feat(st-uart): manage STM32MP_RECONFIGURE_CONSOLE

If the flag STM32MP_RECONFIGURE_CONSOLE is set in BL32, the UART init
should be skipped if the UART clock is set to zero. This will be used
when configuring the default console, after an early console has been
configured.

Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Change-Id: Icbc640c7bdd6342f9c3ec1586a0d0c64127b18b8

drivers/st/uart/aarch32/stm32_console.S

@@ -46,10 +46,16 @@ func console_stm32_core_init
 	cmp	r0, #0
 	beq	core_init_fail
 #if !defined(IMAGE_BL2)
+#if STM32MP_RECONFIGURE_CONSOLE
+	/* UART clock rate is set to 0 in BL32, skip init in that case */
+	cmp	r1, #0
+	beq	1f
+#else /* STM32MP_RECONFIGURE_CONSOLE */
 	/* Skip UART initialization if it is already enabled */
 	ldr	r3, [r0, #USART_CR1]
 	ands	r3, r3, #USART_CR1_UE
 	bne	1f
+#endif /* STM32MP_RECONFIGURE_CONSOLE */
 #endif /* IMAGE_BL2 */
 	/* Check baud rate and uart clock for sanity */
 	cmp	r1, #0