[U-Boot] [PATCH v4 2/8] armv8: Add workaround for USB erratum A-009798

[Ran Wang <ran.wang_1@nxp.com>]

The default setting for USB High Speed Squelch Threshold results
in a threshold close to or lower than 100mV. This leads to Receiver
Compliance test failure for a 100mV threshold.

Shift the threshold from ~100mV towards ~130mV by setting SQRXTUNE
to 0x0 to pass USB High Speed Receiver Sensitivity Compliance test.

Signed-off-by: Sriram Dash <sriram.dash@nxp.com>
Signed-off-by: Rajesh Bhagat <rajesh.bhagat@nxp.com>
Signed-off-by: Suresh Gupta <suresh.gupta@nxp.com>
Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
---
Change in v4:
	Update commit message about register setting.
	Clean up the math in set_usb_sqrxtune().
	Rename USB_TXVREFTUNE to SCFG_USB_TXVREFTUNE.

Change in v3:
	Use inline function to make code cleaner.

Change in v2:
	In function erratum_a009798():
	1.Put a blank line after variable declaration.
	2.Move common code together.

 arch/arm/cpu/armv8/fsl-layerscape/Kconfig          |  5 ++++
 arch/arm/cpu/armv8/fsl-layerscape/soc.c            | 27 ++++++++++++++++++++++
 .../include/asm/arch-fsl-layerscape/immap_lsch2.h  |  1 +
 .../include/asm/arch-fsl-layerscape/immap_lsch3.h  |  1 +
 4 files changed, 34 insertions(+)

diff --git a/arch/arm/cpu/armv8/fsl-layerscape/Kconfig b/arch/arm/cpu/armv8/fsl-layerscape/Kconfig
index d8936a4334..6677f2309a 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/Kconfig
+++ b/arch/arm/cpu/armv8/fsl-layerscape/Kconfig
@@ -23,6 +23,7 @@ config ARCH_LS1043A
 	select SYS_FSL_ERRATUM_A010315
 	select SYS_FSL_ERRATUM_A010539
 	select SYS_FSL_ERRATUM_A009008
+	select SYS_FSL_ERRATUM_A009798
 	select SYS_FSL_HAS_DDR3
 	select SYS_FSL_HAS_DDR4
 	select ARCH_EARLY_INIT_R
@@ -46,6 +47,7 @@ config ARCH_LS1046A
 	select SYS_FSL_ERRATUM_A010165
 	select SYS_FSL_ERRATUM_A010539
 	select SYS_FSL_ERRATUM_A009008
+	select SYS_FSL_ERRATUM_A009798
 	select SYS_FSL_HAS_DDR4
 	select SYS_FSL_SRDS_2
 	select ARCH_EARLY_INIT_R
@@ -83,6 +85,7 @@ config ARCH_LS2080A
 	select SYS_FSL_ERRATUM_A010165
 	select SYS_FSL_ERRATUM_A009203
 	select SYS_FSL_ERRATUM_A009008
+	select SYS_FSL_ERRATUM_A009798
 	select ARCH_EARLY_INIT_R
 	select BOARD_EARLY_INIT_F
 
@@ -229,6 +232,8 @@ config SYS_FSL_ERRATUM_A010539
 config SYS_FSL_ERRATUM_A009008
 	bool "Workaround for USB PHY erratum A009008"
 
