Based on the Tegra TRM, the system clock (which is the AVP clock) can
run up to 275MHz. On power on, the default sytem clock source is set to
PLLP_OUT0. In function clock_early_init(), PLLP_OUT0 will be set to
408MHz which is beyond system clock's upper limit.
The fix is to set the system clock to CLK_M before initializing PLLP,
and then switch back to PLLP_OUT4, which has an appropriate divider
configured, after PLLP has been configured
Implement this logic in new function tegra30_set_up_pllp(),
which sets up PLLP and all PLLP_OUT* dividers, and handles the AVP
clock switching. Remove the duplicate PLLP setup from pllx_set_rate()
and adjust_pllp_out_freqs().
Signed-off-by: Jimmy Zhang <jimmzhang@nvidia.com>
[swarren, significantly refactored the change]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>