[PATCH v2 2/3] drm/amd/pm: send the SMT enable message to pmfw

[Lazar, Lijo]

On 3/27/2023 12:54 PM, Wenyou Yang wrote:
> When the CPU SMT status is changed in the fly, sent the SMT enable
> message to pmfw to notify it that the SMT status changed.
> 
> Signed-off-by: Wenyou Yang <WenYou.Yang at amd.com>
> ---
>   drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c     | 39 +++++++++++++++++++
>   drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h |  7 ++++
>   2 files changed, 46 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> index b5d64749990e..eb4c49f38292 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> @@ -22,6 +22,7 @@
>   
>   #define SWSMU_CODE_LAYER_L1
>   
> +#include <linux/cpu.h>
>   #include <linux/firmware.h>
>   #include <linux/pci.h>
>   
> @@ -54,6 +55,8 @@
>   #undef pr_info
>   #undef pr_debug
>   
> +extern struct raw_notifier_head smt_notifier_head;
> +
>   static const struct amd_pm_funcs swsmu_pm_funcs;
>   static int smu_force_smuclk_levels(struct smu_context *smu,
>   				   enum smu_clk_type clk_type,
> @@ -69,6 +72,9 @@ static int smu_set_fan_speed_rpm(void *handle, uint32_t speed);
>   static int smu_set_gfx_cgpg(struct smu_context *smu, bool enabled);
>   static int smu_set_mp1_state(void *handle, enum pp_mp1_state mp1_state);
>   
> +static int smt_notifier_callback(struct notifier_block *nb,
> +				 unsigned long action, void *data);
> +
>   static int smu_sys_get_pp_feature_mask(void *handle,
>   				       char *buf)
>   {
> @@ -647,6 +653,8 @@ static int smu_early_init(void *handle)
>   	adev->powerplay.pp_handle = smu;
>   	adev->powerplay.pp_funcs = &swsmu_pm_funcs;
>   
> +	smu->nb.notifier_call = smt_notifier_callback;
> +
>   	r = smu_set_funcs(adev);
>   	if (r)
>   		return r;
> @@ -1105,6 +1113,8 @@ static int smu_sw_init(void *handle)
>   	if (!smu->ppt_funcs->get_fan_control_mode)
>   		smu->adev->pm.no_fan = true;
>   
> +	raw_notifier_chain_register(&smt_notifier_head, &smu->nb);
> +

As mentioned before, it's not a blind registration for any ASIC. This 
should only be done by the ASICs which are interested in the 
notification and not here. So this should be somewhere inside 
vangogh_set_ppt_funcs or part of a software init callback like 
vangogh_init_smc_tables.

Thanks,
Lijo

>   	return 0;
>   }
>   
> @@ -1122,6 +1132,9 @@ static int smu_sw_fini(void *handle)
>   
>   	smu_fini_microcode(smu);
>   
> +	if (smu->nb.notifier_call != NULL)
> +		raw_notifier_chain_unregister(&smt_notifier_head, &smu->nb);
> +
>   	return 0;
>   }
>   
> @@ -3241,3 +3254,29 @@ int smu_send_hbm_bad_channel_flag(struct smu_context *smu, uint32_t size)
>   
>   	return ret;
>   }
> +
> +static int smu_set_cpu_smt_enable(struct smu_context *smu, bool enable)
> +{
> +	int ret = -EINVAL;
> +
> +	if (smu->ppt_funcs && smu->ppt_funcs->set_cpu_smt_enable)
> +		ret = smu->ppt_funcs->set_cpu_smt_enable(smu, enable);
> +
> +	return ret;
> +}
> +
> +static int smt_notifier_callback(struct notifier_block *nb,
> +				 unsigned long action, void *data)
> +{
> +	struct smu_context *smu = container_of(nb, struct smu_context, nb);
> +	int ret;
> +
> +	smu = container_of(nb, struct smu_context, nb);
> +
> +	ret = smu_set_cpu_smt_enable(smu, action == SMT_ENABLED);
> +
> +	dev_dbg(smu->adev->dev, "failed to set cclk_pd_limit for SMT %sabled: %d\n",
> +		action == SMT_ENABLED ?	"en" : "dis", ret);
> +
> +	return ret ? NOTIFY_BAD : NOTIFY_OK;
> +}
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h b/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> index 09469c750a96..4d51ac5ec8ba 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> +++ b/drivers/gpu/drm/amd/pm/swsmu/inc/amdgpu_smu.h
> @@ -566,6 +566,8 @@ struct smu_context
>   
>   	struct firmware pptable_firmware;
>   
> +	struct notifier_block nb;
> +
>   	u32 param_reg;
>   	u32 msg_reg;
>   	u32 resp_reg;
> @@ -1354,6 +1356,11 @@ struct pptable_funcs {
>   	 * @init_pptable_microcode: Prepare the pptable microcode to upload via PSP
>   	 */
>   	int (*init_pptable_microcode)(struct smu_context *smu);
> +
> +	/**
> +	 * @set_cpu_smt_enable: Set the CPU SMT status.
> +	 */
> +	int (*set_cpu_smt_enable)(struct smu_context *smu, bool smt_enable);
>   };
>   
>   typedef enum {