[PATCH 7/8] ACPI: xen processor: add PM notification interfaces.

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

From: Kevin Tian <kevin.tian@intel.com>

Since cpu power is controlled by VMM in Xen, to provide
that information to the VMM, we have to use hypercall to exchange
power management state between domain with hypervisor.

Signed-off-by: Yu Ke <ke.yu@intel.com>
Signed-off-by: Tian Kevin <kevin.tian@intel.com>
Signed-off-by: Tang Liang <liang.tang@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 drivers/xen/acpi_processor.c |  216 ++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 216 insertions(+), 0 deletions(-)

diff --git a/drivers/xen/acpi_processor.c b/drivers/xen/acpi_processor.c
index 8fa7914..23730d8 100644
--- a/drivers/xen/acpi_processor.c
+++ b/drivers/xen/acpi_processor.c
@@ -24,6 +24,7 @@
 #include <acpi/processor.h>
 #include <xen/acpi.h>
 
+#include <xen/interface/platform.h>
 #include <asm/xen/hypercall.h>
 #include <asm/xen/hypervisor.h>
 
@@ -50,4 +51,219 @@ int processor_cntl_xen_notify(struct acpi_processor *pr, int event, int type)
 }
 EXPORT_SYMBOL(processor_cntl_xen_notify);
 
