[PATCH v2] asm/debug_ll_ns16550.h: add parament divisor
Du Huanpeng
u74147 at gmail.com
Sun Sep 27 05:32:57 EDT 2020
From: duhuanpeng <u74147 at gmail.com>
add a parameters for the assembly version for passing divisor,
and set the default value to DEBUG_LL_UART_ADDR when no parameter
is given.
now it is possiable to recalculate divisor in runtime to keep
the baudrate unchanged. when pll settings changed outside of barebox.
e.g. jtag.
Signed-off-by: duhuanpeng <u74147 at gmail.com>
---
arch/mips/include/asm/debug_ll_ns16550.h | 4 ++--
arch/riscv/include/asm/debug_ll_ns16550.h | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/mips/include/asm/debug_ll_ns16550.h b/arch/mips/include/asm/debug_ll_ns16550.h
index df58c4c..703bfae 100644
--- a/arch/mips/include/asm/debug_ll_ns16550.h
+++ b/arch/mips/include/asm/debug_ll_ns16550.h
@@ -58,14 +58,14 @@ static inline void PUTC_LL(char ch)
* Macros for use in assembly language code
*/
-.macro debug_ll_ns16550_init
+.macro debug_ll_ns16550_init divisor=DEBUG_LL_UART_DIVISOR
#ifdef CONFIG_DEBUG_LL
la t0, DEBUG_LL_UART_ADDR
li t1, UART_LCR_DLAB /* DLAB on */
sb t1, UART_LCR(t0) /* Write it out */
- li t1, DEBUG_LL_UART_DIVISOR
+ li t1, \divisor
sb t1, UART_DLL(t0) /* write low order byte */
srl t1, t1, 8
sb t1, UART_DLM(t0) /* write high order byte */
diff --git a/arch/riscv/include/asm/debug_ll_ns16550.h b/arch/riscv/include/asm/debug_ll_ns16550.h
index e891cbd..f1c2ccb 100644
--- a/arch/riscv/include/asm/debug_ll_ns16550.h
+++ b/arch/riscv/include/asm/debug_ll_ns16550.h
@@ -88,14 +88,14 @@ static inline void debug_ll_ns16550_init(void)
* Macros for use in assembly language code
*/
-.macro debug_ll_ns16550_init
+.macro debug_ll_ns16550_init divisor=DEBUG_LL_UART_DIVISOR
#ifdef CONFIG_DEBUG_LL
li t0, DEBUG_LL_UART_ADDR
li t1, UART_LCR_DLAB /* DLAB on */
UART_REG_S t1, UART_LCR(t0) /* Write it out */
- li t1, DEBUG_LL_UART_DIVISOR
+ li t1, \divisor
UART_REG_S t1, UART_DLL(t0) /* write low order byte */
srl t1, t1, 8
UART_REG_S t1, UART_DLM(t0) /* write high order byte */
--
2.7.4
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