[U-Boot] [PATCH 3/3] imx: mx6: hdmi: handle overflow condition

[Peng Fan]

If HDMI_IH_FC_STAT2_OVERFLOW_MASK is set, we need to
do TMDS software reset and write to clear fc_invidconf register.
We need minimum 3 times to write to clear the fc_invidconf
register, so choose 5 loops here.

Signed-off-by: Peng Fan <van.freenix at gmail.com>
Signed-off-by: Sandor Yu <sandor.yu at nxp.com>
Cc: Stefano Babic <sbabic at denx.de>
Cc: Fabio Estevam <fabio.estevam at nxp.com>
---
 arch/arm/cpu/armv7/mx6/soc.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/arch/arm/cpu/armv7/mx6/soc.c b/arch/arm/cpu/armv7/mx6/soc.c
index a34675c..91a3deb 100644
--- a/arch/arm/cpu/armv7/mx6/soc.c
+++ b/arch/arm/cpu/armv7/mx6/soc.c
@@ -548,7 +548,8 @@ void imx_setup_hdmi(void)
 {
 	struct mxc_ccm_reg *mxc_ccm = (struct mxc_ccm_reg *)CCM_BASE_ADDR;
 	struct hdmi_regs *hdmi  = (struct hdmi_regs *)HDMI_ARB_BASE_ADDR;
-	int reg;
+	int reg, count;
+	u8 val;
 
 	/* Turn on HDMI PHY clock */
 	reg = readl(&mxc_ccm->CCGR2);
@@ -565,6 +566,16 @@ void imx_setup_hdmi(void)
 		 |(CHSCCDR_IPU_PRE_CLK_540M_PFD
 		 << MXC_CCM_CHSCCDR_IPU1_DI0_PRE_CLK_SEL_OFFSET);
 	writel(reg, &mxc_ccm->chsccdr);
+
+	/* Clear the overflow condition */
+	if (readb(&hdmi->ih_fc_stat2) & HDMI_IH_FC_STAT2_OVERFLOW_MASK) {
+		/* TMDS software reset */
+		writeb((u8)~HDMI_MC_SWRSTZ_TMDSSWRST_REQ, &hdmi->mc_swrstz);
+		val = readb(&hdmi->fc_invidconf);
+		/* Need minimum 3 times to write to clear the register */
+		for (count = 0 ; count < 5 ; count++)
+			writeb(val, &hdmi->fc_invidconf);
+	}
 }
 #endif
 
-- 
2.6.2