+static inline void xen_convert_pct_reg(struct xen_pct_register *xpct,
+	struct acpi_pct_register *apct)
+{
+	xpct->descriptor = apct->descriptor;
+	xpct->length     = apct->length;
+	xpct->space_id   = apct->space_id;
+	xpct->bit_width  = apct->bit_width;
+	xpct->bit_offset = apct->bit_offset;
+	xpct->reserved   = apct->reserved;
+	xpct->address    = apct->address;
+}
+
+static inline void xen_convert_pss_states(struct xen_processor_px *xpss,
+	struct acpi_processor_px *apss, int state_count)
+{
+	int i;
+	for (i = 0; i < state_count; i++) {
+		xpss->core_frequency     = apss->core_frequency;
+		xpss->power              = apss->power;
+		xpss->transition_latency = apss->transition_latency;
+		xpss->bus_master_latency = apss->bus_master_latency;
+		xpss->control            = apss->control;
+		xpss->status             = apss->status;
+		xpss++;
+		apss++;
+	}
+}
+
+static inline void xen_convert_psd_pack(struct xen_psd_package *xpsd,
+	struct acpi_psd_package *apsd)
+{
+	xpsd->num_entries    = apsd->num_entries;
+	xpsd->revision       = apsd->revision;
+	xpsd->domain         = apsd->domain;
+	xpsd->coord_type     = apsd->coord_type;
+	xpsd->num_processors = apsd->num_processors;
+}
+
+static int xen_cx_notifier(struct acpi_processor *pr, int action)
+{
+	int ret, count = 0, i;
+	struct xen_platform_op op = {
+		.cmd			= XENPF_set_processor_pminfo,
+		.interface_version	= XENPF_INTERFACE_VERSION,
+		.u.set_pminfo.id	= pr->acpi_id,
+		.u.set_pminfo.type	= XEN_PM_CX,
+	};
+	struct xen_processor_cx *data, *buf;
+	struct acpi_processor_cx *cx;
+	struct acpi_power_register *reg;
+
+	if (action == PROCESSOR_PM_CHANGE)
+		return -EINVAL;
+
+	/* Convert to Xen defined structure and hypercall */
+	buf = kzalloc(pr->power.count * sizeof(struct xen_processor_cx)\
+		, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	data = buf;
+	for (i = 1; i <= pr->power.count; i++) {
+		cx = &pr->power.states[i];
+		reg = &cx->reg;
+		/* Skip invalid cstate entry */
+		if (!cx->valid)
+			continue;
+
+		data->type = cx->type;
+		data->latency = cx->latency;
+		data->power = cx->power;
+		data->reg.space_id = reg->space_id;
+		data->reg.bit_width = reg->bit_width;
+		data->reg.bit_offset = reg->bit_offset;
+		data->reg.access_size = reg->access_size;
+		data->reg.address = reg->address;
+
+		/* Get dependency relationships, _CSD is not supported yet */
+		data->dpcnt = 0;
+		set_xen_guest_handle(data->dp, NULL);
+
+		data++;
+		count++;
+	}
+
+	if (!count) {
+		printk(KERN_ERR "No available Cx info for cpu %d\n",
+				pr->acpi_id);
+		kfree(buf);
+		return -EINVAL;
+	}
+
+	op.u.set_pminfo.power.count = count;
+	op.u.set_pminfo.power.flags.bm_control = pr->flags.bm_control;
+	op.u.set_pminfo.power.flags.bm_check = pr->flags.bm_check;
+	op.u.set_pminfo.power.flags.has_cst = pr->flags.has_cst;
+	op.u.set_pminfo.power.flags.power_setup_done =
+		pr->flags.power_setup_done;
+
+	set_xen_guest_handle(op.u.set_pminfo.power.states, buf);
+	ret = HYPERVISOR_dom0_op(&op);
+	kfree(buf);
+	return ret;
+}
+
+static int xen_px_notifier(struct acpi_processor *pr, int action)
+{
+	int ret = -EINVAL;
+	struct xen_platform_op op = {
+		.cmd			= XENPF_set_processor_pminfo,
+		.interface_version	= XENPF_INTERFACE_VERSION,
+		.u.set_pminfo.id	= pr->acpi_id,
+		.u.set_pminfo.type	= XEN_PM_PX,
+	};
+	struct xen_processor_performance *perf;
+	struct xen_processor_px *states = NULL;
+	struct acpi_processor_performance *px;
+	struct acpi_psd_package *pdomain;
+
+	if (!pr)
+		return -EINVAL;
+
+	perf = &op.u.set_pminfo.perf;
+	px = pr->performance;
+
+	switch (action) {
+	case PROCESSOR_PM_CHANGE:
+		/* ppc dynamic handle */
+		perf->flags = XEN_PX_PPC;
+		perf->platform_limit = pr->performance_platform_limit;
+
+		ret = HYPERVISOR_dom0_op(&op);
+		break;
+
+	case PROCESSOR_PM_INIT:
+		/* px normal init */
+		perf->flags = XEN_PX_PPC |
+			      XEN_PX_PCT |
+			      XEN_PX_PSS |
+			      XEN_PX_PSD;
+
+		/* ppc */
+		perf->platform_limit = pr->performance_platform_limit;
+
+		/* pct */
+		xen_convert_pct_reg(&perf->control_register,
+				&px->control_register);
+		xen_convert_pct_reg(&perf->status_register,
+				&px->status_register);
+
+		/* pss */
+		perf->state_count = px->state_count;
+		states = kzalloc(px->state_count*\
+			sizeof(struct xen_processor_px), GFP_KERNEL);
+		if (!states)
+			return -ENOMEM;
+		xen_convert_pss_states(states, px->states, px->state_count);
+		set_xen_guest_handle(perf->states, states);
+
+		/* psd */
+		pdomain = &px->domain_info;
+		/* Some sanity check */
+		if ((pdomain->revision != ACPI_PSD_REV0_REVISION) ||
+			(pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) ||
+			((pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL) &&
+			(pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY) &&
+			(pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL))) {
+			ret = -EINVAL;
+			kfree(states);
+			break;
+		}
+
+		xen_convert_psd_pack(&perf->domain_info, pdomain);
+		if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
+			perf->shared_type = CPUFREQ_SHARED_TYPE_ALL;
+		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
+			perf->shared_type = CPUFREQ_SHARED_TYPE_ANY;
+		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
+			perf->shared_type = CPUFREQ_SHARED_TYPE_HW;
+		else {
+			ret = -EINVAL;
+			kfree(states);
+			break;
+		}
+
+		ret = HYPERVISOR_dom0_op(&op);
+		kfree(states);
+		break;
+
+	default:
+		break;
+	}
+
+	return ret;
+}
+
+static int __init xen_acpi_processor_extcntl_init(void)
+{
+	unsigned int pmbits;
+
+	/* Only xen dom0 is allowed to handle ACPI processor info */
+	if (!xen_initial_domain())
+		return 0;
+
+	pmbits = (xen_start_info->flags & SIF_PM_MASK) >> 8;
+
+	if (pmbits & XEN_PROCESSOR_PM_CX)
+		xen_ops.pm_ops[PM_TYPE_IDLE] = xen_cx_notifier;
+	if (pmbits & XEN_PROCESSOR_PM_PX)
+		xen_ops.pm_ops[PM_TYPE_PERF] = xen_px_notifier;
+
+	return 0;
+}
+
+subsys_initcall(xen_acpi_processor_extcntl_init);
 MODULE_LICENSE("GPL");
-- 
1.7.7.3