[PATCH 1/2] scsi: ufs: ufs-pci: Add support for Intel UFS 4.0 HS-Gear5

[sangram kumar yerra]

Reliable HS-Gear5 operation on Intel UFS 4.0 controllers requires
configuring PA_INITIAL_ADAPT before changing the power mode. Without
this setting, the link fails to train reliably at Gear5.

Add a pwr_change_notify() hook to configure the adaptation mode before
the power mode transition. Enable this only for UFS 4.0 and later
controllers by checking hba->ufs_version.

Wire the hook into the existing Meteor Lake family variant operations
table (ufs_intel_mtl_hba_vops) instead of introducing a separate table,
since the Intel UFS 4.0 PCI variant (PCI ID 8086:D335) already uses
this vops table and the hook is internally gated on UFS version >= 4.0.

Use PA_INITIAL_ADAPT when the negotiated TX power mode is FAST_MODE or
FASTAUTO_MODE. Otherwise, reset the adaptation mode to PA_NO_ADAPT,
which is the default setting.

Fixes: 096cd6b7adf2 ("scsi: ufs: ufs-pci: Add support for Intel Nova Lake")
Signed-off-by: sangram kumar yerra <sangram.k.y@xxxxxxxxx>
Reviewed-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
 drivers/ufs/host/ufshcd-pci.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/ufs/host/ufshcd-pci.c b/drivers/ufs/host/ufshcd-pci.c
index f2433879b0eb..93bfafc25018 100644
--- a/drivers/ufs/host/ufshcd-pci.c
+++ b/drivers/ufs/host/ufshcd-pci.c
@@ -181,6 +181,25 @@ static int ufs_intel_lkf_pwr_change_notify(struct ufs_hba *hba,
 	return err;
 }
 
+static int ufs_intel_nvl_pwr_change_notify(struct ufs_hba *hba,
+					   enum ufs_notify_change_status stage,
+					   struct ufs_pa_layer_attr *dev_req_params)
+{
+	int adapt_val;
+
+	if (stage != PRE_CHANGE || hba->ufs_version < ufshci_version(4, 0))
+		return 0;
+
+	if (dev_req_params->pwr_tx == FAST_MODE || dev_req_params->pwr_tx == FASTAUTO_MODE)
+		adapt_val = PA_INITIAL_ADAPT;
+	else
+		adapt_val = PA_NO_ADAPT;
+
+	ufshcd_dme_configure_adapt(hba, dev_req_params->gear_tx, adapt_val);
+
+	return 0;
+}
+
 static int ufs_intel_lkf_apply_dev_quirks(struct ufs_hba *hba)
 {
 	u32 granularity, peer_granularity;
@@ -527,6 +546,7 @@ static struct ufs_hba_variant_ops ufs_intel_mtl_hba_vops = {
 	.exit			= ufs_intel_common_exit,
 	.hce_enable_notify	= ufs_intel_hce_enable_notify,
 	.link_startup_notify	= ufs_intel_link_startup_notify,
+	.pwr_change_notify	= ufs_intel_nvl_pwr_change_notify,
 	.resume			= ufs_intel_resume,
 	.device_reset		= ufs_intel_device_reset,
 };
-- 
2.34.1