[PATCH v8 15/17] scsi: ufs-qcom: set PA_Local_TX_LCC_Enable before link startup

From: Yaniv Gardi
Date: Thu Mar 10 2016 - 10:38:58 EST


Some UFS devices (and may be host) have issues if LCC is
enabled. So we are setting PA_Local_TX_LCC_Enable to 0
before link startup which will make sure that both host
and device TX LCC are disabled once link startup is
completed.

Reviewed-by: Gilad Broner <gbroner@xxxxxxxxxxxxxx>
Signed-off-by: Yaniv Gardi <ygardi@xxxxxxxxxxxxxx>

---
drivers/scsi/ufs/ufs-qcom.c | 27 ++++++++++++++++++++-------
drivers/scsi/ufs/unipro.h | 1 +
2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index ed57729..966bacf 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -16,8 +16,8 @@
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/phy/phy.h>
-
#include <linux/phy/phy-qcom-ufs.h>
+
#include "ufshcd.h"
#include "ufshcd-pltfrm.h"
#include "unipro.h"
@@ -106,9 +106,11 @@ static void ufs_qcom_disable_lane_clks(struct ufs_qcom_host *host)
if (!host->is_lane_clks_enabled)
return;

- clk_disable_unprepare(host->tx_l1_sync_clk);
+ if (host->hba->lanes_per_direction > 1)
+ clk_disable_unprepare(host->tx_l1_sync_clk);
clk_disable_unprepare(host->tx_l0_sync_clk);
- clk_disable_unprepare(host->rx_l1_sync_clk);
+ if (host->hba->lanes_per_direction > 1)
+ clk_disable_unprepare(host->rx_l1_sync_clk);
clk_disable_unprepare(host->rx_l0_sync_clk);

host->is_lane_clks_enabled = false;
@@ -272,9 +274,8 @@ static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
ret = ufs_qcom_phy_calibrate_phy(phy, is_rate_B);

if (ret) {
- dev_err(hba->dev,
- "%s: ufs_qcom_phy_calibrate_phy()failed, ret = %d\n",
- __func__, ret);
+ dev_err(hba->dev, "%s: ufs_qcom_phy_calibrate_phy() failed, ret = %d\n",
+ __func__, ret);
goto out;
}

@@ -524,6 +525,18 @@ static int ufs_qcom_link_startup_notify(struct ufs_hba *hba,
err = ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(hba,
150);

+ /*
+ * Some UFS devices (and may be host) have issues if LCC is
+ * enabled. So we are setting PA_Local_TX_LCC_Enable to 0
+ * before link startup which will make sure that both host
+ * and device TX LCC are disabled once link startup is
+ * completed.
+ */
+ if (ufshcd_get_local_unipro_ver(hba) != UFS_UNIPRO_VER_1_41)
+ err = ufshcd_dme_set(hba,
+ UIC_ARG_MIB(PA_LOCAL_TX_LCC_ENABLE),
+ 0);
+
break;
case POST_CHANGE:
ufs_qcom_link_startup_post_change(hba);
@@ -1542,7 +1555,7 @@ static int ufs_qcom_probe(struct platform_device *pdev)
* ufs_qcom_remove - set driver_data of the device to NULL
* @pdev: pointer to platform device handle
*
- * Always return 0
+ * Always returns 0
*/
static int ufs_qcom_remove(struct platform_device *pdev)
{
diff --git a/drivers/scsi/ufs/unipro.h b/drivers/scsi/ufs/unipro.h
index 8082020..e2854e4 100644
--- a/drivers/scsi/ufs/unipro.h
+++ b/drivers/scsi/ufs/unipro.h
@@ -75,6 +75,7 @@
#define PA_MAXRXSPEEDFAST 0x1541
#define PA_MAXRXSPEEDSLOW 0x1542
#define PA_TXLINKSTARTUPHS 0x1544
+#define PA_LOCAL_TX_LCC_ENABLE 0x155E
#define PA_TXSPEEDFAST 0x1565
#define PA_TXSPEEDSLOW 0x1566
#define PA_REMOTEVERINFO 0x15A0
--
1.8.5.2

--
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