[U-Boot] [U-boot][PATCH] serial: sh: fix internal clock source on SCIF
Vladimir Barinov
vladimir.barinov at cogentembedded.com
Fri Feb 13 23:05:18 CET 2015
The formula to calculate SCIF BRR for R-Car H2/M2/E2 SoCs is as follows:
BRR = pclk / (64 * 2^(2n-1) * baudrate) - 1,
the prescaler is 0 due to SCSMR settings, hence n=0
Also SCSCR must be set to use internal or external clock source.
Signed-off-by: Vladimir Barinov <vladimir.barinov at cogentembedded.com>
---
drivers/serial/serial_sh.h | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/serial/serial_sh.h b/drivers/serial/serial_sh.h
index 528aa73..941e6ed 100644
--- a/drivers/serial/serial_sh.h
+++ b/drivers/serial/serial_sh.h
@@ -227,7 +227,8 @@ struct uart_port {
#elif defined(CONFIG_R8A7790) || defined(CONFIG_R8A7791) || \
defined(CONFIG_R8A7793) || defined(CONFIG_R8A7794)
# define SCIF_ORER 0x0001
-# define SCSCR_INIT(port) 0x32 /* TIE=0,RIE=0,TE=1,RE=1,REIE=0, */
+# define SCSCR_INIT(port) (port->clk_mode == EXT_CLK ? 0x32 : 0x30)
+ /* TIE=0,RIE=0,TE=1,RE=1,REIE=0, */
#else
# error CPU subtype not defined
#endif
@@ -742,7 +743,7 @@ static inline int scbrr_calc(struct uart_port *port, int bps, int clk)
#elif defined(CONFIG_R8A7790) || defined(CONFIG_R8A7791) || \
defined(CONFIG_R8A7793) || defined(CONFIG_R8A7794)
#define DL_VALUE(bps, clk) (clk / bps / 16) /* External Clock */
-#define SCBRR_VALUE(bps, clk) ((clk+16*bps)/(32*bps)-1) /* Internal Clock */
+#define SCBRR_VALUE(bps, clk) (clk / bps / 32 - 1) /* Internal Clock */
#else /* Generic SH */
#define SCBRR_VALUE(bps, clk) ((clk+16*bps)/(32*bps)-1)
#endif
--
1.9.1
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