serial: sh: Add support External Clock mode

R8A7780 and R7A7791 of rmobile supports External Clock mode, and these uses
different from Internal Clock mode registers and calculations to the baud rate
setting. This adds function for External Clock mode.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>

diff --git a/drivers/serial/serial_sh.c b/drivers/serial/serial_sh.c
index 0826d59ab2adbba604665b520278898130e9fa59..144a925394513d38b1677030cb97fcc5f96d84cb 100644 (file)
--- a/drivers/serial/serial_sh.c
+++ b/drivers/serial/serial_sh.c
@@ -49,9 +49,15 @@ static struct uart_port sh_sci = {
 static void sh_serial_setbrg(void)
 {
        DECLARE_GLOBAL_DATA_PTR;
-
+#ifdef CONFIG_SCIF_USE_EXT_CLK
+       unsigned short dl = DL_VALUE(gd->baudrate, CONFIG_SH_SCIF_CLK_FREQ);
+       sci_out(&sh_sci, DL, dl);
+       /* Need wait: Clock * 1/dl \e$B!_\e(B 1/16 */
+       udelay((1000000 * dl * 16 / CONFIG_SYS_CLK_FREQ) * 1000 + 1);
+#else
        sci_out(&sh_sci, SCBRR,
                SCBRR_VALUE(gd->baudrate, CONFIG_SH_SCIF_CLK_FREQ));
+#endif
 }
 
 static int sh_serial_init(void)

diff --git a/drivers/serial/serial_sh.h b/drivers/serial/serial_sh.h
index 4f3e22530f95a0f3e9af957a2dcac6239a7fe1f4..fe8cde4dedb5ffe3ea9c33779841038cbc9e90d6 100644 (file)
--- a/drivers/serial/serial_sh.h
+++ b/drivers/serial/serial_sh.h
@@ -735,8 +735,8 @@ static inline int scbrr_calc(struct uart_port port, int bps, int clk)
 #elif defined(__H8300H__) || defined(__H8300S__)
 #define SCBRR_VALUE(bps, clk) (((clk*1000/32)/bps)-1)
 #elif defined(CONFIG_R8A7790) || defined(CONFIG_R8A7791)
-#define SCBRR DL
-#define SCBRR_VALUE(bps, clk) (clk / bps / 16)
+#define DL_VALUE(bps, clk) (clk / bps / 16) /* External Clock */
+#define SCBRR_VALUE(bps, clk) ((clk+16*bps)/(32*bps)-1) /* Internal Clock */
 #else /* Generic SH */
 #define SCBRR_VALUE(bps, clk) ((clk+16*bps)/(32*bps)-1)
 #endif