mpc83xx: Replace CONFIG_83XX_CLKIN in calculations

CONFIG_SYS_CLK_FREQ is the standard way to set the system clock
frequency. On MPC83xx, CONFIG_83XX_CLKIN is used for this purpose.
Hence, the obvious way is to replace CONFIG_83XX_CLKIN with
CONFIG_SYS_CLK_FREQ.

A few MPC83xx boards use the CONFIG_83XX_CLKIN variable for computing
CONFIG_SYS_NS16550_CLK. This makes it harder to replace
CONFIG_83XX_CLKIN.

But the value of the multiplicator can be read from the SPMR register.

Hence, replace the static calculations with a call to a new get_bus_freq
function, as other architectures do.

Signed-off-by: Mario Six <mario.six@gdsys.cc>

1 files changed, 8 insertions, 0 deletions

diff --git a/arch/powerpc/cpu/mpc83xx/spl_minimal.c b/arch/powerpc/cpu/mpc83xx/spl_minimal.c
index 746f1febba..3315ee05e1 100644
--- a/arch/powerpc/cpu/mpc83xx/spl_minimal.c
+++ b/arch/powerpc/cpu/mpc83xx/spl_minimal.c
@@ -89,3 +89,11 @@ void puts(const char *str)
 	while (*str)
 		putc(*str++);
 }
+
+ulong get_bus_freq(ulong dummy)
+{
+	volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
+	u8 spmf = (im->clk.spmr & SPMR_SPMF) >> SPMR_SPMF_SHIFT;
+
+	return CONFIG_83XX_CLKIN * spmf;
+}