[PATCH v2 1/1] scsi: ufs: Add hibernation callbacks

[Anjana Hari]

Adds freeze, thaw and restore callbacks for hibernate and restore
functionality.

Signed-off-by: Anjana Hari <quic_ahari@xxxxxxxxxxx>
---
 drivers/ufs/core/ufshcd.c   | 60 +++++++++++++++++++++++++++++++++++++
 drivers/ufs/host/ufs-qcom.c |  6 +++-
 include/ufs/ufshcd.h        |  8 +++++
 3 files changed, 73 insertions(+), 1 deletion(-)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index fcd46251f7a8..bc0d47570c59 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -9826,11 +9826,36 @@ static int ufshcd_resume(struct ufs_hba *hba)
 
 	/* enable the host irq as host controller would be active soon */
 	ufshcd_enable_irq(hba);
+
+	if (hba->restore) {
+		/* Configure UTRL and UTMRL base address registers */
+		ufshcd_writel(hba, lower_32_bits(hba->utrdl_dma_addr),
+			      REG_UTP_TRANSFER_REQ_LIST_BASE_L);
+		ufshcd_writel(hba, upper_32_bits(hba->utrdl_dma_addr),
+			      REG_UTP_TRANSFER_REQ_LIST_BASE_H);
+		ufshcd_writel(hba, lower_32_bits(hba->utmrdl_dma_addr),
+			      REG_UTP_TASK_REQ_LIST_BASE_L);
+		ufshcd_writel(hba, upper_32_bits(hba->utmrdl_dma_addr),
+			      REG_UTP_TASK_REQ_LIST_BASE_H);
+		/* Make sure that UTRL and UTMRL base address registers
+		 * are updated with the latest queue addresses. Only after
+		 * updating these addresses, we can queue the new commands.
+		 */
+		mb();
+	}
+
+	/* Resuming from hibernate, assume that link was OFF */
+	if (hba->restore)
+		ufshcd_set_link_off(hba);
+
 	goto out;
 
 disable_vreg:
 	ufshcd_vreg_set_lpm(hba);
 out:
+	if (hba->restore)
+		hba->restore = false;
+
 	if (ret)
 		ufshcd_update_evt_hist(hba, UFS_EVT_RESUME_ERR, (u32)ret);
 	return ret;
@@ -9989,6 +10014,41 @@ void ufshcd_remove(struct ufs_hba *hba)
 }
 EXPORT_SYMBOL_GPL(ufshcd_remove);
 
+int ufshcd_system_freeze(struct device *dev)
+{
+
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+	int ret = 0;
+
+	/*
+	 * Run time resume the controller to make sure
+	 * the PM work queue threads do not try to resume
+	 * the child (scsi host), which leads to errors as
+	 * the controller is not yet resumed.
+	 */
+	pm_runtime_get_sync(hba->dev);
+	ret = ufshcd_system_suspend(dev);
+	pm_runtime_put_sync(hba->dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ufshcd_system_freeze);
+
+int ufshcd_system_restore(struct device *dev)
+{
+
+	hba->restore = true;
+	return ufshcd_system_resume(dev);
+
+}
+EXPORT_SYMBOL_GPL(ufshcd_system_restore);
+
+int ufshcd_system_thaw(struct device *dev)
+{
+	return ufshcd_system_resume(dev);
+}
+EXPORT_SYMBOL_GPL(ufshcd_system_thaw);
+
 /**
  * ufshcd_dealloc_host - deallocate Host Bus Adapter (HBA)
  * @hba: pointer to Host Bus Adapter (HBA)
diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
index 681da3ea7154..c92e041c5361 100644
--- a/drivers/ufs/host/ufs-qcom.c
+++ b/drivers/ufs/host/ufs-qcom.c
@@ -1714,10 +1714,14 @@ MODULE_DEVICE_TABLE(acpi, ufs_qcom_acpi_match);
 #endif
 
 static const struct dev_pm_ops ufs_qcom_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(ufshcd_system_suspend, ufshcd_system_resume)
 	SET_RUNTIME_PM_OPS(ufshcd_runtime_suspend, ufshcd_runtime_resume, NULL)
 	.prepare	 = ufshcd_suspend_prepare,
 	.complete	 = ufshcd_resume_complete,
+	.suspend         = ufshcd_system_suspend,
+	.resume          = ufshcd_system_resume,
+	.freeze          = ufshcd_system_freeze,
+	.restore         = ufshcd_system_restore,
+	.thaw            = ufshcd_system_thaw,
 };
 
 static struct platform_driver ufs_qcom_pltform = {
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index 1779238d8a56..6f50390ca262 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -1071,6 +1071,9 @@ struct ufs_hba {
 	struct ufs_hw_queue *uhq;
 	struct ufs_hw_queue *dev_cmd_queue;
 	struct ufshcd_mcq_opr_info_t mcq_opr[OPR_MAX];
+
+	/* Distinguish between resume and restore */
+	bool restore;
 };
 
 /**
@@ -1278,6 +1281,11 @@ extern int ufshcd_system_suspend(struct device *dev);
 extern int ufshcd_system_resume(struct device *dev);
 #endif
 extern int ufshcd_shutdown(struct ufs_hba *hba);
+
+extern int ufshcd_system_freeze(struct device *dev);
+extern int ufshcd_system_thaw(struct device *dev);
+extern int ufshcd_system_restore(struct device *dev);
+
 extern int ufshcd_dme_configure_adapt(struct ufs_hba *hba,
 				      int agreed_gear,
 				      int adapt_val);
-- 
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