On Wed, Jun 20, 2012 at 07:56:44AM -0700, Brandt, Chris wrote:

quoted

I would be very happy if someone with access to
the documentation could shed some further light on this.

According to the SH7757 manual, setting the CLKDIV[3:0] in the CE_CLK_CTRL register 0xF selects Pck as the bus clock frequency. So, unlike other devices where Pck/2 (CLKDIV[3:0]=0) is the max bus speed, the SH7757 can run at Pck when CLKDIV=0xF.

Thanks Chris,

please correct me if I am wrong, but that seems to indicate the heuristic
is correct. At least for the sh7757 and sh7372.