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-rw-r--r--arch/powerpc/include/asm/opal-api.h7
-rw-r--r--arch/powerpc/include/asm/opal.h1
-rw-r--r--arch/powerpc/platforms/powernv/idle.c101
-rw-r--r--arch/powerpc/platforms/powernv/opal-wrappers.S1
4 files changed, 110 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/opal-api.h b/arch/powerpc/include/asm/opal-api.h
index 0321a909e663..a49e5fa6f939 100644
--- a/arch/powerpc/include/asm/opal-api.h
+++ b/arch/powerpc/include/asm/opal-api.h
@@ -165,6 +165,13 @@
#define OPAL_PM_WINKLE_ENABLED 0x00040000
#define OPAL_PM_SLEEP_ENABLED_ER1 0x00080000 /* with workaround */
+/*
+ * OPAL_CONFIG_CPU_IDLE_STATE parameters
+ */
+#define OPAL_CONFIG_IDLE_FASTSLEEP 1
+#define OPAL_CONFIG_IDLE_UNDO 0
+#define OPAL_CONFIG_IDLE_APPLY 1
+
#ifndef __ASSEMBLY__
/* Other enums */
diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
index 042af1abfc4d..9a4781357fa6 100644
--- a/arch/powerpc/include/asm/opal.h
+++ b/arch/powerpc/include/asm/opal.h
@@ -186,6 +186,7 @@ int64_t opal_handle_hmi(void);
int64_t opal_register_dump_region(uint32_t id, uint64_t start, uint64_t end);
int64_t opal_unregister_dump_region(uint32_t id);
int64_t opal_slw_set_reg(uint64_t cpu_pir, uint64_t sprn, uint64_t val);
+int64_t opal_config_cpu_idle_state(uint64_t state, uint64_t flag);
int64_t opal_pci_set_phb_cxl_mode(uint64_t phb_id, uint64_t mode, uint64_t pe_number);
int64_t opal_ipmi_send(uint64_t interface, struct opal_ipmi_msg *msg,
uint64_t msg_len);
diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
index 5c799324b695..bd39a120bd60 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c
@@ -13,6 +13,8 @@
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/of.h>
+#include <linux/device.h>
+#include <linux/cpu.h>
#include <asm/firmware.h>
#include <asm/opal.h>
@@ -137,6 +139,96 @@ u32 pnv_get_supported_cpuidle_states(void)
}
EXPORT_SYMBOL_GPL(pnv_get_supported_cpuidle_states);
+
+static void pnv_fastsleep_workaround_apply(void *info)
+
+{
+ int rc;
+ int *err = info;
+
+ rc = opal_config_cpu_idle_state(OPAL_CONFIG_IDLE_FASTSLEEP,
+ OPAL_CONFIG_IDLE_APPLY);
+ if (rc)
+ *err = 1;
+}
+
+/*
+ * Used to store fastsleep workaround state
+ * 0 - Workaround applied/undone at fastsleep entry/exit path (Default)
+ * 1 - Workaround applied once, never undone.
+ */
+static u8 fastsleep_workaround_applyonce;
+
+static ssize_t show_fastsleep_workaround_applyonce(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%u\n", fastsleep_workaround_applyonce);
+}
+
+static ssize_t store_fastsleep_workaround_applyonce(struct device *dev,
+ struct device_attribute *attr, const char *buf,
+ size_t count)
+{
+ cpumask_t primary_thread_mask;
+ int err;
+ u8 val;
+
+ if (kstrtou8(buf, 0, &val) || val != 1)
+ return -EINVAL;
+
+ if (fastsleep_workaround_applyonce == 1)
+ return count;
+
+ /*
+ * fastsleep_workaround_applyonce = 1 implies
+ * fastsleep workaround needs to be left in 'applied' state on all
+ * the cores. Do this by-
+ * 1. Patching out the call to 'undo' workaround in fastsleep exit path
+ * 2. Sending ipi to all the cores which have atleast one online thread
+ * 3. Patching out the call to 'apply' workaround in fastsleep entry
+ * path
+ * There is no need to send ipi to cores which have all threads
+ * offlined, as last thread of the core entering fastsleep or deeper
+ * state would have applied workaround.
+ */
+ err = patch_instruction(
+ (unsigned int *)pnv_fastsleep_workaround_at_exit,
+ PPC_INST_NOP);
+ if (err) {
+ pr_err("fastsleep_workaround_applyonce change failed while patching pnv_fastsleep_workaround_at_exit");
+ goto fail;
+ }
+
+ get_online_cpus();
+ primary_thread_mask = cpu_online_cores_map();
+ on_each_cpu_mask(&primary_thread_mask,
+ pnv_fastsleep_workaround_apply,
+ &err, 1);
+ put_online_cpus();
+ if (err) {
+ pr_err("fastsleep_workaround_applyonce change failed while running pnv_fastsleep_workaround_apply");
+ goto fail;
+ }
+
+ err = patch_instruction(
+ (unsigned int *)pnv_fastsleep_workaround_at_entry,
+ PPC_INST_NOP);
+ if (err) {
+ pr_err("fastsleep_workaround_applyonce change failed while patching pnv_fastsleep_workaround_at_entry");
+ goto fail;
+ }
+
+ fastsleep_workaround_applyonce = 1;
+
+ return count;
+fail:
+ return -EIO;
+}
+
+static DEVICE_ATTR(fastsleep_workaround_applyonce, 0600,
+ show_fastsleep_workaround_applyonce,
+ store_fastsleep_workaround_applyonce);
+
static int __init pnv_init_idle_states(void)
{
struct device_node *power_mgt;
@@ -181,7 +273,16 @@ static int __init pnv_init_idle_states(void)
patch_instruction(
(unsigned int *)pnv_fastsleep_workaround_at_exit,
PPC_INST_NOP);
+ } else {
+ /*
+ * OPAL_PM_SLEEP_ENABLED_ER1 is set. It indicates that
+ * workaround is needed to use fastsleep. Provide sysfs
+ * control to choose how this workaround has to be applied.
+ */
+ device_create_file(cpu_subsys.dev_root,
+ &dev_attr_fastsleep_workaround_applyonce);
}
+
pnv_alloc_idle_core_states();
out_free:
kfree(flags);
diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S b/arch/powerpc/platforms/powernv/opal-wrappers.S
index a7ade94cdf87..bf15ead00e12 100644
--- a/arch/powerpc/platforms/powernv/opal-wrappers.S
+++ b/arch/powerpc/platforms/powernv/opal-wrappers.S
@@ -283,6 +283,7 @@ OPAL_CALL(opal_sensor_read, OPAL_SENSOR_READ);
OPAL_CALL(opal_get_param, OPAL_GET_PARAM);
OPAL_CALL(opal_set_param, OPAL_SET_PARAM);
OPAL_CALL(opal_handle_hmi, OPAL_HANDLE_HMI);
+OPAL_CALL(opal_config_cpu_idle_state, OPAL_CONFIG_CPU_IDLE_STATE);
OPAL_CALL(opal_slw_set_reg, OPAL_SLW_SET_REG);
OPAL_CALL(opal_register_dump_region, OPAL_REGISTER_DUMP_REGION);
OPAL_CALL(opal_unregister_dump_region, OPAL_UNREGISTER_DUMP_REGION);