[U-Boot] [PATCH][RESEND] at91: Enable slow master clock on meesc board

Daniel Gorsulowski Daniel.Gorsulowski at esd.eu
Wed Jan 20 08:00:11 CET 2010


Normally the processor clock has a divisor of 2.
In some cases this this needs to be set to 4.
Check the user has set environment mdiv to 4 to change the divisor.

Signed-off-by: Daniel Gorsulowski <Daniel.Gorsulowski at esd.eu>
---
v2: - changed and add additional comments
    - strengthened string comparision

 board/esd/meesc/meesc.c | 26 ++++++++++++++++++++++++++
 include/configs/meesc.h |    1 +
 2 files changed, 27 insertions(+), 0 deletions(-)

diff --git a/board/esd/meesc/meesc.c b/board/esd/meesc/meesc.c
index efba60d..a1b66cb 100644
--- a/board/esd/meesc/meesc.c
+++ b/board/esd/meesc/meesc.c
@@ -219,6 +219,32 @@ u32 get_board_rev(void)
 }
 #endif
 
+#ifdef CONFIG_MISC_INIT_R
+int misc_init_r(void)
+{
+	char *str;
+	char buf[32];
+
+	/*
+	 * Normally the processor clock has a divisor of 2.
+	 * In some cases this this needs to be set to 4.
+	 * Check the user has set environment mdiv to 4 to change the divisor.
+	 */
+	if ((str = getenv("mdiv")) && (strcmp(str, "4") == 0)) {
+		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();
+		/* Notify the user that the clock is not default */
+		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
 
-- 
1.6.1



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