Adds a generic powercap framework to change the system powercap
inband through OPAL-OCC command/response interface.
Signed-off-by: Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com>
---
.../ABI/testing/sysfs-firmware-opal-powercap | 31 +++
arch/powerpc/include/asm/opal-api.h | 3 +
arch/powerpc/include/asm/opal.h | 5 +
arch/powerpc/platforms/powernv/Makefile | 2 +-
arch/powerpc/platforms/powernv/opal-powercap.c | 244 +++++++++++++++++++++
arch/powerpc/platforms/powernv/opal-wrappers.S | 2 +
arch/powerpc/platforms/powernv/opal.c | 4 +
7 files changed, 290 insertions(+), 1 deletion(-)
create mode 100644 Documentation/ABI/testing/sysfs-firmware-opal-powercap
create mode 100644 arch/powerpc/platforms/powernv/opal-powercap.c
diff --git a/Documentation/ABI/testing/sysfs-firmware-opal-powercap
b/Documentation/ABI/testing/sysfs-firmware-opal-powercap
new file mode 100644
index 0000000..c9b66ec
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-opal-powercap
@@ -0,0 +1,31 @@
+What: /sys/firmware/opal/powercap
+Date: August 2017
+Contact: Linux for PowerPC mailing list <linuxppc-...@ozlabs.org>
+Description: Powercap directory for Powernv (P8, P9) servers
+
+ Each folder in this directory contains a
+ power-cappable component.
+
+What: /sys/firmware/opal/powercap/system-powercap
+ /sys/firmware/opal/powercap/system-powercap/powercap-min
+ /sys/firmware/opal/powercap/system-powercap/powercap-max
+ /sys/firmware/opal/powercap/system-powercap/powercap-current
+Date: August 2017
+Contact: Linux for PowerPC mailing list <linuxppc-...@ozlabs.org>
+Description: System powercap directory and attributes applicable for
+ Powernv (P8, P9) servers
+
+ This directory provides powercap information. It
+ contains below sysfs attributes:
+
+ - powercap-min : This file provides the minimum
+ possible powercap in Watt units
+
+ - powercap-max : This file provides the maximum
+ possible powercap in Watt units
+
+ - powercap-current : This file provides the current
+ powercap set on the system. Writing to this file
+ creates a request for setting a new-powercap. The
+ powercap requested must be between powercap-min
+ and powercap-max.
diff --git a/arch/powerpc/include/asm/opal-api.h
b/arch/powerpc/include/asm/opal-api.h
index ced1ef2..b87305b 100644
--- a/arch/powerpc/include/asm/opal-api.h
+++ b/arch/powerpc/include/asm/opal-api.h
@@ -42,6 +42,7 @@
#define OPAL_I2C_STOP_ERR -24
#define OPAL_XIVE_PROVISIONING -31
#define OPAL_XIVE_FREE_ACTIVE -32
+#define OPAL_TIMEOUT -33
/* API Tokens (in r0) */
#define OPAL_INVALID_CALL -1
@@ -193,6 +194,8 @@
#define OPAL_IMC_COUNTERS_INIT 149
#define OPAL_IMC_COUNTERS_START 150
#define OPAL_IMC_COUNTERS_STOP 151
+#define OPAL_GET_POWERCAP 152
+#define OPAL_SET_POWERCAP 153
#define OPAL_PCI_SET_P2P 157
#define OPAL_LAST 157
diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
index 5a715e6..6f09ab7 100644
--- a/arch/powerpc/include/asm/opal.h
+++ b/arch/powerpc/include/asm/opal.h
@@ -275,6 +275,9 @@ int64_t opal_imc_counters_init(uint32_t type, uint64_t
address,
int64_t opal_imc_counters_start(uint32_t type, uint64_t cpu_pir);
int64_t opal_imc_counters_stop(uint32_t type, uint64_t cpu_pir);
+int opal_get_powercap(u32 handle, int token, u32 *pcap);
+int opal_set_powercap(u32 handle, int token, u32 pcap);
+
/* Internal functions */
extern int early_init_dt_scan_opal(unsigned long node, const char *uname,
int depth, void *data);
@@ -352,6 +355,8 @@ static inline int opal_get_async_rc(struct opal_msg msg)
void opal_wake_poller(void);
+void opal_powercap_init(void);
+
#endif /* __ASSEMBLY__ */
#endif /* _ASM_POWERPC_OPAL_H */
