[U-Boot] [PATCH 3/5] Add 'Wait for JTAG user' if booted in JTAG mode

Graeme Russ gruss at tss-engineering.com
Wed Jan 21 12:55:16 CET 2015


When booting in JTAG mode, there is no way to use soft break-points, and
no way of knowing when SPL has finished executing (so the user can issue
a 'halt' command to load u-boot.bin for example)

Add a debug output and simple loop to stop execution at the completion of
the SPL initialisation as a pseudo break-point when booting in JTAG mode

Signed-off-by: Graeme Russ <gruss at tss-engineering.com>
---

 arch/arm/cpu/arm926ejs/mxs/spl_boot.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm/cpu/arm926ejs/mxs/spl_boot.c b/arch/arm/cpu/arm926ejs/mxs/spl_boot.c
index 2a5f817..7bfc623 100644
--- a/arch/arm/cpu/arm926ejs/mxs/spl_boot.c
+++ b/arch/arm/cpu/arm926ejs/mxs/spl_boot.c
@@ -157,6 +157,12 @@ void mxs_common_spl_init(const uint32_t arg, const uint32_t *resptr,
 	data->boot_mode_idx = bootmode;
 
 	mxs_power_wait_pswitch();
+
+
+	if (mxs_boot_modes[data->boot_mode_idx].boot_pads == 0x06) {
+		debug("SPL: Waiting for JTAG user\n");
+		asm volatile ("x: b x");
+	}
 }
 
 /* Support aparatus */
-- 
1.9.3



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