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 the South complex (controlled by the PMC)
are in a state that allows the SoC to enter S0i3 and prints an error
message for any device in D0.
Some blocks are not used on lower-featured versions of the SoC and
these blocks will always report being in D0 on SoCs were they are
not used. A false-positive mask is used to identify these blocks
and for blocks in this mask the error is turned into a debug message
to avoid false-positive error messages.
Note the pmc_atom code is enabled by CONFIG_X86_INTEL_LPSS which
already depends on ACPI.
Signed-off-by: Johannes Stezenbach <js@xxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
[hdegoede: Use acpi_s2idle_dev_ops, ignore fused off blocks, PMIC I2C]
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
Changes in v3:
- Reword commit message
- Drop confusing /* Low Part */ and /* High Part */ comments
Changes in v2:
- Drop duplicated "pmc_atom: " prefix from pr_err() / pr_dbg() messages
---
drivers/platform/x86/pmc_atom.c | 64 +++++++++++++++++++++++++++++++++
1 file changed, 64 insertions(+)
diff --git a/drivers/platform/x86/pmc_atom.c b/drivers/platform/x86/pmc_atom.c
index 93a6414c6611..ec60b734b9cb 100644
--- a/drivers/platform/x86/pmc_atom.c
+++ b/drivers/platform/x86/pmc_atom.c
@@ -6,6 +6,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/acpi.h>
#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/dmi.h>
@@ -17,6 +18,7 @@
#include <linux/platform_device.h>
#include <linux/pci.h>
#include <linux/seq_file.h>
+#include <linux/suspend.h>
struct pmc_bit_map {
const char *name;
@@ -448,6 +450,64 @@ static int pmc_setup_clks(struct pci_dev *pdev, void __iomem *pmc_regmap,
return 0;
}
+#ifdef CONFIG_SUSPEND
+static void pmc_dev_state_check(u32 sts, const struct pmc_bit_map *sts_map,
+ u32 fd, const struct pmc_bit_map *fd_map,
+ u32 sts_possible_false_pos)
+{
+ int index;
+
+ for (index = 0; sts_map[index].name; index++) {
+ if (!(fd_map[index].bit_mask & fd) &&
+ !(sts_map[index].bit_mask & sts)) {
+ if (sts_map[index].bit_mask & sts_possible_false_pos)
+ pm_pr_dbg("%s is in D0 prior to s2idle\n",
+ sts_map[index].name);
+ else
+ pr_err("%s is in D0 prior to s2idle\n",
+ sts_map[index].name);
+ }
+ }
+}
+
+static void pmc_s2idle_check(void)
+{
+ struct pmc_dev *pmc = &pmc_device;
+ const struct pmc_reg_map *m = pmc->map;
+ u32 func_dis, func_dis_2;
+ u32 d3_sts_0, d3_sts_1;
+ u32 false_pos_sts_0, false_pos_sts_1;
+
+ func_dis = pmc_reg_read(pmc, PMC_FUNC_DIS);
+ func_dis_2 = pmc_reg_read(pmc, PMC_FUNC_DIS_2);
+ d3_sts_0 = pmc_reg_read(pmc, PMC_D3_STS_0);
+ d3_sts_1 = pmc_reg_read(pmc, PMC_D3_STS_1);
+
+ /*
+ * Some blocks are not used on lower-featured versions of the SoC and
+ * always report D0, add these to false_pos mask to log at debug level.
+ */
+ if (m->d3_sts_1 == byt_d3_sts_1_map) {
+ /* Bay Trail */
+ false_pos_sts_0 = BIT_GBE | BIT_SATA | BIT_PCIE_PORT0 |
+ BIT_PCIE_PORT1 | BIT_PCIE_PORT2 | BIT_PCIE_PORT3 |
+ BIT_LPSS2_F5_I2C5;
+ false_pos_sts_1 = BIT_SMB | BIT_USH_SS_PHY | BIT_DFX;
+ } else {
+ /* Cherry Trail */
+ false_pos_sts_0 = BIT_GBE | BIT_SATA | BIT_LPSS2_F7_I2C7;
+ false_pos_sts_1 = BIT_SMB | BIT_STS_ISH;
+ }
+
+ pmc_dev_state_check(d3_sts_0, m->d3_sts_0, func_dis, m->func_dis, false_pos_sts_0);
+ pmc_dev_state_check(d3_sts_1, m->d3_sts_1, func_dis_2, m->func_dis_2, false_pos_sts_1);
+}
+
+static struct acpi_s2idle_dev_ops pmc_s2idle_ops = {
+ .check = pmc_s2idle_check,
+};
+#endif
+
static int pmc_setup_dev(struct pci_dev *pdev, const struct pci_device_id *ent)
{
struct pmc_dev *pmc = &pmc_device;
@@ -485,6 +545,10 @@ static int pmc_setup_dev(struct pci_dev *pdev, const struct pci_device_id *ent)
dev_warn(&pdev->dev, "platform clocks register failed: %d\n",
ret);
+#ifdef CONFIG_SUSPEND
+ acpi_register_lps0_dev(&pmc_s2idle_ops);
+#endif
+
pmc->init = true;
return ret;
}
--
2.43.0