diff --git a/arch/powerpc/platforms/powernv/Makefile
b/arch/powerpc/platforms/powernv/Makefile
index a0d4353..f9ec36d 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -2,7 +2,7 @@ obj-y += setup.o opal-wrappers.o opal.o
opal-async.o idle.o
obj-y += opal-rtc.o opal-nvram.o opal-lpc.o opal-flash.o
obj-y += rng.o opal-elog.o opal-dump.o opal-sysparam.o
opal-sensor.o
obj-y += opal-msglog.o opal-hmi.o opal-power.o opal-irqchip.o
-obj-y += opal-kmsg.o
+obj-y += opal-kmsg.o opal-powercap.o
obj-$(CONFIG_SMP) += smp.o subcore.o subcore-asm.o
obj-$(CONFIG_PCI) += pci.o pci-ioda.o npu-dma.o
diff --git a/arch/powerpc/platforms/powernv/opal-powercap.c
b/arch/powerpc/platforms/powernv/opal-powercap.c
new file mode 100644
index 0000000..badb29b
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opal-powercap.c
@@ -0,0 +1,244 @@
+/*
+ * PowerNV OPAL Powercap interface
+ *
+ * Copyright 2017 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "opal-powercap: " fmt
+
+#include <linux/of.h>
+#include <linux/kobject.h>
+#include <linux/slab.h>
+
+#include <asm/opal.h>
+
+DEFINE_MUTEX(powercap_mutex);
+
+static struct kobject *powercap_kobj;
+
+struct powercap_attr {
+ u32 handle;
+ struct kobj_attribute attr;
+};
+
+static struct pcap {
+ struct attribute_group pg;
+ struct powercap_attr *pattrs;
+} *pcaps;
+
+static ssize_t powercap_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ struct powercap_attr *pcap_attr = container_of(attr,
+ struct powercap_attr, attr);
+ struct opal_msg msg;
+ u32 pcap;
+ int ret, token;
+
+ token = opal_async_get_token_interruptible();
+ if (token < 0) {
+ pr_devel("Failed to get token\n");
+ return token;
+ }
+
+ ret = mutex_lock_interruptible(&powercap_mutex);
+ if (ret)
+ goto out_token;
+
+ ret = opal_get_powercap(pcap_attr->handle, token, (u32 *)__pa(&pcap));
+ switch (ret) {
+ case OPAL_ASYNC_COMPLETION:
+ ret = opal_async_wait_response(token, &msg);
+ if (ret) {
+ pr_devel("Failed to wait for the async response\n");
+ ret = -EIO;
+ goto out;
+ }
+ ret = opal_error_code(opal_get_async_rc(msg));
+ if (!ret) {
+ ret = sprintf(buf, "%u\n", be32_to_cpu(pcap));
+ if (ret < 0)
+ ret = -EIO;
+ }
+ break;
+ case OPAL_SUCCESS:
+ ret = sprintf(buf, "%u\n", be32_to_cpu(pcap));
+ if (ret < 0)
+ ret = -EIO;
+ break;
+ default:
+ ret = opal_error_code(ret);
+ }
+
+out:
+ mutex_unlock(&powercap_mutex);
+out_token:
+ opal_async_release_token(token);
+ return ret;
+}
+
+static ssize_t powercap_store(struct kobject *kobj,
+ struct kobj_attribute *attr, const char *buf,
+ size_t count)
+{
+ struct powercap_attr *pcap_attr = container_of(attr,
+ struct powercap_attr, attr);
+ struct opal_msg msg;
+ u32 pcap;
+ int ret, token;
+
+ ret = kstrtoint(buf, 0, &pcap);
+ if (ret)
+ return ret;
+
+ token = opal_async_get_token_interruptible();
+ if (token < 0) {
+ pr_devel("Failed to get token\n");
+ return token;
+ }
+
+ ret = mutex_lock_interruptible(&powercap_mutex);
+ if (ret)
+ goto out_token;
+
+ ret = opal_set_powercap(pcap_attr->handle, token, pcap);
+ switch (ret) {
+ case OPAL_ASYNC_COMPLETION:
+ ret = opal_async_wait_response(token, &msg);
+ if (ret) {
+ pr_devel("Failed to wait for the async response\n");
+ ret = -EIO;
+ goto out;
+ }
+ ret = opal_error_code(opal_get_async_rc(msg));
+ if (!ret)
+ ret = count;
+ break;
+ case OPAL_SUCCESS:
+ ret = count;
+ break;
+ default:
+ ret = opal_error_code(ret);
+ }
+
+out:
+ mutex_unlock(&powercap_mutex);
+out_token:
+ opal_async_release_token(token);
+ return ret;
+}
+
+static void powercap_add_attr(int handle, const char *name,
+ struct powercap_attr *attr)
+{
+ attr->handle = handle;
