To improve the r/w performance of GL9763E, the current driver inhibits LPM
negotiation while the device is active.
This prevents a large number of SoCs from suspending, notably x86 systems
which commonly use S0ix as the suspend mechanism - for example, Intel
Alder Lake and Raptor Lake processors.
Failure description:
1. Userspace initiates s2idle suspend (e.g. via writing to
/sys/power/state)
2. This switches the runtime_pm device state to active, which disables
LPM negotiation, then calls the "regular" suspend callback
3. With LPM negotiation disabled, the bus cannot enter low-power state
4. On a large number of SoCs, if the bus not in a low-power state, S0ix
cannot be entered, which in turn prevents the SoC from entering
suspend.
Fix by re-enabling LPM negotiation in the device's suspend callback.
Suggested-by: Stanislaw Kardach <skardach@xxxxxxxxxx>
Fixes: f9e5b33934ce ("mmc: host: Improve I/O read/write performance for GL9763E")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Sven van Ashbrook <svenva@xxxxxxxxxxxx>
---
Changes in v3:
- applied maintainer feedback from https://lore.kernel.org/lkml/CACT4zj-BaX4tHji8B8gS5jiKkd-2BcwfzHM4fS-OUn0f8DSxcw@xxxxxxxxxxxxxx/T/#m7cea7b6b987d1ab1ca95feedf2c6f9da5783da5c
Changes in v2:
- improved symmetry and error path in s2idle suspend callback (internal review)
drivers/mmc/host/sdhci-pci-gli.c | 104 ++++++++++++++++++++-----------
1 file changed, 66 insertions(+), 38 deletions(-)
diff --git a/drivers/mmc/host/sdhci-pci-gli.c b/drivers/mmc/host/sdhci-pci-gli.c
index 1792665c9494a..a4ccb6c3e27a6 100644
--- a/drivers/mmc/host/sdhci-pci-gli.c
+++ b/drivers/mmc/host/sdhci-pci-gli.c
@@ -745,42 +745,6 @@ static u32 sdhci_gl9750_readl(struct sdhci_host *host, int reg)
return value;
}
-#ifdef CONFIG_PM_SLEEP
-static int sdhci_pci_gli_resume(struct sdhci_pci_chip *chip)
-{
- struct sdhci_pci_slot *slot = chip->slots[0];
-
- pci_free_irq_vectors(slot->chip->pdev);
- gli_pcie_enable_msi(slot);
-
- return sdhci_pci_resume_host(chip);
-}
-
-static int sdhci_cqhci_gli_resume(struct sdhci_pci_chip *chip)
-{
- struct sdhci_pci_slot *slot = chip->slots[0];
- int ret;
-
- ret = sdhci_pci_gli_resume(chip);
- if (ret)
- return ret;
-
- return cqhci_resume(slot->host->mmc);
-}
-
-static int sdhci_cqhci_gli_suspend(struct sdhci_pci_chip *chip)
-{
- struct sdhci_pci_slot *slot = chip->slots[0];
- int ret;
-
- ret = cqhci_suspend(slot->host->mmc);
- if (ret)
- return ret;
-
- return sdhci_suspend_host(slot->host);
-}
-#endif
-
static void gl9763e_hs400_enhanced_strobe(struct mmc_host *mmc,
struct mmc_ios *ios)
{
@@ -1029,6 +993,70 @@ static int gl9763e_runtime_resume(struct sdhci_pci_chip *chip)
}
#endif
+#ifdef CONFIG_PM_SLEEP
+static int sdhci_pci_gli_resume(struct sdhci_pci_chip *chip)
+{
+ struct sdhci_pci_slot *slot = chip->slots[0];
+
+ pci_free_irq_vectors(slot->chip->pdev);
+ gli_pcie_enable_msi(slot);
+
+ return sdhci_pci_resume_host(chip);
+}
+
+static int gl9763e_resume(struct sdhci_pci_chip *chip)
+{
+ struct sdhci_pci_slot *slot = chip->slots[0];
+ int ret;
+
+ ret = sdhci_pci_gli_resume(chip);
+ if (ret)
+ return ret;
+
+ ret = cqhci_resume(slot->host->mmc);
+ if (ret)
+ return ret;
+
+ /*
+ * Disable LPM negotiation to bring device back in sync
+ * with its runtime_pm state.
+ */
+ gl9763e_set_low_power_negotiation(slot, false);
+
+ return 0;
+}
+
+static int gl9763e_suspend(struct sdhci_pci_chip *chip)
+{
+ struct sdhci_pci_slot *slot = chip->slots[0];
+ int ret;
+
+ /*
+ * Certain SoCs can suspend only with the bus in low-
+ * power state, notably x86 SoCs when using S0ix.
+ * Re-enable LPM negotiation to allow entering L1 state
+ * and entering system suspend.
+ */
+ gl9763e_set_low_power_negotiation(slot, true);
+
+ ret = cqhci_suspend(slot->host->mmc);
+ if (ret)
+ goto err_suspend;
+
+ ret = sdhci_suspend_host(slot->host);
+ if (ret)
+ goto err_suspend_host;
+
+ return 0;
+
+err_suspend_host:
+ cqhci_resume(slot->host->mmc);
+err_suspend:
+ gl9763e_set_low_power_negotiation(slot, false);
+ return ret;
+}
+#endif
+
static int gli_probe_slot_gl9763e(struct sdhci_pci_slot *slot)
{
struct pci_dev *pdev = slot->chip->pdev;
@@ -1113,8 +1141,8 @@ const struct sdhci_pci_fixes sdhci_gl9763e = {
.probe_slot = gli_probe_slot_gl9763e,
.ops = &sdhci_gl9763e_ops,
#ifdef CONFIG_PM_SLEEP
- .resume = sdhci_cqhci_gli_resume,
- .suspend = sdhci_cqhci_gli_suspend,
+ .resume = gl9763e_resume,
+ .suspend = gl9763e_suspend,
#endif
#ifdef CONFIG_PM
.runtime_suspend = gl9763e_runtime_suspend,
--
2.42.0.283.g2d96d420d3-goog
