From ab10d73d2fc13bd5baf5024e54ad92641d238bdb Mon Sep 17 00:00:00 2001 From: York Sun Date: Mon, 23 Mar 2015 10:41:35 -0700 Subject: armv8/fsl-lsch3: Implement workaround for I2C erratum A009203 This erratum requires setting GLITCH_EN bit in debug register to enable digital filter to improve clock stability. Signed-off-by: York Sun CC: Heiko Schocher --- arch/arm/cpu/armv8/fsl-lsch3/soc.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) (limited to 'arch/arm/cpu/armv8/fsl-lsch3/soc.c') diff --git a/arch/arm/cpu/armv8/fsl-lsch3/soc.c b/arch/arm/cpu/armv8/fsl-lsch3/soc.c index ca00108e40..2538001bca 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 -- cgit v1.2.1