[PATCH v5 03/16] ufs: core: Introduce Multi-circular queue capability

[Asutosh Das <quic_asutoshd@quicinc.com>]

Add support to check for MCQ capability in the UFSHC.
Add a module parameter to disable MCQ if needed.

Co-developed-by: Can Guo <quic_cang@quicinc.com>
Signed-off-by: Can Guo <quic_cang@quicinc.com>
Signed-off-by: Asutosh Das <quic_asutoshd@quicinc.com>
---
 drivers/ufs/core/ufshcd.c | 31 +++++++++++++++++++++++++++++++
 include/ufs/ufshcd.h      |  2 ++
 2 files changed, 33 insertions(+)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 66b797f..08be8ad 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -89,6 +89,33 @@
 /* Polling time to wait for fDeviceInit */
 #define FDEVICEINIT_COMPL_TIMEOUT 1500 /* millisecs */
 
+/* UFSHC 4.0 compliant HC support this mode, refer param_set_mcq_mode() */
+static bool use_mcq_mode = true;
+
+static inline bool is_mcq_supported(struct ufs_hba *hba)
+{
+	return hba->mcq_sup && use_mcq_mode;
+}
+
+static int param_set_mcq_mode(const char *val, const struct kernel_param *kp)
+{
+	int ret;
+
+	ret = param_set_bool(val, kp);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static const struct kernel_param_ops mcq_mode_ops = {
+	.set = param_set_mcq_mode,
+	.get = param_get_bool,
+};
+
+module_param_cb(use_mcq_mode, &mcq_mode_ops, &use_mcq_mode, 0644);
+MODULE_PARM_DESC(mcq_mode, "Control MCQ mode for UFSHCI 4.0 controllers");
+
 #define ufshcd_toggle_vreg(_dev, _vreg, _on)				\
 	({                                                              \
 		int _ret;                                               \
@@ -2258,6 +2285,10 @@ static inline int ufshcd_hba_capabilities(struct ufs_hba *hba)
 	if (err)
 		dev_err(hba->dev, "crypto setup failed\n");
 
+	hba->mcq_sup = FIELD_GET(MASK_MCQ_SUPPORT, hba->capabilities);
+	if (!hba->mcq_sup)
+		return err;
+
 	hba->mcq_capabilities = ufshcd_readl(hba, REG_MCQCAP);
 	hba->ext_iid_sup = FIELD_GET(MASK_EXT_IID_SUPPORT,
 				     hba->mcq_capabilities);
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index aec37cb9..70c0f9f 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -832,6 +832,7 @@ struct ufs_hba_monitor {
  * @complete_put: whether or not to call ufshcd_rpm_put() from inside
  *	ufshcd_resume_complete()
  * @ext_iid_sup: is EXT_IID is supported by UFSHC
+ * @mcq_sup: is mcq supported by UFSHC
  */
 struct ufs_hba {
 	void __iomem *mmio_base;
@@ -982,6 +983,7 @@ struct ufs_hba {
 	u32 luns_avail;
 	bool complete_put;
 	bool ext_iid_sup;
+	bool mcq_sup;
 };
 
 /* Returns true if clocks can be gated. Otherwise false */
-- 
2.7.4