From: Johannes Stezenbach <js@xxxxxxxxx>
For the Bay Trail or Cherry Trail SoC to enter the S0i3 power-level
at s2idle suspend requires most of the hw-blocks / devices in the SoC
to be in D3 when entering s2idle suspend.
If some devices are not in D3 then the SoC will stay in a higher
power state, consuming much more power from the battery then in S0i3.
Use the new acpi_s2idle_dev_ops and acpi_register_lps0_dev()
functionality to register a new s2idle check function which checks that
all hardware blocks in theNorth complex (controlled by Punit) are in
a state that allows the SoC to enter S0i3 and prints an error message
for any device in D0.
Signed-off-by: Johannes Stezenbach <js@xxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Acked-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
[hdegoede: Use acpi_s2idle_dev_ops]
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
Changes in v3:
- Reword commit message
- Add punit_s2idle_check_[un]register() helper functions
---
arch/x86/platform/atom/punit_atom_debug.c | 54 ++++++++++++++++++++++-
1 file changed, 53 insertions(+), 1 deletion(-)
diff --git a/arch/x86/platform/atom/punit_atom_debug.c b/arch/x86/platform/atom/punit_atom_debug.c
index f8ed5f66cd20..6b9c6deca8ba 100644
--- a/arch/x86/platform/atom/punit_atom_debug.c
+++ b/arch/x86/platform/atom/punit_atom_debug.c
@@ -7,6 +7,9 @@
* Copyright (c) 2015, Intel Corporation.
*/
+#define pr_fmt(fmt) "punit_atom: " fmt
+
+#include <linux/acpi.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
@@ -117,6 +120,51 @@ static void punit_dbgfs_unregister(void)
debugfs_remove_recursive(punit_dbg_file);
}
+#if defined(CONFIG_ACPI) && defined(CONFIG_SUSPEND)
+static const struct punit_device *punit_dev;
+
+static void punit_s2idle_check(void)
+{
+ const struct punit_device *punit_devp;
+ u32 punit_pwr_status, dstate;
+ int status;
+
+ for (punit_devp = punit_dev; punit_devp->name; punit_devp++) {
+ /* Skip MIO, it is on till the very last moment */
+ if (punit_devp->reg == MIO_SS_PM)
+ continue;
+
+ status = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ,
+ punit_devp->reg, &punit_pwr_status);
+ if (status) {
+ pr_err("%s read failed\n", punit_devp->name);
+ } else {
+ dstate = (punit_pwr_status >> punit_devp->sss_pos) & 3;
+ if (!dstate)
+ pr_err("%s is in D0 prior to s2idle\n", punit_devp->name);
+ }
+ }
+}
+
+static struct acpi_s2idle_dev_ops punit_s2idle_ops = {
+ .check = punit_s2idle_check,
+};
+
+static void punit_s2idle_check_register(struct punit_device *punit_device)
+{
+ punit_dev = punit_device;
+ acpi_register_lps0_dev(&punit_s2idle_ops);
+}
+
+static void punit_s2idle_check_unregister(void)
+{
+ acpi_unregister_lps0_dev(&punit_s2idle_ops);
+}
+#else
+static void punit_s2idle_check_register(struct punit_device *punit_device) {}
+static void punit_s2idle_check_unregister(void) {}
+#endif
+
#define X86_MATCH(model, data) \
X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, INTEL_FAM6_##model, \
X86_FEATURE_MWAIT, data)
@@ -131,19 +179,23 @@ MODULE_DEVICE_TABLE(x86cpu, intel_punit_cpu_ids);
static int __init punit_atom_debug_init(void)
{
+ struct punit_device *punit_device;
const struct x86_cpu_id *id;
id = x86_match_cpu(intel_punit_cpu_ids);
if (!id)
return -ENODEV;
- punit_dbgfs_register((struct punit_device *)id->driver_data);
+ punit_device = (struct punit_device *)id->driver_data;
+ punit_dbgfs_register(punit_device);
+ punit_s2idle_check_register(punit_device);
return 0;
}
static void __exit punit_atom_debug_exit(void)
{
+ punit_s2idle_check_unregister();
punit_dbgfs_unregister();
}
--
2.43.0
