diff options
Diffstat (limited to 'cpu')
| -rw-r--r-- | cpu/ppc4xx/cpu_init.c | 65 |
1 files changed, 60 insertions, 5 deletions
diff --git a/cpu/ppc4xx/cpu_init.c b/cpu/ppc4xx/cpu_init.c index ccd9993..8a6e545 100644 --- a/cpu/ppc4xx/cpu_init.c +++ b/cpu/ppc4xx/cpu_init.c @@ -111,17 +111,72 @@ void reconfigure_pll(u32 new_cpu_freq) mtcpr(CPR0_SPCID, reg); reset_needed = 1; } + } + + /* Get current value of FWDVA.*/ + mfcpr(CPR0_PLLD, reg); + temp = (reg & PLLD_FWDVA_MASK) >> 16; - /* Set reload inhibit so configuration will persist across - * processor resets */ + /* + * Check to see if FWDVA has been set to value of 1. if it has we must + * modify it. + */ + if (temp == 1) { + mfcpr(CPR0_PLLD, reg); + /* Get current value of fbdv. */ + temp = (reg & PLLD_FBDV_MASK) >> 24; + fbdv = temp ? temp : 32; + /* Get current value of lfbdv. */ + temp = (reg & PLLD_LFBDV_MASK); + lfbdv = temp ? temp : 64; + /* + * Load register that contains current boot strapping option. + */ + mfcpr(CPR0_ICFG, reg); + /* Shift strapping option into low 3 bits.*/ + reg = (reg >> 28); + + if ((reg == BOOT_STRAP_OPTION_A) || (reg == BOOT_STRAP_OPTION_B) || + (reg == BOOT_STRAP_OPTION_D) || (reg == BOOT_STRAP_OPTION_E)) { + /* + * Get current value of FWDVA. Assign current FWDVA to + * new FWDVB. + */ + mfcpr(CPR0_PLLD, reg); + target_fwdvb = (reg & PLLD_FWDVA_MASK) >> 16; + fwdvb = target_fwdvb ? target_fwdvb : 8; + /* + * Get current value of FWDVB. Assign current FWDVB to + * new FWDVA. + */ + target_fwdva = (reg & PLLD_FWDVB_MASK) >> 8; + fwdva = target_fwdva ? target_fwdva : 16; + /* + * Update CPR0_PLLD with switched FWDVA and FWDVB. + */ + reg &= ~(PLLD_FWDVA_MASK | PLLD_FWDVB_MASK | + PLLD_FBDV_MASK | PLLD_LFBDV_MASK); + reg |= ((fwdva == 16 ? 0 : fwdva) << 16) | + ((fwdvb == 8 ? 0 : fwdvb) << 8) | + ((fbdv == 32 ? 0 : fbdv) << 24) | + (lfbdv == 64 ? 0 : lfbdv); + mtcpr(CPR0_PLLD, reg); + /* Acknowledge that a reset is required. */ + reset_needed = 1; + } + } + + if (reset_needed) { + /* + * Set reload inhibit so configuration will persist across + * processor resets + */ mfcpr(CPR0_ICFG, reg); reg &= ~CPR0_ICFG_RLI_MASK; reg |= 1 << 31; mtcpr(CPR0_ICFG, reg); - } - /* Reset processor if configuration changed */ - if (reset_needed) { + /* Reset processor if configuration changed */ __asm__ __volatile__ ("sync; isync"); mtspr(SPRN_DBCR0, 0x20000000); } |