Commit f35e5b3c authored by Lifeng Zheng's avatar Lifeng Zheng Committed by Rafael J. Wysocki
Browse files

ACPI: CPPC: Add three functions related to autonomous selection 



cppc_set_epp() - write energy performance preference register value,
based on ACPI 6.5, s8.4.6.1.7

cppc_get_auto_act_window() - read autonomous activity window register
value, based on ACPI 6.5, s8.4.6.1.6

cppc_set_auto_act_window() - write autonomous activity window register
value, based on ACPI 6.5, s8.4.6.1.6

Reviewed-by: default avatarPierre Gondois <pierre.gondois@arm.com>
Signed-off-by: default avatarLifeng Zheng <zhenglifeng1@huawei.com>
Reviewed-by: default avatarMario Limonciello <mario.limonciello@amd.com>
Link: https://patch.msgid.link/20250411093855.982491-9-zhenglifeng1@huawei.com


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 2605e4ab

drivers/acpi/cppc_acpi.c

+83 −0
Original line number Diff line number Diff line
@@ -1601,6 +1601,89 @@ int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable) 
}

EXPORT_SYMBOL_GPL(cppc_set_epp_perf);



/**

 * cppc_set_epp() - Write the EPP register.

 * @cpu: CPU on which to write register.

 * @epp_val: Value to write to the EPP register.

 */

int cppc_set_epp(int cpu, u64 epp_val)

{

	if (epp_val > CPPC_ENERGY_PERF_MAX)

		return -EINVAL;



	return cppc_set_reg_val(cpu, ENERGY_PERF, epp_val);

}

EXPORT_SYMBOL_GPL(cppc_set_epp);



/**

 * cppc_get_auto_act_window() - Read autonomous activity window register.

 * @cpu: CPU from which to read register.

 * @auto_act_window: Return address.

 *

 * According to ACPI 6.5, s8.4.6.1.6, the value read from the autonomous

 * activity window register consists of two parts: a 7 bits value indicate

 * significand and a 3 bits value indicate exponent.

 */

int cppc_get_auto_act_window(int cpu, u64 *auto_act_window)

{

	unsigned int exp;

	u64 val, sig;

	int ret;



	if (auto_act_window == NULL)

		return -EINVAL;



	ret = cppc_get_reg_val(cpu, AUTO_ACT_WINDOW, &val);

	if (ret)

		return ret;



	sig = val & CPPC_AUTO_ACT_WINDOW_MAX_SIG;

	exp = (val >> CPPC_AUTO_ACT_WINDOW_SIG_BIT_SIZE) & CPPC_AUTO_ACT_WINDOW_MAX_EXP;

	*auto_act_window = sig * int_pow(10, exp);



	return 0;

}

EXPORT_SYMBOL_GPL(cppc_get_auto_act_window);



/**

 * cppc_set_auto_act_window() - Write autonomous activity window register.

 * @cpu: CPU on which to write register.

 * @auto_act_window: usec value to write to the autonomous activity window register.

 *

 * According to ACPI 6.5, s8.4.6.1.6, the value to write to the autonomous

 * activity window register consists of two parts: a 7 bits value indicate

 * significand and a 3 bits value indicate exponent.

 */

int cppc_set_auto_act_window(int cpu, u64 auto_act_window)

{

	/* The max value to store is 1270000000 */

	u64 max_val = CPPC_AUTO_ACT_WINDOW_MAX_SIG * int_pow(10, CPPC_AUTO_ACT_WINDOW_MAX_EXP);

	int exp = 0;

	u64 val;



	if (auto_act_window > max_val)

		return -EINVAL;



	/*

	 * The max significand is 127, when auto_act_window is larger than

	 * 129, discard the precision of the last digit and increase the

	 * exponent by 1.

	 */

	while (auto_act_window > CPPC_AUTO_ACT_WINDOW_SIG_CARRY_THRESH) {

		auto_act_window /= 10;

		exp += 1;

	}



	/* For 128 and 129, cut it to 127. */

	if (auto_act_window > CPPC_AUTO_ACT_WINDOW_MAX_SIG)

		auto_act_window = CPPC_AUTO_ACT_WINDOW_MAX_SIG;



	val = (exp << CPPC_AUTO_ACT_WINDOW_SIG_BIT_SIZE) + auto_act_window;



	return cppc_set_reg_val(cpu, AUTO_ACT_WINDOW, val);

}

EXPORT_SYMBOL_GPL(cppc_set_auto_act_window);



/**

 * cppc_get_auto_sel() - Read autonomous selection register.

 * @cpu: CPU from which to read register.

include/acpi/cppc_acpi.h

+24 −0
Original line number Diff line number Diff line
@@ -32,6 +32,15 @@ 
#define	CMD_READ 0

#define	CMD_WRITE 1



#define CPPC_AUTO_ACT_WINDOW_SIG_BIT_SIZE	(7)

#define CPPC_AUTO_ACT_WINDOW_EXP_BIT_SIZE	(3)

#define CPPC_AUTO_ACT_WINDOW_MAX_SIG	((1 << CPPC_AUTO_ACT_WINDOW_SIG_BIT_SIZE) - 1)

#define CPPC_AUTO_ACT_WINDOW_MAX_EXP	((1 << CPPC_AUTO_ACT_WINDOW_EXP_BIT_SIZE) - 1)

/* CPPC_AUTO_ACT_WINDOW_MAX_SIG is 127, so 128 and 129 will decay to 127 when writing */

#define CPPC_AUTO_ACT_WINDOW_SIG_CARRY_THRESH 129



#define CPPC_ENERGY_PERF_MAX	(0xFF)



/* Each register has the folowing format. */

struct cpc_reg {

	u8 descriptor;
@@ -159,6 +168,9 @@ extern int cpc_read_ffh(int cpunum, struct cpc_reg *reg, u64 *val); 
extern int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val);

extern int cppc_get_epp_perf(int cpunum, u64 *epp_perf);

extern int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable);

extern int cppc_set_epp(int cpu, u64 epp_val);

extern int cppc_get_auto_act_window(int cpu, u64 *auto_act_window);

extern int cppc_set_auto_act_window(int cpu, u64 auto_act_window);

extern int cppc_get_auto_sel(int cpu, bool *enable);

extern int cppc_set_auto_sel(int cpu, bool enable);

extern int amd_get_highest_perf(unsigned int cpu, u32 *highest_perf);
@@ -229,6 +241,18 @@ static inline int cppc_get_epp_perf(int cpunum, u64 *epp_perf) 
{

	return -EOPNOTSUPP;

}

static inline int cppc_set_epp(int cpu, u64 epp_val)

{

	return -EOPNOTSUPP;

}

static inline int cppc_get_auto_act_window(int cpu, u64 *auto_act_window)

{

	return -EOPNOTSUPP;

}

static inline int cppc_set_auto_act_window(int cpu, u64 auto_act_window)

{

	return -EOPNOTSUPP;

}

static inline int cppc_get_auto_sel(int cpu, bool *enable)

{

	return -EOPNOTSUPP;