[RFC/RFT 3/5] phy: exynos5-usbdrd: UTMI tune signal

From: Anand Moon
Date: Mon Jul 22 2019 - 15:00:01 EST


Tune USB2.0 (UTMI+) TX signal for high speed data transfer.

Signed-off-by: Anand Moon <linux.amoon@xxxxxxxxx>
---
drivers/phy/samsung/phy-exynos5-usbdrd.c | 42 +++++++++++++++++++++---
1 file changed, 37 insertions(+), 5 deletions(-)

diff --git a/drivers/phy/samsung/phy-exynos5-usbdrd.c b/drivers/phy/samsung/phy-exynos5-usbdrd.c
index 135114d51bc1..54a513ca15e4 100644
--- a/drivers/phy/samsung/phy-exynos5-usbdrd.c
+++ b/drivers/phy/samsung/phy-exynos5-usbdrd.c
@@ -33,6 +33,8 @@
#define EXYNOS5_FSEL_24MHZ 0x5
#define EXYNOS5_FSEL_50MHZ 0x7

+#define __set(v, a, b) (((v) << (b)) & GENMASK(a, b))
+
/* EXYNOS5: USB 3.0 DRD PHY registers */
#define EXYNOS5_DRD_LINKSYSTEM 0x04

@@ -108,8 +110,17 @@
#define EXYNOS5_DRD_PHYPARAM0 0x1c

#define PHYPARAM0_REF_USE_PAD BIT(31)
-#define PHYPARAM0_REF_LOSLEVEL_MASK (0x1f << 26)
-#define PHYPARAM0_REF_LOSLEVEL (0x9 << 26)
+#define PHYPARAM0_REF_LOSLEVEL(x) __set(x, 30, 26)
+#define PHYPARAM0_TXVREFTUNE(x) __set(x, 25, 22)
+#define PHYPARAM0_TXISETUNE(x) __set(x, 21, 20)
+#define PHYPARAM0_TXRESTUNE(x) __set(x, 19, 18)
+#define PHYPARAM0_TXPREEMPPULSETUNE BIT(17)
+#define PHYPARAM0_TXPREEMPAMPTUNE(x) __set(x, 16, 15)
+#define PHYPARAM0_TXHSXVTUNE(x) __set(x, 14, 13)
+#define PHYPARAM0_TXFSLSTUNE(x) __set(x, 12, 9)
+#define PHYPARAM0_SQRXTUNE(x) __set(x, 8, 6)
+#define PHYPARAM0_OTGTUNE(x) __set(x, 5, 3)
+#define PHYPARAM0_COMPDISTUNE(x) __set(x, 2, 0)

#define EXYNOS5_DRD_PHYPARAM1 0x20

@@ -365,9 +376,30 @@ static void exynos5_usbdrd_utmi_init(struct exynos5_usbdrd_phy *phy_drd)
u32 reg;

reg = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYPARAM0);
- /* Set Loss-of-Signal Detector sensitivity */
- reg &= ~PHYPARAM0_REF_LOSLEVEL_MASK;
- reg |= PHYPARAM0_REF_LOSLEVEL;
+ /* Set Loss-of-Signal Detector sensitivity */
+ reg |= (PHYPARAM0_REF_USE_PAD |
+ /* Sets the sensitivity level for the Loss-of-Signal detector */
+ PHYPARAM0_REF_LOSLEVEL(0x9) |
+ /* Adjusts the high-speed DC level voltage */
+ PHYPARAM0_TXVREFTUNE(0x3) |
+ /* Adjust the rise/fal timie of the high-speed waveform */
+ PHYPARAM0_TXISETUNE(0x1) |
+ /* Adjusts the driver source impedance */
+ PHYPARAM0_TXRESTUNE(0x1) |
+ /* HS Transmitter Pre-Emphasis Duration Control */
+ PHYPARAM0_TXPREEMPPULSETUNE |
+ /* HS Transmitter Pre-Emphasis Current Control */
+ PHYPARAM0_TXPREEMPAMPTUNE(0x0) |
+ /* Transmitter High-Speed Crossover Adjustment */
+ PHYPARAM0_TXHSXVTUNE(0x3) |
+ /* FS/LS Source Impedance Adjustment */
+ PHYPARAM0_TXFSLSTUNE(0x3) |
+ /* Squelch Threshold Adjustment */
+ PHYPARAM0_SQRXTUNE(0x3) |
+ /* VBUS Valid Threshold Adjustment */
+ PHYPARAM0_OTGTUNE(0x6) |
+ /* Disconnect Threshold Adjustment */
+ PHYPARAM0_COMPDISTUNE(0x6));
writel(reg, phy_drd->reg_phy + EXYNOS5_DRD_PHYPARAM0);

reg = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYPARAM1);
--
2.22.0