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

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Wed, 8 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 T14 AMD G4 AMD.
> 
> Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
> ---
>  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..eba701ab340e 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  /* Bit 8 - 1 = supported, 0 = not */

It would be preferrable to comment what is supported rather than have a 
comment like above which isn't particularly helpful.

>  #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; /* ultra performance capable */
>  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);
> +	dytc_ultraperf_cap = output & BIT(DYTC_UP_SUPPORT_BIT) ? true : false;

It would be better to put this BIT() into the define itself and remove 
_BIT from the name because it doesn't really add that much information.
Since you're assigning to bool, ? true : false construct is not required 
but implicit cast will handle it for you. So in the end, this line would 
be:

	dytc_ultraperf_cap = output & DYTC_UP_SUPPORT;

Looking into the driver a bit more, there are a few other defines which 
could also move BIT() from the code into defines. Please tell if you're 
going to look at those because if not, I might try to make the patches.

> +	if (dytc_ultraperf_cap) {
> +		pr_debug("TMS is supported\n");
> +		/* Disable TMS by default - only use with performance mode */
> +		cmd = DYTC_SET_COMMAND(DYTC_FUNCTION_TMS, DYTC_NOMODE, 0);
> +		err = dytc_command(cmd, &output);
> +		if (err)
> +			return err;
> +	}
>  
>  	dbg_printk(TPACPI_DBG_INIT,
>  			"DYTC version %d: thermal mode available\n", dytc_version);
> 

-- 
 i.