Commit d0ba7ad4 authored by Shyam Sundar S K's avatar Shyam Sundar S K Committed by Hans de Goede
Browse files

platform/x86/amd/pmf: Add support to update system state 



PMF driver based on the output actions from the TA can request to update
the system states like entering s0i3, lock screen etc. by generating
an uevent. Based on the udev rules set in the userspace the event id
matching the uevent shall get updated accordingly using the systemctl.

Sample udev rules under Documentation/admin-guide/pmf.rst.

Reviewed-by: default avatarMario Limonciello <mario.limonciello@amd.com>
Signed-off-by: default avatarShyam Sundar S K <Shyam-sundar.S-k@amd.com>
Link: https://lore.kernel.org/r/20231212014705.2017474-9-Shyam-sundar.S-k@amd.com


Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
parent c3b40930

Documentation/admin-guide/index.rst

+1 −0
Original line number Diff line number Diff line
@@ -119,6 +119,7 @@ configure specific aspects of kernel behavior to your liking. 
   parport

   perf-security

   pm/index

   pmf

   pnp

   rapidio

   ras

Documentation/admin-guide/pmf.rst

0 → 100644
+24 −0
Original line number Diff line number Diff line 
.. SPDX-License-Identifier: GPL-2.0



Set udev rules for PMF Smart PC Builder

---------------------------------------



AMD PMF(Platform Management Framework) Smart PC Solution builder has to set the system states

like S0i3, Screen lock, hibernate etc, based on the output actions provided by the PMF

TA (Trusted Application).



In order for this to work the PMF driver generates a uevent for userspace to react to. Below are

sample udev rules that can facilitate this experience when a machine has PMF Smart PC solution builder

enabled.



Please add the following line(s) to

``/etc/udev/rules.d/99-local.rules``::



        DRIVERS=="amd-pmf", ACTION=="change", ENV{EVENT_ID}=="0", RUN+="/usr/bin/systemctl suspend"

        DRIVERS=="amd-pmf", ACTION=="change", ENV{EVENT_ID}=="1", RUN+="/usr/bin/systemctl hibernate"

        DRIVERS=="amd-pmf", ACTION=="change", ENV{EVENT_ID}=="2", RUN+="/bin/loginctl lock-sessions"



EVENT_ID values:

0= Put the system to S0i3/S2Idle

1= Put the system to hibernate

2= Lock the screen

drivers/platform/x86/amd/pmf/pmf.h

+9 −0
Original line number Diff line number Diff line
@@ -73,6 +73,7 @@ 
#define PMF_POLICY_STT_MIN					6

#define PMF_POLICY_STT_SKINTEMP_APU				7

#define PMF_POLICY_STT_SKINTEMP_HS2				8

#define PMF_POLICY_SYSTEM_STATE					9

#define PMF_POLICY_P3T						38



/* TA macros */
@@ -445,6 +446,13 @@ enum smart_pc_status { 
};



/* Smart PC - TA internals */

enum system_state {

	SYSTEM_STATE_S0i3,

	SYSTEM_STATE_S4,

	SYSTEM_STATE_SCREEN_LOCK,

	SYSTEM_STATE_MAX,

};



enum ta_slider {

	TA_BEST_BATTERY,

	TA_BETTER_BATTERY,
@@ -476,6 +484,7 @@ enum ta_pmf_error_type { 
};



struct pmf_action_table {

	enum system_state system_state;

	u32 spl;		/* in mW */

	u32 sppt;		/* in mW */

	u32 sppt_apuonly;	/* in mW */

drivers/platform/x86/amd/pmf/tee-if.c

+34 −0
Original line number Diff line number Diff line
@@ -24,6 +24,20 @@ MODULE_PARM_DESC(pb_actions_ms, "Policy binary actions sampling frequency (defau 
static const uuid_t amd_pmf_ta_uuid = UUID_INIT(0x6fd93b77, 0x3fb8, 0x524d,

						0xb1, 0x2d, 0xc5, 0x29, 0xb1, 0x3d, 0x85, 0x43);



static const char *amd_pmf_uevent_as_str(unsigned int state)

{

	switch (state) {

	case SYSTEM_STATE_S0i3:

		return "S0i3";

	case SYSTEM_STATE_S4:

		return "S4";

	case SYSTEM_STATE_SCREEN_LOCK:

		return "SCREEN_LOCK";

	default:

		return "Unknown Smart PC event";

	}

}



static void amd_pmf_prepare_args(struct amd_pmf_dev *dev, int cmd,

				 struct tee_ioctl_invoke_arg *arg,

				 struct tee_param *param)
@@ -42,6 +56,20 @@ static void amd_pmf_prepare_args(struct amd_pmf_dev *dev, int cmd, 
	param[0].u.memref.shm_offs = 0;

}



static int amd_pmf_update_uevents(struct amd_pmf_dev *dev, u16 event)

{

	char *envp[2] = {};



	envp[0] = kasprintf(GFP_KERNEL, "EVENT_ID=%d", event);

	if (!envp[0])

		return -EINVAL;



	kobject_uevent_env(&dev->dev->kobj, KOBJ_CHANGE, envp);



	kfree(envp[0]);

	return 0;

}



static void amd_pmf_apply_policies(struct amd_pmf_dev *dev, struct ta_pmf_enact_result *out)

{

	u32 val;
@@ -113,6 +141,12 @@ static void amd_pmf_apply_policies(struct amd_pmf_dev *dev, struct ta_pmf_enact_ 
				dev->prev_data->p3t_limit = val;

			}

			break;



		case PMF_POLICY_SYSTEM_STATE:

			amd_pmf_update_uevents(dev, val);

			dev_dbg(dev->dev, "update SYSTEM_STATE: %s\n",

				amd_pmf_uevent_as_str(val));

			break;

		}

	}

}