
>> -
>>   static const struct of_device_id xgene_hwmon_of_match[] = {
>>         {.compatible = "apm,xgene-slimpro-hwmon"},
>>         {}
>>
>