phy: uniphier-pcie: Fix updating phy parameters

[ Upstream commit 4a90bbb ]

The current driver uses a value from register TEST_O as the original
value for register TEST_I, though, the value is overwritten by "param",
so there is a bug that the original value isn't no longer used.

The value of TEST_O[7:0] should be masked with "mask", replaced with
"param", and placed in the bitfield TESTI_DAT_MASK as new TEST_I value.

Fixes: c6d9b13 ("phy: socionext: add PCIe PHY driver support")
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Link: https://lore.kernel.org/r/1623037842-19363-1-git-send-email-hayashi.kunihiko@socionext.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/phy/socionext/phy-uniphier-pcie.c

@@ -24,11 +24,13 @@
 #define PORT_SEL_1		FIELD_PREP(PORT_SEL_MASK, 1)
 
 #define PCL_PHY_TEST_I		0x2000
-#define PCL_PHY_TEST_O		0x2004
 #define TESTI_DAT_MASK		GENMASK(13, 6)
 #define TESTI_ADR_MASK		GENMASK(5, 1)
 #define TESTI_WR_EN		BIT(0)
 
+#define PCL_PHY_TEST_O		0x2004
+#define TESTO_DAT_MASK		GENMASK(7, 0)
+
 #define PCL_PHY_RESET		0x200c
 #define PCL_PHY_RESET_N_MNMODE	BIT(8)	/* =1:manual */
 #define PCL_PHY_RESET_N		BIT(0)	/* =1:deasssert */
@@ -77,11 +79,12 @@ static void uniphier_pciephy_set_param(struct uniphier_pciephy_priv *priv,
 	val  = FIELD_PREP(TESTI_DAT_MASK, 1);
 	val |= FIELD_PREP(TESTI_ADR_MASK, reg);
 	uniphier_pciephy_testio_write(priv, val);
-	val = readl(priv->base + PCL_PHY_TEST_O);
+	val = readl(priv->base + PCL_PHY_TEST_O) & TESTO_DAT_MASK;
 
 	/* update value */
-	val &= ~FIELD_PREP(TESTI_DAT_MASK, mask);
-	val  = FIELD_PREP(TESTI_DAT_MASK, mask & param);
+	val &= ~mask;
+	val |= mask & param;
+	val = FIELD_PREP(TESTI_DAT_MASK, val);
 	val |= FIELD_PREP(TESTI_ADR_MASK, reg);
 	uniphier_pciephy_testio_write(priv, val);
 	uniphier_pciephy_testio_write(priv, val | TESTI_WR_EN);