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authorTony Lindgren <tony@atomide.com>2016-03-30 10:36:06 -0700
committerTony Lindgren <tony@atomide.com>2016-03-30 10:36:06 -0700
commit1809de7e7d37c585e01a1bcc583ea92b78fc759d (patch)
tree76c5b35c2b04eafce86a1a729c02ab705eba44bc /drivers/firmware/psci.c
parentebf24414809200915b9ddf7f109bba7c278c8210 (diff)
parent3ca4a238106dedc285193ee47f494a6584b6fd2f (diff)
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Merge tag 'for-v4.6-rc/omap-fixes-a' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v4.6/fixes
ARM: OMAP2+: first hwmod fix for v4.6-rc Fix a longstanding bug in the hwmod code that could cause hardware SYSCONFIG register values to not match the kernel's idea of what they should be, and that could result in lower performance during IP block idle entry. Basic build, boot, and PM test logs are available here: http://www.pwsan.com/omap/testlogs/omap-hwmod-fixes-a-for-v4.6-rc/20160326231727/
Diffstat (limited to 'drivers/firmware/psci.c')
-rw-r--r--drivers/firmware/psci.c120
1 files changed, 120 insertions, 0 deletions
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
index f25cd79c8a79..11bfee8b79a9 100644
--- a/drivers/firmware/psci.c
+++ b/drivers/firmware/psci.c
@@ -14,6 +14,7 @@
#define pr_fmt(fmt) "psci: " fmt
#include <linux/arm-smccc.h>
+#include <linux/cpuidle.h>
#include <linux/errno.h>
#include <linux/linkage.h>
#include <linux/of.h>
@@ -21,10 +22,12 @@
#include <linux/printk.h>
#include <linux/psci.h>
#include <linux/reboot.h>
+#include <linux/slab.h>
#include <linux/suspend.h>
#include <uapi/linux/psci.h>
+#include <asm/cpuidle.h>
#include <asm/cputype.h>
#include <asm/system_misc.h>
#include <asm/smp_plat.h>
@@ -244,6 +247,123 @@ static int __init psci_features(u32 psci_func_id)
psci_func_id, 0, 0);
}
+#ifdef CONFIG_CPU_IDLE
+static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
+
+static int psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu)
+{
+ int i, ret, count = 0;
+ u32 *psci_states;
+ struct device_node *state_node;
+
+ /*
+ * If the PSCI cpu_suspend function hook has not been initialized
+ * idle states must not be enabled, so bail out
+ */
+ if (!psci_ops.cpu_suspend)
+ return -EOPNOTSUPP;
+
+ /* Count idle states */
+ while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
+ count))) {
+ count++;
+ of_node_put(state_node);
+ }
+
+ if (!count)
+ return -ENODEV;
+
+ psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
+ if (!psci_states)
+ return -ENOMEM;
+
+ for (i = 0; i < count; i++) {
+ u32 state;
+
+ state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
+
+ ret = of_property_read_u32(state_node,
+ "arm,psci-suspend-param",
+ &state);
+ if (ret) {
+ pr_warn(" * %s missing arm,psci-suspend-param property\n",
+ state_node->full_name);
+ of_node_put(state_node);
+ goto free_mem;
+ }
+
+ of_node_put(state_node);
+ pr_debug("psci-power-state %#x index %d\n", state, i);
+ if (!psci_power_state_is_valid(state)) {
+ pr_warn("Invalid PSCI power state %#x\n", state);
+ ret = -EINVAL;
+ goto free_mem;
+ }
+ psci_states[i] = state;
+ }
+ /* Idle states parsed correctly, initialize per-cpu pointer */
+ per_cpu(psci_power_state, cpu) = psci_states;
+ return 0;
+
+free_mem:
+ kfree(psci_states);
+ return ret;
+}
+
+int psci_cpu_init_idle(unsigned int cpu)
+{
+ struct device_node *cpu_node;
+ int ret;
+
+ cpu_node = of_get_cpu_node(cpu, NULL);
+ if (!cpu_node)
+ return -ENODEV;
+
+ ret = psci_dt_cpu_init_idle(cpu_node, cpu);
+
+ of_node_put(cpu_node);
+
+ return ret;
+}
+
+static int psci_suspend_finisher(unsigned long index)
+{
+ u32 *state = __this_cpu_read(psci_power_state);
+
+ return psci_ops.cpu_suspend(state[index - 1],
+ virt_to_phys(cpu_resume));
+}
+
+int psci_cpu_suspend_enter(unsigned long index)
+{
+ int ret;
+ u32 *state = __this_cpu_read(psci_power_state);
+ /*
+ * idle state index 0 corresponds to wfi, should never be called
+ * from the cpu_suspend operations
+ */
+ if (WARN_ON_ONCE(!index))
+ return -EINVAL;
+
+ if (!psci_power_state_loses_context(state[index - 1]))
+ ret = psci_ops.cpu_suspend(state[index - 1], 0);
+ else
+ ret = cpu_suspend(index, psci_suspend_finisher);
+
+ return ret;
+}
+
+/* ARM specific CPU idle operations */
+#ifdef CONFIG_ARM
+static struct cpuidle_ops psci_cpuidle_ops __initdata = {
+ .suspend = psci_cpu_suspend_enter,
+ .init = psci_dt_cpu_init_idle,
+};
+
+CPUIDLE_METHOD_OF_DECLARE(psci, "arm,psci", &psci_cpuidle_ops);
+#endif
+#endif
+
static int psci_system_suspend(unsigned long unused)
{
return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
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