+ sysfs_attr_init(&attr->attr.attr);
+ attr->attr.attr.name = name;
+ attr->attr.attr.mode = 0444;
+ attr->attr.show = powercap_show;
+}
+
+void __init opal_powercap_init(void)
+{
+ struct device_node *powercap, *node;
+ int i = 0;
+
+ powercap = of_find_compatible_node(NULL, NULL, "ibm,opal-powercap");
+ if (!powercap) {
+ pr_devel("Powercap node not found\n");
+ return;
+ }
+
+ pcaps = kcalloc(of_get_child_count(powercap), sizeof(*pcaps),
+ GFP_KERNEL);
+ if (!pcaps)
+ return;
+
+ powercap_kobj = kobject_create_and_add("powercap", opal_kobj);
+ if (!powercap_kobj) {
+ pr_warn("Failed to create powercap kobject\n");
+ goto out_pcaps;
+ }
+
+ i = 0;
+ for_each_child_of_node(powercap, node) {
+ u32 cur, min, max;
+ int j = 0;
+ bool has_cur = false, has_min = false, has_max = false;
+
+ if (!of_property_read_u32(node, "powercap-min", &min)) {
+ j++;
+ has_min = true;
+ }
+
+ if (!of_property_read_u32(node, "powercap-max", &max)) {
+ j++;
+ has_max = true;
+ }
+
+ if (!of_property_read_u32(node, "powercap-current", &cur)) {
+ j++;
+ has_cur = true;
+ }
+
+ pcaps[i].pattrs = kcalloc(j, sizeof(struct powercap_attr),
+ GFP_KERNEL);
+ if (!pcaps[i].pattrs)
+ goto out_pcaps_pattrs;
+
+ pcaps[i].pg.attrs = kcalloc(j + 1, sizeof(struct attribute *),
+ GFP_KERNEL);
+ if (!pcaps[i].pg.attrs) {
+ kfree(pcaps[i].pattrs);
+ goto out_pcaps_pattrs;
+ }
+
+ j = 0;
+ pcaps[i].pg.name = node->name;
+ if (has_min) {
+ powercap_add_attr(min, "powercap-min",
+ &pcaps[i].pattrs[j]);
+ pcaps[i].pg.attrs[j] = &pcaps[i].pattrs[j].attr.attr;
+ j++;
+ }
+
+ if (has_max) {
+ powercap_add_attr(max, "powercap-max",
+ &pcaps[i].pattrs[j]);
+ pcaps[i].pg.attrs[j] = &pcaps[i].pattrs[j].attr.attr;
+ j++;
+ }
+
+ if (has_cur) {
+ powercap_add_attr(cur, "powercap-current",
+ &pcaps[i].pattrs[j]);
+ pcaps[i].pattrs[j].attr.attr.mode |= 0220;
+ pcaps[i].pattrs[j].attr.store = powercap_store;
+ pcaps[i].pg.attrs[j] = &pcaps[i].pattrs[j].attr.attr;
+ j++;
+ }
+
+ if (sysfs_create_group(powercap_kobj, &pcaps[i].pg)) {
+ pr_warn("Failed to create powercap attribute group
%s\n",
+ pcaps[i].pg.name);
+ goto out_pcaps_pattrs;
+ }
+ i++;
+ }
+
+ return;
+
+out_pcaps_pattrs:
+ while (--i >= 0) {
+ kfree(pcaps[i].pattrs);
+ kfree(pcaps[i].pg.attrs);
+ }
+ kobject_put(powercap_kobj);
+out_pcaps:
+ kfree(pcaps);
+}
diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S
b/arch/powerpc/platforms/powernv/opal-wrappers.S
index 3369a6f..139286c 100644
--- a/arch/powerpc/platforms/powernv/opal-wrappers.S
+++ b/arch/powerpc/platforms/powernv/opal-wrappers.S
@@ -314,3 +314,5 @@ OPAL_CALL(opal_imc_counters_init,
OPAL_IMC_COUNTERS_INIT);
OPAL_CALL(opal_imc_counters_start, OPAL_IMC_COUNTERS_START);
OPAL_CALL(opal_imc_counters_stop, OPAL_IMC_COUNTERS_STOP);
OPAL_CALL(opal_pci_set_p2p, OPAL_PCI_SET_P2P);
+OPAL_CALL(opal_get_powercap, OPAL_GET_POWERCAP);
+OPAL_CALL(opal_set_powercap, OPAL_SET_POWERCAP);
diff --git a/arch/powerpc/platforms/powernv/opal.c
b/arch/powerpc/platforms/powernv/opal.c
index 946158e..28323c7 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -850,6 +850,9 @@ static int __init opal_init(void)
/* Initialise OPAL kmsg dumper for flushing console on panic */
opal_kmsg_init();
+ /* Initialise OPAL powercap interface */
+ opal_powercap_init();
+
return 0;
}
machine_subsys_initcall(powernv, opal_init);
@@ -966,6 +969,7 @@ int opal_error_code(int rc)
case OPAL_UNSUPPORTED: return -EIO;
case OPAL_HARDWARE: return -EIO;
case OPAL_INTERNAL_ERROR: return -EIO;
+ case OPAL_TIMEOUT: return -ETIMEDOUT;
default:
pr_err("%s: unexpected OPAL error %d\n", __func__, rc);
return -EIO;
--
1.8.3.1
