[U-Boot] [PATCH v3 2/4] rk3288: Disable JTAG function from sdmmc0 IO

[Carlo Caione]

From: Carlo Caione <carlo at endlessm.com>

The GRF_SOC_CON0.grf_force_jtag bit is automatically set at boot and it
is preventing the SDMMC to work correctly. Disable the JTAG function on
the assumption that a working SD has higher priority over JTAG.

Signed-off-by: Carlo Caione <carlo at endlessm.com>
Reviewed-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
Acked-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
---
 arch/arm/mach-rockchip/rk3288-board.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm/mach-rockchip/rk3288-board.c b/arch/arm/mach-rockchip/rk3288-board.c
index 0365793009..bf24d8e074 100644
--- a/arch/arm/mach-rockchip/rk3288-board.c
+++ b/arch/arm/mach-rockchip/rk3288-board.c
@@ -307,6 +307,7 @@ U_BOOT_CMD(
 	""
 );
 
+#define GRF_SOC_CON0 0xff770244
 #define GRF_SOC_CON2 0xff77024c
 
 int board_early_init_f(void)
@@ -339,5 +340,11 @@ int board_early_init_f(void)
 	}
 	rk_setreg(GRF_SOC_CON2, 1 << 0);
 
+	/*
+	 * Disable JTAG on sdmmc0 IO. The SDMMC won't work until this bit is
+	 * cleared
+	 */
+	rk_clrreg(GRF_SOC_CON0, 1 << 12);
+
 	return 0;
 }
-- 
2.17.1