Re: [PATCH v3] platform/x86: Add support for improved performance mode

[Mario Limonciello <mario.limonciello@amd.com>]

On 11/13/2023 11:15, Mark Pearson wrote:
> Thanks Ilpo,
> 
> On Mon, Nov 13, 2023, at 11:59 AM, Ilpo Järvinen wrote:
>> On Mon, 13 Nov 2023, Mark Pearson wrote:
>>
>>> Some new Thinkpads have a new improved performance mode available.
>>> Add support to make this mode usable.
>>>
>>> To avoid having to create a new profile, just use the improved performance
>>> mode in place of the existing performance mode, when available.
>>>
>>> Tested on P14s AMD G4 AMD.
>>>
>>> Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
>>> ---
>>> Changes in v2: updated implementation for DYTC_UP_SUPPORT define
>>> Changes in v3:
>>>   - Add in missing BIT for define, somehow lost in previous commit
>>>   - Cosmetic clean-ups
>>>
>>>   drivers/platform/x86/thinkpad_acpi.c | 28 ++++++++++++++++++++++++++++
>>>   1 file changed, 28 insertions(+)
>>>
>>> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
>>> index ad460417f901..3a9d2cc71b6a 100644
>>> --- a/drivers/platform/x86/thinkpad_acpi.c
>>> +++ b/drivers/platform/x86/thinkpad_acpi.c
>>> @@ -10136,6 +10136,7 @@ static struct ibm_struct proxsensor_driver_data = {
>>>   
>>>   #define DYTC_CMD_SET          1 /* To enable/disable IC function mode */
>>>   #define DYTC_CMD_MMC_GET      8 /* To get current MMC function and mode */
>>> +#define DYTC_CMD_UP_CAP     0xA /* To get Ultra-performance capability */
>>>   #define DYTC_CMD_RESET    0x1ff /* To reset back to default */
>>>   
>>>   #define DYTC_CMD_FUNC_CAP     3 /* To get DYTC capabilities */
>>> @@ -10152,6 +10153,7 @@ static struct ibm_struct proxsensor_driver_data = {
>>>   
>>>   #define DYTC_FUNCTION_STD     0  /* Function = 0, standard mode */
>>>   #define DYTC_FUNCTION_CQL     1  /* Function = 1, lap mode */
>>> +#define DYTC_FUNCTION_TMS     9  /* Function = 9, TMS mode */
>>>   #define DYTC_FUNCTION_MMC     11 /* Function = 11, MMC mode */
>>>   #define DYTC_FUNCTION_PSC     13 /* Function = 13, PSC mode */
>>>   #define DYTC_FUNCTION_AMT     15 /* Function = 15, AMT mode */
>>> @@ -10163,11 +10165,14 @@ static struct ibm_struct proxsensor_driver_data = {
>>>   #define DYTC_MODE_MMC_LOWPOWER 3  /* Low power mode */
>>>   #define DYTC_MODE_MMC_BALANCE  0xF  /* Default mode aka balanced */
>>>   #define DYTC_MODE_MMC_DEFAULT  0  /* Default mode from MMC_GET, aka balanced */
>>> +#define DYTC_NOMODE            0xF  /* When Function does not have a mode */
>>>   
>>>   #define DYTC_MODE_PSC_LOWPOWER 3  /* Low power mode */
>>>   #define DYTC_MODE_PSC_BALANCE  5  /* Default mode aka balanced */
>>>   #define DYTC_MODE_PSC_PERFORM  7  /* High power mode aka performance */
>>>   
>>> +#define DYTC_UP_SUPPORT    BIT(8)  /* Ultra-performance (TMS) mode support */
>>> +
>>>   #define DYTC_ERR_MASK       0xF  /* Bits 0-3 in cmd result are the error result */
>>>   #define DYTC_ERR_SUCCESS      1  /* CMD completed successful */
>>>   
>>> @@ -10185,6 +10190,7 @@ static enum platform_profile_option dytc_current_profile;
>>>   static atomic_t dytc_ignore_event = ATOMIC_INIT(0);
>>>   static DEFINE_MUTEX(dytc_mutex);
>>>   static int dytc_capabilities;
>>> +static bool dytc_ultraperf_cap;
>>>   static bool dytc_mmc_get_available;
>>>   static int profile_force;
>>>   
>>> @@ -10355,6 +10361,17 @@ static int dytc_profile_set(struct platform_profile_handler *pprof,
>>>   	if (err)
>>>   		goto unlock;
>>>   
>>> +	/* Set TMS mode appropriately (enable for performance), if available */
>>> +	if (dytc_ultraperf_cap) {
>>> +		int cmd;
>>> +
>>> +		cmd = DYTC_SET_COMMAND(DYTC_FUNCTION_TMS, DYTC_NOMODE,
>>> +				       profile == PLATFORM_PROFILE_PERFORMANCE);
>>> +		err = dytc_command(cmd, &output);
>>> +		if (err)
>>> +			return err;
>>> +	}
>>> +
>>>   	if (dytc_capabilities & BIT(DYTC_FC_MMC)) {
>>>   		if (profile == PLATFORM_PROFILE_BALANCED) {
>>>   			/*
>>> @@ -10429,6 +10446,7 @@ static struct platform_profile_handler dytc_profile = {
>>>   static int tpacpi_dytc_profile_init(struct ibm_init_struct *iibm)
>>>   {
>>>   	int err, output;
>>> +	int cmd;
>>>   
>>>   	/* Setup supported modes */
>>>   	set_bit(PLATFORM_PROFILE_LOW_POWER, dytc_profile.choices);
>>> @@ -10484,6 +10502,16 @@ static int tpacpi_dytc_profile_init(struct ibm_init_struct *iibm)
>>>   		dbg_printk(TPACPI_DBG_INIT, "No DYTC support available\n");
>>>   		return -ENODEV;
>>>   	}
>>> +	err = dytc_command(DYTC_CMD_UP_CAP, &output);
>>
>> Hmm, are you missing error handling here?
>>
> Doh....yes, it should check that. My bad.
> 
> I'll hold off a day or two on the next patch so I'm not spamming the list in case there is other feedback, and do a fix for that.
> I don't want the driver to error out on this - but it shouldn't check (and potentially enable) the feature if that register read fails. I will go and double check on some older platforms too as a sanity check.
> 
> Thanks for the review.
> Mark

Probably best to "catch" the error and just spit it out to dynamic 
debugging then.  If problems come up on anything from calling this that 
could give people a nice path to turn up the debug logs and share them 
to you.