+config SYS_FSL_ERRATUM_A009798
+	bool "Workaround for USB PHY erratum A009798"
 
 config MAX_CPUS
 	int "Maximum number of CPUs permitted for Layerscape"
diff --git a/arch/arm/cpu/armv8/fsl-layerscape/soc.c b/arch/arm/cpu/armv8/fsl-layerscape/soc.c
index 52a7abd13c..c00f732dc8 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/soc.c
+++ b/arch/arm/cpu/armv8/fsl-layerscape/soc.c
@@ -66,6 +66,7 @@ static void erratum_a009008(void)
 {
 #ifdef CONFIG_SYS_FSL_ERRATUM_A009008
 	u32 __iomem *scfg = (u32 __iomem *)SCFG_BASE;
+
 #if defined(CONFIG_ARCH_LS1043A) || defined(CONFIG_ARCH_LS1046A)
 	set_usb_txvreftune(scfg, SCFG_USB3PRM1CR_USB1);
 	set_usb_txvreftune(scfg, SCFG_USB3PRM1CR_USB2);
@@ -76,6 +77,30 @@ static void erratum_a009008(void)
 #endif /* CONFIG_SYS_FSL_ERRATUM_A009008 */
 }
 
+static inline void set_usb_sqrxtune(u32 __iomem *scfg, u32 offset)
+{
+	u32 val;
+
+	val = scfg_in32(scfg + offset / 4);
+	val &= ~(SCFG_USB_SQRXTUNE_MASK << 23);
+	scfg_out32(scfg + offset / 4, val);
+}
+
+static void erratum_a009798(void)
+{
+#ifdef CONFIG_SYS_FSL_ERRATUM_A009798
+	u32 __iomem *scfg = (u32 __iomem *)SCFG_BASE;
+
+#if defined(CONFIG_ARCH_LS1043A) || defined(CONFIG_ARCH_LS1046A)
+	set_usb_sqrxtune(scfg, SCFG_USB3PRM1CR_USB1);
+	set_usb_sqrxtune(scfg, SCFG_USB3PRM1CR_USB2);
+	set_usb_sqrxtune(scfg, SCFG_USB3PRM1CR_USB3);
+#elif defined(CONFIG_ARCH_LS2080A)
+	set_usb_sqrxtune(scfg, SCFG_USB3PRM1CR);
+#endif
+#endif /* CONFIG_SYS_FSL_ERRATUM_A009798 */
+}
+
 #if defined(CONFIG_FSL_LSCH3)
 /*
  * This erratum requires setting a value to eddrtqcr1 to
@@ -223,6 +248,7 @@ void fsl_lsch3_early_init_f(void)
 	erratum_a008514();
 	erratum_a008336();
 	erratum_a009008();
+	erratum_a009798();
 #ifdef CONFIG_CHAIN_OF_TRUST
 	/* In case of Secure Boot, the IBR configures the SMMU
 	* to allow only Secure transactions.
@@ -499,6 +525,7 @@ void fsl_lsch2_early_init_f(void)
 	erratum_a009660();
 	erratum_a010539();
 	erratum_a009008();
+	erratum_a009798();
 }
 #endif
 
diff --git a/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch2.h b/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch2.h
index c60d8ddfa2..323c098888 100644
--- a/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch2.h
+++ b/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch2.h
@@ -343,6 +343,7 @@ struct ccsr_gur {
 #define SCFG_USB3PRM1CR_USB2		0x07C
 #define SCFG_USB3PRM1CR_USB3		0x088
 #define SCFG_USB_TXVREFTUNE			0x9
+#define SCFG_USB_SQRXTUNE_MASK		0x7
 
 #define SCFG_SNPCNFGCR_SECRDSNP		0x80000000
 #define SCFG_SNPCNFGCR_SECWRSNP		0x40000000
diff --git a/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch3.h b/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch3.h
index 01b24d03f1..3b2e9eaa8b 100644
--- a/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch3.h
+++ b/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch3.h
@@ -134,6 +134,7 @@
 #define SCFG_USB3PRM1CR			0x000
 #define SCFG_USB3PRM1CR_INIT		0x27672b2a
 #define SCFG_USB_TXVREFTUNE		0x9
+#define SCFG_USB_SQRXTUNE_MASK	0x7
 #define SCFG_QSPICLKCTLR	0x10
 
 #define TP_ITYP_AV		0x00000001	/* Initiator available */
-- 
2.14.1