Commit beea8df8 authored by Zhang Rui's avatar Zhang Rui Committed by Rafael J. Wysocki
Browse files

intel_rapl: abstract register access operations 



MSR and MMIO RAPL interfaces have different ways to access the registers,
thus in order to abstract the register access operations, two callbacks,
.read_raw()/.write_raw() are introduced, and they should be implemented by
MSR RAPL and MMIO RAPL interface driver respectly.

This patch implements them for the MSR I/F only.

Reviewed-by: default avatarPandruvada, Srinivas <srinivas.pandruvada@intel.com>
Tested-by: default avatarPandruvada, Srinivas <srinivas.pandruvada@intel.com>
Signed-off-by: default avatarZhang Rui <rui.zhang@intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 7fde2712

drivers/powercap/intel_rapl.c

+57 −53
Original line number Diff line number Diff line
@@ -93,13 +93,6 @@ static struct rapl_if_priv rapl_msr_priv = { 
/* per domain data, some are optional */

#define NR_RAW_PRIMITIVES (NR_RAPL_PRIMITIVES - 2)



struct msrl_action {

	u32 msr_no;

	u64 clear_mask;

	u64 set_mask;

	int err;

};



#define	DOMAIN_STATE_INACTIVE           BIT(0)

#define	DOMAIN_STATE_POWER_LIMIT_SET    BIT(1)

#define DOMAIN_STATE_BIOS_LOCKED        BIT(2)
@@ -692,16 +685,16 @@ static int rapl_read_data_raw(struct rapl_domain *rd, 
			enum rapl_primitives prim,

			bool xlate, u64 *data)

{

	u64 value, final;

	u32 msr;

	u64 value;

	struct rapl_primitive_info *rp = &rpi[prim];

	struct reg_action ra;

	int cpu;



	if (!rp->name || rp->flag & RAPL_PRIMITIVE_DUMMY)

		return -EINVAL;



	msr = rd->regs[rp->id];

	if (!msr)

	ra.reg = rd->regs[rp->id];

	if (!ra.reg)

		return -EINVAL;



	cpu = rd->rp->lead_cpu;
@@ -717,47 +710,23 @@ static int rapl_read_data_raw(struct rapl_domain *rd, 
		return 0;

	}



	if (rdmsrl_safe_on_cpu(cpu, msr, &value)) {

		pr_debug("failed to read msr 0x%x on cpu %d\n", msr, cpu);

	ra.mask = rp->mask;



	if (rd->rp->priv->read_raw(cpu, &ra)) {

		pr_debug("failed to read reg 0x%x on cpu %d\n", ra.reg, cpu);

		return -EIO;

	}



	final = value & rp->mask;

	final = final >> rp->shift;

	value = ra.value >> rp->shift;



	if (xlate)

		*data = rapl_unit_xlate(rd, rp->unit, final, 0);

		*data = rapl_unit_xlate(rd, rp->unit, value, 0);

	else

		*data = final;

		*data = value;



	return 0;

}





static int msrl_update_safe(u32 msr_no, u64 clear_mask, u64 set_mask)

{

	int err;

	u64 val;



	err = rdmsrl_safe(msr_no, &val);

	if (err)

		goto out;



	val &= ~clear_mask;

	val |= set_mask;



	err = wrmsrl_safe(msr_no, val);



out:

	return err;

}



static void msrl_update_func(void *info)

{

	struct msrl_action *ma = info;



	ma->err = msrl_update_safe(ma->msr_no, ma->clear_mask, ma->set_mask);

}



/* Similar use of primitive info in the read counterpart */

static int rapl_write_data_raw(struct rapl_domain *rd,

			enum rapl_primitives prim,
@@ -766,7 +735,7 @@ static int rapl_write_data_raw(struct rapl_domain *rd, 
	struct rapl_primitive_info *rp = &rpi[prim];

	int cpu;

	u64 bits;

	struct msrl_action ma;

	struct reg_action ra;

	int ret;



	cpu = rd->rp->lead_cpu;
@@ -774,17 +743,13 @@ static int rapl_write_data_raw(struct rapl_domain *rd, 
	bits <<= rp->shift;

	bits &= rp->mask;



	memset(&ma, 0, sizeof(ma));

	memset(&ra, 0, sizeof(ra));



	ma.msr_no = rd->regs[rp->id];

	ma.clear_mask = rp->mask;

	ma.set_mask = bits;

	ra.reg = rd->regs[rp->id];

	ra.mask = rp->mask;

	ra.value = bits;



	ret = smp_call_function_single(cpu, msrl_update_func, &ma, 1);

	if (ret)

		WARN_ON_ONCE(ret);

	else

		ret = ma.err;

	ret = rd->rp->priv->write_raw(cpu, &ra);



	return ret;

}
@@ -1507,6 +1472,43 @@ static struct notifier_block rapl_pm_notifier = { 
	.notifier_call = rapl_pm_callback,

};



static int rapl_msr_read_raw(int cpu, struct reg_action *ra)

{

	if (rdmsrl_safe_on_cpu(cpu, ra->reg, &ra->value)) {

		pr_debug("failed to read msr 0x%x on cpu %d\n", ra->reg, cpu);

		return -EIO;

	}

	ra->value &= ra->mask;

	return 0;

}



static void rapl_msr_update_func(void *info)

{

	struct reg_action *ra = info;

	u64 val;



	ra->err = rdmsrl_safe(ra->reg, &val);

	if (ra->err)

		return;



	val &= ~ra->mask;

	val |= ra->value;



	ra->err = wrmsrl_safe(ra->reg, val);

}





static int rapl_msr_write_raw(int cpu, struct reg_action *ra)

{

	int ret;



	ret = smp_call_function_single(cpu, rapl_msr_update_func, ra, 1);

	if (WARN_ON_ONCE(ret))

		return ret;



	return ra->err;

}



static int __init rapl_init(void)

{

	const struct x86_cpu_id *id;
@@ -1522,6 +1524,8 @@ static int __init rapl_init(void) 


	rapl_defaults = (struct rapl_defaults *)id->driver_data;



	rapl_msr_priv.read_raw = rapl_msr_read_raw;

	rapl_msr_priv.write_raw = rapl_msr_write_raw;

	ret = rapl_register_powercap();

	if (ret)

		return ret;

include/linux/intel_rapl.h

+13 −0
Original line number Diff line number Diff line
@@ -88,6 +88,13 @@ struct rapl_domain { 
	struct rapl_package *rp;

};



struct reg_action {

	u32 reg;

	u64 mask;

	u64 value;

	int err;

};



/**

 * struct rapl_if_priv: private data for different RAPL interfaces

 * @control_type:		Each RAPL interface must have its own powercap
@@ -97,6 +104,10 @@ struct rapl_domain { 
 * @pcap_rapl_online:		CPU hotplug state for each RAPL interface.

 * @reg_unit:			Register for getting energy/power/time unit.

 * @regs:			Register sets for different RAPL Domains.

 * @read_raw:			Callback for reading RAPL interface specific

 *				registers.

 * @write_raw:			Callback for writing RAPL interface specific

 *				registers.

 */

struct rapl_if_priv {

	struct powercap_control_type *control_type;
@@ -104,6 +115,8 @@ struct rapl_if_priv { 
	enum cpuhp_state pcap_rapl_online;

	u32 reg_unit;

	u32 regs[RAPL_DOMAIN_MAX][RAPL_DOMAIN_REG_MAX];

	int (*read_raw)(int cpu, struct reg_action *ra);

	int (*write_raw)(int cpu, struct reg_action *ra);

};



/* maximum rapl package domain name: package-%d-die-%d */

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