[U-Boot] [PATCH resend] at91: Enable slow master clock on meesc board
Daniel Gorsulowski
Daniel.Gorsulowski at esd.eu
Mon Nov 23 10:04:50 CET 2009
In some cases, we need low speed master clock. So depending on the
"mdiv" variable, the processor clock is divided by 2 (default) or 4.
Signed-off-by: Daniel Gorsulowski <Daniel.Gorsulowski at esd.eu>
---
board/esd/meesc/meesc.c | 24 ++++++++++++++++++++++++
include/configs/meesc.h | 1 +
2 files changed, 25 insertions(+), 0 deletions(-)
diff --git a/board/esd/meesc/meesc.c b/board/esd/meesc/meesc.c
index efba60d..4f6c5b7 100644
--- a/board/esd/meesc/meesc.c
+++ b/board/esd/meesc/meesc.c
@@ -219,6 +219,30 @@ u32 get_board_rev(void)
}
#endif
+#ifdef CONFIG_MISC_INIT_R
+int misc_init_r(void)
+{
+ char *str;
+ char buf[32];
+
+ /*
+ * In some cases, we need low speed master clock. So depending on the
+ * "mdiv" variable, the processor clock is divided by 2 (default) or 4.
+ */
+ if ((str = getenv("mdiv")) && (!strcmp(str, "4"))) {
+ at91_sys_write(AT91_PMC_MCKR,
+ (at91_sys_read(AT91_PMC_MCKR) & ~AT91_PMC_MDIV) |
+ AT91SAM9_PMC_MDIV_4);
+ at91_clock_init(0);
+ serial_setbrg();
+ printf("Setting master clock to %s MHz\n",
+ strmhz(buf, get_mck_clk_rate()));
+ }
+
+ return 0;
+}
+#endif /* CONFIG_MISC_INIT_R */
+
int board_init(void)
{
/* Peripheral Clock Enable Register */
diff --git a/include/configs/meesc.h b/include/configs/meesc.h
index b996854..034e81c 100644
--- a/include/configs/meesc.h
+++ b/include/configs/meesc.h
@@ -48,6 +48,7 @@
#define CONFIG_SKIP_LOWLEVEL_INIT
#define CONFIG_SKIP_RELOCATE_UBOOT
+#define CONFIG_MISC_INIT_R /* Call misc_init_r */
#define CONFIG_ARCH_CPU_INIT
--
1.5.3
More information about the U-Boot
mailing list