[U-Boot] [PATCH v6 28/28] armv8/fsl-lsch3: Implement workaround for I2C erratum A009203

[York Sun]

This erratum requires setting GLITCH_EN bit in debug register to
enable digital filter to improve clock stability.

Signed-off-by: York Sun <yorksun at freescale.com>
CC: Heiko Schocher <hs at denx.de>

---

Changes in v6:
  Add erratum number

Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2:
  Add comment to I2C workaround

 arch/arm/cpu/armv8/fsl-lsch3/soc.c |   34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/arch/arm/cpu/armv8/fsl-lsch3/soc.c b/arch/arm/cpu/armv8/fsl-lsch3/soc.c
index ca00108..2538001 100644
--- a/arch/arm/cpu/armv8/fsl-lsch3/soc.c
+++ b/arch/arm/cpu/armv8/fsl-lsch3/soc.c
@@ -37,11 +37,45 @@ static void erratum_rcw_src(void)
 #endif
 }
 
+#define I2C_DEBUG_REG 0x6
+#define I2C_GLITCH_EN 0x8
+/*
+ * This erratum requires setting glitch_en bit to enable
+ * digital glitch filter to improve clock stability.
+ */
+static void erratum_a009203(void)
+{
+	u8 __iomem *ptr;
+#ifdef CONFIG_SYS_I2C
+#ifdef I2C1_BASE_ADDR
+	ptr = (u8 __iomem *)(I2C1_BASE_ADDR + I2C_DEBUG_REG);
+
+	writeb(I2C_GLITCH_EN, ptr);
+#endif
+#ifdef I2C2_BASE_ADDR
+	ptr = (u8 __iomem *)(I2C2_BASE_ADDR + I2C_DEBUG_REG);
+
+	writeb(I2C_GLITCH_EN, ptr);
+#endif
+#ifdef I2C3_BASE_ADDR
+	ptr = (u8 __iomem *)(I2C3_BASE_ADDR + I2C_DEBUG_REG);
+
+	writeb(I2C_GLITCH_EN, ptr);
+#endif
+#ifdef I2C4_BASE_ADDR
+	ptr = (u8 __iomem *)(I2C4_BASE_ADDR + I2C_DEBUG_REG);
+
+	writeb(I2C_GLITCH_EN, ptr);
+#endif
+#endif
+}
+
 void fsl_lsch3_early_init_f(void)
 {
 	erratum_a008751();
 	erratum_rcw_src();
 	init_early_memctl_regs();	/* tighten IFC timing */
+	erratum_a009203();
 }
 
 #ifdef CONFIG_SPL_BUILD
-- 
1.7.9.5